Beach Management Plan with Beach Management Districts

[From the U.S. Government Printing Office, www.gpo.gov]

BEACH MANAGEMENT PLAN
WITH
BEACH MANAGEMENT DISTRICTS

HAWAII COASTAL ZONE MANAGEMENT PROGRAM
OFFICE OF STATE PLANNING
OFFICE OF THE GOVERNOR

BEACH MANAGEMENT PLAN
WITH
BEACH MANAGEMENT DISTRICTS

Prepared by:

Dennis J. Hwang
1
801 Alakea St., Suite 212
Honolulu, Hawaii 96813

Dr. Charles H. Fletcher III
University of Hawaii
Dept. of Geology and Geophysics
Honolulu, Hawaii 96822

Prepared for:

Hawaii Coastal Zone Management Program
Office of State Planning
Office of the Governor

June 1992

The preparation of this report was financed in part by the Coastal Zone Management Act of 1972,
as amended, administered by the Office of Ocean and Coastal Resource Management, National
Oceanic and Atmospheric Administration, United States Department of Commerce, through the
Office of State Planning, State of Hawaii.
A*

EXECUTIVE SUMMARY

A qualitative analysis of 1990 aerial photographs for the island of -Oahu was
:J
conducted to ascertain the extent of beach degradation. By comparing the 1990
aerial photos with previous aerial photographs and coastal studies, it is estimated
that since 1928, gpproximately 8 to 9 miles, or close to 15% of the sand shorelines
studied on Oahu have either disWeared or have been negatively impacted by
shoreline stabilization.

Beach loss on Oahu gppears to have accelerated. Of the 8 to 9 miles of beach
that have been impacted, approximately half, or 4 to 5 miles, have been degraded
to the point that the beach is barely existent. Of these severely impacted
shorelines, approximately half, or 2 to 2.5 miles of beaches were lost in the last 10
to 15 years. The loss of sandy shoreline over this time was greater than any other
period studied.

Beach loss in the State due to hardening of the shoreline is not limited to the
island of Oahu. At a visit to selected sites, beach loss or recreational impacts
were found equalling I to 1.5 miles on Hawaii, 1 to 2 miles on Kauai, and 2.8 to
as much as 6 miles of actual or imminent impacts on Maui. A thorough analysis
of all the sandy shoreline on these islands would yield higher numbers.

Beach loss in the State has been concurrent with sea-level rise. An examination
of tide gauge records around the islands indicate relative sea-level on Oahu and
Kauai has risen .6-.7 in/decade. Because Hawaii and Maui are sinking due to
volcanic growth, relative sea-level rise for these islands has been almost double, or
approximately 1-1.5 in/decade.- The current trend of sea-level rise is projected to
accelerate. By the year 2050, the seas around Oahu and Kauai 'May be rising 2.4-
2.5 in/decade. Around Maui and Hawaii sea-level may rise at a rate of 2.8-3.4
in/decade. Planners should use the current rate of sea-level rise to estimate
minimum beach recession rates. The 2050 projection should be used to determine
maximum recession rates. Most likely, future sea-level rise will be between these
rates.

The link between sea-level rise and beach loss has serious implications. Due to
the gentle profile of many beaches, a small sea-level rise can lead to a large
J
landward movement of the waterline. At current rates of sea-level rise, a typical
beach on Oahu and Kauai may recede 5 ft/decade, on Maui, 7 ft/decade and on

Hawaii, 12 ft/decade. Accelerated sea-level risel as projected, could lead to
recession on Oahu and Kauai of 18 ft/decade, on Maui of 21 ft/decade and on
Hawaii of 35 ft/decadd.

Without changes in shoreline management, loss of beaches along the coast is
expected to accelerate for two reasons. First, each year, a greater percentage of the
State's sandy shoreline is stabilized with seawalls and revetments. Second, as sea-
level rises, these hardened barriers will have an increasing influence on beach
erosion because of increased interaction with the nearshore current and wave
regime. At the current rate of sea-level rise, evga narrow, gently sloping beach
in the State with an armored shoreline could be lost within the next 50 years. At
accelerated rates of sea-level rise, this problem will become critical.

Beaches provide a buffer zone from wave activity. As seas move inland and
beaches disappear, the susceptibility of coastal property and structures to wave
damage is expected to increase.

* This report discuss es options for the State that are commensurate with the
problems associated with beach loss and sea-level rise. Effort has been made to
consider solutions that are technically, legally and flnancially feasible. Solutions
are designed to balance the benefits and burdens of each impacted p4m, and to
respect private and public propeIV rights. The solutions should be viewed as
options that the State m4y or mgy not pursue. Implementation of some of the
solutions will require determination, commitrnent andleadership by the State.

Through Beach Management Districts -(BMDs), erosion mitigation measures other
than seawalls and revetments can be Dromoted. Where technical, financial and
legal obstacles prevent the formation of a BMD, buried structures such as gently
sloping revetinents or gravel berms should be the preferred erosion mitigation
option.

* There are many reasons why a coastal landowner may want to participate in the
formation of a beach management district. The major benefits include increased
long-term property protection from sea-level rise, and increased property values
from the presence of a healthy beach adjacent to the land.

BMI)s have been formed in numerous coastal states to deal with erosion. The
three most common variations include an improvement district, an overlay district

and a taxing district. Improvement and overlgy districts can be valuable tools to
help recover or preserve beaches. Because of the extent of shoreline degradation
around the islands, taxing districts do not appear suitable for Hawaii.

Other coastal states have used various fimding schemes to pay for the costs of
a BMD. This report recommends a shared cost scheme with contributions from the
State, cggnV and shoreline pEo= owners. Exact percentages can be worked out
between the State and counties at a later date. Given the proper coordination
between the State and the counties, suggested cost allocation ranges are State 60% -
45%; counties - 10%; shoreline property owner 45% - 30%. Contributions from
all three parties could be reduced if Federal assistance were obtained.

* A dedicated State Beach Fund could be established for the puEposes o
administeriniz and contributing to the capital improvements in a BMD. Resources
from the State Beach Fund may also be used for the acquisition of selected coastal
property. Money for the Beach Fund could be derived from legislative
appropriations, Federal programs where applicable, a shoreline property transfer
fee, landowner contributions or other sources.

A properly structured package of tax incentives, credits and fees could be used
to wport beach preservation. The package could include State income tax
deductions for landowner contributions over a threshold amount that go towards
financing a BMD. In addition, a small one time transfer -tax on the sale of
beachfront property would ensure a steady stream of income into the State Beach
Fund. Revenues from the transfer tax would rise as shorefront proper-ties increase
in value. The tax would be paid not by current homeowners, but by future buyers
of property. To make the transfer tax politically palatable, it could be linked with
a small reduction in property assessments, for homeowners that.are in compliance
with shoreline regulation, in order to reduce the property tax at the county level.
Thus, long-term shoreline property owners would benefit from the shoreline tax
package.

Beach Manaizement Districts Ma
y not be suitable for eveTY section of the coast.
For this reason, other management strategies were developed, including regulatory
proposals.

For nonurban land, or land that has not been subdivided, a setback is proposed
which is the greater of 60 feet, or 30 years times the averalZe annual erosion rate.,.

or the historical range in the position of the vegetation line as measured over a 30
year period. Thus, the setback would be based on local conditions for undeveloped
coastal areas. To avoid the takings issue, variances --should be allowed to preserve
buildable area. If a shoreline setback is greater than 60 feet, the State and counties
can reduce or eliminate the economic burden on the landowner by develgRing a
Rackage Of cOmRensating variances. Included in the land use package may be
provisions for reduced front and side setbacks, increased density of buildings,
increased height and transferable development rights. In addition, the shoreline
setback may be reduced for preapproved and prefinanced sand replenishment
projects. The recent U. S. Supreme Court decision in Lucas v. South Carolina
Coastal Council should not affect the zoning strategies developed in this report.

A counly Beach Enforcement Fund could be established to support shoreline
monitoring and enforcement activities. Money for the Beach Enforcement Fund
would be derived from legislative appropriations and fines for illegal activities.
Money from the Fund could be used for enforcement activities and to provide
subsidies to landowners to convert vertical seawalls to buried erosion control
structures.

* A State agency is needed to implement and administer mAny of the pLoposed
beach management programs. The agency could be established as a division, a
branch, or an office. Alternatively, the agency could be formed as a unit within
the Coastal Zone Management Program or the Department of Land and Natural
Resources. Assuming that a division is formed, the Division of State Beaches
would pursue Federal funding for erosion control projects; coordinate Federal,
State, county and landowner activities concerning coastal erosion; promote,
establish and administer Beach Management Districts; develop a voluntary
relocation program in conjunction with the Federal Emergency Management
Agency; administer the State Beach Fund; provide technical assistance to coastal
landowners, the State, and the county governments; and oversee scientific research
related to long-term beach monitoring, sand resources, natural process, storm
activity and sea-level rise.

TABLE OF CONTENTS

1. INTRODUCTION ...................................... I

11.. PROTECTING HAWAII'S SHORELINE .................... 5
A. Beach Degradation on Oahu .......................... 5
1. Iroquois Point ................................. 6
2. Kahala ..................................... 6
3. Northwest Lanikai ............................. 10
4. Southeast Lanikai ............................. 10
5. Punaluu .................................... 13
6. Mahie Point to Makaua Beach Park ................. 13
B. Beach Degradation On The Outer Islands ................. 16
1. Hawaii ..................................... 18
2. Maui ...................................... 21
3. Kauai ..................................... 26
C. Global and Local Sea-Level Rise ....................... 29
1. Global Sea Level .............................. 29
2. Hawaiian Sea-Levels ........................... 34
D. Prediction - Accelerated Beach Loss .................... 39
E. Mitigating the Problem - Modification of Coastal Land Use ..... 41
F. Cooperation, Coordination and Sacrifice .................. 44

III. PRIVATE & PUBLIC PROPERTY RIGHTS IN THE SHORELINE 45
A. Public Property Interest ............................. 45
B. Private Property Interest .............................. 48

IV. MANAGEMENT OBJECTIVES & STRATEGY ............... 52
A. Objectives ................ ... 52
B. Strategies ....................................... 53
1. Develop the Beach Management District .............. 53
2. Implement Economic Mechanisms in Beach Management . . 53
3. Achieve Regulatory Efficiency ..................... 54
4. Enforce Existing Regulations ...................... 56
5. Offset Burdens with Benefits ...................... 56
aj
V. BEACH MANAGEMENT DISTRICTS ...................... 57
A. The District Structure ............................... 57

1. The Overlay District . ..........
................. 57
2. The Improvement District ........................ 59
3. Taxing -Districts . .......... .............
..... 60
B. District Formation ................................... 61
C. Landowner Cooperation ............................. 62
D. Liability ........................................ 65
E. Procedures 65
F. Temporary Protection ............................... 66
G. Applicability ...................................... 66

VI. NONSTRUCTURAL AND STRUCTURAL OPTIONS ........... 68
A. Artificial Beach Nourishment ......................... 68
1. Concept .................................... 68
2. Planning .................................... 72
3. Sand ...................................... 73
4. Monitoring .................................. 80
5. Maintenance ................................. 80
6. Effect of Sea Level Rise ......................... 83
B. Structures Commonly Associated With Nourishment .......... 88
1. Detached Breakwater ........................... 88
2. Filled Terminal Groin ........................... 89
3. Perched Beach ............................... 89
4. Buried, Low-Angle Revetments .................... 89
C. Vertical Structures . ................................ go
D. Restrictions on Shoreline Structures . ..................... 97

VII. FUNDING .... 99
A. Sources of Funding .........................
........ 99
1. Federal . .................................... 99
2. State ....................................... 101
3. County . .................................... jol
4. Assessments ...... 102
5. Tax Incentives, Credits and Fees ................... 103
a. Tax Deductions ........................... 104
b. The Shoreline Property Transfer Tax ............ 104
6. Impact Fees, Easements, and Other Funding Sources ...... III
B. Funding a BMD - Cost Allocation ...................... III
1. Federal

vii

2. County ..................................... 112
3. Coastal Landowner ............................ 113
4. State ....................................... 114
C. State Beach Fund .................................. 114

VIII. REGULATORY OPTIONS ............................. 117
A. National Flood Insurance - Upton-Jones Amendment ......... 117
B. Zoning ......................................... 119
C. Enforcement ..................................... 125

IX. DIVISION OF STATE BEACHES ......................... 128

X. CASE STUDIES ...................................... 133
A. Ewa Beach ..................................... 133
1. Location .................................... 133
2. Zoning ..................................... 133
3. Socioeconomic Setting .......................... 133
4. Physical Setting ............................... 140
5. Historical Shoreline Changes ...................... 141
6. Beach Management Problems ..................... 141
7. Alternatives ................................. 143
a. Sand Replenishment ....................... 143
b. Buried Structures ......................... 144
c. Relocation or Removal ...................... 147
B. Kahala Beach .................................... 148
1. Location ..................................... 148
2. Zoning ...................................... 148
3. Social Setting ................................ 148
4. Beach Recovery .............................. 154
5. District Formation ............................. 161
6. Landowner Cooperation ......................... 165
7. Cost Allocation ............................... 166
a. Federal ................................ 166
b. Landowner .............................. 166
c. County ................................ 167
d. State .................................. 167

XI. RECOMMENDATIONS ............................... 169

viii

A. Beach Management Districts .......................... 169
B. Beach Management ................................ 171
C. Ewa Beach ....................................... 172
D. Kahala Beach .................................... 173

XII. IMPLEMENTATION GUIDELINES ....... 174
A. Public Education - Changing Public Perception .............. 174
B. State Agency Responsible for Beach Management ........... 175
C. State Agency Implements a Beachfront Management Program ... 177
D. Interim Measures ................................ 179
1. State ...................................... 179
2. County ..................................... 179
a. Overlay Districts .......................... 179
b. Improvement Districts ...................... 179
c. Overlay versus Improvement Districts ........... 180

XIII. CONCLUSIONS .................................... 181

XIV. REFERENCES ...................................... 187

LIST OF FIGURES

Figure 1. Map of Oahui Showing Figure Locations ................... 7
Figure 2. Iroquois Point, Oahu .............................. 8
Figure 3. Kahala Beach, Oahu ............................... 9
Figure 4. Northwest Lanikai, Oahu ........................... 11
Figure 5. Southeast Lanikai, Oahu ............................ 12
Figure 6. Punaluu Beach, Oahu .............................. 14
Figure 7. Mahie Point to Makaua Beach Park, Oahu ................ 15
Figure 8. Beach Degradation on Oahu ............ : * '* *" ' * ** ** ... 17
Figure 9. The Stone Revetment at Hilo Harbor, Hawaii .............. 19
Figure 10. Kona Coast of Hawaii ............................. 19
Figure 11. West Maalaea Bay, Maui ........................... 22
Figure 12. Vegetated Revetment near Kihei, Maui .................. 22
Figure 13. Kalama Beach Park, Maui .......................... 24
Figure 14. Waimahaihai Beach, Maui .............. ; ............ 24
Figure 15. Honokowai Beach Park, north of Lahaina, Maui ........... 25
Figure 16. Punahoa Beach south of Lahaina, Maui ................. 25
Figure 17. Kikiaola Harbor, Kauai ............................ 27
Figure 18. The Residential Beach at Waipoli, Kauai ................ 27
Figure 19. Intergovernmental Panel on Climate Change, 1990 .......... 30
Figure 20. Projected Sea-Level Rise ............................ 31
Figure 21. Local Sea-Level Trends ............................ 35
Figure 22. Lanikai and Kailua Beach, Oahu ...................... 43
Figure 23. Erosion of a Nourished Beach ........................ 70
Figure 24. Beachrock ..................................... 76
Figure 25. Offshore Sand Deposits ............................ 79
Figure 26. Hurricane Tracks ................................. 82
Figure 27. Coastal Inundation ................................ 82
Figure 28. The Bruun Rule ................................. 85
Figure 29. Plan-view of a Detached Breakwater ................... 85
Figure 30. Buried Revetment ................................ 91
Figure 3 1. Seawalls ...................................... 91
Figure 32. Seawall Impacts ................................. 93
Figure 33. Beach Profile Impacts ............................. 93
Figure 34. Seawalls ...................................... 95
Figure 35. Ewa Beach Location .............................. 134
Figure 36. Ewa Beach - Boundaries of Area of Interest .............. 135

Figure 37. Hawaii Land Use District Map for Ewa ................. 136
Figure 38. Oahu Development Plan Map for Ewa .................. 137
Figure 39. Oahu Zoning Map for Ewa ........................... 138
Figure 40. Ewa Beach Flood Insurance Zoning .................... 139
Figure 41. Ewa Beach - West End ............................ 142
Figure 42. Ewa Beach - West End ............................ 142
Figure 43. Seawalls at Ewa Beach ............................. 145
Figure 44. Houses at Ewa Beach ............................. 145
Figure 45. Kahala Beach Location ............................ 149
Figure 46. Hawaii Land Use District Map for Kahala ............... 150
Figure 47. Oahu Development Plan Map for Kahala ................ 151
Figure 48. Oahu Zoning Map for Kahala ........................ 152
Figure 49. Kahala Beach Flood Insurance Zoning .................. 153
Figure 50. Kahala Beach ................................... 155
Figure 51. Circulation Pattern ................................ 157
Figure 52. Kahala. Beach Nourishment Project ......... I ........... 158
Figure 53. Seawalls at Kahala ............................... 164

LIST OF TABLES

Table I - Published Components of Present Global Sea-level Rise ...... 33
Table 2 - Estimated Present Sea-Level Trend From Tide Gauge Records. 33
Table 3 - Hawaiian Sea Levels .............................. 37
Table 4 - Summary of Oahu Sand Resources (Moberly et al., 1975). 77
Table 5 - Renourishment Frequency Factors ..................... 83
Table 6 - Beach Recession Predicted Using The Bruun Rule ......... 86
Table 7 - Island Average Annual Beach Nourishment Requirements .... 88
Table 8 - Legal Status of Erosion Control Structures ............... 163
Table 9 - Breakdown of Costs for Kahala Beach Sand Replenishment ... 168
Table 10 - Benefits and Burdens to the Owners of Developed Land ...... 183
Table 11 - Benefits and Burdens to the Owners of Undeveloped Land .... 184
Table 12 - Benefits and Burdens to the County .................... 185
Table 13 - Benefits and Burdens to the State ..................... 186
Table 14 - Benefits and Burden to the Public . ...... .............. 186

xii

L INTRODUCTION

The beaches of Hawaii are precious natural features that provide recreational
opportunities, a healthy environment and uncompromising scenic beauty. Beaches
are also an economic asset since they form the heart of the number one industry
in the State,, tourism. Furthermore, offshore sand bars, beaches and dunes provide
important protection as a storm barrier to dissipate wave energy which may
otherwise damage inland property.

Migration and natural instability of the beach is due to the influence of
waves, currents, tides, storms, sea-level movements, and sand availability. These
natural forces have always altered and will continue to modify the beaches of the
State. It is vital that development and habitation of the coast is properly planned
with due consideration to the dynamic nature of the beach environment in order to
preserve this asset for future generations.

Human influences can lead to changes in a natural beach, In Hawaii, there
are many sections of the coast where shoreline development has not allowed the
beach to migrate. In an attempt to stabilize the shoreline, man's activities have lead
to the loss or degradation of miles of sandy beaches. In this report, an estimate has
been made of the total length of beaches on Oahu which have been degraded,
primarily due to hardening of the shoreline. A similar summary of previous studies
was performed for selected sites on the islands of Maui, Kauai and Hawaii.
Several examples are documented in figures to illustrate some of the more recent
coastal impacts. The estimates, preliminary assessments, and examples which are
contained in this study reflect significant deterioration of Hawaii's shoreline. Due
to sea-level rise and extensive shoreline hardening, beach loss is likely to
accelerate, unless there is a fundamental change in how the beach resource is
managed.

There are two major objectives of this report. First, to develop a
comprehensive and coordinated management plan for the State which will help
preserve pristine beaches while allowing for intelligent and safe development along
the shore. The most efficient and cost effective management strategy is to plan for
shoreline instability at the earliest stages of zoning when land-use policy is most
effective. Through proper planning, it is possible to produce the maximum long
term societal benefit from the beach resource.

The second objective is to address the erosion problem for sections of the
coast which are currently developed. For developed coastlines, the dual objective
of protecting private property rights while preserving the beach becomes
considerably more complex and costly. If a shoreline is developed but has not
been hardened, nontraditional alternatives such as sand replenishment, buried
revetments, and detached breakwaters may be appropriate in some localities. The
feasibility of these alternatives is dependent, in part, on the extent coastal
landowners, the counties and the State can cooperate through the establishment of
a Beach Management District (BMD).

For developed coastlines where the shoreline is hardened and the beach is
lost or severely degraded, efforts can be made to restore the beach. Given the
proper physical, social and economic conditions, it may be possible to recover lost
beaches by the relocation or removal of buildings or erosion control structures. In
this report, a strategy which offers economic incentives to the landowner forms the
basis of a voluntary progjam to move houses or erosion control structures inland.

. To the extent that it is scientifically, legally and economically possible,
alternatives in this report are formulated to address the concerns of the small
private landowner abutting the shoreline. Some of the recommendations in this
report may restrict the erosion control options of the homeowner. On the other
hand, new solutions are proposed which could be viewed as beneficial to the small
landowner. These include certain erosion control options which, from a practical
standpoint, were never available to the homeowner, but may be feasible through the
establishment of a BMD, where project costs are shared with the county, State and
possibly the Federal government. In sum, while certain options such as seawalls
and steep revetments will be restricted, the landowner will be given other
alternatives to protect private property.

All land use options developed in this report are designed to be within
constitutional limits. Legal safeguards are built into all land use proposals,
including provisions for hardship and the preservation of buildable area for all
zoning recommendations (i.e. retention of "economically viable use"). Many of the
strategies in this report were modeled after existing regulation in other coastal
states. Some of the more strict coastal regulations have had specific provisions
challenged by landowners and have survived legal scrutiny. The options in this
report were modified to be more sympathetic to the concerns of the small coastal
landowner.

Beach management options developed in this report can be grouped into
three broad categories:

1. Artificial -Beach Nourishment - The section on sand replenishment
discusses the concept, planning, sand resources, monitoring, maintenance, effect of
sea-level rise, structures associated with nourislimentl and recommendations.

2. Structural Options - This category includes seawalls, buried revetments,
detached breakwaters and recommendations.

3. RegglatoKy Measures - Regulatory measures include zoning, voluntary
relocation programs, Federal flood insurance programs, and the development of
Beach Management Districts (BMDs).

While some technical aspects of sand replenishment, breakwaters, and other
alternatives have been reviewed in numerous coastal reports (see e.g., Edward K.
Noda & Assoc., 1989), there are practical obstacles associated with some of the
options which prevent their use by the coastal landowner. Many of the obstacles,
such as cost and permitting, can be overcome by the establishment of a BMD.
Thus, the BMD is a land use option which would facilitate the implementation of
other structural and nonstructural measures.

This report has been organized into twelve main chapters. In Chapter II,
efforts are made to understand the magnitude and causes of past beach loss, to
predict the extent and causes of future loss in the State, and to describe the
potential problems from future sea-level movements. Before management plans can
be formulated, it is necessary to define the problem. It should be known for
instance, if beach degradation is confined to a few small sites or is widespread
throughout the islands. In addition, the effects of a continued or accelerated rise
in sea-level on the beach, the inland property, or on various types of erosion
control measures should be reviewed. In Chapter III, private and public property
rights in the shoreline are addressed. Since many of the proposals in this report
may affect public and private groups, it is important to review the rights and duties
of each party. In Chapter IV, strategies are discussed which were utilized in the
formulation of structural, non-structural and regulatory options. These strategies
include the formation of beach dl stricts, the use of economic mechanisms in beach
management, the enforcement of existing regulations, the streamlining of the
regulatory process and offsetting burdens with benefits. In Chapter V, the concept

of the Beach Management District (BMD) and the different permutations of this
regulatory tool are discussed. Obstacles to the implementation of BMI)s are
addressed and solutions are proposed. In Chapter VI, various nonstructural and
structural options are reviewed. The review of these options centers on how they
would be implemented within the BMD concept. Chapter VII deals with the issue
of financing the various beach management options. A scheme with shared cost
by the landowner, county, State and Federal government is proposed. A shoreline
property transfer tax similar to the tax in place in parts of Massachusetts is also
discussed. In Chapter VIII, other regulatory options which can be implemented
separately from BMDs are reviewed. These include a discussion on a voluntary
relocation program based on economic incentives, and the use of zoning to address
beach instability for large parcels of undeveloped land. In Chapter IX, it is
recommended that a new Division of State Beaches is established to administer and
implement BMI)s and other programs suggested in this report. In Chapter X,
efforts are made to apply the concepts developed in this report to Ewa Beach and
Kahala Beach. In Chapters XI and XII, there are recommendations for improved
beach management and guidelines for the implementation of these
recommendations.

11. PROTECTING HAWAH'S SHORELINE

During the 1991 legislative session, House Bill 893 proposed the
establishment of Shoreline Stabilization Districts,- and an extension of the shoreline
setback to 150 feet in non-urban districts for new lots. Many of the
recommendations in the house bill were taken from the 1991 report,
Recommendations For Improving The Hawaii Coastal Zone Management Program,
in realization that the Hawaii shoreline may need additional protection from current
activities. This bill was supported by the Office of State Planning, the Coastal
Zone Management Program, and the planning departments of Maui and Hawaii
counties.

Many comments were received on the house bill, both favorable and
unfavorable. Objections to the bill centered on the questionable need for additional
and extensive coastal regulation. Some commentators felt that the present system
of regulation appeared to work well within the counties. Others felt that there was
no compelling reason for additional controls, and that the shoreline of the State was
adequately protected.

This document reports that the beaches of the State do need additional
protection. In this study, changes will be discussed for how the Hawaii shoreline
is managed. Questions may be raised on the need for more regulation, additional
procedures or a new government agency. However, it is believed that the current
weight of scientific evidence warrants a change in shoreline management.

Two comments should be made regarding additional regulation of the
shoreline. First, significant degradation of the State's beaches has been identified.
This problem will not go away, and in fact, is expected to accelerate. Before
judgment is rendered on the proposals in this report, the reader should be aware of
the extent of the erosion problem, the impact on the State's shoreline and
projections for future change, assuming no action is taken. Second, it may be
possible to coordinate the regulatory process so that even with the addition of new
regulatory controls, there will be fewer regulatory hurdles. In this report, there is
a discussion on coordination of the regulatory process.

A. Beach Degradation on Oahu

Analyses of the earliest air photos for Oahu indicate that between 1928 and

1980, beach resources have been steadily lost from hardening of the shoreline
(Hwang, 1981). Along the windward coast highway near Kualoa for example, the
beach disappeared during the 1928 to 1978 period due to the combined effects of
a series of groins and vertical seawalls. Between 1949 and 1975, wave reflection
off a vertical wall contributed to the loss of beach at Swanzy Beach Park. Over
the same 26-year period, Laniloa Beach was degraded by the steady erosion of the
shoreline and the stabilization of the backshore with boulder piles and revetrnent.
Between 1949 and 1980, the beach at Bellows, located at the north end of the
Waimahalo littoral cell, has narrowed or disappeared in front of a sloping stone
revetment. In Hwang (1981), it was noted that seawalls, revetments and boulder
piles had caused the total length of recreational beaches on the island to steadily
decline over the 1949 to 1980 period. The latest date of aerial photographic
coverage for the 1981 study varied with each beach, but was generally from 1975
to 1980.

In the last twelve to seventeen years, the pace of beachloss and degradation
has not only continued, it appears to have accelerated. Since the 1975 to 1980
period, over two miles of combined beach have been lost at Iroquois Point, and
Kahala on the south shore; and at Lanikai, Punaluu, and Mahie Point on the
windward coast (Fig. 1). These recent changes are described in the following
paragraphs.

1. Iroguois Point - (Fig. 2). Between 1928 and 1967 the vegetation line at
Iroquois Point receded by as much as 140 feet. Over a similar period the water
line receded -by about 150 feet. Although there has been chronic erosion and -
significant inland migration of the shoreline,, the 1967 aerial photograph documents
a wide beach. The 1967 photo of Iroquois Point illustrates the general rule that a
beach migrating inland in its natural state doesn't wash away but simply shifts
position. The beach width remains relatively constant if there is no vertical inland
barrier.

During the 1967 to 1990 period, continued migration of the shoreline
threatened to undermine several houses. The 1990 aerial photo shows that after the
shoreline was stabilized with bulkheads and stone revetments, the beach was lost
along an 800 foot stretch.

2. Kahala - (Fig. 3). Over the 1949 to 1988 period, the vegetation line and
water line at the southwest end of Kahala was relatively stable, in part due to the

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Figure 2. Iroquois Point, Oahu. During the 39 year period prior to 1967, the vegetation line and
water line at Keahi Point migrated inland approximately 140 feet. Despite the chronic erosion,
the unstabilized beach in 1967 had recreational value. The 1990 photo shows the impact on the
beach from continued inland migration and stabilization of the shoreline with bulkheads, seawalls
and revetments.

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IF
igure 33 Kahala Beach- Oahu file west e-nd of Kaliala Beach has been characterized by relative
stability Nevertheless, nimor flUCALianons in tile position of the shoreline ,@aUsed homeowners
to hardell tile cmm 11%, 1 Q00, 111tich of, tile wit row hoach at Kflmh xv:i@ lost in @:(,,,ixvalls and

dissipation of wave energy by a shallow fringing reef approximately 500 to 1,000
feet offshore (Sea Engineering Inc., 1988). In addition, Black Point may block
some wave energy from the west-southwest. Although the shoreline at Kahala is
relatively stable, the homeowners have hardened the shoreline with seawalls and
revetmdnts. A comparison of the 1975 and 1990 aerial photos reveals that a
narrow beach was lost along 2,200 feet of the Kahala shoreline.

It is important to differentiate between the examples at Kahala and Iroquois
Point. While Iroquois Point has experienced chronic erosion, Kahala Beach has
been relatively stable. Nevertheless, beaches were lost at both sites. The Kahala
example demonstrates that even beaches that have been relatively stable for a long
period can disappear once seawalls or revetments exert sufficient influence on
nearshore sediment transportation. In fact, most of the beaches on Oahu that have
been lost or impacted by hardening of the shoreline do not have a long-term history
of chronic erosion.

3. Northwest Lanikai - (Fig. 4). From 1950 to 1975, the vegetation line at
northwest Lanikai experienced minor fluctuations in position of about 15 feet. The
1975 photo indicates that these fluctuations were insufficient to spur homeowners
to construct seawalls or revetments. Beginning in the late 1970's and early 1980's,
however, erosion along a 1,500 stretch threatened several houses and resulted in the
construction of seawalls and revetments. The 1990 aerial photograph shows the
impact on the beach from these hardened structures. Although there is a narrow
beach fronting the seawalls on the 1990 photograph, field visits indicate there are
numerous times of the year where the beach is entirely lost. Studies indicate that
wave reflection off the seawalls or revetments may inhibit sand deposition on this
coast. (Sea Engineering, Inc., 1988, Edward K. Noda & Assoc., 1989).

4. Southeast Lanikai - (Fig. 5). Between 1961 and 1971 the vegetation line
at the southeast end of Lanikai advanced seaward by as much as 139 feet. Some
of the accretion -w.as lost during the 1971 to 1975 period. On the 1975 aerial
photograph, there is a wide beach at the south end of Lanikai. Between 1975 and
1988, the vegetation line receded by as much as 84 feet (Sea Engineering, Inc.,
1988). The 1990 aerial photograph, shows that what was once a wide recreational
beach in 1975 has been-16st along a' '1,800 to 2,000 foot span of seawalls and
revetments. Numerous field checks to southeast Lanikai indicate that the beach
loss along this sector is more persistent than at the northwest end of Lanikal.

. .... ........ .. . . ....
Northwest Lq.nikqi:J
A p i 1 1. 3,,.:1:9 7 5:

Alala
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0 200 400 ft

Northwest Lanikai
November 11, 1990

Alala We
Point
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0 200 400 It

Figure 4. Northwest Lanikai, Oahu. Prior to 1975 the beach at Lanikai had a history of minor,
alternating erosion and accretion. During the late 1970's and early 1980's, pronounced erosion
spurred homeowners to stabilize the shoreline. The 1990 aerial photograph shows seawalls and
revetments along the shore, a narrowed beach, and the exposure of beach rock towards Alala
Point.

aximum:
Acdre'tion Point-.-, -

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Figure 5. Southeast Lanikai, Oahu. Prior to 1971 most of the southeast end of Lanjkai
experienced accretion- The accretion trend was reversed in the I 970's. Hardening of the
shoreline in response to severe erosion has led to the disappearance of the recreational beach
The 1990 photo. was taken late in the day, and shadows from trees are in the water-

5. Punaluq - (Fig. 6). The residential section to the northwest of Makalii
Point has been either stable or accreting during the period from 1949 to 1975. In
some sectors the vegetation line advanced seaward 63 feet (Hwang, 1981).
Between 1975 and 1988 the accretionary trend reversed and much of Punaluu
receded by as much as 58 feet (Sea Engineering, Inc., 1988). The 1990 aerial
photograph shows that approximately 1,200 feet of sandy shoreline has been lost
to the northwest of Makalii Point along a uniformly constructed revetinent. The
losses at Punaluu. demonstrate that even if adjacent property owners cooperate to
stabilize the shoreline with well constructed, uniform structures that have consistent
aligninent, the beach may still be lost. To the far south of Makalii Point the beach
has narrowed or has been lost along a 1,600 foot stretch. Some of the. negative
impacts along this stretch occurred before 1975.
6. Mahie Point to Makaua Beach Park'- (Fig. 7). It is along the windward
coast where the most extensive shoreline degradation has occurred. The reach from
Mahie Point to Makaua Beach Park is a typical example of the impacts. The beach
as shown on the 1975 aerial photograph has narrowed, and in many places
disappeared by 1990 along a 2,500 foot stretch of armored shoreline.

SUMMM

A preliminary estimate, or reconnaissance, was made on the island of Oahu
to determine the length of beaches that have been lost or degraded. In this report,
beach loss and beach degradation are grouped into one category. In- many
instances, it is not possible to differentiate between the two since there is a
continuum between the conditions. True beach loss would be the presence of no
beach seaward of an erosion control structure during mean lower low water for all
seasons of the year. While many shoreline sectors are believed to fit within these
parameters (e.g., portions of southeast Lanikai), it was beyond the scope of this
report to confirm these conditions. Beach degradation is defined as the condition
where the beach- has narrowed sufficiently so that some time during the year,
recreational use is denied or access along the shore is blocked (e.g., sections of
Mokuleia Beach on the north shore during the winter, or sections of Laniloa Beach
on the windward coast).

For Oahu, the length of coast where the beach was lost or recreational use
was degraded was estimated from the following sources of information:

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1) Beach Changes on Oahu as Revealed by Aerial Photographs
(Hwang, 198 1).

2) Oahu Shoreline Study: Part I Data on Beach Changes (1988)
(Sea Engineering Inc., 1999).

3) A set of aerial photographs taken of the Oahu coastline on November
11, 1990, by the R.M. Towill Company.

4) Field checks at specific locations that have been impacted.

A map of the island of Oahu (Fig. 8), shows the location of shorelines that
have experienced degradation. It is estimated that 8 to 9 miles of beach on Oahu
have either disappeared, or have narrowed to the point where recreational use is
temporarily denied. The total length of beaches studied in the 1981 Oahu report
was approximately 60 miles. Therefore, the length of coast that has experienced
beach loss or degradation is almost 15% of the total length of beaches studied in
the 1981 Oahu report.

The above figures, do not include the loss of beaches due to stabilization at
Portlock, Waikiki or the west end of Diamond Head Road. In addition, the above
figures should be viewed as a first estimate subject to later revision since it was
beyond the scope of this report to field survey impacted shorelines.

Beach loss on the island of Oahu appears to have accelerated. Of the 8 to
9 miles of impacted beaches, approximately 4 to 4.5 miles of beach were severely
impacted or almost lost. Half of the severely impacted shorelines disappeared
between 1928 and 1975. The other half was lost between 1975 and 1990 (e.g.,
Punaluu, Mahie Point, Lanikai, Kahala, Iroquois Point).

B. Beach Degrad.ation.On The Outer Islands

The loss of beach resources is not confined to Oahu, but has occurred
throughout the other islands. The reader is referred to the 1991 aerial photographic
study for the islands of Kauai, Molokai, Lanai, Maui, and Hawaii (Makai Ocean
Engineering, Inc. and Sea Engineering, Inc., 1991; hereafter MOESE, 1991). This
valuable study clearly documents beach erosion and accretion trends by tracking
historical movements of the vegetation line. More such documentation is needed,

21*
45'
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BEACH DEGRADATION
-A.
Sunset awela ON OAHU
Kahuku
..........
Beach

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Waimea Laie Beaches lost or use
temporarily denied

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1580 15, w 1580 00' 158' 45'

Figure 8. Beach Degradation on Oahu.

both to fill in the coastal segments not covered in MOESE (1991), and to establish
continuous erosion and accretion trends rather than at selected transect locations.

A reconnaissance of selected beaches on the outer islands revealed that
diminished recreational use, beach loss, beach narrowing, and preconditioning for
future beach degradation are significant problems on Hawaii, Maui, and Kauai.
These impacts are clearly associated with a wide-spread trend towards shoreline
hardening. Due to the proliferation of stabilization structures in the backbeach
area, and the continuing rise of sea level, beach loss and degradation is expected
to accelerate in the future. Beach degradation will accelerate more rapidly if the
present rate of sea-level rise remains constant. In the event of accelerated sea-level
rise, as projected for the next several decades by numerous researchers, beach
degradation in the State will accelerate to a critical level, threatening beach
resources on a State-wide scale.

1. Hawaii - The island of Hawaii lacks the extensive system of beaches that
characterize other islands in the State. This is because Hawaii is geologically
younger, a condition typified by shear cliffs, poor reef development, and rapid
subsidence of the island. Without the low-lying gentle coastal plains and the
shallow offshore platform which are found on more mature islands, it has not been
possible for extensive reef tracts to develop on parts of the island's coast. Since
reefs and reef-dwelling organisms are the principal source of carbonate beach sand,
there are fewer beaches on the Big Island. This condition makes beach degradation
all the more critical.

With the exception of small pocket beaches located at river mouths, and
where lava flows have been particulated to form black sand beaches, the North
Kohala, Harnakua, and Puna Districts are characterized by a general lack of natural
beaches. The few beach systems in these regions have never been analyzed for
long-term erosion/accretion trends and no data exist to allow an assessment of the
extent of degradation.

In the town of Hilo, the shoreline of Hilo Harbor is. stabilized (Fig. 9). Due
to the construction of a stone revetment to stop the erosion of water-front lands and
as a deterrent to the tsunami hazard, as much as I mile of beach has been lost. A
rapid relative sea-level rise on the Hilo coast of over 1.5 in/decade, has caused the
volcanic sand beach to migrate quickly landward. When the rising water reached
the revetment, beach migration ceased, and beach erosion accelerated to the point

Figure 9- TI'le stone revetment at Hilo Harbor, Hawaii. Here the relative sea-level rise exceeds
1,5 inches/decade, Hardening, of this shoreline has forced the loss of the beach to protect the
adjacent lands.

M, .,'z

*W7 1714
7,

Figure 10. Kona Coast of Hawaii. This artificially steepened beach on the Kona coast of.1-lawall
enhances the tendency for sand to move offshore, acceleratin- erosion. The oversteepening ofthis
beach increases wave energ on the beachface, accompanied by high velocity surgin- '11 tile.
P -, I
swash zone. Note the freshwater pond and the landscaped ve-getation on the back of the beach

I Q

where today the water laps against the stone face of the wall.

On the leeward side of Hawaii, analysis of historical movements of the
vegetation line on 29 beach transects in the South Kohala and North Kona Districts
(MOESE, 1991) revealed that since about 1950, 17 sites (59%) are eroding. The
average rate for the eroding sites is -0.6 ft/yr, and the average rate for the accreting
or stable sites is 0.35 ft/yr. Rates of vegetation line movement were extrapolated
to the year 2018 for these locations, and the probability for successful prediction,
relative to a random occurrence, was calculated in each case. In several cases the
standard deviation of the extrapolated vegetation line was high, indicating that the
extrapolation has a low predictive capability. These are often situations where
beach behavior is cyclic, or where sudden beach changes have occurred and may
not represent long-term trends. As a group, the eroding sites average 18 ft of
recession by the year 2018 and the accreting sites average about I I ft (relative to
1988). The average trend of all sites studied is to erode at a rate of -0.2 ft/yr, and
to recede an average 6 ft by the year 2018.

While these figures indicate a state of regional beach erosion for the South
Kohala and North Kona District coasts, they do not reflect factors and processes
at individual beaches. For instance, beaches associated with resorts along this coast
are frequently artificially nourished, and the beachface is often artificially steepened
(Fig. 10), a procedure known as "beach scraping". Beach scraping should be
discouraged since a steeper beach tends to reflect, rather than dissipate, wave
energy. Wave reflection enhances erosion by promoting the movement of sand
away from the beach. The steeper beachface also increases the velocity of the
backwash, and the general movement of sand towards the foot of the steep slope.
In. addition to beach scraping, the area behind the active beach is often landscaped
and maintained so that the vegetation line no longer reflects natural processes of
beach change. In the future, our understanding of the beach will have to rely on
profile monitoring and field surveys in these areas. In areas that are landscaped,
the vegetation line is no longer a valid indicator of erosion or accretion trends. In
fact these errors -are probably already incorporated to some extent in the MOESE
(1991) report.

Finally, it was made clear in field visits to Hawaiian beaches that many are
preconditioned for degradation and eventual beach loss because of the presence of
protective structures immediately landward of the sandy beach. Although this
factor is not as prevalent on Hawaii as on Maui or Oahu, preconditioning was

obs erved at several resort beaches. Considering the high relative rate of sea-level
rise on Hawaii, if these beaches are not nourished or otherwise maintained on a
regular schedule, or if existing stabilization structures are not removed, they will
eventually be lost as the waterline migrates toward the armored upland.

2. Maui - On Maui, beach degradation in many locations has reached a
critical stage because of the rapid relative sea-level rise there (nearly I in/decade)
and the proliferation of shoreline stabilization structures (Fig. 11). In the MOESE
1991 report, 63 of 102 transects analyzed (62%) were found to be eroding, 25
(24.5%) were accreting, and the remainder had been stabilized by some form of
armoring. In nearly all cases seawall or revetment construction followed a period
of significant beach erosion, and resulted in beach loss. Together, erosion and
hardening characterized over 75% of the studied shoreline. The eroding sites
averaged -1.25 ft/yr, and the accreting sites averaged 1.08 ft/yr. Projections to the
year 2018 suggest that the eroding sites will recede an average 36.4 ft, and the
accreting sites will average nearly 24 ft (relative to 1988). The average trend of
all nonstabilized sites is to erode at a rate of -0.6 ft/yr, and to recede an average
of 18.8 ft-. by 2018.

Maui is notable for the extensive beach loss, beach narrowing, and
widespread use of stabilization structures, especially along the west Maalaea Bay
coast and the reach from North Kihei to South Kamaole (Fig. 12). Other problem
areas include portions of the Kahului coast and much of the shoreline between
Lahaina and Kapalua. The tendency to stabilize receding shorelines on Maui has
led not only to existing degradation, but also to the preconditioning of much of the
coast to accelerated beach loss in the future. A number of fine wide beaches abut
revetments. and seawalls that are often fully vegetated. These structures were
originally placed out of the reach of fairweather wave runup. With continued
sea-level rise they will soon begin to reflect the wave energy leading to
offshore directed sand transport, beach erosion, and eventual beach loss. Field
visits identified a number of protective structures whose vegetative cover has
recently been damaged by wave action. At these sites, the process of beach
degradation has already begun. These locations show evidence of beach narrowing,
deep beach cusp development and channeling, and accelerated erosion.

Ironically, there are a number of sites on Maui where beach loss has
occurred on stabilized shorelines that are not protecting any upland development.
For instance Kalama "Beach" Park is protected by over 3000 ft. of stone revetment

Figure 11. West Maalaea Bay, t%,IaU]r The west Maalaea Bay shoreline, Maul, formerly a
calcareous sand beach. Erosion followed the construction of the Maalaea Bay Harbor Jetty in
1952 (beyond the photo), and now 2400 ft of coast is hardened with revetments and seawalls.

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jar,

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Figure 12. A vegetated revetment on the highway near KIhel, Maul. Notice the deep indentation
in the coast from a lack of sand due to the groln Just to the north. This small beach is one of
many that are preconditioned for loss A ve-etated revetinent protects the highway. AlthOL11111 the
beach exhibits si2ns of accelerated eiosion, the revetment has stabilized the vegetation line and
future aerial photographic analysis will not record the degradation. This beach will be lost when
waves begin to interact with the revetment on a reolular basis. This may occur followino the next
larae storm- ot ac continued sea-lovei r1se drives the waterline inland

that has led to the total loss of the beach (Fig. 13). Yet in places, the nearest
upland development is almost 1,000 ft away from the revetment. The erosion at
Kalama has produced accelerated beach loss downdrift (north) of the revetment on
neighboring Waimahaihai Beach (Fig. 14), where a number of seawalls are erected
on private properties. On unstabilized properties, 3 ft high erosional scarps mark
the recession of the shore resulting from the loss of the area's sand supply. These
will undoubtedly be the next sites for stabilization as the erosion proceeds landward
and houses become threatened. As seawalls and revetments, of various types spring
up along this residential beach, the zone of enhanced erosion will be pushed along
to the north. In fact, this is a "domino effect" resulting from the Kalama
revetment, and exacerbated by the high rate of relative sea-level rise, which has the
potential to cause a migrating beach loss problem reaching north along the entire
Kihei coast.

Taken to the limit, a long stretch of stabilized and beachless coast can result
in the complete termination of the sand supply. For instance, on the northwest
coast of Maui at Honokowai (north of Lahaina), there is over a mile of stabilized
shoreline that has no beach (Fig. 15). Immediately to the north of this section is
Honokowai Beach Park, which is not stabilized, but is experiencing enhanced
erosion. It is apparent that the extensive hardening of the coast to the south has
prevented sand deposition at the beach park because the former sand source has
been replaced by a line of seawalls. Without the longshore delivery of sand, the
beach at Honokowai has no natural replenishment mechanism and over time it has
eroded away. Today, the shoreline at Honokowai Beach Park is the location' of
coral rubble, cinder blocks, dirt, and a 2 ft erosional scarp marking the recession
of the coast.

It is interesting to note that in the case of Kalama Park, the action of Maui
county led to downdrift impacts on private property. In the case of Honokowal,
the action of private landowners led to impacts on Maui county park land.

Perhaps most telling is the case of shoreline stabilization along the
Honoapiilani Highway in the area of Punahoa beach, south of Lahaina. There,
beach recession threatens to undermine the highway. To protect the highway, a
crude set of concrete barriers (the type used as highway lane dividers), and an
expensive revetment have been installed to stop the recession (Fig. 16). A formerly
wide and healthy beach has been lost in the process. There is no development
along this shoreline, only the two lane highway is threatened by the erosion.

Figure 13. Kalarna Beach Park, Maul. Kalama Beach Park has had a long history of erosion.
Here a 3000 ft sloping stone revetment designed to encourage sand accretion was built in the
early 1970's. Today the former beach is gone, and the par k is protected from further erosion.

A7
it

Figure 14. Walmahathal Beach, Maul. Walmahathal Beach is immediately north of Kalama Park.
Erosion caused by th eKalama revetment has led to the construction of 2400 ft of seawalls and
revetments protecting private residences. Severe erosion characterizes the coast north of these
structures, More than I mile of continuous sandy beach has been lost here in the last 15 years

2 4

p
vza

Figure 15. Honokowal Beach Park, north of Lahaina, Maul. Vertical seawalls extend along, most
of the 6,000 ft of coast downdrift (south) of this park. An erosion problem in the 1970's lead to
the construction of the seawalls to prevent the damage or loss of beach front condominiums and
resort hotels. Development of the shoreline occurred during a phase of temporary accretion, most
buildings were placed 40 ft from the vegetation line at the time of construction. With the onset
of sustained erosion, the setback proved inadequate. Now over 2 miles of former sandy beach is
lost because of shoreline hardening, on this coast and immediatelv to the north.

ip-

F 1 g u r e16. PUnahoa Beach South of Lallaina, Maui. Severe erosion threatens the hI,-,hwav. now
protected with combined ternporary and peirrianent structures. Continued sea-le@!el rise will lead
to more permanent structures and eventual [)each IOSS 11OTe Instead the hlghway could be
ielocated

Mauka of the road is a flat coastal terrace perhaps a mile wide. Rather than move
the highway to the foot of the hills at the back of the terrace and make a beach
park where the shoreline is receding, the beach is being sacrificed in the interest
of protecting the highway. The crude barriers presently protecting the road will
soon be inadequate and need to be replaced by a larger and longer stone revetment,
at a cost of millions, perhaps tens of millions of dollars. Sand delivery to
neighboring beaches will diminish and erosion will accelerate to the north of the
site. Neighboring beaches will be impacted, and the structure will have to be
extended to protect the road there. Very soon the size and cost of the protection
will vastly exceed the cost to protect the road. Early planning could instead have
created a beach park that would have relieved the crowding at parks near Lahaina
and along Maalaea Bay, provided visitors and inhabitants with an additional
recreational resource, preserved the State conservation land that is the beach, and
saved enormous public funds.

3. Kauai - On Kauai, the MOESE (1991) report identified extensive
stabilization and erosion along certain sites on the south and east coasts of the
island. In the area from Hanamaulu to Kealia (makai of Lihue, on Kauai's east
coast), 25 of the 42 sites studied (60%) are either stabilized or eroding. The
average rate of erosion is -0.61 ft/yr, and at these sites the coast is projected to
retreat an average of 19 ft by 2018. Other sections of the Kauai coast not covered
in the MOESE report are also eroding, but many are not. The generally
undeveloped nature of the north and west coasts show net accretion trends over the
period studied, and erosion is usually confined to dynamic river mouth movement
or natural fluctuations in the coastal sand budget. In every case where erosion is
occurring without the influence of upland development or beach stabilization, the
beach has maintained its width and sand supply even while retreating landward.

There are a number of erosion management problems on Kauai. At Kikiaola
Harbor (Fig. 17) on the south coast, a massive jetty has interrupted the natural
littoral drift causing an erosional offset in the coast a mile long and 100 ft wide.
The jetty is being flanked by this erosion, and temporary extensions have been
emplaced to keep the jetty attached to the shore. A cemetery is threatened by the
erosion. The dune protecting it is on the verge of being breached by erosion which
is occurring at over 2 ft/yr. Despite the massive erosion here, the beach is still
wide and sand-rich, offering excellent recreational opportunities because the
shoreline is not stabilized. If this segment is hardened, more than I mile of beach
will be lost.

_44

F ig ure 17. Kikiaola Harbor, Kauai. The erosional offset at Kikiaola Harbor, Kauai. Here, Jetties
used in the construction of the harbor, have interrupted the lon-shore pattern of sand movement
and this downdrift offset in the coast has developed. The erosion rate exceeds 2 ft/yr; note the
stumped and fallen trees and the eroded dune face, yet because the shoreline is not stabilized the
beach is still wide and has recreational value despite the high erosion rate.

H el
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Figure M The Residential Beach at Walpoll, Kauai Jetties both north and south of this segment
block tile longshore sand supply in the winter and sunirner, respectively As a result the shoreline
erodes ai I @, 'ft/vr. Previous erosion rates were hi-lier (4 3 ft/N!r) but-the beach Is mostly -one
now and a earthen scarp is erodin- tile resIdential frontaue road. This stretch is likely to he
haidentf,d snon. pie%'enting any possibilli\ Of beach recoverv
ilk

At Waipoli Beach (Fig. 18), north of Lihue, severe erosion has led residents
to construct rubble mounds and to dump boulders as temporary barriers in order to
protect the small frontage road which is the only access they have to their homes.
A 5 ft erosional scarp threatens to undercut the road. Roots are exposed and trees
are ready to fall as the scarp continues to develop. The beach is gone, and beach
rock tends to channelize water at the base of the scarp exacerbating the erosion.
Immediately to the north and south are stone jetties extending 100 to 300 ft
offshore. These interrupt the seasonal littoral sand drift which would otherwise
nourish this former beach. Large waves in the winter months generally come from
the north, hitting the coast at an angle and driving a longshore current that
transports sand to beaches in the south. The jetties at the mouth of the Waikaea
Canal prevent this sand from reaching the residential beach at Waipoli. In the
summer months, large waves come from the south, and drive a littoral drift of sand
that is interrupted by jetties stabilizing a small drainage canal to the south of
Waipoli Beach. Although the seasonal littoral sand supply to Waipoli residential
beach is blocked by these jetties, the wave energy is not. As a result, winter waves
from the north take sand away from the site and transport it to the south, and
summer waves from the south transport the little remaining sand to the north.
Broad pockets of accumulated sand immediately inside the neighboring jetties
testify to this process. The residential coast is serving as an unreplenished source
of sand to the areas north and south. Eventual stabilization of this coast will
prevent the potential return of the beach should one of the jetties be removed..

Other problems can be found as well. At Kapaa Beach Park, reef dredging
has created a deep hole offshore that traps all sand otherwise destined fo r the
beach. Along the park shoreline the beach has been lost, and large ironwood trees
are being undercut by an erosional scarp. At the Wailua Golf Course, a 3500 ft
stone revetment has been built to protect the fairway and several greens. The
beach in front of the structure has narrowed considerably in the 5 years since
protection was established and what was formerly a 3/4 mile-long, wide and
dynamic beach is now degraded, and will soon disappear. The impacted littoral
dnift is likely to f6ad to chronic erosion problems both north and south of the golf
course where no erosion problem presently exists.

These are typical examples of beach degradation that are found on Kauai, as
well as on the other Hawaiian Islands. Many of these cases of beach degradation
and loss could have been avoided by informed planning based on a knowledge of
littoral processes, rates of relative sea-level rise, and the long-term implications of

shoreline stabilization under rising sea level.

C. Global and Local Sea-Level Rise

1. Global Sea Level. Perhaps few scientific issues in recent decades have
been so intensely examined on an international level as the predictions of global
climatic warming and sea-level rise in the 21" century. These predictions are based
on our understanding of atmospheric processes involving heat-trapping compounds
("greenhouse gases") that prevent the infrared radiation heat of the earth from
escaping to space (called the "greenhouse effect"). Because of the build-up of
these gases in our atmosphere, computer-based global circulation models have
predicted climatic warming in the 21" century. The wonisome aspect of this
prediction is its factual basis in the observed increase of carbon dioxide (C02, an
important greenhouse gas) and other heat-trapping gases in the atmosphere (Fig.
19). However, scientists still have difficulty predicting- 1) what exact effect the
increase of greenhouse gases may have on the global climate; 2) what effect global
warming may have on localized temperature and humidity patterns; and 3) the
exact magnitude of sea-level movements to be expected under a warming climate.

To date, the most reliable scientific consensus on potential global climate
change in the next century is the assessment of the Intergovernmental Panel on
Climate Change (IPCC, 1990). The IPCC report is the product of over 200
international climate researchers working under the auspices of the United Nations
and the World Meteorological Organization. Among their findings is a prediction
for accelerated sea-level rise through next century (Fig. 20). Their results agree
with estimates of other researchers (NRC, 1987; NRC, 1990a, 1990b) and have
generally -been accepted by members of the research and policy-making community.

In the IPCC report (1990), global mean sea level is projected to rise at an
average rate of about 2.36 in/decade (6 cm/decade) over the next century, with an
uncertainty range of 1. 18 to 3.94 in/decade (3 to 10 cm/decade). The projected rise
is about 7.9 in (20 cm) by the year 2030, and 25.6 in (65 em) by the end of the
next century.

Several factors affect sea level on the global scale, but four major effects are
attributed to global warming. These are, thermal expansion of ocean water,
changes in the Greenland and Antarctic ice sheets, and melting of mountain
glaciers. The best estimate of future sea-level trends in the IPCC model is

360

E
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320

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1700 1800 1900 2000

350

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1960 1970 1980 1990

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0 MP
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0.2

OA -
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YEAR

Figure 19. Intergovernmental Panel on Climate Change, 1990. The basis for predicting global
warming in the 21" century. Top: Atmospheric carbon dioxide has risen since the start of the
industrial revolution and the-large-scale burning of fossil fuels. Global annual emissions of C02
by fossil fuel burning and other industrial activities have increased annually by about 4% since
1860. These data are C02 content (parts per million by volume) of air bubbles trapped in ice that
was cored from the Antarctic ice sheet. Middle: Monthly average C02 concentration in parts per
'million of dry air observed continuously at Mauna Loa, Hawaii. The annual variations shown
are produced by the seasonal production (winter) and withdrawal (spring and summer) of carbon
dioxide by living organisms on land. Bottom: Global-mean combined land-air and sea-surface
temperatures, 1861-1989, relative to the average for the period 1951-80. This record is
controversial, but it shows a warming trend over the entire period, highlighted by pronounced
warming since the late 1970's. The record is the best estimate of global temperature change over
the last century or more. Is the warming real? Is it a natural climate fluctuation? Is it the
product of C02 build-up in the atmosphere and an enhanced greenhouse effect?

E
80
W BUSINESS
AS-USUAL
60

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-J 40 _."00 C.-M
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20.- SCENARIO D -
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cc 1980 20010 2020 2040 2060 2080 2100
A

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0

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FORCING STABILISED
W 10
IN 2030

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1980 2000 2020 2040 2060 2080 2100
YEAR

Figure 20. Projected Sea-Level Rise. Top: Sea-level rise projected by the IPCC (1990) between
1990 and 2100. The "business as usual" scenario is a model of sea level assuming uncurtailed
industrial emissions of greenhouse gases, a scenario currently being fulfilled by the U.S. Bottom:
According to calculations, even if production of greenhouse pollutants (greenhouse forcing)
increased no farther, there would still be a commitment to continuing sea-level rise for many
decades due to a delayed response of natural climate factors. If the increases in greenhouse gases
were to stop in 2030, sea-level would go on rising to 2100, by as much again as from 1990 to
2030.

composed mainly of positive contributions from thermal expansion of oceanic
surface waters, and melting of mountain glaciers. Future changes in the Greenland
and Antarctic ice sheets are poorly understood and heavily debated by researchers.

Attempts have been made to quantify the various components of global
sea-level change. The most widely accepted, published estimates include thermal
expansion estimated as a positive effect on global sea-level movement (0.08 to 0.24
in/decade; Wigley and Raper, 1989), and melting of mountain glaciers and small
ice caps estimated as a positive effect on global sea-level movement (0.08 to 0.28
in/decade; Meier, 1990). The nature of change in the Greenland ice sheet is
debated. One interpretation of satellite data suggests the ice sheet is thickening and
might be removing water from the oceans (Zwally, 1989). The Greenland ice sheet
is, nonetheless, estimated as contributing to sea-level rise at 0.03 to 0. 15 in/decade
(IPCC, 1990). Changes in the Antarctic ice sheet, which is considered to be
thickening, not melting, are thought to decrease the rate of global sea-level rise.
The Antarctic contribution is estimated as -0.08 to -0.24 in/decade (IPCC, 1990).
Two other factors that are not directly related to warming may affect global
sea-level movement. The first, reservoir impoundment of surface water for human
use, is estimated as a negative effect (427 in/decade; Chao, 1991). The second,
withdrawal of groundwater for human use and'eventual discharge into the oceans,
is estimated as a positive effect (0.03 in/decade; IPCC, 1990). The total net budget
for sea-level change based on these components is 0.03+/-0.32 in/decade (-0.29 to
0.35 in/decade, Table 1).

It is instructive to compare a compilation of the supposed components of
present global sea-level movement (429 to 0.35 in/decade, Table 1) to global
sea-level rise as actually recorded by tide gauges around the world (Table 2). As
Table 2 shows, a number of researchers have statistically analyzed long records
(>45 yr) of sea-level trends. Each estimate in Table 2 accounts for localized
effects such as crustal subsidence, and compaction of sediments under the gauging
station. These values (averaging 0.56+/-0.12 in/decade, Table 2) are measurements
of actual present sea-level movement recorded by tide gauges around the world.

The range of values in Table 2 (0.4+/-0.04 to 0.95+/-0.36 in/decade) reflect
differences in the technique of statistical analysis, and differences in the actual
c.j group of tide gauges used in each case.

Table I - Published Components of Present Global Sea-level Rise.
ISOURCE CONTRIBUTION
Thermal Expansion 0.08 to 0.24 in/decade
Mountain Glacier Wastage 0.08 to 0.28 in/decade

Greenland Ice Sheet 0.03 to 0.15 in/decade

Antarctic Ice Sheet -0.24 to -0.08 in/decade

Reservoir Impoundment -0.27 in/decade
[Groundwater Withdrawal 0.03 in/decade
-T-0.29 to 0.35 (0.03+/-0.32) in/decade
FTot; 71Net

Table 2 - Estimated Present Sea-Level Trends From Tide Gauge Records.
REFERENCE -TESTIMATE
Gornitz & Lebedeff, 1987 0.47+/-0.12 in/decade

0.4+/-0.04 in/decade

Barnett, 1988 0.45 in/decade
Peltier & Tushingham, 1989 0.95+/-0.36 in/decade
Trup n Wahr, 1990 0.69+/-0.05 in/decade
Douglas, 1991 0.44+/-0.04 in/decade
=Average Fo .56+/- 0.12 in/decade

Considering the lack of agreement between the observational data (tide
gauges, Table 2) and the theoretical data (components, Table 1) it is fair to state
that little quantitative understanding exists with regard to the global rate of
present-day sea4evel movement. It is generally accepted, however, that sea level

is presently rising on a global basis, and the best estimate of that rate is between
0.3 to 0.8 in/decade. If asked to pick a single rate, many experts would pick
between 0.4 and 0.6 in/decade. With this in mind,-me will adopt the average of
Table 2, 0.56+/-0.12 in/decade, as our estimate of global sea-level rise. Again, one
should keep in mind the lack of agreement between the measurements of
present-day sea-level change and the calculations of present-day sea-level change.

2. Hawaiian Sea-Levels. Although understanding of present-day global
sea-level movement is poor, we can have greater confidence in our understanding
of present-day local sea-level movement in the State of Hawaii. Because Hawaii
has a well maintained array of N.O.A.A. tide gauges that have been operational for
several decades, local sea-level trends on the main Hawaiian islands are well
documented (Fig. 21).

The Big Island is larger, and therefore heavier than the other islands.
Because of it's great mass, it causes the underlying earth's crust to flex downward
leading to island-wide sinking. This is called subsidence, and the Big Island is
subsiding so much that neighboring islands (Maui, Lanai, and Molokai) are thought
to be subsiding along with it. Sea-level movement on these islands then, is the
sum of global rise and island sinking. This is called submergence. Thus, the
relative rate of sea-level rise (or submergence) is higher at the southern islands than
for Oahu and Kauai, which are less affected by Big Island subsidence. Because of
this phenomenon, sea-level is rising fastest at Hawaii, a little slower at Maui, and
slower still at Oahu and Kauai. The tide gauge records (Fig. 21) support this
theory. The general pattern of sea-level movement in the State is controlled by
individual rates of island subsidence, superimposed on the *background global rate
(which can be assumed constant throughout the State).

As stated, we will assume that the present-day rate of global sea-level rise
is about 0.56 in/decade. We will use this number to calculate individual rates of
island subsidence. Following that, we will add island subsidence rates to the IPCC
(1990) projections for future global sea-level rise, in order to estimate future
submergence rates (relative sea-level rise) at Hawaii, Maui, Oahu, and Kauai. By
way of caution however, one has only to refer to Table II to see that there are as
many present-day global rates as there are attempts to define it, and so we proceed
with a warning to the reader that continuing research in the near future will
undoubtedly provide new numbers for global rates (though probably not greatly
different from our assumed average). As understanding of both present-day and

Nawiliwili Monthly Tide Level Honolulu Monthly Tide Level

E E
0.69�0.12 In/decade
72-- -FO.62�0.03 In/decade
>

70 -70

>
68 . ....... ......--
68

Cr.
1960 1970 1980 1990 1900 1920 1940 1960 1980
Year Year

Mokuoloe Monthly Tide Level Kahului Monthly Tide Level

E
0. 6 4 0. 13 1 7n/ d7e-c-a
72 7de I FO.97�0.09 in/decad7e. . .. ....... .... 72 73
>

M L
4) 70 - 70

Z
68 68

T
1960 1970 1980 1990 1950 1960 1970 1980 1990
Year Year

Hilo Monthly Tide Level Subsidence relative to Honolulu

E ---------
Ca
72 11.55�0.09 ini/decade@.....@ MOKUOLOE
-6 .... .. ........ 0.0
>
0.2
HAWILFWIU
0 KANULLq
0 70 - 0.4

------------ -- - - -
0.6
Z HILO
68 - . ... ..... .-
0.8
CO
1.0 .0

1950 1960 1970 1980 1990 0 100 200 300 400 Soo
Year Distance from Kilauea (km)

Figure 21. Local Sea-Level Trends. Local relative sea-level trends (submergence rates) in the
State of Hawaii from tide gauges (from Paul Wessel, University of Hawaii, Department of
Geology and Geophysics), MULU MOKUOLOE
ULL
q HAWILJWIU

future sea-level rates improves, our estimates should be revised. We refer the
reader to Emery and Aubrey (1991) for a comprehensive review of geologic and
oceanographic factors affecting tide gauge records, we also note their conclusion
that present global sea-level rise can only be bracketed between 0 and I in/decade.

A least-squares fit of tide gauge records (Fig. 21) shows that the rate of
sea-level rise in Hilo Harbor is 1.55+/-0.09 in/decade, and at Kahului on Maui it
is 0.97+/-0.09 in/decade (Paul Wessel, pers. comm.). Both of these are
considerably higher than the estimated rate of global sea-level rise. Honolulu, on
the island of Oahu, is thought to be generally free of the Big Island effects of
enhanced subsidence (beyond the flexure), which accounts for the much slower rate
of sea-level rise there, about 0.62+/-0.03 in/decade. On Coconut Island (Mokuoloe)
in Kaneohe Bay, Oahu, a tide gauge records a rate of (0.64+/-0.13 in/decade). In
Nawiliwili Harbor on Kauai, the tide gauge records a similar rate of about
0.69+/-0.12 in/decade (Paul Wessel, pers. comm.).

By subtracting our assumed present-day global rate (0.56+/-0.12 in/decade)
from island-specific submergence rates, we calculate the island-specific subsidence
rates. Hilo is subsiding at 0.99+/-0.21 in/decade, which is 64% of the total
submergence rate (Table 3). Likewise Maui, which is submerging at 0.97+/-0.09
in/decade, is subsiding at 0.41+/-0.21 in/decade (42%). Oahu is subsiding at
0.06+/-0.15 in/decade, and Kauai is subsiding at 0.13+/-0.24 in/decade. Let us
assume that the IPCC projection for accelerated sea-level rise in the next several
decades is correct. The Hawaiian islands will then submerge at 2.36+/-1.4
in/decade (future global sea-level rate) plus the island-specific subsidence trends we
have calculated. Accordingly, under the IPCC best estimate scenario, we can
expect sea-level on Hawaii and Maui to rise at an average rate of 3.35+/-1.61
in/decade and 2.77+/-1.61 in/decade respectively; and on Oahu and Kauai we can
expect rates of about 2.42+/-1.55 in/decade and 2.49+/-1.64 in/decade, respectively.

Tide gauges record alterations in sea-level position due to variations in
atmospheric pressure, winds, ocean currents, long-period tides, upland runoff,
vertical land movements, sediment compaction, groundwater withdrawal, and long
period meteorologic events such as the El Nino Southern Oscillation (Wyrtki, 1990;
Emery and Aubrey, 1991). While the net submergence values for each station are
averaged over more than 30 years of data, and thus tend to smooth these various
perturbations, as more data are collected the trends of these records are likely to
change somewhat.

Table 3 - Hawaiian Sea Levels.

STATION NET SUBSIDENCE RATE PROJECTED
SUBMERGENCE SUBMERGENCE

(fide gauge trend) (NET SUBMERGENCE (SUBSIDENCE RATE
minus assumed present plus assumed projected
sea-level rise of 0.56+/- sea-level rise of 2.36+/-
0.12 in/dec.) 1.4 in/dec.*)

Hilo 1.55+/-0.09 in/dec. 0.99+/-0.21 in/dec. 3.35+/-1.61 in/dec.

Kahului 0.97+/-0.09 in/dec. 0.41+/-0.21 in/dec. 2.77+/-1.61 in/dec.

Honolu u 0.62+/-0.03 in/dec. 0.06+/-0.15 in/dec. 2.42+/-1.55 in/dec.

Nawiliwill 0.69+/-0.12 in/dec. 0.13+/-0.24 in/dec. 2.49+/-1.64 in/dec.
*IPCC, 1990 best estimate scenario of future sea-level rise. See Wigley & Raper, 1992 for
revised IPCC estimates for sea-level rise, which fall within the range used in this report.

The range of error we attach to the projected (future) submergence rates, is
the sum of the standard deviation of the calculated tide gauge trend, the error of
the assumed rate of present sea-level rise, and the uncertainty of the projected rate
of future global sea-level rise (IPCC, 1990). Our first source of error is in the
assumed rate of global sea-level rise, 0.56+/-0.12 in/decade, which is probably
somewhere between 0.40 in/decade (Wyrtki, 1990) and 0.9 in/decade (Peltier and
Tushingham, 1989). Extrapolating from Table 2, we estimate a minimum
subsidence rate error for each island of +/-0.12 in/decade, plus the standard
deviation of the net submergence trend at each station. The projected submergence
rates assume a future rise of 2.36+/-1.4 in/decade, as given by the IPCC (1990).
We have added the subsidence rate error at each station to the projected
submergence rate error of +/-1.4 in/decade, to derive the minimum projected
submergence. rate error at each station.

From the above discussion, the following conclusions can be made.

1.) Discrepancies between estimates of the components of global sea-level rise, and
observed trends in the global array of tide gauge stations, are reminders that our
understanding of sea-level movements is primitive, and that projections of future
sea-level movements are likely equally primitive.

2.) Assuming that global sea level is rising at 0.56+/-0.12 in/decade, and that the
IPCC projection of future sea-level rise is correct (2.36+/-1.4 in/decade), if island
subsidence rates remain constant, we estimate that over the next century sea level
will rise an average of 3.35+/-1.61 'in/decade at the Big Island, 2.77+/-1.61
in/decade at Maui,, 2.42+/-1.55 in/decade at Oahu, and 2.49+/-1.*64 in/decade at
Kauai.

3.) In the event of accelerated sea-level rise, the observed genera I tendency for
beaches around the State to erode will be enhanced. Beaches that are presently
accreting are likely to begin eroding, those that are presently eroding will begin to
erode at accelerated rates.

4.) Accelerated erosion will be accompanied by accelerated shoreline recession.
This tendency for beaches to move inland will result in increased shoreline
stabilization, and increased interaction between stabilization structures and coastal
processes. This will lead to continued, and accelerated beach loss.

5.) In addition to beach loss, sand loss will become a problem of growing
magnitude. Sand loss will result from higher wave energy at the coast where
shorelines are stabilized and the tendency for sand to be carried offshore by rip
currents, reflected wave energy, and seaward-directed currents along the bottom.

6.) In the event of accelerated beach degradation, informed beach management will
require more detailed shoreline data. Historical photographic. shoreline analysis is
a valuable management tool, and its development and use in the State should
continue to be supported. But beach degradation can be difficult to fully quantify
because aerial photographic coverage can be spotty at sites, and it relies on
vegetation line movements rather than actual beach width. In developed areas,
vegetation growth is sometimes stabilized by landscaping and/or vegetated
stabilization structures. " In such areas the technique is no longer viable because
beach width changes will not be followed by vegetation changes. A more accurate
and detailed technique, which also supplies useful data for artificial beach
nourishment, is beach profile surveying. There is no substitute for periodic site
surveys to exactly document beach state. A joint State-wide system of
semi-decadal historical photographic shoreline analysis and quarterly beach and
nearshore profiling would provide critical monitoring data on erosion/accretion
trends. Beaches are one of the States most valuable environmental and economic
assets. With this data the State would optimize the effective management of its

beaches.

D. Prediction - Accelerated Beach Loss

All the major islands of Hawaii are experiencing erosion. In the MOESE
report, known erosion rates are used to predict the amount of shoreline. recession
by the year 2018. On Kauai, forty-one eroding beach sites are predicted to retreat
an average of nineteen feet by 2018; on Molokai, fifteen sites will retreat about
twenty-one feet; on Maui, sixty-three sites will retreat an average of thirty-six feet;
and on Hawaii, seventeen sites will retreat about eighteen feet. The number of
eroding beaches listed here reflects a survey of a fraction of the beaches on each
island. In addition, these calculations do not account for the possibility of
accelerated sea-level rise, which can be expected to worsen the problem.

In many cases the erosion is at a critical point where buildings, roadways,
and houses would be threatened without the protection of shoreline stabilization.
When the decision is made to stop the sea and protect the land with a seawall or
revetment,, beach loss may occur slowly, over decades. Land ownership may
change and people soon forget that there used to be a beach where now there is a
wall, By default, beach loss becomes an acceptable consequence of living on the
coast.

Beach loss or degradation has occurred for over 8 to 9 miles of beaches on
Oahu, 2.8 to 6 miles on Maui, I to 2 miles on Kauai, and I to 1.5 miles on Hawaii.
Although beach erosion is a common phenomenon for all the islands, the recurring
factor in beach loss is hardening of the shoreline, not persistent or chronic erosion.

Stabilization of the shoreline with seawalls and revetmehts can be the death
of beaches for several reasons. Solid structures on the beach reflect, rather than
absorb wave energy so that water returning seaward carries sand away from the
beach. This accelerates beach erosion. Also important is that the seawall or
revetment cuts off sand exchange between the dry sand beach and inland coastal
s
and sources, which are quite important on Hawaiian coasts. The backshore area
can be an important reservoir of sand to repair the beach after a storm or brief
erosion event. With increased wave reflection and a constricted, faster longshore
current, seawalls and revetrnents lead to a higher general energy level In the
nearshore environment. This prevents the deposition of sand and ultimately forces
sand to move offshore to deeper water. In addition, a lost or narrowed beach

represents. a loss of nourishing sand for all beaches in the longshore system.
Erosion can be initiated on neighboring sections of the coast, leading to the
construction of additional seawalls and revetments.
I

In spite of these processes, not all seawalls and revetments have led to the
loss of the beach. Very infrequently, some of the structures are not located in the
tidal zone where they can influence the nearshore sediment transport. Some
landowners may have constructed these structures during a rare or unusual period
of erosion. When more normal conditions return, these structures are significantly
inland of the foreshore. Therefore, another factor that influences the impact of a
seawall or revetment is the frequency that these structures are in or directly near
the tidal zone where they can influence nearshore processes.

As sea-level rises, the waves reach further inland, encountering more solid
structures. Those structures already within the reach of waves experience increased
wave energy, further eroding any remaining sand. With continued sea-level rise in
Hawaii all coastal structures will eventually increase the frequency that they are in
the tidal zone. This will increase the frequency of erosional events, increase the
severity and magnitude of erosion, and increase the rate and magnitude of beach
loss.

Around Oahu and Kauai sea level is rising a little over one-half inch per
decade. Because of the volcanic growth of the Big Island, both it and Maui are
sinking. This effectively more than doubles the rate of sea-level rise on those
islands (total rate of about sea-level rise is about I in/decade. for Maui, 1.5
in/decade for Hawaii). These are historical rates based on tide gauge data over the
later part of this century. If we accept widespread predictions for accelerated rates
of sea-level rise in the next century, then we can expect rates of sea-level rise on
Kauai and Oahu to increase to nearly two and a half in/decade, and on Maui and
Hawaii to average three in/decade. Depending on if and when the accelerated rise
begins, thirty to forty years from now the sea may be five to ten inches higher.
While this may not seem like tragic news now, in fact it points to serious problems
for shorelines and development in the future.

Most of our buildings around the islands stand on relatively flat and gentle
coastal plains and terraces. Because of the low slope of the land surface, we can
expect a landward movement of the waterline of between thirty to fifty feet or
more. This- rise will have two pronounced effects. First, as waves reach farther

inland, more coastal property will be threatened and more of the shoreline may be
armored. Property owners will seek to protect their land from erosion. Low-lying
developed areas will be the first sites where increased stabilization will occur.
Second, for existing seawalls and revetments which are presently inland from the
tidal zone, the landward migration of the waterline will increase the frequency these
structures affect the foreshore. A hypothetical increase in the frequency that
structures interact with waves in the tidal zone, say for example from 20% to 50%
of one tidal period, may be sufficient to initiate beach loss. Add to these two
factors the storms and high waves that hit the beaches on a regular basis, and it can
be concluded that future beach loss in the State may accelerate to a critical level
without a fundamental change in shoreline management.

Since beaches are very sensitive to wave dynamics and the position of the
water line, their loss along stabilized shorelines may be one early barometer of
elevated sea level around the islands. Recent studies for the U. S. Army Corps of
Engineers (Tait and Griggs, 1991) show that shorelines stabilized with vertical
structures experience beach loss under long term sea-level rise. As discussed in
this Chapter, accelerated beach loss is occurring in the Hawaiian Islands in
association with long term sea-level rise. It is exactly these kinds of changes that
are to be anticipated if sea-level rise continues or accelerates. In fact, the -MOESE
projections for the 2018 shoreline on Maui reflect twice the rate of recession of
those on Oahu and Kauai. Since current sea-level rise on Maui exceeds twice the
rate of rise on Oahu and Kauai, the higher shoreline recession rate may be a
consequence of this difference in the rate of sea-level rise.

A collision is taking place. As development continues along the shoreline,
the sea is rising, moving closer to development. In the process the beaches are
being sacrificed. This trend is expected to increase in the coming decades because
of accelerated sea-level rise aiid the continued use and need for shoreline
stabilization structures.

E. Mitigating the Problem - Modification of Coastal Land Use

Intelligent stewardship of coastal resources requires balancing human
expectations with coastal realities. This partnership must consider the natural
processes, in light of human needs. Beach loss by stabilization is an example of
where human expectations have not been balanced with reality. In trying to protect
valuable -coastal land from erosion to meet the expectation of living on the coast,

the reality that building seawalls and revetments results in beach loss has been
ignored. The need to protect coastal property with seawalls and revetments can be
avoided by the recognition and consideration of coastal processes in land use
planning.

Land use strategy in this study is driven by the principle that the most
beneficial approach in the long run is to plan for the impacts of coastal flooding
and erosion before development in order to minimize damage to natural resources
and property and reduce the necessity of public expenditures to protect the
development. From the examples, summaries and discussion in this chapter, the
following should be considered in the planning process:

1) The loss of beach resources may occur for chronically eroding shorelines
(Iroquois Point), unstable shorelines (Lanikai), shorelines that were previously
thought to be accreting (Punaluu), and shorelines that are relatively stable (west end
of Kahala). The common denominator for the above sites is not persistent erosion
but hardening of the backshore to prevent any movement of the shoreline.

Many of the problems documented in this study could have been avoided with an
adequate shoreline setback before development. Many of the lots at Kahala and
Lanikai are large enough to accommodate a setback that would have been more
conducive to beach preservation. Kailua Beach on the windward coast of Oahu is
a good example of the benefits to the public and the coastal homeowner when the
beach is given room to migrate (Fig. 22).

2) In general, the beach in its natural condition will be preserved even if it is
chronically -eroding adjacent fastlands. There are numerous examples that support
this premise including Iroquois Point (see Fig. 2, 1967 photo); and the beach sector
at Kahului, Maui, to the east of the Kahului Wastewater Reclamation Facility
(MOESE, 1991). Wherever and whenever possible, development should be planned
so that shorelines can migrate naturally. This approach could lead to the loss of
fastlands. Erosion mitigation strategies such as sand replenishment could preserve
the beach and eliminate the loss of these fastlands.

3) Degradation of the beach resource is a slow process. The environmental effects
of poorly placed development may not be noticeable for many years. Because of
the latent impacts on the shoreline, there is often a lack of accountability as to land
use decisions along the coast. Planning of shoreline development needs to be

ta'@L
51@1

1 7

IiA i

iw :z

Figure 22. Lanikal and Kallua Beach, Oahu. The north ends of Lanikal Beach and Kailua Beach
are both unstable. TOP: At Lanikal Beach, development of houses close to the beach resulted
In hardening of the shoreline to protect property during a period of erosion. The beach has been
lost. BOTTOM: At Kallua Beach, the houses are generally set far from the vegetation line.
Natural fluctuations of the beach can occur without threatening private property. At Kailua,
human s are living in harmony with the environment.

43*

conducted on a long term horizon. Since proposed programs under the Federal
Flood Insurance program utilize a 30 year time horizon, it is recommended that
coastal development in Hawaii should be planned over a similar period to take
advantage of potential benefits under this and other Federal programs.

In Chapter VIII of this report, land-use strategies are formulated which
consider the above factors, as well as legal considerations and specific landowner's

concerns.

F. Cooperation, Coordination and Sacrifice

As presented in this chapter, the problems associated with sea-level rise and
loss of beaches are critical. Meaningful changes in the management of the
shoreline may be required. If it is possible, reversing the historical trend will
require cooperation and coordination among individual landowners, the public, the
counties and the State. The strategies developed in this report emphasize
cooperation among diverse groups and working relationships over adversarial ones.

To achieve the desired result, it will also require some sacrifice from all
parties involved. In this study, various programs that address the shoreline problem
are structured so that the burdens are shared fairly. In the long term, all parties,
including the coastal landowner, may benefit.

There is still time for a well-planned response, provided the State acts with
commitment and purpose. Innovative shoreline management policies are presented
in this report. Early construction set-back guidelines are proposed, and there are
alternatives to stabilization that are discussed in Chapters V, VI and VIII.
Nevertheless, more may be needed if the beaches are to be preserved. The
following should be considered: detailed feasibility studies of beach nourishment
with offshore or onshore sand resources; a State-wide beach monitoring program
to assemble a scientific data base supporting informed coastal zone management;
development of a voluntary economic incentives plan to convert private coastal
holdings to public conservation land; review of existing stabilization structures and
the return of beaches to a natural state where practical.

111. PRIVATE & PUBLIC PROPERTY RIGHTS IN THE SHORELINE

The definition of private landowner and public rights in the shoreline is
essential in the development of any coastal land use policy, beach management
plan, beach management district, or funding scheme in which burdens are shared
among diverse parties. This topic alone could be the subject of lengthy treatise.

While considerable attention is often placed on private property rights along
the coast, little consideration or understanding is placed on any public rights that
may exist. All parties involved, including the State, the counties, the public and
the landowners should realize that there are two sets of property rights along the
coast, both private and public. Each of these rights needs to be respected and
protected. That means the coastal landowner must respect the legitimate right of
the State and the public in taking action to prevent the fin-ther loss of beaches. In
return, the State and public need to honor the concerns and legitimate property
rights of the coastal landowner.

Striking the proper balance between private and public interest is difficult
because the coastal zone is a unique environment. What makes management of the
shoreline so complex is that the boundary separating the two rights is not fixed but
always moving, on a daily, seasonal and long-term basis. Furthermore, because of
the sand exchange between offshore sand bars, the dry sand beach and backshore
area, what one party does on a portion of the beach ecosystem may affect the
property rights in other segments of the system.

A. Public Property Interest

Under the public trust doctrine, the State holds certain lands in trust for the
benefit of the public. The public trust doctrine is applicable in Hawaii. In King
v. Oahu Railwgy & Land Co., I I Haw. 717, 1899, the Hawaii Supreme Court held
that lands under the navigable waters in and around the territory of the Hawaiian
-Government are impressed with a trust for the public useIs of commerce, navigation
-and fishing. The Supreme Court in Oahu Ry. did not define the upper boundary
of the domain of the public trust. Part of the reluctance is due to the confusion
in the definition of navigable waters. This definition originally applied to those
waters subject to the ebb and flow of the tide. However, many inland lakes aud
streams, which are subject to the public trust doctrine, are navigable but not subject
to the influence of the tides. Conversely, many coastal ecosystems are subject to

tidal influence but not navigable.

The United States Supreme Court in Phillips Petroleum Co. v. Mississip i,
108 S.Ct. 791, 1988, clarified this issue when they reaffirmed prior precedents and
held that all lands subject to the ebb and flow of the tide, whether navigable in fact
or not, are subject to the State's public trust interest. Thus in Hawaii, the upper
boundary of the public trust interest extends at least to the mean. high water line.
The mean high water line would be the intersection of the horizontal mean high
water level with the coastline.

There are two lines of reasoning that indicate the public trust doctrine
extends farther inland to include the dry sand beach. First, the law of general
application in Hawaii is that the boundary separating public and private interests
along the shore is the upper reaches of the wash of the waves, excluding storm and
tidal waves, as evidenced by the vegetation and debris line, (see e.g., Application
of Ashford, 50 Haw. 314, 440 P.2d 761 1968; County of Hawaii v. Sotomura, 55
Haw. 176, 517 P.2d 57, 1973; Application of Sanborn, 57 Haw. 585, 562 P.2d 771,
1977. Given the above cases, beaches in Hawaii are generally held to belong to
the public. A 1978 addition to the Hawaii Constitution (Article X1 - Section 1)
states that "All public natural resources are held in trust by the State for the benefit
of the people." Second, in the Sanborn case, the Hawaii Supreme Court approved
their previous analysis in Sotomura, when it recognized that land below the high
water mark is held in public trust by the State. The Sanborn court held that the
high water mark is the upper reaches of the wash of the waves as represented by
the vegetation and debris lines.

In sum, the upper boundary of the public trust doctrine extends at least to the
mean high water line (the intersection of mean high water with the coast) and
probably to the upper reaches of the wash of waves (usually evidenced by the
vegetation line or debris line). Wherever the inland boundary is located, the
disappearance of beaches as shown in Figs. 1-5 of this report may be a violation
of the public trust since these changes represent serious harm to both the dry sand
beach and tidelands (land between the mean high water line and lower low water).

That the State holds beach resources (tidelands or the dry sand beach) in trust
for the public has important implications that are discussed below:

1) Because the beneficiaries of the trust are the public, the courts may allow

individual citizens to assert the rights of the public in a lawsuit. In Akau v.
Olohana Co1p., 652 P.2d 1130, 1982, the Hawaii Supreme Court held that a
member of the public has standing to sue if he can show he suffered an injury in
fact (the previous more difficult standard was that the citizen suffered an injury
different in kind from the general public). The Akau Court recognized the trend
of allowing citizen suits for harm to public trust property. The Court noted that the
State, in its brief for the case, said it welcomed private suits because the State
lacked the resources to pursue vigorously all such claims.

2) It is important to distinguish between the State's police power to regulate land
use for the health, safety and welfare of the public and the more demanding and
rigorous duty that the State has as trustee of natural resources. Under the police
power, the State may decide that a rarely used beach can be sacrificed to protect
private property with seawalls along an eroding shoreline. Under the public trust
doctrine, the State is a trustee of a public resource and should defend, preserve,
protect, maintain and perpetuate that resource. The basic tenet of the public trust
doctrine was espoused by the Hawaii Supreme Court in the Oahu Railway case.
The Hawaii Court adopted the reasoning in Illinois Central R.R. v. Illinois, 146
U.S. 3 87, 13 S. Ct. I 10, where the United States Supreme Court held that title to
land below the high water mark was: ". . a title held in trust for the people of
the state, that they may enjoy the navigation of the waters, carry on commerce over
them, and have liberty of fishing therein freed from the obstruction or interference
of private parties. . . " Without going into an exhaustive legal analysis, a
generalization which can be made of the public trust doctrine is that neither the
United States Supreme Court nor any state courts have disavowed the prohibition
against "substantial impairment of public rights of navigation, commerce and
fishing as announced in Illinois Central or Shively v. Bowlby" (Wilkinson, 1989).

The Hawaii Supreme Court has yet to fully elaborate on the range of
activities covered by the public trust doctrine. In State by Kobgyashi v. Zimring,
58 Haw. 106, 566 P.2d 725, 1977, the Hawaii Supreme Court suggested that
recreational activities, as well as navigation, commerce and fishing may be covered
by the public trust doctrine. In Tern v. Kerr, 16 Haw. 363, 1905, the Hawaii
Supreme Court employed public trust principles to enjoin the construction of a
seawall on *the tidelands of Waikiki. The Court stated that walls and buildings
extending seaward beyond the high water mark "interfere with the rights of
fisheries and of navigation by fishermen . . . . and of the right of passing
between high and low water mark common to the public. And that the structures

do and will interfere with navigation of canoes within the limits and below high
water mark and if allowed to remain or if allowed to be completed as
planned, will work irreparable damage to the rights and interests of the Territory
of Hawaii." Lower courts in Hawaii have also made the connection between the
loss of beach access and the duties of the State under the public trust (Lam, 1991).
In Barba v. Okuna, Civil No. 4590, Findings of Fact and Conclusions of Law;
Order (October 14, 1980), Hawaii's Third Circuit Court stated "Any alienation or
abandonment of an established public right-of-way by the Defendant State of
Hawaii which leaves the public without reasonable access to Kawa Bay and the
adjacent shoreline would constitute a breach of public trust. . . The Barba case
involved the blockage of vertical access to the shoreline (e.g. trails, roads and paths
to the coastline). With regard to the loss of beaches as documented in this report,
it is horizontal access along the coastline which is blocked. The Kerr and Barba
cases indicate that the State should protect both vertical and horizontal access to
the shoreline as part of their public trust duties.

3) Since it is the State that owns the beaches and is the trustee of the coastal
resource, it is the State that should take the lead in managing these resources.
While the counties through enabling legislation can regulate and manage shoreline
development, history indicates that the greater weight has been given to county
concerns as opposed to those of the State's. As a result, State property was lost
(the beaches were balanced away).

In this report, the principles and concepts discussed in paragraphs 2 and 3
serve to guide the formulation of strategies and define a direction of coastal
management for the State. In developing strategies, it is the State that should take
the lead and assume its role as trustee of coastal resources. The philosophy of the
State should be that preservation and restoration of the coastal environment should
be a primary principle upon which alteration of shoreline resources should be
judged. This philosophy is reflected in the strategies and options developed within
this study.

B. Private Property Interest

All landowners, whether along the coast or not, have a bundle of property
rights. There are certain restrictions the government can and cannot place on these
property rights through regulation. While the government can regulate land use to
a certain extent, if the regulation goes "too far" it will be recognized as a taking of

property without just compensation (Pennsylvania Coal v. Mahon, 260 U.S. 393,
43 S. Ct. 1581) 67 L.Ed. 322 (1922). For example, if the government were to
physically occupy the land or pass a regulation that allowed others to occupy the
land, the Courts would invariably find a taking, which would require the payment
of just compensation to the landowner (See Loretto v. Telorompter Manhattan
CATV Corp. 458 U.S. 419, 102 S.Ct. 3164, 73 L.Ed.2d 868 (1982).

The United States Supreme Court has stated that there is no set formula for
what constitutes a regulatory taking. A variety of factors are considered by the
Court on a case-by-case basis. Some key factors concerning coastal regulation and
shoreline setbacks are: 1) Economic Impact - e.g., does the regulation deny "all
economically viable use" of the land; 2) Government Objective - is the
government preventing a serious harm and nuisance or is the government securing
a benefit for the public; 3) Relationship between the Regulation and the State
Interest - does the regulation "substantially advances a legitimate state interest";
and 4) Propegy Expectations - what are the "investment backed expectations" of
the landowner.

Recently, the United States Supreme Court ruled on a pivotal case that
affects government regulation of property (see, e.g., Callies, 1992). In Lucas v.
South Carolina Coastal Council, 304 S. C. 376, 404 S. E.2d 895 (1991); cert.
granted (U.S.S.C., Nov. 18, 1991) (No. 91-453), the landowner Lucas purchased
two lots in 1986 for a price of $975,000. Lucas planned to build two single fwnily
dwellings, one for his fwnily and the other to place on the market. In 1988, South
Carolina passed the Beachfront Management Act, which imposed strict shoreline
setbacks to prevent erosion problems. As applied to the Lucas property, the
setback prohibited construction of habitable units seaward of setback that was based
on a 40-year erosion rate plus 20 feet as an additional buffdr. There were no
exceptionsl S. C. Code S 48-39-290(A) (Supp. 1988).' Even though Lucas
conceded the validity and purpose of the South Carolina Act, he claimed that the

The Beachfront Management Act was later amended to allow special
permits or variances to build closer to the beach under certain conditions, S. C.
Code s 48-39-290 (1990). However, the United States Supreme Court ruled on the
viability of the Beachfront Management Act in its preamended version (1992 WL
142517). The Court held that Lucas alleged irijury-m-fact with respect to the
preamended Act, and it would not accord with sound practice that he pursue a late
created procedure before his case could be heard.

setback was a taking since "all economically viable use" of the land was lost. The
South Carolina Coastal Council maintained that regardless of the economic impact
to the landowner, the State can regulate land to prevent a serious public hann. or
a nuisance.

The trial court held that Lucas's properties had been "taken" by the Act and
ordered the respondent, South Carolina Coastal Council, to pay "just compensation"
in the amount of $1,232,397.50. The South Carolina Supreme Court reversed the
trial court and held that the Beachfront Management Act did not amount to a taking
since it prevented a serious public harm, 304 S. C. 376, 383; 404 S. E.2d 895, 899
(1991). The South Carolina Supreme Court's holding in Lucas is in line with other
cases dealing with shoreline setbacks and the takings issue (see, e.g., McNulty v.
Town of Indialantic, 727 F. Supp. 604, M.D. Fla. 1989; see generally, Hwang
1991).

The United States Supreme Court reversed the South Carolina decision (1992
Westlaw 142517). The U. S. Court held that regulations that deny a property
owner of all "economically viable use" of the land constitute one of the discrete
categories of regulatory deprivations that require compensation, regardless of the
public interest advanced in support of the restraint. Furthermore, the Court stated
that the distinction between regulations that prevent harm versus those that confer
a public benefit is difficult, if not possible to discern on an objective basis.
Therefore regulations that prevent a harin cannot form the basis for departing from
the Court's categorical rule that total regulatory takings must be compensated for.

Nevertheless, the Court left open the door to State' regulation to prevent
serious public harm, even if all use is deprived. The Court stated that no
compensation is owed if the State regulation simply makes explicit what already
inheres in the property itself, "in the restrictions that background principles of the
State's law of property and nuisance already place on land ownership." Thus, the
U. S. Court remanded the case to South Carolina to address this state-law question.
In order for the South Carolina Coastal Council to win their case, they must
identify background principles of nuisance and property law that prohibit the uses
that Lucas intends on his property.

The majority gives examples of the types of regulations that may be
constitutionally valid. For example, the owner of a nuclear generating plant may
be ordered to remove all improvements from the land upon discovery that the plant

sits astride an earthquake fault. The example given by the Court that is more
applicable to coastal regulation is that of flood regulation. The Court states that
the owner of a lake bed, "would not be entitled to compensation when he is denied
the requisite permit to engage in a landfilling operation that would have the effect
of flooding others' land. . . Such regulatory action may well have the effect of
eliminating the land's only economically productive use, but it does not proscribe
a productive use that was previously permissible under relevant property and
nuisance principles. The use. of these properties for what are now expressly
prohibited purposes was always unlawful." 1992 Westlaw 142517, p. 25.

The majority does not discuss the similarity between regulating an erosion
zone as opposed to a flood area. It is relatively simple to document examples
where attempts to control erosion on one land transfer the erosion problem to
anothers' land. In fact, Chapter 2 of this report contains numerous examples where
landowner activity has the effect of exacerbating erosion on adjacent private and
public land.

If a State was to pass strict setback regulations, an attempt should be made
to define background principles of nuisance and property law. The public trust
doctrine, discussed in part A, is one common law theory that may restrict certain
activities near public trust land. For example, if the development on a lot adjacent
to an erosion zone would lead to the loss of public trust land, then the Lucas Court
indicates a regulation that makes explicit a pre-existing restriction may be valid.
To pass a strict restriction, documentation similar to that in Chapter 2 would be
needed to define the impact on public trust land. Documentation on the individual
lots or the locality in question would also be required.

It should be reemphasized that the Lucas case deals with the issue of
regulating small lots to the extent that all use of the property is gone. For small
lots that have been subdivided but not yet developed, land use options are limited
since a shoreline setback that protects the beach and preserves buildable area may
be mutually exclusive. The zoning strategies in this report should not be affected
since thpy are designed to affect large tracts of land that have not been subdivided
or zoned for urban use. Through innovative strategies, it is possible to develop a
setback that preserves the beach and maintains or enhances economically viable use
of the land (Chapter VIII).

IV. MANAGEMENT OBJECTIVES & STRATEGY

A. Objectives

In Chapter II, the loss of Hawaii's beaches was documented as resulting from
the combination of long-term sea-level rise and extensive shoreline hardening.
This report has three objectives that address this problem. The objectives pertain
to the following levels of use along the coast:

1) Undeveloped Land - One purpose of this study is to develop a strategy for
undeveloped land to ensure that beach resources are not threatened. Generally, it
is easier and more cost efficient to preserve a beach through regulatory controls
than to recover a beach through engineering solutions. For land that is
undeveloped, regulatory controls will be the major management tool. Factors that
will be considered in formulating land controls include beach preservation,
landowners property rights, and other legal and economic factors.

2) Developed Land - (No Seawalls or Revetments) For developed beaches that
have not been hardened, the goal is to devise options that preserve the beach yet
provide protection to the landowner. This means finding alternatives to seawalls
and revetments. New options for landowners will have to overcome the difficulties
of cost and regulatory compliance for activities makai of the vegetation line. It is
through the Beach Management District that these problems can best be addressed.
In those instances where technical, legal or financial difficulties leave no other
alternative, buried erosion control structures on the landowner's property may be
the preferred method of protection (see e.g., DHM, inc., September, 1990).
Nevertheless, because of the continued rise in sea-level, this option may be
temporary.

3) Developed Land - (Seawalls and Revetments - Beach Lost) For shorelines that
are developed and the beach is lost, an attempt should be made to restore lost
resources. Restoration can be provided either by sand replenishment through the
BMD option or through a voluntary program of retreat from the shoreline based on
the provision of economic incentives.

The ultimate goal of this study is to formulate a menu of options that are
technically, economically and legally feasible for the State and landowner. All the
options developed in this report will be preferable, from a perspective of preserving

the beack over a seawall or revetment. It is hoped that at least one or more of the
alternatives will be applicable for every stretch of beach along the State.

B. Strategies

Five basic strategies are employed in this report to develop options that
preserve the shoreline. They are as follows:

1. Develo the Beach Management District. Regarding an erosion control
response, there are alternatives to seawalls and revetments that may be less harmful
to the beach yet considerably more difficult to implement because of cost or
permitting. Through BMDs, it is possible to raise the viability of other technically
feasible options so that they become realistic alternatives to landowners. Structural
and nonstructural options such as offshore breakwaters or sand replenishment will
be investigated within the BMD concept.

It is realized that the formation of BMI)s may not be technically,
economically or legally feasible for every stretch of beach in the State. Therefore
other strategies are required to address the pervasive problem of sea-level rise,
shoreline hardening and beach loss.

2. Implement Economic Mechanisms in Beach Management. In the field of
Federal environmental regulation, Congress and the Environmental Protection
Agency are increasingly exploring the utilization of economic incentives for
activities which preserve the environment and economic disincentives for activities
that degrade the environment. Economic disincentives can come in the form of
taxes, fees, or assessments. Economic incentives may include tax credits, tax
deductions, subsidies, and tradable privileges to conduct certain activities near the
shoreline. The advantage of a program of economic mechanisms to achieve
environmental goals include the following:'

(a) Reduced Government Expenditures - Economic mechanisms may reduce
government expenditures for environmental programs. This is an important
consideration during a time of tight budget constraints.

(b) Revenue - Economic disincentives are a source of revenue for other
environmental programs.

(c) FlexibiliV - Fees or taxes on unavoidable activities that degrade the
environment can contribute revenues to other programs that preserve or restore the
environment in another area.

(d) Business Planning - Economic disincentives allow businessmen to plan their
activities with the environment. Since a price is put on activities that degrade the
environment, businesses can formulate other alternatives to achieve a lower cost
while preserving the environment.

For this study a limited program of economic measures will be used to
develop beach management strategies. Economic incentives and disincentives could
be used to deal with the significant problem of illegal seawalls and revetments. In
addition, economic incentives could provide for a voluntary program to relocate
buildings and erosion control structures inland.

3. Achieve Regulatory Efficiency. When landowners build seawalls or
revetments on their land, they may need only one variance from the appropriate
county agency. However, if they wish to protect their property with erosion-control
measures that are less harmful to the beach, such as beach replenishment, a
breakwater, or a terminal groin, up to six permits may be required. Depending on
the type of activity to be conducted, the following may be required:

Counjy Permit - If the landowner's activities extend mauka of the shoreline,
for example, a groin which goes from the backshore into the water, a county
variance would be required pursuant to appropriate setback regulation.

Dgpartment of Land and Natural Resources - Land makai of the shoreline is
conservation land. Any use within the conservation areas Would require a
Conservation District Use Permit. In addition, an environmental assessment would
be required according to Chapter 343, Hawaii Revised Statutes. If adverse impacts
are found, an Environmental Impact Statement may be required.

Dgpartinent of Transportation - Under Chapter 266-1 of the Hawaii Revised
Statutes, all ocean waters and navigable streams are under the care and control of
the DOT. For ocean dredging, filling, construction and dumping of materials below
the mean water line a Shorewaters Permit is required. The DOT permit is
processed and issued concurrently with the Conservation District Use permit from
the DLNR. However, DOT has the prerogative to disagree with the Conservation

Permit and may request that the applicants obtain a Shorewaters permit.'

AMy C=s of Engineers - If the activities of-the landownerextend seaward
of the high water line, then a permit from the Army Corps of Engineers may be
required under section 404 of the Clean Water Act. Corps permits are required for
dredging, mooring buoys, the discharge of fill material, and the construction of
erosion-control structures such as groins or breakwaters. That a Corps permit is
required triggers the requirement for the following two permits, as mandated by
Federal law, and administered by State agencies.

Coastal Zone Manaizement ProgLam - Under the Federal consistency
provisions of the Coastal Zone Management Act of 1972, all Federally licensed or
permitted activities affecting the coastal zone must be conducted in a manner
consistent with the State's approved management program. For Hawaii, the
activities must be in accordance with the objectives and policies of Chapter 205A-2
of the Hawaii Revised Statutes.

Dgpartment of Health - According to Section 401 of the Clean Water Act,
any applicant for a Federal license or permit to conduct any activity that may result
in a discharge into the navigable waters shall provide the licensing or permitting
agency a certification that the discharge will comply with applicable provisions
relating to water quality standards. Monitoring of water quality is required before,
during and after the proposed activity.

The regulatory process itself can deter a landowner from selecting an erosion
control option that is less harmful to- the environment. Although efforts have been
made to streamline the process, further measures may be necessary. Achieving
regulatory efficiency is especially important since programs to preserve or restore
beaches may take additional regulatory controls. Such regulations will be greeted
with skepticism unless the regulatory process can be made less burdensome, even
with the new controls. In this study, recommendations for additional efficiency
measures and coordination are made so that even with new shoreline programs, the
total number of required approvals is reduced.

On July 1, 1992 the boating program functions and all boating facilities
will be transferred from the Harbors Division of DOT to DLNR. Jurisdiction of
this program will be with the DLNR, Division of Boating and Ocean Recreation.

4. Enforce Existing Regulations. Additional protection of the shoreline may
be obtained by enforcing existing coastal regulations. In the 1991 report,
Recommendations for Improving the Coastal Zone Management Program, it was
recognized that violations of the SMA permitting process and shoreline setback
provisions are a major problem. One reason for the violations is the lack of
sufficient enforcement capacity by the counties. In this report, suggestions are
made for improved enforcement of existing regulations.

5.'Offset Burdens with Benefits. There are three major approaches to deal
with coastal erosion, beach loss and sea-level rise. The State may decide that the
present, system of beach management is working and no further action is required.
As discussed in Chapter II, this approach would lead to continued or accelerated
degradation of the coastal environment and increased risks to landowners.

A second strategy is to adopt a strict policy of retreat from the coastline
similar to that enacted by South Carolina. In South Carolina's Beachfront
Management Act, there are strict prohibitions on erosion control structures and new
development seaward of a forty year erosion setback. The advantage of the South
Carolina Act is that it protects coastal resources and is relatively easy to administer.
The disadvantage is that the Act may intrude on private property rights. The. South
Carolina law does test the limit on the extent government can regulate private
coastal property for the good of the public (see e.g., Lucas v. South Carolina
Coastal Council, 404 S.E.2d 895, (S.C., 1991); cert. granted 112 S.Ct. 436, 116
L.Ed.2d 455, 60 U.S.L.W. 3374 (U.S.S.C., Nov. 18,1991) (No. 91-453); and Beard
v. South Carolina Coastal Council, 403 S_.E.2d 620 (S.C.1991); cert. denied, 112
S.Ct. 185, 116 L.Ed.2d 146, 60 U.S.L.W. 3262 (U.S.S.C., Oct. 7, 1991)(No., 91-
137). In Hawaii, a strict policy of retreat from the coastline may encounter strong
opposition that could disable any proposals to protect the shoreline.

A third approach, and the one that is suggested in this report, is to formulate
an erosion management program in which burdens placed on affected parties are
compensated with other benefits. The drawback of this altemative is that the
shoreline management program becomes more complex since it requires the
development of a benefit for every burden imposed. This alternative also requires
strong cooperation between the State and county governments. The advantage of
offsetting burdens with benefits is that it can reduce political opposition from
landowners and developers. Therefore, meaningful programs can be implemented
to preserve-the State's shoreline.

V. BEACH MANAGEMENT DISTRICTS

The Beach Management District would be used to pay for the design,
analyses and capitalization of erosion-control measures. The advantage of forming
a district is that it provides economies of scale. For many erosion control projects,
the cost to a single homeowner for a comprehensive coastal study may be more
than the cost to build a seawall (Edward K. Noda & Assoc., 1989). However, if
many landowners were to split the cost of the study, they would benefit since
alternatives other than seawalls may be developed in the coastal analysis. Through
the cooperation of landowners, the counties and the State, it may be possible to
develop and finance alternatives such as offshore structures, sand replenishment,
or a field of leaky groins.

Many coastal states have established Beach Management Districts (BMDs)
to deal with coastal erosion. The success of these programs has varied on the type
of district established and the level of cooperation from the State and local
governments.

A. The District Structure

There are numerous variations of the district concept that have been used for
capital improvement projects. They include the improvement district, the overlay
district, and the special taxing district. Coastal States that have established BMI)s
have used one or a combination of the three forms. The various forms of the
district are discussed in order of increasing complexity.

1. The Overlqy District.' The idea behind an overlay district is that certain
areas may be so unique in terms of land use, historical significance, scenic beauty
or economic value that another layer of regulation or additional restrictions may
be needed for the building and design of structures. In the Hawaii State Land Use
Enabling Act, (HRS S 46-4) the counties are given the power to determine land
areas in which particular uses may be subjected to special restrictions. Examples
of districts on Oahu with another layer of regulation include Diamond Head and
Punchbowl craters, the Hawaii State Capital, Chinatown, Thomas Square/Honolulu
Academy of Arts, Waikiki and Haleiwa (Dept. of Land Utilization, Land Use
Ordinance S 7.20-7.90). In addition there are overlay regulations governing

Also known as a special district in the Oahu Land Use Ordinance.

specific Federally established Flood Hazard Districts (LUO S 7.10).

According to the Kauai County Zoning Ordinance, special overlay Shore
District Zones may be -established (Ord. No. 164, August 17, 1972). For the Shore
District, the Planning Commission of Kauai was supposed to develop a Shoreline
Special Treatment Zone Plan which delineated the boundaries of the Shore District.
New developments within the zone are to address certain environmental issues , such
as water quality or public use of the ocean. In addition, the Shore District has
some restrictions on seawalls, bulkheads and other erosion control structures.
These overlay Shore Districts have yet to be implemented by Kauai (DHM, inc.,
1990).

. Previous studies in Hawaii have proposed the establishment of overlay
districts (see, e.g., Edward K. Noda & Assoc., 1989; DHM, inc., 1990; Sea
Engineering, 1991). At the county level, overlay districts may be useful for
shoreline sectors with unusual problems or unique characteristics. For example, the
beach at Waikiki is unique fi7om other sandy shorelines in terms of visitor usage,
types of activities and economic importance. For Waikiki, a special layer of
regulation and unique standards to protect the beach may be warranted.

Overlay districts may be useful if State legislation is ineffective to prevent
erosion problems at a particular locality. In this case the counties can establish an
overlay district with more stringent zoning controls for the area. Overlay districts
may -also be needed if the counties were to develop a special program to grant
height and density variances for those landowners who were subject to an increased
shoreline setback (see proposal - Chapter VIII).

While the overlay district may be useful for certain areas, its application to
most of Hawaii's beaches may be cumbersome. In considering the utility of an
overlay district as a method of regulatory control, one consideration would be how
unique the problems are at a particular locality. If the problems associated with
coastal erosion and beach loss are limited to a few sites, then the formation of
overlay districts to counter the problem may be appropriate. However, if the
coastal problems are extensive, then it may be more efficient to apply meaningful
regulatory guidelines and criteria at the State or county level.

Previous studies indicate that the problems associated with erosion and beach
loss are extensive. According to the MOESE report, sixty-three sites on Maul will

retreat an average of thirty-six feet by the year 2018. The examples at Kahala,
Punaluu and Lanikai on Oahu (Figs. 3-6) indicate that beach loss is not confined
to chronically eroding shorelines but also to stable beaches and areas that were
formerly accreting. In addition, the, difficulties associated with accelerated sea-level
rise are expected to increase the number of trouble areas along the, coast. Another
important consideration is that the State is trustee of the beach resource. As a
trustee, effort should be made to protect all beaches, not just those with unusual
characteristics. Therefore, the number of beaches to protect by special overlay
regulation could be considerable.

The establishment of numerous overlay districts along the Hawaii coastline
may be burdensome. More efficient in a statewide beach management program
may be effective controls at the State or county level. This is not to discount the
important value of the overlay district. If the State were unable to develop
meaningful guidelines for beach management, it may be up to the counties to take
the initiative and develop individual overlay districts for various areas.

The overlay district and the improvement district are not mutually exclusive.
Each is suitable under different conditions. In many cases, both may need to be
utilized. Since much of the legal structure is already in place to develop the
overlay district, more time was spent in this report to develop the improvement
district. In Chapter X, an attempt is made to apply both the improvement and
overlay district concept to two different beach areas.

2. The Improvement District. For an improvement district, a special
assessment is charged upon lands deriving some benefit from a nearby capital
project to defray some of the cost of the improvement.- The charge of assessments
must be limited to situations where there is some benefit to the property assessed.
The charge cannot be for more than the benefit received nor for more than the cost
of the improvement (Hagman & Juergensmeyer, 1986).

Traditionally, assessments were used to pay for improvements to streets,
sidewalks, lights and sewers. In the Hawaii State Land Use Enabling Act, (HRS
46-1.5), the counties are given the power to provide by ordinance for the funding
of improvements or maintenance within a district by the use of assessments. In
Oahu's special assessment ordinance, assessments may cover activities to establish
highways, extend or widen streets, improve sanitary and drainage systems, and
acquire property for playgrounds and public beach parks (City and County of

Honolulu, Revised Ordinances of Honolulu, Chapter 24).

Improvement districts may also be used as a tool to finance offshore
breakwaters) sand replenishment, or other non-traditional erosion control projects
(Edward K. Noda & Assoc., 1989). Numerous coastal states have used the
improvement district concept to finance erosion mitigation projects. In
Connecticut, special assessments for erosion mitigation are allowed for the
construction of groins, jetties, seawalls, revetments and other structures and
facilities useful in preventing damage from floods or erosion (Conn. Gen. Stat.
Ann., Title 25-Water Resources, S 25-71). In Rhode Island, assessments are made
on property which benefit from protective works along the shore (R.I. Gen. Laws
S 46-3-12). For North Carolina, improvement districts at the county level may be
made for water systems, street widening and for beach erosion control projects
(N.C. Stat S 153A-185). In Maryland, the State assesses shoreline properties that
benefit from the design and installation of bulkheads, groins, and other devices.
Benefited properties include land immediately abutting the waters of Maryland that
receive protection from an erosion control project (Md. Nat. Res. Code Ann. S 8-
1001).

The improvement district is a valuable tool that can be of use for selected
portions of the coast. It is recommended that improvement districts be formed for
erosion mitigation projects that benefit the State and private landowner so that the
costs can be shared equitably. The improvement districts can be modeled after the
regulations from other coastal states and Oahu's Improvement District Ordinance.

3. Taxing Districts. Taxing districts perform many'of the functions of an
improvement district; however, the revenues that are collected are not limited to
a single purpose or improvement. Taxing districts are organized into small
governmental entities, with a structural forni, the right to obtain and dispose of
property, and the power to issue bonds. These districts are usually run by elected
officials and are subject to a high degree of accountability. They have been used
to create roads, bridges, police and fire protection services and recreational facilities
(Hagman & Juergensmeyer 1986).

In Hawaii, legislation has been proposed to give the counties the authority
to establish taxing districts. In 1990, Senate Bill #3293 proposed the establishment
of Community Facilities Districts in which taxes on property did not have to be
apportioned on the basis of benefit to the landowner. This bill never passed out

of conference committee.

In Florida, beach erosion and mitigation projects may be initiated at the State
or county level. At the county level, Beach and Shore Preservation Districts are
established with many of the characteristics of an overlay and taxing district.
Beach and Shore Preservation Districts at the county level are run by a board of
county commissioners who are elected officials (Fla. Stat. Ann. S 161.25). The
board has the authority to install erosion control structures, make contracts,
establish regulations, acquire land, exercise the power of eminent domain and levy
taxes within the district.

In New Jersey, beach erosion control districts are formed at the municipal
level (N. J. Stat. Ann. S 40:68-27). The district is run by 3 elected commissioners
@J who comprise the Beach Erosion Control Commission. The district may prepare
plans and specifications for the construction of jetties, bulkheads or other facilities
designed to prevent erosion. In addition, the district may. issue bonds and raise
taxes within the district to pay for the bonds (N. J. Stat. Ann. S 40:68-42).

The establishment of a taxing district such as in Florida or New Jersey is a
W-1 complex procedure. For Hawaii, a Beach Management District using. a taxing
format is not recommended because the magnitude of the shoreline problem would
require the establishment of numerous entities or local governments around the
islands. This may result in duplication of efforts and inefficiency.

B. District Formation

In Oahu's Improvement District Ordinance, 60% of the landowners and
lessees to be assessed may petition the City Council for a certain improvement
within a proposed district (Revised Ordinances of Honolulu, Chapter 24, Sec. 24-
3.2). The petition must be accompanied by maps, surveys, plans and other
preliminary data which the City Council use to evaluate the petition. Alternatively,
the city council may, by resolution, propose the formation of a district. In either
case, a notice and public hearing are required that allow all affected property
owners an opportunity to express objections or suggest modifications to the
proposed district.

In Maryland, the owner of any property abutting any body of water of the
State may file a written application with the Department of Natural Resources

requesting assistance in the design, construction, and financing of a shore erosion
control project for the property (Md. Nat. Res. Code Ann. S8-1 00 1). The applicant
must state on the application that they are responsible for the maintenance of the
project after its construction.

It is suggested that provisions are created which allow the establishment of
Beach Management Districts, where they are feasible, upon the initiative of the
State, the county, or a group of coastal landowners. It would be the proposed
Division of State Beaches that would evaluate the petition, and decide on the
viability of a potential project for erosion mitigation.

C. Landowner Cooperation

In the establishment of an improvement district, a critical issue is how to get
a group of landowners to consent or cooperate to a major improvement project.
For Oahu, an improvement district requires the consent of at least 60% of the
landowners and lessees to be assessed (Revised Ordinances of Honolulu, Chapter
24, Sec. 24-3.2). While only 60% of the affected parties must consent, 100% of
the affected parties pay an assessment according to the specific benefit received.

Between 1915 and 1987, over 360 street and sewer improvement projects
have been completed on Oahu. The first improvement district was the Manoa
Improvement District No. 1, initiated in 1915. More recent improvement districts
were in Ewa Beach, Waimalu, and Halawa (Dept. of Public Works, 1987). The
Department of Public Works often encounters the situation where most landowners
consent to an improvement district except for a few holdovers who refuse to pay.
One generality that can be made is that there appears to be more willingness for
landowners to participate in the payment of a sewe .r improvement as compared to
road improvements (Alex Ho, pers. comm., Department of Public Works). This
may be because the Department does not allow the non-consenting landowner to
hook up onto the new sewer until payment is made. There may also be the
perception, whether true or not, that the landowner benefits to a greater degree
from a sewer project versus a road improvement. For road improvement projects,
additional effort may be required to get non-consenting landowners to cooperate.
In some cases.a tax lien may be placed on the property.

In the Hawaii Revised Statutes S 206E-6, authority was given to the Hawaii
Community Development Authority (HCDA) to develop a district-wide

improvement program. An improvement project in the HCDA is initiated by a 2/3
approval of the authority (the board), and the governor's consent (Clayton Goo,
pers. comm., HCDA). Although landowner consent may be considered to initiate
the improvement district it is not a requirement in the formal establishment of the
district.

The experiences on Oahu with improvement districts indicate that although
landowner cooperation may be an obstacle to district formation, this need not be
an insurmountable problem. If landowners can recognize a specific benefit from
an improvement project, they may be more willing to cooperate in the financing
of the project. With regard to beach improvement projects, the benefits to the
property owner include the protection of valuable oceanfront property, increased
recreational opportunities and improved esthetics.

Many coastal states that have provisions for Beach Management Districts
have failed to imple ment these ideas. One common obstacle is getting landowners
.to agree on an erosion control strategy and pay schedule. Landowners tend to be
very when a solution to a problem deals with their own property and
pocketbook.

A lack of landowner cooperation has been a key hurdle in establishing BMI)s
on a comprehensive basis in Massachusetts (Steve Blivens, pers. comm., Mass.
Coastal Zone Management Program). For example when, an inlet broke through
the barrier island at Chatham near the Cape Cod national seashore, the local
officials wanted a plan to control erosion that covered the whole stretch of
shoreline. The landowners preferred to control erosion on a parcel by parcel basis.
One reason landowner cooperation in Massachusetts is a problem is that there is
little participation by the State in coordinating a beach district or contributing to its
cost. While the State prefers coordinated action by the landowners, they prefer to
remain uninvolved by leaving the problem to the local government and private
landowners. Although there are legislative provisions for the formation of beach
management districts at the local level, there has been little success in forming such
districts. An important lesson can be learned from the experience in Massachusetts.
Without an active coordinating agena or an economi.c incentive to cooperate,
landowners prefer to take action on their own.

One State that has experienced success in the establishment of BMI)s is
Florida. Beach and Shore Preservation Districts in Florida are covered under the

Beach and Shore Preservation Act. Several districts have been established and
several more are proposed to replenish beaches with offshore sand. Funding for
projects is derived from the Beach Management Trust Fund, where money is
derived from State appropriations *and permitting fees (Fla. Stat. Ann. S 161.0535,
S 161.091). Payment for beach renourishment in Florida is shared, with 75% of
the cost to be paid from the Beach Management Trust Fund and the remainder
from the local government (Fla. Stat. Ann. S 16 1. 10 1). One reason for the success
of the district concept in Florida is that the State and local governments provide
considerable financial support for various replenishment projects. All funding
comes from State appropriations or local governments.

Maryland has also been successful in the formation of beach erosion control
districts. In Maryland, a shoreline sector may be divided into physiographic units,
which are portions of the coast with similar nearshore processes. For a
physiographic unit project to be established, all property owners within the
physiographic unit must consent. A physiographic unit project may not begin
unless every landowner participates in the planning, construction and financing of
the project (Md. Nat. Res. Code Ann. S 8-1003). In Maryland, erosion control
districts have been formed along the Atlantic Ocean and in Chesapeake Bay (Mike
Helta, pers. comm., Maryland Department of Natural Resources). Along
Chesapeake Bay, several projects to construct bulkheads and offshore breakwaters
have been administered by the Department of Natural Resources. The Department
is very active in helping the landowner. The Department provides, through a Shore
Erosion Control Construction Loan Fund, interest free loans for the design and
construction of erosion, control structures. In addition it selects consultants for
district projects, walks the applicant through the permitting process and handles the
administration of the project. That the Maryland Department of Natural Resources
administers beach districts has been a relief to city and county governments. Many
of the local government agencies do not have the expertise or personnel to. run a
project to control beach erosion.

The success of the district program in Florida and Maryland could be
attributed to the financial support offered by the State in paying for the project or
in providing interest free loans. In addition, both states play an active role in
coordinating the beach project. For Hawaii, it is suggested that a Division of
Beaches be established to help coordinate the activities of landowners and to
administer a dedicated State Beach Fund that would provide economic incentive for
landowners to participate in the Beach Management District.

D. Liability
6@1 There may be some concern about the liability to the county or the State if
they participate in a BMD by building, designing, initiating, administering or
permitting an erosion control structure that eventually fails. Many coastal states
have solved this problem by requiring the homeowners, or other parties to sign an
indemnity or hold "harmless clause" that serves to relieve the State or local
government from liability (See, e.g., Md. Nat. Res. Code Ann. S 8-1001; N. J. Stat.
Ann. App. A:9-51.8). In general, the clauses require that the property owners agree
in writing, before a beach management district is established, to indemnify and hold
harmless the city or the State from any injuries or damages arising directly or
indirectly from a proposed improvement. Similar provisions would be required for
any district that was established in Hawaii.

The homeowner should be aware that the ocean and coastal environment is
a dynamic environment. Absolute safety from natural forces is impossible" for
development along the shore. Structural failure is always possible, whether the
structure is a seawall, a revetment, a series of groins or a breakwater.

The establishment of a BMD is a benefit to the landowner since it provides
protection and adds value to the shoreline property. In addition, part of the cost
is absorbed by the city and State. Therefore, it would be a small request to ask the
landowner to indemnify the city or the State before such a project is undertaken.

In addition to liability from coastal landowners, the State should be
concerned about an injury to a member of the public that is directly or indirectly
related to the formation of a BMD, It is for this reason that a proposed Division
of Beaches would need to monitor beach improvement districts to make sure no
dangerous unnatural conditions exist such as a failed erosion control structure. If
dangerous unnatural conditions are present, the State would need to warn the public
until necessary repairs are made to correct the condition (See, e.g., Littleton v. State
of Hawak, 66 Hawaii 55; 656 P.2d 1336, 1982; in some instances the State is
required to warn the public of dangerous unnatural conditions such as large
telephone poles in the water).

E. Procedures

For many shorelines, there may be no structural or non-structural options

within the district setting that are technically, financially or legally feasible.
Therefore, guidelines and criteria would have to be adopted for the review of
petitions to form Beach Management Districts.

For those shorelines where a district can be formed, specific regulations need
to be established regarding the procedures for establishing such a district. This
may cover notice requirements for landowners, hearing requirements for the public,
assessment formulae, payment plans, maintenance schedules, indemnity agreements,
appeals processes, provisions for lessees and all other matters related to organizing
and administering a BMD. It would be the proposed Division of State Beaches that
could make these rules. Many of these rules could be modeled after the regulations
and statutes for improvement districts in other coastal states, Oahu's improvement
district ordinance, or the Hawaii Community Development Authority's rules for a
district-wide improvement program.

F. Temporary Protection

The formation of a Beach Management District may take several months or
over a year, depending on the financing and type of project to be undertaken.
During the time that it takes to implement a, shoreline protection project, the
ore, temporary erosion
landowner's property may be threatened by erosion. Theref
protection devices need to be allowed such as low sandbag bulkheads or low weir
groins. It would be the proposed Division of State Beaches that would investigate,
or cause to be investigated, the types of suitable temporary structures. The
Division would also make the guidelines and regulations for temporary shore
protection.

G. Applicability

A Beach Management District may be organized in the form of an overlay
district, an improvement district, or as a hybrid forin, using a combination of both
concepts. Overlay districts can be created that control or guide the types of erosion
control structures along the shoreline. A proposed Division of Beaches could help
the counties to develop guidelines for the initial design of suitable erosion control
structures for the particular beach sector. An overlay district could then be
established that forbids new or illegal erosion control structures, except for those
structures that are in compliance with the initial guidelines. Coastal homeowners
would then have the option of complying with the overlay regulation individually,

or in cooperation with other landowners, so that the cost of additional engineering
studies or the construction of the actual structures could be shared among many
parties.

It is anticipated that for a sand replenishment project, an overlay and
improvement district would be required. An overlay district may be necessary to
prepare the shoreline for subsequent sand replenishment. Before sand
replenishment takes place, as many seawalls as possible should be removed to
prevent wave reflection off of vertical walls. Waves reflected off these walls may
carry replenished sand offshore during storm events. Structures such as a buried
revetinents may be substituted for the removed seawalls. For a sand replenishment
project, the creation of an improvement district would also be needed so that the
costs can be shared by all beneficiaries of the project.

The fortnation of an improvement district along the shoreline is not feasible
for all beach sectors. Some beaches, such as on the north shore of Oahu have such
high wave energy or large seasonal changes that the use of sand replenishment or
offshore structures to protect coastal property would be too costly or impracticable.
In other sections of the coastline, the landowners may be so close to the surf zone
that the use of measures other than a seawall or revetment may not provide
adequate shoreline protection.

Since an improvement district is not suitable for all sandy shorelines, other
beach protection strategies or management options are presented in this report. In
later chapters there is a review of nonstructural and structural erosion mitigation
measures. While many of these options would be available to the homeowner only
through the establishment of a Beach Management District, some of the options,
such as gently sloping buried revetments could be implemented independent of
district formation. In Chapter VIII, regulatory strategies are considered as
additional means to manage the shoreline.

VI. NONSTRUCTURAL AND STRUCTURAL OPTIONS

A. Artificial Beach Nourishment

1. Concept. Artificial beach nourishment has not been extensively used in
Hawaii. Because of this a number of technological aspects of the procedures will
require further understanding before nourishment will see widespread use in the
State. It is the goal of this report to briefly review some of the aspects and
describe where filrther research is needed. Despite these weaknesses, beach
nourishment provides an effective local option for reversing the trend of beach
degradation.

Beaches can effectively dissipate wave energy, thus protecting the adjacent
land from erosion. Because of this, the U.S. Army Corps of Engineers (COE,
1984) classifies them as a type of shore protection for adjacent uplands when they
are maintained "at proper dimensions." Artificial beach nourishment accomplishes
this with sand harvested from another source (borrow sediment, or fill) placed on
the beach in such a way to widen the subaerial beach. This procedure, called
beach restoration, is preferable to the construction of a seawall or revetment as a
means of shoreline stabilization, provided funds are available, environmental
impacts are minimized and there is sufficient interest in maintaining a recreational
sandy beach environment (Noda, 1989; NOAA, 1990). Beach restoration enhances
the recreational, and thus the economic, value of the shoreline. Restoration also
increases public access and utilization of the coastal zone and its resources, and in
many ways restores the former environment while protecting the adjacent upland
from erosion. Extensive use of seawalls and'revetments, as will be discussed in
detail later, leads to beach degradation under conditions of long-term sea-level rise.

Beach restoration can be expensive. Large projects, such as the restoration
of over 10 miles of Miami Beach, run into the many tens of millions of dollars
(Miami: $64 million; Ocean City: $45 million). Smaller projects cost considerably
less depending on many factors. On the U.S. east coast, it is common to nourish
coastal segments'less than I mile long for under $1 million. Many of Hawaii's
beaches tend to be tied to restricted littoral cells with limited alongshore length, in
many cases less than I mile long, so that costs could be lower on a per beach basis
than for lengthy sandy coastlines. However this may be offset by cost increases
associated with the lack of technological infrastructure to support restoration
projects in Hawaii. For instance, there are no hydraulic dredging systems available

in the State, and the cost for importation from the mainland will be considerable.

Preliminary estimates for nourishing Waikiki Beach from nearshore marine
sand sources range from $12.50 per cubic yard to $24.50 per cubic yard (Noda,
1992). A total of 146,000 cubic yards of well-sorted, coarse white sand is needed
to restore three target sites at Waikiki at a cost of $1.825 million to $3.577 million
(Noda, 1992). Considering the economic value of Waikiki Beach, this is a very
reasonable cost. As we shall discuss later in the case study at Kahala Beach, beach
restoration can be performed in Hawaii with reasonable economy, and, once
restored, beaches can be economically maintained under rising Hawaiian sea-levels.

The placement of sand on a beach does not in itself stop a long-term erosion
trend (COE, 1984), and there are no guarantees that the newly restored beach will
exist long enough to justify the cost. Newly placed sand can erode gradually, or
be carried away in hours by a storm (NOAA, 1990).

Because the restored beach is likely to experience erosion, it will require
periodic replenishment at a rate equal to or even exceeding the original erosion
rate. In many cases the restored beach can erode more rapidly than the natural
beach due to the loss of the fine-size component of the borrow sediment, and losses
at the ends of the fill segment (Fig. 23). Erosion will be enhanced if the fill has
a greater component of fine grains than the native sand. The fact that a nourished
beach will erode leads to the need for establishing a schedule of periodic
renourishment of the beach. Artificial beach nourishment may consist of
stockpiling sand on the updrift end of a littoral cell that feeds the downdrift beach
through the natural process of longshorel transport. In most cases beaches are
nourished along their entire length. Still other beaches may require several feeder
sites with associated stabilizing structures.

A schedule of renourishment essentially sets the eroded beach "back in time"
by establishing the configuration of the beach planform at some point earlier in the
erosion history when the subaerial beach was wider. Existing theory supposes that
if the nourished beach is designed with compatible sediment, and the geometry of
the fill approximates that of the natural system, then storms, sea-level rise, and
periods of high-wave energy will continue to erode the restored beach at rates
equivalent to natural rates. If extensive losses occur at the ends of the nourished
segment, or if the fill is not compatible, then higher erosion rates can occur.

z
UJ
2 E
W Storm Erosion
100
W
_J z
0, . .

U.1
W Trend Line
C) 0 Nourishment Event
50
LL
00
z

0
0 50 100
YEARS FROM PRESENT

Contours

Losses from
End of Nourished ...
Region

Nourished Region -1---L- Losses of
Fine Material

Pre-Nourished
Profile

Figure 23. Erosion of a Nourished Beach. TOP: Line I is a depiction of the shoreline
displacement history of a nonnourished beach. The trend line is the average, long-term erosion
rate resulting mostly from sea-level rise. The irregular heavy line depicts erosional events (peaks)
resulting from storms and high wave episodes, and beach accretion events (valleys) wherein the
beach profile recovers following erosion. Line 2 depicts a nourished beach that theoretically
should follow the same long-term and short-term history, only it is offset in a fashion consistent
with the nourished beach width. The nourished beach is wider and therefore represents an earlier
(less eroded) state. MIDDLE: A simplistic rendering of a nourished beach. Sediment is lost by
offshore transport, and longshore eros ion of the ends of the fill. BOTTOM: The nourished beach
shed
t

g" n

pro file should be similar to the natural profile after a period of adjustment (Dean, 1983).

A controversial review of mainland replenishment projects concludes that the
amount of fill, the frequency of renourishment, and therefore the lifetime cost of
many projects is consistently underestimated (Pilkey, 1988). This report calls for
reevaluation of the predictive capability of current renourishment theory, and wams
communities contemplating nourishment projects that costs are tied to the frequency
of renourishment which should be predicted on an actuarial basis rather than on
existing theoretical grounds. The criticism levelled at present nourishment
practices, cites frequent examples of over-optimistic predictions of beach-fill
performance, and under-evaluation of the influence of storms on renourishment
schedules and costs. As this discussion (Houston, 1991; Pilkey and Leonard, 1991)
centers on mainland coastal systems, its direct applicability to island beaches is
unknown. But these debates throw into question the level at which current
understanding of beach processes and nourishment technology can accurately
predict fill performance. They are cause for caution. Planning a nourishment
project is not a rote exercise, and every consideration must be given to the factors
governing success.

Sea-level rise causes beaches to move landward, potentially threatening
fastlands that are developed. Beach nourishment is the only well-developed
engineering technique that can counteract this recession and still maintain the
recreational value of the beach. Nourishment is apparently a viable and successful
response to the losses experienced by Hawaiian beaches, but there are numerous
local factors that throw into question the validity of existing nourishment theory
with regard to performance prediction and design criteria.

Some of these factors include seasonal changes in the wave climate that can
alter the sand movement pattern, storms and particularly energetic wave conditions
that can accelerate erosion rates. One intense storm can accelerate the erosion by
decades. Another factor is that Hawaiian sand has unique characteristics, and these
can control the slope of the beach, and the stability of the fill. In addition,
nearshore circulation cells and permanent sand losses to offshore areas are related
to reef morphology and the island wave climate. All these factors, and others, will
determine the success or failure of any Hawaiian beach nourishment project. There
are no guarantees that a properly nourished beach will survive to the designed life,
but there are steps that can enhance the survivability of the beach and increase its
recreational value. These steps come into play in several phases of the project:
planning, sand selection, monitoring, and maintenance.

2. PI Establishing realistic design parameters for the fill is critical to
the success of the economic and performance aspects of a nourishment project. All
parameters of the fill project must be tuned to the direction and rate of longshore
and cross-shore sediment transport, to the equilibrium beach profile (the natural
geometry and slope) of the site, and to matching the granular characteristics of the
fill to the native beach sand. This requires planning.

Sediment transport parameters can be supplied by a comparison of surveyed
beach profiles from the site, and by a comprehensive littoral observation program
recording characteristics of the wave and nearshore current regime. Surveys should
be conducted at monthly intervals for at least one year, and preferably two or more
years prior to the restoration project. The surveying should extend offshore as far
as the active profile adjustment, which may be to the back-reef hardgrounds or an
approximate depth of 30 to 40 ft (or approximately 0.6 mile offshore) if there is
no reef Thus the surveying will consist of a marine component requiring use of
a boat, a high-resolution fathometer and a precision navigation system. While a
comparison of historical aerial photographs of the site will provide estimates of the
direction of transport, and the general rate of beach accretion or erosion, these will
be averages of data spaced years, even decades apart. Only long-term,
high-resolution beach profile survey data can supply the beach slope, the
equilibrium beach profile to be anticipated when the fill equilibrates, and the
specific annual rate of erosion that was acting on the natural beach and thus may
be expected to act on the fill.

The equilibrium beach profile concept (Dean, 1983) idealizes natural
variations in beach slope and sand characteristics under a steady wave field to
describe an average beach profile. The concept is widely used because it is useful
in predicting the final configuration of a fill segment after it has shifted its
geometry to establish equilibrium with the ambient wave energy. In order to
minimize offshore sediment transport, the geometry of the placed fill should
approximate the equilibrium profile of the beach. An empirical description of the
average profile of 502 mainland beaches on the Atlantic and Gulf coasts forms the
basis for the theory (Dean, 1977). The theory, then, is derived primarily for quartz
sand beaches under continental shelf-type wave fields. The technique employs a
scale parameter that depends primarily on quartz grain size. The applicability, of
existing equilibrium profile theory in Hawaii should not be taken on assumption.
The entire theory hinges on the behavior of sand grains in the water column and
Hawaiian beach sand is substantially different from the quwz beaches forming the

underpinning of the theory. It is likely that minor modifications to the theory
would make it applicable to Hawaiian beaches, but the absence of a beach profile
database for the State make this a nontrivial matter. The theory is empirically
based) meaning that it relies on extensive field data. Also, although modifications
to. the theory may be minor, the impact of those changes may be significant in
terms of the predictive ability of the technique.

Planning should incorporate a recognition that the restored beach will
undergo an initial period of adjustment toward the natural equilibrium profile.
Although the subaerial portion of the beach can decrease and the beach width
narrow, sand relocated during this period of adjustment is thought to stay within
the active beach zone (NRC, 1987). However, Hawaiian beaches tend to suffer
permanent sand loss to large offshore feeder channels and sand fields, some of
which cut through the reef and carry beach sand into deeper water. These sand
channels and fields must be identified with a combination of field scuba
investigations and aerial photography. The profile monitoring scheme should
establish as one of its primary goals the extent to which local sand channels and
reef morphology influence the beach erosion and accretion characteristics. The
planform, and slope of the fill should be designed with a recognition of the
morphology and location of offshore loss sites in order to minimize their influence.

An additional element of planning concerns adequate characterization of the
seasonal wave climate and the occurrence of littoral sediment transport cells. These
develop when waves construct complex nearshore current fields that control sand
movement. Littoral cells can change on a seasonal basis as the wave approach
direction shifts (Moberly and Chamberlain, 1964) and previously accreting sites can
erode. A nourishment project should take seasonal sand transport trends into
account in the planview design and slope of the fill. This is also a necessity in
developing an accurate prediction of the fill performance, and renourishment
schedule.

3. Sand. Sediment used to nourish a beach must match the physical
characteristics of the native beach sand. It is common practice to assume that an
average native grain size can be defined using samples of sediments from the active
beach profile. Borrow sediments are deemed acceptable when the average fill grain
size matches that of the beach to be nourished. However, a body of sediment
typically consists of a more complex distribution of grain characteristics than can
be effectively captured by an average particle size. Sediment grain characteristics

that influence the performance of the nourished beach include: grain geometry, fill
sorting (grading), fill size skewness, grain mineralogy, and organic content.

Grain geometry, size, and I 'ithology are determinants of grain fall velocity,
which is the behavior of a sand grain suspended in the water column. Grains with
high fall velocity tend to settle quickly to the bottom. Under a given wave and
current energy, grains with high fall velocity are more resistant to erosion, thus
enhancing the stability of the beach. In fact, the average fall velocity controls the
geometry and slope of the beach (the equilibrium beach profile). If the fill fall
velocity characteristics do not match the native sediment, then the equilibrium
profile established by the restored beach can differ from the design, and from the
native beach. A nourished beach with a low average fall velocity can erode faster
than the native beach, shortening the life of the project.

One influence of fall velocity on the nourished beach is loss of fine
sediments (low fall velocity) due to their instability under a given wave field. If
a substantial portion of the fill sand has a low fall velocity, then this sediment will
be placed into suspension and carried seaward to where the lower wave energy
allows deposition to take place. The performance of such a nourishment project
would be relatively poor, suffering from the loss of a significant percentage of the
placed sand. It is possible to calculate an "overfill factor" (COE, 1984) which will
predict the amount of fill that will be lost under this process, and plan for the loss
by overfilling the nourished beach with a compensating volume. This, however,
may not be, an environmentally benign technique given the potentially huge
turbidity cloud that could emanate from the beach and the light-dependent nature
of coral reef communities. In Hawaii, given the fine micrite (calcareous mud) that
is found in many offshore sand Aeposits, a nourished beach with a substantial
overfill factor could potentially leach a turbidity plume for months to over a year
and could be liable as anonpoint-source pollutant.

Dean (1983) reports that if the fall time of suspended fine sediment is greater
than the wave period, T, then that sediment will be carried seaward beyond the surf
zone. Unstable beach grains with a fall velocity, w, will be suspended to some
fraction, B,1 of the depth, h. For the criterion [w < B (h/T)] these grains will
erode from the beach and probably be carried in suspension seaward through the
surf zone. At a suspension height Bh of 10 cm and a wave period of 10 sec, a
grain with a fall velocity of less than I cm/sec would be eroded from the beach.
For quartz sand this corresponds to a diameter of 0. 1 mm, but for calcareous beach

sand the size is unknown and the criterion is unquantified. Clearly, this would be
a simple procedure and should be a required exercise in the planning phase of
Hawaiian restoration projects for characterizing potential fill sediments. Olsen and
Bodge (1991) have determined that aragonitic sand has a settling behavior
equivalent to a quartz gram which is 1.36 times coarser. Because calcite has a
specific gravity of 2.71, less than that'of aragonite (2.95), the calcitic foraminifera
that make up 80% of the carbonate beach sands in the State will behave like an
equivalent quartz sphere somewhat less than 1.36 times coarser. Other components
of carbonate sands here are aragonitic, and some are calcitic. The distribution of
grain equivalent settling velocities in a fill candidate should be determined in order
to assess fill performance under seasonal wave conditions.

Hawaiian beaches are composed of a variety of sand types, none of which
is quartz, the dominant continental sand (Moberly et al., 1965). Little is known
about the influence of carbonate (calcite and aragonite), heavy mineral, or basalt
fragment sand grain fall velocities on beach equilibrium profile characteristics, or
on the performance of restored beaches. Standard engineering procedures regarding
this design parameter should be used cautiously on Hawaiian coasts as they are
developed with the assumption that the sand is quartz (James, 1975).

The majority of restoration projects in Hawaii will involve carbonate sand,
which, in the presence of acidic freshwater efflux, has a tendency to develop a
cement matrix and form carbonate sandstone (or beachrock) (Fig. 24). Although
not well understood, cementation seems to result from the percolation of acidic
freshwater through the beach sand (from either rain or groundwater) causing
solution and then deposition of a secondary, carbonate matrix. Cementation may
be accompanied by consolidation with the presence of a.high silt fraction. The silt
promotes tighter packing of the sediment giving the beach a hard unpleasant
surface. Why some beaches form beachrock and others do not is not known. The
restored beach at Fort DeRussy in Waikiki is known for its tight packing and hard
surface. Ko Olina Resort near Barbers Point has artificial beaches that are both
tightly packed and partially cemented. Little is known about the tendency for fill
sediment to lithify, but the process is at least partially controlled by grain
parameters (mineralogy, sorting, skewness) and pore water geochemistry.

Numerous documents (summarized in Dollar, 1979; Noda, 1991) report on
Hawaiian sand resources, concluding that terrestrial reserves on Oahu are in the
final stages of depletion, and that marine resources offer viable solutions to the

7-W

Mild

Figure 24. Beachrock. TOP: Cemented carbonate sands at Kahuku Beach, Oahu. This deposit
formed at present mean sea level. The geometry, lithology, sorting, and bedding of the sands
indicate that this is a former beach. Bo'rrow Three individuals stand on tabular beachrock
at Mahle Pt. on the windward coast of Oahu. Tile recreational beach here has been lost due. to
stabilizat ion. Sections of the former beach are preserved as beachrock in the intertidal zone,
presurnably they are sites of former freshwater efflux.

Table 4: Summary of Oahu Sand Resources (Moberly et al., 1975)

SOURCE VOLUME QUAL I TY IMPACT*
(Millions of cubic yards**)

Total Likely to For component For beach
source be useful of concrete restoration

COASTAL'ZONE, OAHU

Onshore

Alluvium, colluvim,
and glacial drift 0.8 0 poor to fair very poor slight to severe

Raised reefs (to be
crushed) 400 4 (7) very poor very poor slight to medium

Llthlfled dunes (to
be crushed) 14 4 very good good slight to severe

inactive dunes and
old beach ridges 15 2.7 fair to good fair to very slight to
very good severe

Beaches above MLLW 10.3 0 fal.r to good to very severe
excellent excellent
Off:hor:.s
eac and other
7;ar
,;hore to 9 -
depth 24 0 fair to good to slight to severe
excellent excellent but generally
9 m to 18 m (30' to unknown
609 depth 8 (7) 4 (7) unknown unknown slight

18 m to 91 m (60, to
3009 depth S20 S2 (?) unknown unknown very slight

Dredged reef (to be
crushed) 4,100 20 (7) poor poor very severe

INLAND OF T14E COASTAL ZONE, OAHU

Alluvium. colluvium,
and glacial drift 200 0.1 poor very poor very slight to
severe

Basalt (to be crushed) 800,000 320+ good poor slight to severe

IMPORTATION TO OAHU

From Neighbor Islands
(principal sources)
kal 3.2 0 excellent very good slight. If
Papohaku, Molo careful

Kans. Kauai 14.5 10 fair to good fair to slight
Central Maui (to be very good
crushed) 640 200+ very good good medium to severe
Penguin Bank 350+ 35 M unknown unknown very slight

From Outside the State
America large none excellent poor to fair none to Hawaii
Australia very some excellent poor to fair pone to Hawaii
large
pew Zealand, South- very some excellent poor to fair none to Hawaii
east Asia, etc. large

*Probability of unfavorable impact on the natural environment due to exploitation of the sand
**I cubic yard " 0.76 m3 or about 1.3 tons
77

need for commercial sand (Fig. 25) (Moberly et al., 1975; Table 4). Research on
offshore sands,, conducted jointly by academic units at the University of Hawaii and
private enterprise concerns with State and Federal Rinding (Dollar, 1979; Noda,
1991), has established that mining marine sands is economically and
technologically feasible (COE, 1984). When conducted at carefully selected sites
under rigid monitoring, marine sand mining can be environmentally benign
(Maragos et al., 1977), although this is still an area of concern (Noda, 1991).
Approximately 4 billion yd' of sand have been identified in waters less than 300
ft deep around the State. However, early successes in the Hawaiian sand mining
industry never reached full commercial potential because of special interest groups
(Dollar, 1979) and a complex array of regulatory obstacles. It is by special act of
the Legislature that the mining related activities for Waikiki restoration are allowed.

Recent investigations at Waikiki (Noda, 1991) conclude that proximal marine
sand reserves, dredged from offshore and hydraulically pumped through a pipeline
onto the adjacent beach as a slurry, provide the least expensive and most
logistically sound option for restoration. Ten sources of sand were compared,
including commercial sand from Australia, Maui, crushed coral from Barbers Point,
submarine deposits offshore of the Honolulu Airport Reef Runway, offshore of
Waikiki, and deposits on the Penguin Bank offshore of Molokai. Although there
are concerns regarding sand color, gradation and quantity, the prime candidates
were deemed to be the shallow nearshore deposits at the Reef Runway and at
Waikiki for a cost of $12.50 to S24.50/yd 3. Deep offshore sand deposits, or sand
from outside the State are estimated to be considerably more expensive.

Cementation may affect the availability of offshore sand bodies for fill.
Because some offshore sands are former beaches now drowned by sea-level
movements, many of them have been exposed to acidic freshwaters. While there
has been extensive geophysical research on the location, size and geometry of
offshore sand bodies of Oahu and selected other Hawaiian sites (Moberly et al.,
1975), few of these potential resources have been thoroughly sampled. It is
uncertain which are unconsolidated sand and which are lithified beachrock. The
sand source investigations for the Waikiki Beach restoration project (Noda, 1991)
discovered that additional improvements are needed in both geophysical surveying
and sampling techniques before offshore sand deposits can be adequately mapped
for confident resource assessment. Attempts to physically sample offshore sands
for Waikiki fill discovered that cementation and consolidation was extensive,
predictions of grain size characteristics were frequently wrong, and the predicted

to 15 KM

0 A H U

0 5 10 15 KM
WAIMEA LAIE 0 5 10 M1

-mow

MOKULEIA

KAHANA

0 A H U

KAILUA

SAND
ISLAND

KOKO HEAD

Figure 25. Offshore Sand Deposits. TOP: Marine sand bodies located between the present
waterline and 60 ft water depth. BOTTOM: Deeper marine sand bodies between 60 ft and 300
ft water depth. The section between Kailua and Koko Head was not surveyed, and between
Waimea and Laie surveys lack detail.

thickness of unconsolidated deposits was nearly always overestimated.

4. Monitoring. A crucial aspect of any beach restoration project is the need
to monitor the performance of the fill, and the influence of the project on adjacent
beaches and the adjacent reef The practice of beach restoration is still an evolving
science and many factors governing the success or failure of the project are as yet
still undefined. We do not know, for instance, the influence of carbonate sand on
beach geometry. We lack understanding of where beach sands end and offshore
sands begin. Little to nothing is known regarding the influence of fill on reef
communities in the proximity. What are the conditions of fill sorting and size
skewness that lead to optimal performance, and how do we apply the parameter of
grain fall velocity in best selecting high quality fill? What are the proper gTain size
and density criteria for a successful fill? How does a nourished beach affect
adjacent beaches, and to what extent is offshore reef morphology a critical factor
in fill perforinance? What are the influences of shoreline exposure and seasonal
wave climates9

These and many other critical data on nourishment are best obtained through
long-term profile monitoring and frequent bottom observations and sampling, at a
high-resolution spatial and temporal scale. Early nourishment projects in the State
will serve as models for latter ones. They will also provide data for defining many
of the necessary parameters. The Corps of Engineers (COE, 1984) and numerous
independent researchers (Dean, 1983) call for stricter monitoring programs to
address these questions. Despite this, many nourishment projects go unmonitored,
and the opportunity to obtain valuable data is lost. Hawaii has a chance to break
new ground, and strengthen the chances for successful restoration by requiring
clearly defined monitoring protocols with every nourishment project.

5. Maintenance. The need for periodic renounishment of the beach fill should
be recognized by those responsible for funding the project. A longer-term
commitment to the maintenance of the restored beach is an integral part of any
restoration project. Procedures for calculating a renourishment schedule are
provided in COE (1984), and discussed in Pilkey (1988) and Houston (1991).
Regardless of the debate centered on the veracity of these projections, they are
mainland projects and have little meaning in an island environment. Hawaii is on
untested ground when it comes to predicting the life and perforinance of artificial
beach nourishment.

The factors that will influence fill stability will change depending on the
orientation of the coast, the season, the width of the reef platform that dissipates
wave energy, and, of course, the granular characteristics of the fill. Beyond the
influence of sea-level rise and seasonal/annual wave climate effects, the most
important determinant of fill stability is storm frequency and intensity. Hurricanes
affecting Hawaii (Fig. 26) produce a number of detrimental effects on beaches.
High winds drive waves and pile water against the coast raising mean water levels
as much as 5 ft. The low atmospheric pressure associated with hurricanes can
cause the water surface to rise. If this is superimposed on a high tide and the surge
generated by large waves, a beach can be completely drowned for several hours.
The waves are not only higher, but the deeper water at the coast causes them to
break closer to shore, carrying offshore sand resources beyond the recovery point
of fairweather waves that restore the beach. The entire profile tends to shift down
and sand is lost from the beach to compensate for the loss offshore. The result is
a pennanent reduction of beach volume, and severe beach erosion.

Storm erosion can be worsened if the back-beach region is structurally
hardened. Seawalls and revetments will reflect the ston-n-wave energy during the
period in which a beach is covered by high waters, enhancing the erosive power
of the waves. For this reason, existing seawalls and high-angle exposed revetments
should be removed prior to nourishing a beach. If not, the entire fill could suffer
severe erosion in a drowning event such as a tsunami, a hurricane, or a tropical
stonn. Each of these meteorological or geophysical events can lead to reflected
wave energy off existing structures. It is worth considering replacing protective
structures with bunied, low-angle (1:3) revetments as a means of protecting- adjacent
upland property over the short-term.

How often these events will hit Hawaiian coasts is a matter of speculation
(see Bretschneider and Noda, 1985), but their occurrence governs fill life. A
schedule of renourishment will have the rate of sea-level rise (discussed later) and
landward recession rates as the primary pacemaker for the frequency of
renourishment. The occurrence of hurricanes and tropical storms will interrupt this
schedule at irregular, unpredictable intervals and require renourishment at higher
frequencies than otherwise. Depending on the shoreline exposure, the interannual
occurrence of particularly large north Pacific swell, southern swell, Kona storm
waves, and northeast trade waves will also influence the renoun'shment schedule
(Table 5).

:4 Fico Tropical disturbance ............
Jul 78
Tropical depression ............
00
3 Tropical storm ------
PACIFIC OCEAN Hurricane

lwa
Nov 82

Dot
Delia Aug 59
Sep 57
Hawaiian
Island
20* -

..........
Doreen
Jul-Aug 73 ik Nina
Nov-Dec 57 ----------

Celeste
Aug 72
100

1800 170OW 160* 150' 140*

Figure 26. Hurricane Tracks. Hurricane storm tracks between 1957 and 1982 (after Noda, 1989).

Future Sea Level .7 @_Shorellne Moverne
Steep Slopes,I Present Sea Level
ent lopes

Figure 27. Coastal Inundation. The contour technique of determining coastal inundation due to
sea-level rise (NRC, 1987), wherein shoreline movement and configuration depend on land slope.
This method is only recommended for coasts with immobile substrates, such as basalt, coasts.

Table 5 - Renourishment Frequency Factors.

EVENT EROSIVE POTENTIAL* EFFECT ON
MAINTENANCE
FREQUENCY

Sea-level rise High (not recoverable) 5 Years to Decadal
Hurricanes High (mostly not 5 Years to Decadal
recoverable)
Tropical Storms High (partially 5 Years to Interannual
recoverable)
North Pacific Swell Moderate (usually Interannual to Annual
recoverable)
Southern Swell Moderate (usually Interannual to Annual
recoverable)
Kona Waves Moderate (usually Interannual to Annual
recoverable)
Trade Waves moderate/Low (mostly Interannual to Annual
Irecoverable) I
*recoverability: likelihood of subsequent fainveather waves to reconstruct a beach with offshore sand
eroded by each event

6. Effect of Sea Level Rise. Sea-level rise leads to shoreline recession due
to a combination of inundation and erosion. Part, of the maintenance procedure is
to project future shoreline configuration due to sea-level rise. A number of
techniques exist for this, many of which are reviewed in Komar (1983), NRC
(1987, 1990), and Pilkey and Davis (1987).

The contour technique (Kana et al., 1984) assumes that no planform
alteration of the shoreline will accompany sea-level rise, thus a new shoreline is
directly a product of passive flooding. Slope is the controlling variable (Fig. 27)
and steep shorelines experience little flooding while gentle slopes undergo greater
flooding as the inland excursion of the waterline is enhanced. This implies that the
shoreline substrate is immobile, and that natural coastal processes are no longer
active. It was under these assumptions that the report on the effects of sea-level
rise in Honolulu was prepared (CZM, 1985). In Hawaii, these conditions will only

apply on basalt coasts and should not be assumed for any sedimentary shoreline.

Another technique is the widely applied "Bruun Rule" (Bruun, 1962; NRC5
1987). The Bruun Rule is based on the equilibrium profile concept mentioned
earlier, where a statistical average beachface geometry is assumed to represent a
sandy profile at a particular water level. Dean (1977) investigated the quantitative
expression for the profile proposed by Bruun (h=Ax'; where h is water depth,
x, is the horizontal distance from shore, and A is a constant for each profile) and
found the expression was correct as an average for 502 quartz sand beach profiles
on the mainland Atlantic and Gulf coasts. He also deterinined that the profile
shape parameter A, was a function of grain stability under a given wave field
(grain fall velocity). The Bruun Rule assumes that profile displacement in the
landward direction is a direct function of sediment loss from the beach berm and
beach face, and equivalent deposition on the offshore portion of the profile. Thus,
shoreline recession due to sea-level rise takes place by the transfer of sediment
from the beach to the adjacent offshore region. The shoreline adjusts landward by
a given lost sand volume, and the offshore adjusts upward by the same volume
(Fig. 28).
The Bruun Rule assumes that sea-level rise causes shoreline recession in all is
cases, and that the sediment volume lost from the beachface equals the sediment
volume deposited offshore. Thus, the Bruun Rule suffers from several short-
comings. The possibility of beach accretion is eliminated, permanent sediment
losses due to suspension of finer sands are not considered, longshore influences are
neglected, and the considerable effects of storms and high wave events are not
treated. In addition, the requirement of offshore deposition does not allow for
water deepening due to sea-level rise, which would otherwise tend to increase the
incident wave energy and enhance beach erosion. Because of these inadequacies,
an application of the Bruun Rule to determine the effect of sea-level rise on
beaches provides only a partial description of the true probable impacts. Despite
this, it is widely accepted and frequently used as a planning tool. The Bruun Rule
relates shoreline recession, R, and sea-level rise, S, in the expression:

R = S [W/ (h + B)]

where W is the width of the active portion of the profile adjusting to sea-level
change, h is the limiting depth of the active profile, and B is the beach berm

R1 W
Beach
Sea level Initial sea level
after rise
Bottom profile /I Itial bottom profile
after sea h
level rise
b' S

s = s" Umiting depth
b=W between predominant
nearshore and
offshore material

Figure 28. The Bruun Rule. The Bruun Rule relates shoreline displacement to sea-level rise by
assuming that a volume of sediment eroded from the beach will be deposited immediately
offshore without the loss of suspended material or the influence of longshore currents.

PREDOMINANT
WAVE DIRECTION
AVERAGE LONGSHORE COMPONENT AND MAGNITUDE AVERAGE LONGSHORE COMPONENT
OF WAVE ENERGY (PLUS DIRECTION) OF WAVE ENERGY 0AINUS DIRECTION3

BREAKWATER HEIGHT
WAVE DIFFRACTION LENGTH SPACING AND POROSITY
PATTERNS

ACCRETED
Li SHORELINE
UPDRIFT AND ox
ZO LITTORAL
DOWNDRIFT
oRT RATE
TRANSP
SHORELINE
IMPACTS SEDIMENT
CHARACTERISTICS IGINAC:"'.
0 OR
SHORELINEN

Figure 29. Plan-view of a Detached Breakwater. Design considerations for a segmented, detached
breakwater (Pope, 1986).
@HORELI N"

TRA

height.

Applying the Bruun Rule for a typical Hawaiian shoreline, we can use the
example of Waimanalo Beach on Oahu which has a berm height B of
approximately 2 in (6.6 ft) and active sand movement h to a depth of 6 in (19.7 ft)
(the reef depth). W can be estimated using A=O. I in" (NRC, 1987) for the beach
profile expression. Thus, the active portion of the profile adjusting to sea-level
change is W= (8/0.1)" = 716 in (2349 ft). The recession rate multiplier in (1),
W/(h+B), is 716/8=89.5. Using a rate of sea-level rise (S) of 0.62 in/dec. for
Oahu (Chapter II-Table 3) yields an estimated beach recession rate of 4.6 ft/dec.
under the present rate of sea-level rise. Under the projected submergence rates for
next. century (2.42 in/dec.: Chapter 11) this increases to 18.0 ft/dec. (Table 6).

In Table 6, the known present-day rate of sea-level rise (column 2) is used
with the Bruun Rule to predict the present-day rate of island-wide average beach
recession (column 3). Comparing this to the average of measured eroding sites

Table 6 - Beach Recession Predicted Using The Bruun Rule

Present Predicted Measured Projected Projected
Sea-Level Recession MOESE' 91 Sea-Level Recession
Island Rise

Tide Gauge Bruun Rule Aerial (IPCC, 1990) Bruun Rule
Trend Photos

Hawaii 1.55 in/dec. 11.6 ft/dec. 5.9 ft/dec. 3.3 5 in/dec. 25.0 ft/dec.

Maui 0.97 in/dec. 7.2 ft/dec. 12.5 ft/dec. 2.77 in/dec. 20.7 ft/dec.

Oahu 0.62 in/dec. 4.6 ft/dec. not avail. 2.42 in/dec. 18.0 ft/dec.

Kauai 0.69 in/dec. 5.2 ft/dec. 5.9 ft/dec. 2.49 in/dec. 18.6 ft/dec.

(MOESE, 1991; column 4) shows that predicted and measured recession rates are
closely matched for Kauai. For Maui, the Bruun Rule underpredicts the measured
recession rate, and for Hawaii it overpredicts the recession rate. The agreement for

Kauai may be fortuitous, and the disagreements are likely the result of local factors
(i.e., extensive stabilization on Maui) and the lack of island-wide coverage for
Hawaii in MOESE (1991).

Beach nourishment offers a means of effectively counteracting the recession
caused by sea-level rise. To maintain a stable shoreline, the annual volumetric rate
of nourishment, V, is equivalent to the annual rate of recession R, multiplied by
the total vertical height of profile adjustment (h+B), so that

V = R (h+B) (2)

The volume of sand per unit shoreline length necessary to counteract beach
recession due to sea-level n*se, can be calculated for present-day rates of sea-level
rise. This is performed using the Bruun Rule-predicted recession rates given in
Table 6. The procedure is also useful for determining nourishment needs under
ftiture accelerated sea-level rise. This is done by employing the Bruun
Rule-projected recession rates. These nourishment needs are readily converted into
cost estimates assuming the price of sand used for the Waikiki Beach restoration
project.

The Bruun Rule is the basis for the estimates in both Tables 6 and 7. Despite
its deficiencies, it provides a means of making reasonable estimates of future beach
recession trends and nourishment costs. For instance, to maintain a given beach
width on a segment of shoreline 2,500 ft long will cost approximately $14,000 per
year in renourishment expenses. If there were 25 properties on that coastal
segment, the cost becomes an annual fee of approximately $560 per property.
Considering Hawaiian beachfront land values, this is a minor fraction of the total
lue. Expressed as an annual percentage of the property value, shoreline
property va
stabilization by beach nourishment becomes a reasonable cost of living on the
coast.

Table 7 suggests that maintaining the roughly 65 miles of beach on Oahu in
their pr esent condition by nourishment under present rates of sea-level rise will cost
approximately $1.9 million per year. For a five-year renourishment schedule the
cost is $9.5 million every five years. Under accelerated rates next century, the
annual cost w*ll be $7.5 m*ll'on and the assoc'ated five year renounishment cost
$37.5 million.

Table 7 - Island Average Annual Beach Nourishment Requirements*
per foot of beachfront

Island For present-day For projected Nourishment Nourishment
sea-level rise sea-level rise Costs/foot of Costs/foot of
(in cubic (in cubic beachfront beachfront
yards/foot) yards/foot) Present Rise Projected Rise

Hawaii 1.12 2.43 $14.00 $30.37

Maul 0.70 2.01 $8.75 $25,13

Oahu 0.45 1.76 $5.63 $22.00

Kauai 0.51 1.79 $6.39 $22.37
Assuming $12.50 per cubic yard

B. Structures Commonly Associated With Nourishment.

Because of the complexities inherent in the physical processes governing
sand movement on the coast, it may be advantageous to alter the wave field and
the nearshore current pattern with a strategically placed structure such as a detached
breakwater, or a filled terminal groin. These should only be used in situations
where the characteristics of the wave field are understood in detail, and where the
structure of choice will clearly enhance the lifetime of the restoration project
without compromising the integrity and vitality of adjacent coastal environments
or posing a threat to the safety of those using the coastal zone.

1. Detached Breakwater. A detached breakwater can be an effective means
of attenuating wave energy on the beach, creating a wave energy shadow zone (Fig.
29). Because longshore sand transport continues outside the lee of the breakwater,
drifting sand brought into the shadow zone can be deposited, and localized beach
accretion can occur. If the localized accretion extends beyond the trend of the
adjacent coast, it is called a beach salient. If the accretion continues to the point
that the salient attaches to the offshore breakwater, it is called a tombolo. The
concept of a detached breakwater imitates the natural wave attenuating effect of an
offshore reef, sandbar, or small nearshore island. Since the sheltered beach traps
sand it has the potential to enhance erosion rates on downdrift beaches. For this
reason the offshore breakwater should only be used in conjunction with a beach
restoration project. In some situations a series of detached breakwaters can
enhance fill performance. Optimal spacing and offshore distance of the

breakwaters is a lunction of seasonal wave energy and direction and can be
calculated for a given coastal setting (Pope, 1986; COE, 1984).

2. Filled Terminal Groin. On a long reach of coast lacking discrete littoral
cells, the lifetime of a restoration project can be enhanced by placing a low, short
gToin at the downdrift end of the nourished portion of beach. If properly designed,
a filled terminal groin can stabilize the nourished volume yet still allow the normal
longshore transport to occur. The groin should be buried in the initial placement
phase of restoration, and it should be designed to allow sand to move both over its
top (a weir groin) and past its offshore end in order to minimize downdrift
erosional effects. Groins should only be used in conjunction with a restoration
project where it can be demonstrated that future renourishment needs will be
decreased by the structure, and where there will be no attendant downdrift erosion
(Dean, 1983). Renourishment of the updrift beach should occur when the groin
becomes exposed by erosion, and the beach downdrift of the groin is threatened
with enhanced erosion by longshore sand blockage. Groins will not be appropriate
in the majority of nourishment projects. Even the "leaky" groins we have described
here have the potential to cause severe downdrift erosion. Filled terminal groins
should only be considered in a nourishment project when the potential for negative
downdrift effects is minimal, when cost considerations are attractive, when the need
for future renourishment In decreased by the presence of the groin, and when
continual monitoring and future renourishment are guaranteed.

3. Perched Beach. An additional option receiving interest lately is the
perched beach. The perched beach raises the local profile with fill and an offshore
submerged sill that inhibits seaward sand losses. The sill acts as a barrier to
offshore movement of the sand transported as bedload in the hope that the profile
slope -is lessened, increasing the beach stability. It offers little' discouragement to
the suspended fraction, however and requires a downdrift filled ten-ninal groin to
limit longshore losses. Of concern Is the obvious limiting effect the sill has on
shoreward sand transport. Storm erosion would be permanent because the profile
would not be allowed to recover unless by longshore inputs. Little is known about
criteria such as appropriate depth and distance for the structure. Oversteepening
of the fill beachface due to continual losses and little recovery may instead result
from use of a perched beach. This may be a safety concern. Additional testing is
required before this concept is attempted.

4. Buried, Low-Angle Revetments. The presence of seawalls or steep

revetments in the backshore area of a nourished beach can pose a threat to the
stability of the fill by decreasing its performance characteristics during high energy,
high water-level conditions. In the event that a nourished beach becomes inundated
during a storm or hurricane (or tsunami), the enhanced energy reflection off the
seawall will exacerbate the erosion resulting from the storm. Even a buried seawall
is likely to become exposed in the course of the storin and act against the fill
stability. Sand grains will stay suspended in the high velocity, turbulent
floodwaters and will be transported offshore. It is preferable to destroy any upland
stabilization structures prior to nourishment.

However, some landowners may express concern over a lack of fastland
structural stabilization. In these cases a bun'ed revetment (Fig. 30) at an angle no
greater than 1:3 may be an acceptable alternative to a seawall or other high-angle
structure. The revetment will armor the upland and, if adequately buried, will not
pose as great a threat to fill stability. Features enhancing the benign influence of
a buried revetment on the adjoining fill could be a rough and semi-permeable
surface as a factor to enhance wave energy dissipation, and reduce reflection and
backwash if the revetment is exposed in a storm. Burial should first be under
packed and consolidated'soll, followed possibly by sand from the nourishment
project and heavy vegetation. Contingencies should be made for the repair, and
reburial of the revetment if any action (including wave erosion) results in the
exposure and deterioration of the structure. The structure should also be carefully
monitored to deten-nine its effect on fill stability under a range of conditions.

C. Vertical Structures.

There is active discussion among coastal scientists regarding the influence
of seawalls and revetments on the adjacent beach. However, there is a distinct lack
of long-term field studies to provide an uncontroversial indication of whether
shoreline hardening is a detrimental or benign agent under the influence of wave
forces alone. A number of short-tenn studies (reviewed in Tait and Griggs, 1991)
have investigated whether increased beach erosion and subaenial beach width
reduction occurs along hardened shorelines (Fig. 3 1). The majority of these
were inadequate in both spatial and temporal scope, and the data they provide is
highly site specific and tied to particular events. No studies of seawall or
revetment effects on Hawaiian shorelines exist.

Kraus (1988) reviewed the available body of literature on the potential

BURIED REVETMENT S%099

natural vegetation line
We aso-

beach berm

msi

quarrystone armor (1:3)
Z
gravel blanket 0.3 m thick
over regraded bank (1:3)

Figure 30. Buried Revetment. A low-angle buried revetment may be a short-term, benign method
of upland protection for coasts where relocation is not possible. This should only be used in
conjunction with beach nourishment, and where immediate repair and reburial is guaranteed if
the structure is exposed. Unless future beach nourishment maintenance is guaranteed, long-term
sea-level rise and shoreline recession will eventually require that this structure be removed or the
adjacent beach will be lost.

Seawall is placed well seaward on beach
profile-, a narrow summer berm exists. The
beach in front of the wall is very sensitive to
changes in sediment supply or sea level.

If there is net shoreline retreat, the area
behind the wall may become a peninsula.
obstructing longshore transport. Under sea-
sonal changes, the wall may similarly lose
the beach in front of it. project into the surf
zone, impound HELaral drift, promote down-
cc= erosion, and obstruct alongshore beach
(Griggs and Tait).

Figure 3 1. Seawalls. Long-term effect of seawall building on the beach profile (Tait and Griggs,
1991).

impacts of seawalls and revetments (Fig. 32). In the majority of cases, these
studies examined the immediate, short-term effects of hardening related to storms
and examined effects on a limited spatial scale. Kraus (1988) concluded that
where adequate sediment supply exists, the beach is not detrimentally affected by
hardening. But a beach with adequate sediment supply is either accreting or at
least stable, and a seawall would not be built on such a beach near the waterline
where it would interact with the nm-up or active wave energy zone. Clearly, a
stable or accreting beach will not provide evidence of the negative effects of
seawalls and revetments because the seawall will not be built in the swash zone.
Kraus also concludes that "on an eroding coast the beach in front of a seawall may
narrow and eventually disappear if there is an inadequate sediment supply." An
inadequate sediment supply is self-evident on an eroding beach. Thus, seawalls
eventually lead to beach loss on eroding coasts.

In a regime of long-term sea-level rise, such as in Hawaii, all coasts will
ultimately retreat landward. A seawall or revetment on a retreating beach will
eventually begin to interact with, and reflect wave energy. As we have shown in
Chapter 11, a natural beach that is receding landward will maintain a consistent
subaerial width and sand volume as it migrates landward. Such a beach will
remain a viable recreational and environmental resource, provided the migration is
not halted by hardening. In the presence of a landward structure, the landward
border of a beach will cease moving at the base of the structure, but the seaward
border will continue to migrate landward. With time, this leads to beach narrowing
and sand loss exacerbated by a number of processes and morphological features
observed by researchers. In a recent report by the- U.S. Army Corps of Engineers
(Tait and Griggs, 1991), all of the following effects have been observed in the field
and attributed to the presence of seawalls and revetments (Fig. 33):

a. Wave Reflection: incident wave energy is dissipated on a natural beach, on
armored coasts this energy is reflected, not dissipated. Numerous studies describe
reflected waves moving sand seaward where it is removed by longshore currents.

b. Scour Trough: a linear trough or erosional depression fronting a seawall or
revetment indicates sand loss from the toe of a structure, this often leads to
structural failure by undermining.

c. Deflated Profile: the lowering or erosion of the beachface due to general sand
loss along the entire profile fronting a structure occurs when waves interact with

WA VE

LONGSHORE BAR
CURRENT IN
EPTH
-HISTORICAL
'e@ PROFILE
INCIDENT
WA VES

IMPOUNDOWENI`@ POST-STVRM
PROFILE
PRE-STORM
PROFILE

BAR :V0,0td. deflated ?I
cc rld.wo'v
SEAWALL (bal d1solaced ?I

DOWNDRIFT
FLANKING
1 '.0?) REFLECrED
WA VES
tat'd'al

BAR

ERODED
UNPROTECTED
SHORELINE

"HISTORICA
SHORELINE
Figure 32. Seawall Impacts. Plan-view and profile view of seawall impacts (Kraus, 1988).

UPCOAST ACCRETION

ENDSCOUR

RIP CURRENT TROUGH

BEIA`7
OF N
IL ATIO

Figure 33. Beach Profile Impacts. Profile deflation, sand blockage, end scour, sediment loss (Tait
and Griggs, 1991).
SCOUR
D

the armor unit.

d. Beach Cusps: crescentic or semi-circular erosional embayments on the beachface
are associated with profile deflation and sand loss.

e. Rip Current Troughs: a trough or channel crossing through the surf zone has
been observed to form in front of hardened coasts, this feature acts as a conduit for
offshore sand loss.

f. End Scour: erosion of the unprotected beach adjacent to the end of a seawall
(flanking) is associated with profile deflation, and often leads to structural failure.

g. Updrift Sand Impoundment: a seawall interrupting littoral drift can trap sand on
the updrift end and lead to concomitant downdrift erosion and enhanced shoreline
recession and beach loss.

h. Storm-Induced Scour: sand loss due to increased turbulence and wave reflection
effects has been observed during high-water level and high-run-up periods
associated with storms and seasonal wave climates.

i.Post-Erosional Recovery: shoreline hardening can impact the ability of a beach
to recover lost sand following storm or seasonal erosion events, or longer-term
cyclical erosion, leading to pen-nanent sand depletion, and beach loss.

J.Higher Littoral Energy: increased longshore current velocities, and turbulence
related to wave reflection, leading to higher sediment mobilization and sand loss
offshore from a structure has been observed during storms and high wave periods.

k. Blocked Upland Sand Delivery: shoreline hardening prevents sand from moving
to the beach forin upland sources, such as the vegetated coastal dunes that are
common on Hawaiian shores.

Tait and Griggs (1991) state that the overriding factor in the impact of a
seawall on a beach is the long-terin shoreline trend. If a shoreline exhibits an
erosional trend, and some segment of that shoreline is fixed in position by a
seawall, then the beach will eventually disappear in front of the wall (Fig. 34). On
a stable shore, the wall will only affect the beach when storms, or seasonal
fluctuations in the position of the shoreline, expose it to wave attack. Everts

L
-TEP
ONG m EFFEM OF SEAWALL ON RETREA71NG SHORE

CASE L ERODIBLE BLUFFS OR DUNES, SEDUAENT DEFICIENCY AND SEA
LEVEL RISE. WALL AT BACK BEACIL

INMAL SHORE PROFILE

SHORE PROFILE AFTER SHORELINE RETREAT

Shoreline has migrated landward but beach
width is maintained as the bluffs or dunes
Ll ---- are croded (LI LO).

SHORE PROFILE AFTER SHORELINE RETREAT WrM SEAWALL

Shoreline has migrated landward and beach
width has narrowed (LI < LO) because
seawall limits beach retreat. The area pro-
tected behind the wall ran eventually
becorne a peninsula, obstructing longshore
drift.
LI

Figure 34. Seawalls. Long-term effects of a seawall (Tait and Griggs, 1991)

(1985) describes how armoring on a retreating coast, or one where fluctuations in
beach width expose the armoning to waves, leads to sand scour and beach loss, and
an increase in water depth and wave height at the shoreline.

Because it combines a thorough literature review with a relatively long field
experiment, the study of Tait and Griggs (1991), funded by the US Army Corps
of Engineers, is clearly the most comprehensive report on the problem of beach -
seawall interaction. They find that the factors controlling the type and magnitude
of beach response to hardening are numerous and interdependent. The variability
of beach response and the apparent dependence on a number of interconnected
factors requires that any evaluation of beach-seawall effects should be made on a
site-specific basis. They also conclude that if net retreat is occurring, a condition
that -characterizes the Hawaiian coast, then "eventually the beach in front of a
hardened shoreline will disappear. Such retreat is a function of a deficit in the
littoral sediment budget and/or relative sea-level nise."

It is notable that what Pilkey in 1988 called the "Great Seawall Debate", has
by 1990 become accepted as the Great Seawall Calamity. By this time, the
detrimental effects of seawalls on beaches are widely accepted and form a basic
as sumption of nearly all local, State, and Federal offices and programs concerned
with coastal zone management (with the exception of the Army Corps of
Engineers). For instance, the N.O.A.A. Coastal Programs Division (1990) has
taken a firm position against shoreline hardening:

"A seawall on a beach not only accelerates beach erosion, but also inhibits
the beaches ability to absorb storm energy, thus exposing structures (buildings) to
the full force of wind and waves.

"Erosion control structures have the ironic effect of accelerating erosion,
either in front of the development the structure is designed to protect, or
do w n dr ift. "

'Although seawalls and bulkheads may stabilize an eroding shoreline for a
time, normal and storm-wave action eventually strip away the beach infront of the
structure and scour out its base, causing the wall or bulkhead to fail. "

"Sound beach management requires that state and local governments limit
or prohibit erosion control structures, particularly vertical structures such as

seawalls and bulkheads.

There is little support, then, for the use of seawalls or exposed revetments
as shoreline stabilization measures because they result in the loss of the adjoining
beach and enhanced erosion on the adjacent coast.

D. Restrictions on Shoreline Structures.

Certain states, including Georgia, Maine, North Carolina and South Carolina,
restrict by regulation the types of erosion control structures along the shoreline.
In Georgia's Shore Assistance Act, the only type of shoreline stabilization allowed
is with low sloping porous granite structures or other techniques which maximize
the absorption of wave energy (Ga. Code. Ann. S12-5-238). In South Carolina, no
new erosion control structures are allowed seaward of a 40-year setback except to
protect a public highway (S.C. Code Ann. S 48-39-290). Existing erosion control
structures may not be repaired or replaced if 80% of the structure is destroyed
before June 30, 1995, 66% is destroyed between July 1, 1995 and June 30 2005;
or more than 50% is destroyed after June 30, 2005.

As shown in Chapter 11, and discussed in this Chapter, a major cause of
beach loss around the islands is attributed to stabilization of the shoreline. Several
previous studies have called for some restrictions on the use of vertical seawalls in
certain areas (Sea Engineering, 1991). This report is in agreement with other
studies which call for an investigation into the limitation on certain types of erosion
control structures.

One option that should be considered is a restriction on future seawalls or
revetments for large tracts of undeveloped land which have not been subdivided or
zoned for urban use. Without the use of seawalls or revetments to harden the
shoreline, landowners would need to plan natural beach instability into the design
of a coastal project.

For existing coastal development where the shoreline is natural, effort should
be made to utilize some soft approach, such as beach replenishment in conjunction
with some other structural options suggested in this chapter. These options would
J! require the fori-nation of an improvement district.
A

Where it is not technically, legally, or financially possible to form an

improvement district, shoreline stabilization devices such as gently sloping buried
revetments placed landward of the certified shoreline should be the preferred
erosion mitigation measure. These structures would reduce but not eliminate the
potential impacts on the sand beach. Numerous coastal studies have suggested the
use of buried erosion control structures to protect coastal property and minimize
impacts on the beach (DHM inc., 1990; Edward K. Noda & Assoc. 1989). The
Department of Land Utilization, City and County of Honolulu has required the
construction of gently sloping revetments inland of the certified shoreline for four
landowners at the southeast end of Lanikai Beach. The combination of the gentle
slope of the new revetments, along with the removal of previous erosion barriers
which protruded into the tidal zone resulted in the recovery of a lost beach. The
gently sloping revetments at southeast Lanikai are alternately buried by sand and
uncovered by erosion during the seasonal changes along this shoreline sector.

Regulatory restrictions on certain erosion control structures such as seawalls
or bulkheads, could be placed at the State or county level. Alternatively, the
restrictions can be imposed by the establishment of an overlay district with overlay
regulation. There are many advantages to restricting seawalls and bulkheads by
overlay regulation. These include the following: a) specific areas can be targeted
that require special attention; b) opposition from overlay restrictions may be less
than if similar controls were placed at the State or county level, since a smaller
group of landowners would be affected; and c) the counties may take the initiative
to establish regulatory restrictions, should the State fall to act. The disadvantages
of relying on overlay regulations to restrict seawalls or bulkheads is that: a) it fails
to provide a comprehensive solution to the pervasive problem associated with beach
loss and sea-level rise and b) it abdicates protection of the State beach resource to
the counties.

VH. FUNDING

One of the critical issues for any beach management district is who should
pay for the costs. The public may want the landowner to pay since it can
legitimately be claimed that the coastal homeowners create the need for less
harmful erosion control protection (see Figs. 2 through 6). The landowner may
want the State or county to pick up the tab since a beach management project
benefits all the public. The county would want the State to pay since the beach is
state land. The state may want the county to pay since the county can prevent
many beach erosion problems through their land use policies.

Many coastal states have grappled with the issue of funding in the
administration of beach management districts. The common theme for the majority
of districts is that there is a shared cost system with contributions from the
government and the homeowner. For example, in California, if Federal funds can
be obtained to pay for half of a project for beach erosion control, then it is the
policy of the State to split the remaining cost with the local government. In
Connecticut, beach erosion control projects that benefit the private littoral owners
are paid for in equal shares by the State, the local government and the coastal
landowner (Conn. Gen. Stat. Ann., Title 25-Water Resources, S 25-71). In Florida,
State initiated programs of beach replenishment are paid with 75% of the cost from
the State and the remainder from the local government (Fla. Stat. Ann. S 16 1. 10 1).
Money for the preliminary design and other costs of the project is derived from the
Florida Beach Management Trust Fund. In Maryland, the State payment for a
nonstructural erosion control project may not exceed 50% of nonfederal cost (Md.
Nat. Res. Code Ann. S 8-1007). In North Carolina, private landholders may
petition the State for grants that cover 75% of the cost of shore protection in the
nstance where public access is allowed and provided for (N. C. Stat. S 143-
215.71).

For Hawaii, a shared cost system is proposed. This chapter discusses
different sources of funding. After the discussion of funding sources, some
suggestions are offered about the allocation of costs within a Beach Management
District.

A. Sources of Funding

I Federal. One source of Federal assistance that should be investigated by

9-9

the State is appropriations under the River and Harbors Act (33 U.S.C.A. S 401 et
seq.). Specifically, section 426e of the Act provides for Federal aid in the
protection of shorelines. The Federal contribution for an erosion control project is
not to exceed one-half of the total cost of the project. Thus, there is the
requirement that the State or local government share in the funding of the project.

There are also provisions in the Act that allow shores other than public to
be eligible for Federal assistance, if there is a public benefit such as that anising
from public use. The Federal contribution is to be adjusted according to the degree
of public benefit. One state that has taken advantage of this Federal program is
Florida. Numerous beach restoration projects have been flinded with Federal aid.
Many of the projects include long stretches of shoreline that are backed by private
hotels. As long as the project has some public benefit, such as access to the beach
and use by the public, then the project may be eligible for Federal assistance (John
Housley, pers. comm., Army Corps of Engineers, Planning Division, Washington,
D.C.).

Under section 426g of the Act, the Secretary may authorize small shore and
beach restoration and protection projects, provided that not more than two million
dollars is allotted for any single project. Federal assistance under the River and
Harbors Act could play a major role in the formation and financing of Beach
Management Districts.

In the future, the State may have to establish, or be committed to, a
beachfront management program to be eligible for Federal assistance. Congress is
to consider the requirements that the State have guidelines for shoreline setbacks
based on a 30 year annual erosion rate, restrictions on erosion control structures,
and provisions for relocation before federal assistance is received (33 U.S.C.A.
426e) . These topics are covered in other chapters of this report.

Another source of Federal funding that should be investigated by the State
includes the use of erosion benefit payments under the Upton-Jones amendment to
the National Flood Insurance program. Certain coastal homeowners who are
covered under the national flood insurance program and threatened by erosion may
receive up to 110% of the value of their structure if they relocate inland or
demolish their structure. To receive the benefits, homeowners must be in a zone
of imminent collapse. There are other qualifications that are required to benefit
from this program that are discussed in Chapter VIII. Although benefit payments

100

under Upton-Jones would not be used in the formation of a Beach Management
District, this program could provide important financial relief to coastal landowners
who are endangered by erosion.

2. State. Many of the proposals outlined in this report are structured to
reduce the financial burden on the State. For example, there are suggestions to
seek Federal funding and to recover costs from landowners in proportion to benefits
imparted on their property through the establishment of improvement districts.
Nevertheless, a long-term commitment to beach preservation by the State will
require increased effort in the form of new programs and financial support. As the
trustee and caretaker of the coastal resource, the State should play the major role,
both financially and administratively.

A State that has made great effort to save its beach resource is Florida.
Florida is heavily reliant on its tourism industry and has made a real commitment
to beach preservation. Between 1965 and 1984, approximately 115 million dollars
were spent in the State on beach recovery techniques, primarily sand
renourishment (National Research Council, 1987). Given the high cost of real
estate and the high tourist revenues, it was easy to justify the projects on a cost-
benefit ratio.

In Hawaii, it is improbable to expect levels of ftinding similar to those in
Florida. Nevertheless, it is not unrealistic to expect a continuous source of revenue
from the State to pay for beach preservation programs. To allow continued loss
of beaches in a State where tourism is the number one industry will wind up
costing the State more in the long-term.

3. Counly. It is anticipated that counties will pay a small portion of the cost
for any beach improvement district. The counties should be made to pay at least
a token amount for two reasons. First, in the apportionment of cost for
improvement districts, allocation schemes are based on the amount of benefit
conferred. For an improvement district within a particular county, say for example
in Maul, it would be the residents of Maul who would benefit more than residents
outside the county. A second reason why the counties should pay a small amount
is that the counties may, through their land-use policies, prevent erosion problems
in undeveloped areas by planning for coastal erosion. If the counties were made
to pay for beach improvement districts, it would provide economic incentive for the
counties to plan for coastal erosion.

101

4. Assessments. Benefits from any public improvement can be classified as
general or specific. General benefits are those that accrue to the public at large.
Specific benefits accrue to a particular group of individuals. Using beach
renourishment as an example, one benefit from a wider beach would be improved
lateral beach access and increased recreational utility. These benefits are general
since they accrue to all beach users, regardless of whether they lived next to the
beach or many miles away. Another benefit from sand replenishment is that a
wider beach absorbs wave energy, thereby reducing the threat on adjacent land
from wave inundation and erosion. Furthermore, a beachfront home is likely to
increase in value if there is a wide, healthy beach in front that provides recreational
opportunities and some protection from the forces of nature. Shoreline protection
and increased value of the property are specific benefits since they accrue only to
homeowners who live along the shoreline.

Landowners who abut the beach would be major beneficiaries of a sand
replenishment project. In such a case, the landowner would receive general and
specific benefits. The theory behind an improvement district is that the landowner
is assessed a fee in proportion to the specific benefit conferred on the property.
Therefore, for any improvement project within a beach management district, a
special assessment for those landowners who live along the shoreline should be
made.

There are many assessment formulas that can be used, such as the linear
footage along the beach, the. area of land benefited by the project, the value of the
land next to the beach, the distance of structures from the shoreline, or a
combination of the above factors. A common method to apportion an assessment
is based on the front footage of -the land (Md. Nat. Res. Code Ann. S 8-1007).
Since the amount of protection from an erosion control structure or beach
replenishment project is proportional to the length of shoreline protected, linear
footage along the shoreline is a logical factor to consider in an assessment. In
addition, the cost of an erosion control structure or sand replenishment project is
proportional to its length along the shoreline.

Another alternative would be to base the landowner assessment on more
than one factor, say for example, length along the beach and value of the property.
By using value of the property, some consideration could be given to the individual
landowner's ability to pay. A proposed Division of State Beaches could work up
the specific cnitenia and formulas for the equitable assessment of the landowner.

102

A few points should be made about landowner assessments within the
context of the beach management district:

a) In any- improvement district regulation, provisions need to be made
for maintenance assessments. This is especially important for a sand
replenishment project where periodic renourishment is required.

b) In an improvement district, assessment charges are either payable
when due or in annual installments over a period of 10 to 25 years (See e.g.,
Md. Nat. Res. Code Ann. S 8-1006; N. C. Gen. Stat. S 153A-200; Revised
Ordinances of Honolulu, Chapter 24, Sec. 24-3.2). To encourage landowner
participation in a BMD, a program similar to that in Maryland should be
considered whereby low interest or no interest loans are offered in the
installment payment plan.

c) There is the legal requirement that money from assessments in an
improvement district must be used to pay for improvements in that district.
Therefore, it is suggested that assessments collected be held in a Special
Assessment Trust Fund until they are ready to be used.

d) There is a strong incentive for the coastal landowner to participate
financially in a beach management district. For many beach sections,
seawalls are being undermined by constant wave action. As sea level
continues to rise and protective beaches disappear, the cost to maintain these
structures will increase. Homeowners need other alternatives to protect their
properties. It is through an improvement district, where landowners share
the cost with the State and county, that other options to provide long-term
protection may be developed.

5. Tax Incentives, Credits and Fees. The primary purpose of taxation is to
raise revenues. However, tax programs and tax policy can also shape investment
decisions, which in turn, may affect development and land-use policy. From a
political viewpoint, the use of the word "tax" has a strong negative connotation.
However, innovative tax programs can be implernented which actually favor the
State, the public and the landowner. In fact, one of the tax programs was initially
suggested by a beachftont homeowner.

In this study, two tax programs are discussed that could lead to improved

103

beach management and significant revenues to the State. These programs are
offered not as recommendations, but as options the State mgy or mqy not pursue.
These programs, as well as others that provide economic incentives and
disincentives, should be investigated by the State as a means to raise revenue for
beach preservation projects. Each of these programs would require more study than
can be devoted to the topic in this report.

a. Tax Deductions. Two broad generalizations can be made about
beachfront homeowners. First, given the cost of beachfront property, many of the
homeowners are likely to be affluent. While no study was made to verify their
personal background, it is probable that many are professionals, who are familiar
with the use of tax shelters and deductions. An exception to this generalization
may be the case where there has been long-term family ownership of property, and
ownership has been transferred by inheritance.

Another generalization is that beachfront homeowners will go through great
efforts to protect private property from coastal erosion. As discussed in previous
chapters, the demand to protect coastal property is expected to increase because of
rising sea-level.

Based these generalizations, the State can tailor tax policy to increase the
level of funding by the coastal landowner for the capital improvements within a
BMD. For example, a State tax deduction could be offered to beachfront
homeowners who contribute more than their assessed amount to pay for the capital
improvements in a BMD. The assessed amount is determined by an allocation
formula (see next section).

The State and county would benefit from the tax deduction since the
increased contribution by the landowner may offset some of their cost for the
district improvements. The landowner would benefit since they are allowed a tax
deduction for improvement projects that protect their property. The public would
benefit because a public beach may be preserved or restored at minimum cost to
the State.

b. The Shoreline Property Transfer Tax. There is one major problem in
funding beach preservation programs. Coastal properties have risen astronomically
in price. At the same time, State and county budgets are squeezed just to pay for
basic public services. As coastal properties escalate in price, it becomes

104

prohibitively expensive for the government to finance programs for the acquisition
of rights-of-way or to develop a voluntary relocation program that features the
purchase of the underlying land. One way to alleviate this problem is to link the
cost of coastal property with the revenues for funding beach preservation programs.
This could be done with a small tax for the transfer of beachfront property.

The property transfer tax has been successful in buying open space in
Massachusetts (Steve Blivens, pers. comm., Massachusetts Coastal Zone
Management Program). For the islands of Martha's Vineyard and Nantucket, a 2%
transfer tax is placed on all property transfers. All houses on these islands are in
the coastal zone. Revenues from the taxes are placed in a special fund that is used
to buy open space along the coast. A significant amount of open space has been
purchased through this program.

There have been attempts in Massachusetts to extend the transfer tax beyond
Martha's Vineyard and Nantucket. Opposition to the tax comes from the real estate
lobby, which has argued that the transfer tax drives home prices down. For
Martha's Vineyard*and Nantucket this price effect is not apparent as most houses
have risen gradually in price since the tax went into effect. This is an indication
that market factors are the controlling factor in the price of property rather than the
small 2% transfer tax.

If a shoreline transfer tax was implemented in Hawaii, one concern may be
the potential impact on home prices. Some interest groups may argue that the tax
will have a rippling effect that causes rising home prices throughout the State.
Conversely, the real estate industry-and landowners would argue that such a tax
drives property prices down. Additional study would be needed to predict the exact
impact on home prices, or to formulate strategies to mitigate the problem.
Nevertheless, the experience from Massachusetts indicates that general market
trends related to the economic business cycle will ultimately control the price of
real estate.

Other jurisdictions across the country have modeled their land acquisition
programs after Nantucket's. Two new programs may soon be set up in Hilton
Head, South Carolina and the State of Washington.

The State of Florida also has a property transfer tax that is based on the use
of documentary stamps. When the deed to a property is transferred, a stamp of the

105

document is required to record the deed. The cost of the documentary stamp is
based on a percentage of the sales price of the property. Assessments from the
transfer tax are used to acquire land, or build low income housing projects (Kirby
Green, pers. comm. --Florida Division of Beaches and Shores).

For Hawaii, a property transfer tax should be investigated to help finance
the following:

1) capital improvements within a Beach Management District

2) a program of open space coastal land acquisition

3) a voluntary relocation program where State funds are coupled with the
FEMA Flood Insurance relocation money to provide economic incentive to move
threatened structures inland.

The shoreline property transfer tax is an option that the State should
investigate as a means to raise money for beach preservation programs. Such a tax
is believed to be a fair and non-burdensome request of the beachfront owner for the
following reasons:

1) The long-term homeowner could view the transfer tax as favorable. In
return for a minor transaction fee when the property is sold, the beachfront owner
may be able to benefit from two programs. First, a voluntary relocation program
could be developed whereby funds from the transfer tax along with Federal funds
from the Federal Flood Insurance program are'combined to provide, under certain
conditions, a form of insurance during erosion or storm events. Another program
that may benefit the landowner is that at appropriate localities, the homeowner may
be able to benefit from the capital improvements within a Beach Management
District. These capital improvements could be' financed, in part, with the transfer
tax. Thus, the transfer tax should not be viewed as a penalty on the beachfront
landowner. The tax will be used to pay for programs that benefit the State, county,
public and the private landowner.

2) In its natural state a receding beach does not wash away but simply shifts
inland (see, e.g., Fig. 2; see generally, Gilbert, 1986). Only after the shoreline is
hardened or stabilized is the beach likely to disappear. Hardening of the shoreline
is not required until a man-made structure is threatened by erosion. In a sense, the

106

coastal landowner creates the need for expensive erosion mitigation alternatives
that do not harm the beach. A shoreline tax would help pay for these alternatives.

3) The transfer tax for properties abutting the shoreline is not a burden for
long-term homeowners who plan to stay in their residences. The transfer tax may
affect the practice of short-term ownership and speculative purchases of shoreline
property-

4) It is only when the property is sold that a small fraction of the benefits
of living along the coast are recovered for the public. It may be questioned why
any benefit should be recovered for the public. A strong argument is that for
beaches that have disappeared or have been impacted by stabilization, private use
of the shoreline has resulted in a lost public benefit. Revenues from the transfer
fee can be used to recover some of the lost public benefit at the locality where the
property was sold, or at another suitable site.

5) It is because shorefront properties are so expensive that a voluntary
program by the State to acquire coastal land, relocate structures, and remove
seawalls would be difficult to finance without significant contributions from outside
sources. Thus, the transfer tax is suggested in this report. The transfer tax is
powerful since revenues from the tax rise as shoreline properties rise in value. In
addition, revenues from the fee are derived whenever a beachfront property is sold,
thereby insuring a steady and significant source of revenue is available for
programs that preserve the beach and protect the shoreline property owner. Finally,
a permanent small fee can raise a large sum of money (See example below).

In order to meet Constitutional requirements, land should be taxed uniformly
and at fair market value (Hagman & Juergensmeyer, 1986). If a beach property
transfer fee is established, it should be structured similarly to the one ill
Massachusetts, where the tax rate is a uniforin 2% for all applicable properties,
based on fair market value.

Another alternative to the flat tax rate of 2% would be a graduated tax rate
that allows a lower rate for those who are less able to afford the tax. For example,
a rate structure may be based on the sale price of a home, according to the
following schedule:

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$0- $350,000 - 0% (no taxation)
$350,000 - $500,000 - .5%
$500)000 - $1,000,000 - 1.0%
$1,000,000 - $1,500,000 - 1.5%
$1,500,000 - $2,000,000 -2.0%
$2,000,000 - $2,500,000 - 2.5%
$2,500,000 - $3,000,000 - 3.0%
$3,000,000 - $3,500,000 - 3.5%
over $3,500,000 -4.0%

It should be noted that for houses under $350,000 (the approximate median
price for a house in Honolulu) there would is no tax imposed. Whether there is a
graduated tax as shown above, or a uniform 2% transfer fee as in Massachusetts,
it is suggested that the $350,000 exemption be considered for the sake of fairness.

In order to make the transfer tax politically acceptable, the tax could be
linked with a program where landowners are eligible for reduced property
evaluations if they conduct activities which preserve or protect the beach. For
example, if a landowner has not armored the beach, or if the beach has been
stabilized but all permits are obtained, then the landowner may be eligible for 1%
to 2% reduction in their real property assessment. With the reduction in property
assessment, the current landowner would benefit from reduced county property
taxes each year. Thus, long-term beachfront homeowners would support the overall
tax package (i.e. 2% transfer fee on the sale of the property coupled with the 1%
to 2% reduction in real property assessment which is used to determine county
taxes). This arrangement would have to be worked out between the State and the
county.

To explain how the overall tax package would operate, a two million dollar
beachfront home will be used as an example. If the home were to be sold for a
price of two million dollars, the 2% transfer fee would generate a revenue of
$40,000 that could go into a proposed State Beach Fund. The money could be
used for erosion mitigation programs that benefit other beachfront homeowners and
the public. Nevertheless, a significant number of beachfront homeowners may still
object to the 2% transfer fee.

If the 2% transfer tax was coupled with a 1% to 2% reduction in property
assessments at the county level, for lots that were in compliance with all shoreline

108

regulations, then the beachfront homeowners would view the tax program more
favorably. Using the two million dollar house as an example, the overall reduction
in county property taxes can be calculated. Property tax rates for Oahu on March
3, 1992 were $3.25 per assessed value for the land, and $4.09 per assessed value
for the improvements (Honolulu Advertiser, March 3, 1992). For the sake of
discussion, it will be assumed that for the two million dollar house, one million
dollars is the assessed land value and one million dollars is theassessed value of
the improvements. A 1% reduction in the property assessment for the land would
reduce the taxes owed to the county from $3,250.00 to $3,217.50. A 1% reduction
in the property assessment for the land improvements would reduce county taxes
from $4,090.00 to $4,049.10. The total county property taxes for the 2 million
dollar beachfront home would be reduced from $7,340.00 to $7,266.60, or a total
of $73.40 ever year. A 2% reduction in the property assessment would reduce the
total property taxes by $146.80 per year. The exact percentage of property
assessment reduction given by the county could be worked out later.

The effect on county treasuries from the property tax reduction can also be
approximated. First, however, some estimates on the number of beachfront lots and
illegal structures on the island must be obtained. According to one study, along 59
miles. of surveyed beach, approximately 58%, or 34 miles were developed with
residential uses (Sea Engineering & Moon, 1991). Along a stretch of
approximately I I miles of different beaches on Oahu, there are roughly 60 lots per
mile of shoreline. About 27% of these lots are spanned by seawalls or revetments.
Of the residential seawalls and revetments on Oahu, approximately 41% are illegal
(Sea Engineering & Moon, 1991).

When the total number -of miles of beaches with residential development is
multiplied by the average number of lots per mile, an estimate of 2,040 total lots
are obtained that span the beaches of the island [(34 miles) times (60 lots/mile)].
From the estimates in the paragraph above, there are approximately 226 illegal
seawalls or revetments on the island [(2040 lots) times (27% lots with seawalls)
times (41% illegal seawalls)]. This estimated number of illegal structures is in
agreement with the approximations of the Department of Land Utilization. For this
exercise, the total number of lots eligible for the reduced property assessment is
about 1,814 properties (2020 properties - 226 with illegal structures).

The property assessment reduction, may cost the county $133,148 to
$266,295 per year in property taxes ($73.40 to $146.80 per lot per year times 1,814

109

eligible lots). This is out of a total revenue from property assessments of $423
million per year (Honolulu Advertiser, March 3, 1992). To-compensate the
counties for reduced propeM tax revenues, the State could pgy a higher fraction
of the cost of improvements within a Beach Management District. The counties
would be a major beneficiary of such improvements since healthy beaches provide
recreational opportunities for county residents. In addition, any loss in county
property taxes from the 1% to 2% reduction in property tax assessment maybe
offset by an increase in revenue if a Beach Management District increases the value
of beachfront homes.

A 1% to 2% reduction in property assessments might save the beachfront
homeowner, who is in compliance with shoreline regulations, $73.40 to $146.80 per
year. This property tax reduction, along with other beachfront management
programs that offer financial and property protection, provide significant incentive
for long-term homeowners to support the overall tax package.

The overall contributions to State revenues from the tax program could be
significant. Assuming that of the 2,040 beachfront properties on Oahu, a property
is sold on the average of once every 60 years. Using this assumption, there would
be almost 34 sales of beachfront property each year. With an assumed average
price of 2 million dollars, and a transfer fee of 2%, these sales would generate an
annual revenue of 1.36 million dollars into the State Beach Fund.

Thus, more money will be raised by the State from the transfer tax ($1.36
million dollars/year) than the County will lose by the reduction in property taxes
($133,148 to $266,295 per year). It is important for the State to administer this
money, since it will be a State agency that promotes beach district formation and
evaluates the viability of various projects. In addition, it is the State that would
pursue Federal assistance for various erosion control projects to reduce the costs
for each party.

It should be reemphasized that the discussion of tax measures to further
beach management programs is offered here not as a recommendation but as an
option that the State should investigate. Many questions remain. For example,
should the shoreline tax be imposed not only on beachfront property transfers, but
also upon the issuance of a building permit? What are the constitutional issues
related to taxing a group of homeowners along the coastline? What are the unique
political and socioeconomic conditions in Hawaii that would impede the imposition

110

of a transfer tax program similar to those in place in Massachusetts or Florida?

Any attempts to implement economic incentives and disincentives by
taxation would require additional study (see Implementation Guidelines - Chapter
XII). The discussion in this report is offered to show the reader that innovative tax
strategies, if structured properly, can have a relatively minor impact on all parties,
and can provide significant revenue for programs that benefitprivate landowners,
the public, the counties and the State.

6. Impact Fees, Easements, and Other Funding Sources. There are many
other sources of revenue for beach management programs that have not been
discussed in this report. These include the sale of easements for private structures
that encroach on State land, beach user fees, impact fees and tax deductible
contributions from the public. All of these ideas could be further investigated by
a proposed Division of State Beaches. Preliminary studies on these sources
indicate that the potential income is relatively minor compared to those sources
previously discussed in this chapter.

B. Funding a BMD - Cost Allocation

For Hawaii a shared cost system is proposed with contributions from the
State, county and landowner. One starting point in the allocation of costs may be
a scheme similar to that in Connecticut, where erosion control projects for private
properties are split equally between the State, the local government and landowners.
An allocation of costs where each party pays an equal share is easily understood
and apparently fair. However, it may be possible to structure the allocation so that
it is more politically feasible.

It is not the purpose of this study to recommend specific percentages. The
exact percentages need to be worked out later between the State and the counties.
The following should be considered in the allocation of cost for a BMD:

1. Federal - One duty of a proposed Division of State Beaches would be to
actively pursue Federal funding for erosion control projects under the River and
Harbor Act of 1962, Title I of Public Law 87-874, 76 Stat. 1173 (33 U.S.C.A. SS
426e-426g). If Federal funding is obtained, there is usually the requirement that
local funds cover half the cost of the project with the Federal government to paying
the remainder. For the following discussion, the term TOTAL COST means the

cost to design, engineer, implement and construct an erosion-control project minus
contributions from the Federal government.

2. Counly - The individual counties should be required to pay a small
amount for the improvements in a Beach Management District. A small payment
by the county should be made since the counties benefit from a beach improvement
project. In addition, the assessment provides economic incentive for the county to
adopt land-use policies that preserve State beaches.

County cooperation in many of the programs discussed in this report is
important. Therefore, the financial burden placed on the county should be
minimized. It is suggested that individual counties be made to pay no more than
20% of the TOTAL COST of a Beach Management Program. A smaller fractional
4
cost may be required to encourage county cooperation in certain programs.

For example, the property transfer tax may be controversial. Yet this tax
could provide the State with a continuous and significant source of revenue (See
example - previous section). To make the transfer tax palatable, the tax could be
linked with a county program to give a yearly 1% to 2% reduction in beachfront
property assessments for properties that are in compliance with all coastal
regulations. The overall tax package could be very attractive to the long-term
beachfront owner.

There may be mechanisms for the State to require the counties to participate
in the payment of capital improvements in a Beach Management District. In
Maryland, once there is an approved financing plan, if the county or local
government fail to pay the State its percentage of the cost, - then the State
Comptroller may withhold from State-collected, locally shared taxes; or from
certain State grant programs; or from the State aid for police protection, a sum
sufficient to reimburse the State for any amount that remains unpaid by the
.counties (Md. Nat. Res. Code Ann. S 8-1103). In Hawaii, a mechanism that
requires the participation of the counties would need further investigation. While
required participation may be valid for improvements within a BMD, required
participation in other programs may be another matter. For example, the 1-2%
reduction in property assessments discussed in this report is within the discretion
of the counties. The Constitution of the State of Hawaii originally reserved to the
State the duties of real property taxation, however, this has been amended so that
the power is exercised exclusively by the counties (HRS-S 246A-1).

112

The counties may object if beachfront homeowners received a reduced
property assessment for compliance with shoreline regulations since this would
reduce tax revenues. As compensation to the counties, the State could agree to pay
a higher portion of the costs for the capital improvements within a Beach
Management District. For example, an allocation scheme may require that the
counties pay only 10% of the cost of the improvements versus 20%. In return, the
county would agree to provide a 1% to 2% reduction in property tax assessments
to beachfront property owners, if they are in compliance with all regulations.

County funding may be provided by a capital projects fund, the general
fund, or the issuance of general obligation bonds or improvement district bonds.
Many States that have established BMI)s have provisions that allow bonds to be
issued to raise funds for the State or local share of the district.

3. Coastal Landowner - Coastal landowners receive specific benefits from
a beach improvement project. One benefit would be an increase in property values,
derived from the presence of a healthy beach that provides recreational
opportunities and improved aesthetics, as compared to a shoreline with no beach
that has been stabilized by a seawall. The major specific benefit would be the
increased protection against wave energy that is given to their property by the
improvement. This benefit should not be discounted. If sea-level continues to rise
at the present rate, or the rise accelerates as most researchers predict, then the need
for additional coastal protection to protect private property from greater levels of
erosion would grow.

Since beachfront landowners receive specific benefits from the improvement
district, they should be assessed a fair amount. Nevertheless, they should not be
assessed so much that there is no economic incentive to join the BMD. If the
majority of the landowners cannot cooperate, then a District may not be formed,
and no one would benefit.

it is suggested that the landowner assessment be structured so that the
fractional cost of paying for a project of surgebreakers' or sand replenishment be

Surgebreakers have been used to halt erosion at Kualoa Beach Park. One
advantage of surgebreakers is the low cost compared to a detached breakwater.
Such structures may transfer the erosion problem by interfering with longshore sand
transport. Surgebreakers for residential use would require additional study.

113

less than paying the full costs of a revetment. Thus, economic incentive is created
for the landowner to select options that preserve the beach and protect private
property.

The exact percentage of the landowner's assessment could be worked out by
a proposed Division of Beaches. An initial suggestion is that the landowner
assessment range between 30%-45% of the TOTAL COST of the project. The
exact amount would depend on several factors, including the type of improvement
project, the total costs, and the degree of public benefit. If the pubic benefit from
the project is great, then the landowner may be required to pay a smaller
assessment (e.g., 30% in the discussed allocation scheme). If the public benefit is
small, then the landowners would pay a larger fraction of the TOTAL COST and
the State's contribution would be reduced.

4. State - Whatever costs of a BMD are not paid by the Federal government,
the landowner, or the counties would need to be paid by the State. Assuming that
the counties were to pay 10% of the TOTAL COST of the project, then the
contribution from the State may range between 45%-60%. The contributions would
be paid from a State Beach Fund. Revenues into the Fund would be derived from
legislative appropriations, the issuance of bonds, federal contributions -where
applicable, and a tax on beachfront property transfers.

C. State Beach Fund

Many coastal states have established dedicated State funds to support beach
preservation activities. For example, Delaware has established a Beach
Preservation Fund that is to have a minimum balance of one million dollars at the
start of each fiscal year (Del. Code Ann. tit. 7, S 6808). The Fund is to be used
to finance activities that enhance and preserve public and private beaches and
mitigate beach erosion.

Two- separate beach funds are established in Florida. The Beach
Management Trust Fund receives monies from State appropriations and from
permitting fees (Fla. Stat. Ann. S 161.0535, S 161.091). Disbursements from the
Fund may be made by the Division of Beaches and Shores to carry out the State's
responsibilities according to a comprehensive, long-range, management plan. The

114

plan deals with erosion control, beach preservation, beach restoration, beach
renourishment, dune construction and coastal studies. In additioril Florida has
established an Erosion Control Trust Fund with revenues to the Fund derived from
fines and awards of damages for regulatory violations (Fla. Stat. Ann. S 161.054).

In Maine, the State owns less than 3% of the coastline, which is the lowest
percentage of publicly owned shoreline in any coastal State in the United States.
To deal with the problem of limited public access, the State has established a
Shoreline Public Access Protection Fund to support the acquisition and
development of shoreland areas for public use.

In Louisiana, there is the Coastal Resources Trust Fund where capital is
derived from State appropriation and surplus funds from other accounts. The
money is used for the State's coastal resource programs (La. Rev. Stat. Ann. S
49:213.22, 49:214.40).

For Maryland, an Ocean Beach Replenishment Fund is established with
monies from State appropriations, bonds, and local contributions ((Md. Nat. Res.
Code Ann. S 8-1003). The Fund is maintained -for bulkhead construction, dune
restoration, beach replenishment, and land acquisition. Monies from the Fund may
not revert to the General Fund of the State. For land acquisition, the State pays
100% of the cost from the Fund. For all other activities the State contribution is
limited to 50% of the total cost.

Federal programs that provide financial assistance for beach erosion control
projects require that the costs be shared with either the State, municipality, or other
political subdivision in which the project is located (33 U.S.C.A. 426e). North
Carolina has established the Beach Erosion Control Project Revolving Fund that
consists of monies from State appropriations and other sources. The Fund is used
to finance the local portion of the nonfederal share of the cost of beach erosion
control projects (N. C. St. S 143-215.62).

Similarly, Virginia has established a State fund to help local governments
pay for half of the nonfederal costs of erosion abatement projects. Unexpended
monies go into the Special Emergency Assistance Fund, which is used, in part, to
restore beaches destroyed by storms or hurricanes.

From the above examples, dedicated State beach funds have been used to

115

buy coastal land, develop access routes, support coastal research, education and
management programs, finance erosion control capital improvements, and provide
.emergency assistance. For Hawaii, it is suggested that a dedicated fimd be
established to further . beach preservation activities. A Hawaii State Beach Fund
should be established to capitalize BMD projects, acquire selected coastal
properties, pay for renourishment projects, and fund coastal and engineering studies
benefitting the State and landowners. Money for the Fund would be derived ' from
State appropriations, Federal contributions where applicable, local contributions,
6
and the shoreline property transfer tax.

The need for a dedicated beach fund is clear. Certain erosion control
measures may fail without proper maintenance. For example, the long-term
effectiveness of a sand replenishment project may deteriorate without periodic sand
renourishment. Without a dedicated source of funding, any financial contributions
the State would make with regard to scheduled maintenance could be postponed
because of other priorities. This could leave coastal landowners without adequate
protection of their properties.

Another reason for a dedicated ftmd is that many beaches will need to be
monitored on a periodic basis. Monitoring is required for two purposes. First,
the stability of a beach fill should be checked to improve our poor understanding
and prediction capability of erosion processes, and help track erosion on a statewide
level. Second, monitoring is needed to search for dangerous unnatural conditions
that may expose the State to liability for failed erosion control structures.
Monitoring activities must be continuous and cannot be subject to the whims of the
political process.

Finally, a dedicated State Beach Fund allows financial reserves to be built
up for the inevitable storm or hurricane that will hit the islands. After a storm
event, opportunities may exist to provide financial assistance to the landowners and
recover the eroded beach. A dedicated Beach Fund would facilitate the
accumulation of the necessary financial reserves.

6 For landowner assessments within an improvement district, a separate fund
may be needed so that monies are not commingled. There is the legal requirement
that assessments for improvements must stay within the district.

116

VIII. REGULATORY OPTIONS

A
Since the formation of an beach improvement district may not be feasible
for every shoreline in the State, other beachfront management options are discussed
that may lead to increased beach preservation. The three options include the
development of a voluntary relocation program, modifications of the State shoreline
setback and strategies for improved enforcement of existing shoreline regulations.
As with all options developed in this report, considerable attention is given to the
concerns of the private property owner.

A. National Flood Insurance - Upton-Jones Amendment

Before 1988, the National Flood Insurance Program paid insurance benefits
only to those insured buildings that had sustained physical damage as a result of
flooding or flood-related erosion. Beginning in 1988, the Upton-Jones Amendment
to the National Flood Insurance Program authorized advance payments of insurance
benefits if a landowner's home is threatened by erosion and the landowner
demolishes or relocates the structure (Section 544, Housing and Community
Development Act of 1987). Under Upton-Jones, payments for demolition before
collapse are I 10 percent of the value of the structure. Of this payment, 10 percent
is to cover the cost of demolition. If a structure is relocated instead of demolished,
payment would be the actual cost of relocation, up to 40 percent of the value of the
structure.

Value of the structure, as determined by the amendment, is the lower of 1)
the value of a comp arable structure that is not subject to imminent collapse; 2) the
id f improvemen
price pal or the structure and any i ts to the structure; or 3) the value
of the structure under the insurance contract.

To qualify for erosion benefits, the homeowner must be covered by Federal
Flood Insurance on or before June 1,1988. In addition, the homeowner must have
the insurance at least two years before certification that the structure is in a zone
of imminent collapse. The statutory period may be reduced if home ownership is
less than two years.

In determining the zone of imminent collapse, the Federal Emergency
Management Agency has adopted interim criteria. Presently, the zone is defined
as the area seaward of a line that is 10 feet plus five times the local average annual

117

erosion recession rate as measured by the vegetation line, a dune line or the high
tide line. For structures that fall outside this zone, FEMA will consider any
technical or scientific data that demonstrates a unique or highly unstable condition
at the site (National Research Council, 1990). Erosion benefits may be available
even for those properties that have been stabilized by seawalls (Michael Buckley,
pers. comm., Federal Emergency Management Agency). For stabilized shorelines,
such factors as the design of the structure, the amount of maintenance, local
geomorphic features, and historical and spatial changes in the beach system may
be considered to determine a zone of imminent collapse.

Under Upton-Jones, individual States and local governments may certify that
a structure is in a zone of imminent collapse if they adopt a statewide coastal zone
setback program that is based, in part, on a multiple of the local shoreline recession
rate. Several States, such as North Carolina, Michigan, South Carolina, and
Pennsylvania, have already qualified to make certifications (National Research
Council, 1990). Other coastal States are developing their program. For example,
in Texas, it is the General Land Office that acts as the lead agency for the
coordination of coastal erosion avoidance and planning (Tex. Nat. Res. Code S
33.601). The Commissioner of the General Land Office is authorized to perform
all acts necessary to develop and implement a program of certification of structures
subject to imminent collapse due to erosion.

If a beachfront home is constantly threatened by erosion, or in a zone of
imminent collapse, the landowner may welcome the option of receiving advanced
insurance payments to relocate or demolish the structure. The economic incentive
to landowners could be made even greater if Upton-Jones'insurance payments to
demolish the building were combined with a - State program to purchase the
underlying land. For minimum economic loss, landowners would benefit if they
avoid a situation where waves are regularly threatening private property. The
public would also benefit. In many instances, it may be possible to recover lost
beaches simply by moving erosion control structures inland.

A proposed Division of Beaches could work to develop and implement a
State certification program where landowners benefit from erosion payments under
the Upton-Jones Amendment. In addition, the Division could develop a program
where payments from the State Beach Fund are used to provide additional
economic incentive to move off selected beach areas.

118

B. Zoning

Once development occurs near an unstable shoreline, protection of the
structures and preservation of the beach become considerably more costly and
ed by the numerous suggestions in this report to
complex. This is exemplifi
establish and fund a Beach Management District System for the State. In addition,
halting a receding shoreline with protective structures may benefit only a few and
seriously degrade the natural beach and the value it holds for the majority.
Therefore, it is recommended that land use policies along the coastline be
reevaluated to address the continued loss of beaches and the future problems
associated with sea-level rise.

It is vital that shoreline instability be anticipated at the earliest stages of
zoning. In many areas, proper planning may be the only way to achieve the dual
objective of beac h preservation and protection of property rights. This study
proposes a new setback line for large tracts of undeveloped land. The shoreline
setback would apply to new developments that require the subdivision of land or
are located in a non-urban district. These new setbacks need not apply to rocky
shorelines since these coastal sectors are considerably more stable than the beach
areas. Nevertheless, it maybe decided to apply the new setback to all shorelines
to protect scenic or open space resources, or to simplify administration of the
setback law.

It is proposed that the shoreline setback for sand beaches be the greater of

1) 60 feet fTom the natural vegetation line; or

2) 30 times the annual average erosion rate of the natural vegetation line;
or

3) the historic range in the position of the unstabilized vegetation line over
a minimum of 30 years.

Reduction of the setback should be granted if it is necessary to maintain
buildable area. If a new setback reduces the buildable area by 50% or more, an
exception could be made to allow a smaller setback. This exception is analogous
to the setback provisions for small lots at the county level. On Oahu, Kauai and
Hawaii, if a 40 foot setback reduces the buildable area by 50%, a 20 foot setback

119

is allowed. The 50% provision could also apply to new subdivisions and newly
reclassified urban land.

There are many ways to structure the setback reduction. Either, the setback
could be halved, as for small lots on Oahu, Kauai, and Hawaii. Alternatively, the
setback could be reduced until a 50% buildable area is achieved. The later
alternative would provide more protection to the beach resources of the State. The
exact reduction strategy would need further investigation.

For each parcel of land, the setback reduction may apply only one time.
This prevents the practice of numerous subdivisions to obtain multiple reductions
with smaller and smaller setbacks.

The setback as proposed has the following features:

1) In the future, the eligibility of the State to obtain Federal assistance for
erosion control projects may be dependent on the State adopting a setback with a
30-year annual average erosion rate. Presently, the State is eligible for Federal
funding and assistance from the Secretary of the Army for small shore and beach
restoration and protection projects (33 USCA S 426g). Federal funds of up to
$2,000,000 can be allotted for shore erosion mitigation projects that benefit both
the public and the private landowners, provided the State or local government share
in the cost of the project. This funding could help offset the State and county cost
of improvements within a Beach Management District. Congress is to consider the
elimination of Federal assistance unless the State adopts a beach front management
program that includes restrictions on new development seaward of a setback based
on a 30-year annual average erosion rate (33 USCA S 426e).

2) The use of an annual average erosion rate allows the State to certify for
approval those homes that may benefit under the Upton-Jones amendment to the
National Flood Insurance Act of 1968 (44 CFR Part 63). Money from the Upton-
Jones program for relocation or demolition, can be coupled with funding from the
State to develop a voluntary program to move structures inland. This program
should be viewed favorably by coastal landowners since it provides additional
financial protection against coastal erosion, sea-level rise, and storm events. In
addition, the removal or relocation of certain erosion control structures inland may
allow the recovery of a lost beach.

120

3) The 30-year erosion setback proposed in this study is consistent with
provisions in the Upton-Jones amendment. Specifically, the amendment states that
future flood insurance coverage and certain types of ederal disaster assistance will
be available only for buildings that are constructed or relocated inland of a 30-year
construction setback (Public Law 100-242-Feb.5, 1988). While the Upton-Jones
amendment applies to relocation benefits for pre-existing structures, the setback rule
discussed in this report would apply to new structures. It is inconsistent to have
a 30-year erosion setback for the relocation of existing structures and the 20-40
foot Setback now in effect in Hawaii for new structures (HRS-205A-41).

4) The setback reduction to preserve buildable area prevents the situation
where high erosion rates or extremely unstable shorelines result in the elimination
of the use of the land. By preserving buildable area and maintaining "economically
viable use of the land," the success of a takings challenge, even after the Lucas
case (Chapter 111), is greatly diminished. While the takings issue may still be
raised by landowners, the merit of their claim is significantly reduced. It is one
strategy of this report to address the concerns of the public and the private
landowner. Therefore zoning strategies are formulated to stay clear of the
regulatory takings problem. This is especially critical given the recent decision
by the U.S. Supreme Court in Lucas.

5) Besides the preservation of buildable area, additional constitutional
protection is provided by the proposed setback. As discussed in Chapter 111, a
regulation may be held invalid if it "does not substantially advance legitimate state
interest" or "denies an owner economically viable use" of the land (Agins v.
Tiburon, 447 U. S. 255, 100 S. Ct. 2138, 65 L. Ed. 2d 106 (1980). In determining
if the regulation "substantially advances legitimate state interest," the courts will
consider, among other factors, (a) if there is a legitimate state interest and (b) if the
regulation is overly broad or more restrictive than necessary to achieve the state
interest.

The legitimate state interest of the setback proposed in this study is the
protection of public access and the prevention of serious harm to public trust lands
(see, Figs. 2 through 5). In addition, the proposed setback is no more restrictive
than needed to advance the se legitimate government interests. For example, if the
shoreline is stable or accreting, the setback would be, at the most, 60 feet. Contrast
the 60-foot setback with the proposal in House Bill 893 (1991 legislative session)
which required a 150-foot setback for all non-urban land according to the State

121

land use classification scheme. Landowners could claim the 150 foot setback as
being overly broad, if their shoreline was relatively stable or subject to accretion.
However, the State could counter that the 150 foot setback has objectives other
than beach preservation, such as the protection of scenic and open space resources.

. 6) For relatively stable or accreting shorelines, the setback of 60 feet is not
unduly burdensome. Landowners would appreciate the 60-foot setback over the
150-foot setback proposed for non-urban land in House Bill 893 (1991 legislative
session). The City and County of Honolulu has recently adopted a 60-foot setback
for all new subdivisions. The need to extend the setback a minimum of 60 feet
from the old distance of 40 feet is exemplified by the numerous beaches that have
been lost even though they are relatively stable (e.g., Kahala - Fig. 3). The
increased setback of 60 foot setback would further advance the CZM objectives of
scenic and open space resource preservation and coastal ecosystem protection.

7) The proposed setback will help protect the beach resource. For the few
beach sectors that are chronically eroding (similar to Iroquois Point - Fig. 2) or
highly unstable (similar to the southeast end of Lanikai Beach - Fig. 5) the
proposed setback would offer more protection than the 60-foot or, if needed, the
150-foot. setback. By allowing the beach to migrate naturally, the need for
hardening of the shoreline can be reduced or eliminated, and the pubic trust
resource can be preserved for future generations (Fig. 22).

In those instances where the shoreline setback is greater than 60 feet, a
program should be instigated where the landowner can be given variances for
increased height, greater density, or a reduced fTont and side setback for land
adjacent to the beach. By the use of compensating variances, it may be possible
to maintain a significant amount of buildable area even with a greater shoreline
setback. Under ideal conditions, the landowner could have the best of both worlds
(i.e., the same amount of buildable area as before the expanded shoreline setback
and a healthy beach/dune buffer system that protects the property from wave
attack). If packages of variances were offered to those landowners who would
have setbacks greater than 60 feet, the use of an overlay district to define areas
subject to different land use controls may be ideal (Robin Foster, pers. comm.,
Lacayo Planning Inc.). Alternatively, a new zoning designation at the State or
County level could define appropriate construction and land use guidelines so that
buildable area is maintained while the beach is preserved.

122

Economic burden on the landowner can also be alleviated by developing
a program of Transferable Development Rights (TDR!s). The theory behind TDR's
is that they allow the owner of the right to build more of something on a
designated parcel of land than the normal development regulations would allow.
TDR's can be used by the beachfront landowner on other inland property they may
own. If no other property is owned, the impacted landowner may sell the right to
another inland landowner. Thus, TDR!s can be used as a form of compensation for
those landowners that are impacted by an increased shoreline setback. Setting up
a system that transfers development rights from the restricted area (sending area)
to land on which the TDR can be used (receiving area) can be extremely complex
(Hagman & Juergensmeyer, 1986). The use of a system of TDR's would require
additional study.

To further reduce the economic burden on the landowner, the shoreline
setback may be reduced if a beach replenishment project designed to preserve the
beach has been funded and permitted before development begins on the site. Other
States have provisions in their setback laws that allow for reduced setbacks for
established replenishment projects (Fla. Stat. Ann. S 161.053 (6)(d); S. C. Code
Ann. S 48-39-280). The landowner would be able to work with the proposed
Division of State Beaches to receive technical assistance on the types of sand
replenishment projects that may be useful in reducing the proposed setback. In
addition, the proposed Division of State Beaches could investigate the possibility
of providing a fraction of the cost of the erosion control project, if the landowners
project would benefit the public.

In sum, the State and county should make the greatest effort to coordinate
land use policy so that beaches can be preserved while the landowner is
compensated. Most promising appears to be a program of compensating variances,
Transferable Development Rights and reduced setbacks for preapproved and
prefinanced sand replenishment projects.

Increasing the shoreline setback raises the issue of what effect this increase
will have on existing legal residences. The concern of a coastal homeowner could
be that if a home becomes nonconforming and restrictions are placed on the
reconstruction of a house should it be destroyed, then the homeowner may not be
able to finance, refinance or insure the house. To protect the homeowner, it is
suggested that there be provisions in the proposed setback ordinance that allow
reconstruction of a home, in the case of damage, as long as the new residence is

123

not enlarged or placed ftirther seaward. If a building is destroyed by an act of
God, it may be held that a nonconforming structure can be rebuilt. (Hagman &
Juergensmeyer, 1986).

The wisdom of allowing a home destroyed by storm waves or erosion to be
rebuilt may be questioned. Nevertheless, this report attempts to address the
concerns of the private property owner. Rather than moving existing landowners
inland by prohibiting the repair of nonconforming homes, a strategy of coastal
retreat could be provided through a voluntary program that offers economic
incentives for coastal landowners (section A of this Chapter). Another economic
incentive, as it pertains to damaged nonconforming houses, is to grant an allowance
or credit to reconstruct a larger house, if the most seaward portion of the new
house is moved inland. A formula that relates the allowed size increase of the
house with the distance moved inland could be worked up by the appropriate
county authonities.

Regarding the implementation of the proposed shoreline setback ordinance,
it would be the applicant or landowner who would fund a coastal study to
determine the appropriate setback. Previous aerial photographic and historical
studies would be allowed as a substitute for thecoastal study, where suitable data
and analysis exist for the beach segment in question. Placing the burden on the
coastal landowner to conduct the erosion study would relieve the State of the
financial burden of analyzing all the State's shorelines. To ensure technical
accuracy, the State could have in house staff with technical backgrounds to review
the scope, methods and accuracy of the erosion studies. It should be noted that
many environmental regulations require the applicant of the activity, not the
government agency, to conduct appropriate scientific studies (e.g., EIS under the
National Environmental Policy Act, or monitoring for a storm water permit under
the Clean Water Act).

In the Kauai County Zoning Ordinance (SEC. 8-13.1), there is a designation
of Shore Districts. One requirement is that the applicant for a permit to build
within the Shore District must provide an information report. The report describes
the rate of Shore District Change over time under both natural and proposed
artificial conditions. The Shore District designation in'Kaual is a type of overlay
district (see Chapter V). The requirement of an information report in Kauai's
Zoning Ordinance is analogous to the proposal in this report that all new beachfront
subdivisions or developments on nonurban land conduct a coastal erosion study that

124

determines the shoreline setback according to the proposed setback rule.

It could be a proposed Division of Beaches that would adopt the rules,
procedures and technical requirements on how the average annual erosion rate and
the historical range in the position of the vegetation line are determined for each
beach sector. The Division can monitor data on sea-level rise, and if appropriate,
factor the local data into the calculations. Where the shoreline has been altered
artificially, the Division could develop guidelines for the establishment of a setback
using other criteria, such as the historical changes on adjacent property, or on the
mean high water line. All rules that the Division adopts should insure proper legal
procedures, fairness and objectivity.

C. Enforcement

Many of the problems along the coast are due to lack'. of enforcement of
existing laws. Significant improvement in the management of beaches could be
made if existing laws were enforced. During Coastal Zone Management public
workshops in 1990, it was noted that there were significant instances of non-
compliance and illegal, non-permitted uses and developments. In one CZM study,
it was noted that along a stretch of Lanikai Beach consisting of 36 lots, there were
22 illegal seawalls and 9 non-conforming walls. Only two of the seawalls had the
appropriate permits (Edward K. Noda and Associates Inc., 1989). In another study
of selected beach sites on Oahu, approximately 41% of the structures along the
shoreline were illegal (Sea Engineering & Moon, 1991).

As with the enforcement of other environmental regulations in the State,
there is a constant shortage of staff and funding to monitor and enforce coastal
regulations. As a result, many illegal activities go unnoticed., For those illegal
activities that are discovered, there is the problem of no effort to follow through
with enforcement a .ction. Other coastal states have addressed this problem by
_41 establishing dedicated funds specifically for enforcement. For example, in Florida,
the Erosion Control Trust Fund is established with monies from fines or awards of
damage for regulatory violations (Fla. Stat. Ann. S 161.054).

It is suggested that Hawaii establish a dedicated Beach Enforcement Fund.
An initial legislative appropriation could be made into the Fund. Money in the
Fund would be used specifically for beach enforcement activities, including the
hiring of personnel, monitoring of the shoreline, citation of violators, and court

125

action if necessary. Any fines collected for violations of the setback law or the
SMA, or any damage awards would go into the Beach Enforcement Fund for future
enforcement activities. Thus, the ftmd may, but need not be, self perpetuating.

Nevertheless, there is more to the problem of enforcement than just a lack
of money to hire enforcement personnel and county corporation counsel. With
regard to illegal seawalls and revetments, enforcement action is hampered by
opposing factors. For example, enforcement action should be uniform. While
agencies are given discretion in the enforcement of rules, they cannot patently
abuse that discretion. The need for consistent enforcement is difficult when some
homeowners may be in dire need of the protection offered by illegal seawalls and
revetments to protect their property. Stiff penalties to remove illegal structures
could be viewed by government agencies as harsh or draconian. Variances for
hardship could be granted, but to date few counties have any policy that defines
true hardship. Therefore, there is a tendency to grant a hardship variance whenever
property is threatened by erosion. Another alternative is to use the Beach
Enforcement Fund to develop a program of fines and subsidies.

The Beach Enforcement Fund could provide a new way in which
enforcement action is viewed and undertaken. For illegal seawalls and revetments,
a carrot and stick approach could be developed. The stick would be in the form
of fines, to encourage landowners to obtain the proper permits or remove the illegal
structures. For the case where houses are so close to the shoreline that removal of
a seawall would expose the residence to wave action, then low-level fines, rather
than hardship variances should be considered. The amount of the low-level fine
would be at the discretion of the administering agency, but some degree of
uniformity in setting the fines should be achieved. For example, if the house is
less than 10 feet from the seawall, a fine of $ 1,000 to $2,000 dollars per year could
be imposed, rather than granting a hardship variance. Revenues from low-level
fines can be placed in the Beach Enforcement Fund. Money from the Fund can
then be used to provide subsidies to help landowners convert illegal and legal
vertical seawalls to bun'ed erosion control structures. For many areas, the
movement of vertical walls and other steep structures awqy from the tidal zone
could lead to the temporaly recove!y of a lost beach.

Thus, the Beach Enforcement Fund provides a needed degree of flexibility.
For unavoidable actions that affect the beach, low-level fines can provide financial
support for programs that restore or preserve beaches at other locations. For

126

flagrant violations of the shoreline setback or SMA law, the fines can be increased
to provide ample deterrence, financial support for enforcement activities and
subsidies for the seawall conversion program. In setting fines, factors that may be
considered include, but are not limited to: i) the distance of the residence from the
shoreline; ii) the need for the structure after considering historical erosion patterns
and oceanographic wave characteristics; iii) the potential impact of the illegal
activity on the adjacent shoreline; and iv) past dealings with the administrative
agency.

. The Beach Enforcement Fund should be viewed favorably by a majority o
beachfront homeowners on the island. Approximately 90% of the beachfront
homeowners are in compliance with the law (See Chapter 7 on taxes; an estimated
27% of the beachfront lots on Oahu have seawalls or revetments; about 41% are
illegal). As long as a homeowner is in compliance with the law, there would be
no threat of fines. In addition, the homeowner may be eligible for subsidies to
build buried erosion control structures, should their property be threatened by

erosion.

Beach enforcement funds could be established at the State or county level,
depending on the government agency that takes the lead in beach enforcement
activities. The advantage of enforcement at the county level is that the counties are
currently conducting enforcement activities for illegal structures. Therefore, State
enforcement proceedings may detract or duplicate county activities. The
disadvantage of county enforcement is that individual county concerns may be
given precedence over preservation of the State's beaches. One workable solution
would be to have the counties continue their enforcement work with some
monitoring by a State agency. The Office of State Planning, as lead agency for the
Coastal Zone Management Program, has the duty to monitor the activities of State
and county agencies to ensure that they adhere to the CZM objective and policies.
It is suggested that a new objective and policy be added to HRS-205A-2 that
specifically addresses the problem of beach loss and the preservation of sandy
shorelines.

127

IX. DIVISION OF STATE BEACHES

Numerous coastal states have established offices of beaches whose function
is to administer beach management programs. For instance, in Delaware, the
authority to enhance, preserve and protect public and private beaches is vested
solely in the State Department of Natural Resources and Environmental Control.
The Department can construct and maintain groins, jetties, bulkheads, dunes,
breakwaters and other facilities along any public beach or shoreline area in the
State (7 Del. C. S 6803). In Florida, there is the Division of Beaches and Shores
within the Department of Natural Resources that develops, maintains and
administers the comprehensive long-term Beach Management Plan for the State
(Fla. Stat. Ann. S 161.161). In Rhode Island, it is the Department of
Environmental Management that has the authority to devise and implement
economical and effective methods for preventing beach erosion (R. I. Gen. Laws
S 46-3-4).

Coastal studies in Hawaii have recommended the formation of an "Office of
Beaches" (see, e.g., Oceanit, 1990). In 1991, House Bill 219 was to establish an
Office of Beaches within the Department of Land and Natural Resources. Its
purpose was to advocate protection, improvement, and creation of beaches, manage
beach resources, and initiate public beach widening and regional beach stabilization
projects. The Office would have facilitated the formation of beach districts and the
use of sand replenishment. The Bill passed through the Water, Land Use and
Hawaiian Affairs Committee, and through two readings in the House. However,
the Bill died in the House Finance Committee.

As discussed in Chapter V, the formation of a Beach Management District
requires active coordination and participation by a government agency. Efforts by
other coastal States to form a Beach Management District without an active
government role have been futile.

It is recommended that an agency be established within the State to
administer a Beachfront Management Program, and actively promote, coordinate,
and administer the formation of BMDs. The new agency could be set up as an
Office, a Branch of a Division, or a Division of a Department. Alternatively, the
Coastal Zone Management Program, or a unit within the Department of Land and
Natural Resources could be expanded and given new duties. It is not the purpose
of this report to recommend the exact structure of the entity. Further study would

128

be required (see Implementation Guidelines - Chapter XII). For the sole purpose
of discussion, it is assumed that a Division of Beaches is formed. The reader
should be aware that although the entily is referred to as a Division of Beaches,
this is not a recommendation on its structure, organization or association.

Assuming a Division of State Beaches is adopted, the new Division would
be required to develop and administer many of the programs proposed in this
report. The Division of Beaches would have numerous duties, including the
following:

1) Pursue Federal Funding. There are two federal programs from which the
Division should actively seek assistance. Under the Upton-Jones amendment of the
National Flood Insurance Act, benefit payments from flood insurance coverage may
be provided for certain homeowners threatened by erosion. If Hawaii were to
qualify for such a program, the Division of Beaches could play an active role in
helping landowners take advantage of this program. The Division could also
pursue federal assistance under the River and Harbors Act to pay for small erosion
control projects that benefit the public and private sectors (33 USCA S 426e-426g).
Payments under this program could be used to help finance the capital
improvements in a Beach Management District.

2) Voluntary Relocation Program. The Division could develop a voluntary
relocation program whereby payments under the Upton-Jones amendment of the
National Flood Insurance Act are combined with money from the State Beach Fund
to provide homeowners an economic incentive to demolish or move their homes
off erosion-prone beaches.

3) Government Coordination. The Division would coordinate activities with
federal, State and county agencies to mitigate erosion and manage the shoreline.
Cooperation would be critical in the areas of funding and establishing Beach
Management Districts.

4) Shoreline Setback Regulation. If a shoreline setback rule was adopted as
proposed in Chapter VIII, the new Division would need to develop rules regarding
the technical requirements for determining the average annual erosion rate and the
historical range in the position of the vegetation line. The rules should cover
minimum technical standards as well as procedural matters that ensure proper due
process to the applicant. The shoreline setback would apply to new development

129

on land that has not been subdivided or zoned for urban use. The Division could
work with landowners to determine the appropriate setback, either through previous
studies or with the help of the landowner's consultants.

5) Beach Fund Administration. The Division would establish guidelines for the
collection, expenditure and accounting of monies in the State Beach Fund. The
Division would also investigate the possibility of providing no-interest loans from
the- Fund to homeowners for shoreline preservation projects.

6) Legislative Funding. Specific requests for legislative appropriation may be
necessary to maintain the State Beach Funds and to finance certain preservation
projects. The Division would prepare such requests.

7) Permitting Assistance. The Division would work with the counties and
landowners in permitting erosion-control options along the shore. For projects that
require buried erosion control structures, the Division would ensure compliance
with the National Historic Preservation Act and the State's historic preservation law
(HRS - 6E). For projects that require activities on the beach or offshore, the
Division would become the lead-agency in permitting. Where technical data is
required that is not site specific, the Division could provide such inforination.

Where it is possible to consolidate and coordinate effort among permits,
hearings, and applications for variances, the Division would strive to do so by
interagency agreements. These agreements would be similar to those now in effect
between the Department of Land and Natural Resources and the Department of
Transportation. The Department of Land and Natural Resources has established a
process to get all government agencies involved during @'Ile issuance of their
conservation district permits (Roger Evans, pers. comm., DLINR). Nevertheless, up
to six permits may still be required by Federal and State law. The Division of
State Beaches could help the applicant by developing, for each specific erosion
control measure, a master application form which contains sufficient information
for all affected agencies.. Copies of the completed application could then be sent
to all affected agencies for fiirther evaluation. Such a strategy could significantly
reduce the permitting time and costs for landowners. Through these streamlining
measures, a new government agency and more regulation may not necessarily mean
more bureaucracy for the landowner. Nevertheless, the goal of one window
permitting is probably unlikely, since some of the governinent agencies have their
own specific requirements. For example, the Department of Health Water Quality

130

Certification Permit under Section 401 of the Clean Water Act may require
monitoring of the water before, during or after a proposed activity. This
requirement is unique to the DOH, and requires the applicant to coordinate the
monitoring with the Department.

8) Technical Assistance. Technical assistance on beach replenishment and other
erosion mitigation options needs to be provided to property owners and the
counties. The Division would provide such assistance either by in-house staff, or
with the use of a consultants.

9) Erosion Control Mitigation Design. The Division would actively explore all
practical and economic methods to control shore erosion. The Division would
design, or cause to be designed through outside help, specifications on erosion
control structures for homeowners, which are suitable under a defined range of
coastal parameters.

10) Disaster Plan. A disaster plan could be developed which would allow State
acquisition of coastal properties from those who wish to sell after a major storm,
tsunami, or hurricane. The plan would also -develop post-storm emergency
measures to assist the counties and coastal landowners. This plan would have to
be coordinated with the emergency plans of the State Civil Defense Agency.

11) Rulemaking. The Division would establish rules and criteria to place priorities
on:

a) those shorelines which can-be effectively replenished with sand;

b) those shoreline sectors which would benefit fi7om the formation of
Beach Management Districts;

c) those shoreline sectors which should be acquired;

12) Scientific and Technological Research. The Division would help to coordinate
and initiate research related to the following:

a) a statewide inventory of onshore and offshore sand resources, including
economic and engineering feasibility studies of resource use.

131

b) a study of natural and human processes that have an impact on Hawaiian
beaches, such as storm frequency and coastal development trends.

c) a long-term monitoring program of the State's shorelines in high-
resolution, repetitive field surveys and historical shoreline analyses.

d) the tracking of research concerning global sea-level rise, and the
continued analysis and monitoring of local sea-level rise.

13) Public Education. The Division would develop a program to educate the public
on various aspects of shoreline erosion, coastal hazards and sea-level rise.

14) Sand Replenishment. The Division should investigate the feasibility of a State
beach renourishment program that operates all year on all the islands. Such a
program would reduce the cost per cubic yard to renourish beaches. This program
has been suggested by other coastal studies (Oceanit, 1990). .

15) Administration. The Division would develop, implement and administer a
comprehensive long-range beach management plan for the State of Hawaii.

132

X. CASE STUDIES

One goal of this study was to develop a menu of beach management options
of which one or more of the alternatives could apply for every mile of the
shoreline. In order to test the ideas in this report, Kahala Beach and Ewa Beach
have been chosen for case studies. These sites represent a wide range of
socioeconomic conditions. At Kahala, an attempt will be made to apply the
improvement district concept to test the feasibility of a sand replenishment project.
At Ewa Beach, the overlay district concept will be applied to test new programs
that the county may wish to implement. In order to show how the programs
discussed in this report would work, it is assumed that a Division of Beaches has
been formed.

A. Ewa Beach

1. Location. Ewa Beach is located to the west of the entrance to Pearl
Harbor (Fig. 35). The area of interest is bounded by Ewa Beach Park on the east
and the rocky coastline near Muumuu Place to the west. This rocky coastline
marks the western end of the littoral cell (Fig. 36). The area of interest spans a
length of approximately 1.5 miles, The beachfront lots discussed in this section
are covered by tax map keys 9-1-28, 9-1-25; 9-1-7; 9-1-6; 9-1-24; 9-1-23 and 9-1-
5.
2. Zonin . The area of interest is designated as Urban on the State Land Use
Commission Maps (Fig. 37). On the Oahu Development Plan, the area has been
zoned for residential use (Fig. 38). Specifically, the residential areas are zoned R-5
(Fig. 39). According to the Oahu Land-Use Ordinance, R-5 zoning has a minimum
lot area of 5,000 sq. ft. and a minimum lot width of 50 feet. The area is also
designated on the National Flood Insurance maps as AE and VE zones (Fig. 40).
The west end of Ewa Beach is in the AE zone, which indicates the area is subject
to coastal flooding. The east end of Ewa Beach is in the VE, zone which indicates
that the area is subject to flooding and wave action.

3. Socioeconomic Setting. According to census figures, over the last 20
years, the Ewa region has experienced population growth at almost twice the rate
of the rest of Oahu. In 1970, Ewa's population was 24,087 persons. During the
1980's, the population increased to 38,324 persons, which is an increase of 59 per
cent. By 1990 the population had increased to 42,983 persons, or another 12 per
cent. New development projects in the area are expected to significantly add to the

133

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135

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136

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137

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Figure 40. Ewa Beach Flood Insurance Zoning.

139

population in Ewa. The Ewa Development Plan has targeted new growth in the
region. By the year 2010, the population is expected to be between 119,940 to
132,934. This is an increase of 77,000 to 90,000 people. With the increase in
population will come an increased demand to use Ewa Beach.

At Ewa, approximately 50% of the jobs are related to the military. About
39% of the jobs are actual military jobs. Another 19% of the jobs are service
related. As the Ewa area grows in population, the number of jobs related to the
military is expected to decrease.

In 1990, the median price for a owner-occupied home in the Ewa region was
lower than in the rest of Oahu. It is unknown what will be the effect on Ewa
house prices from new development projects, and the construction of some
affordable units.

There is a wide range in the quality, maintenance, vintage and value of the
beachfront homes in Ewa. Some of the homes are simple one-story units that are
relatively old and poorly maintained. A few houses, most noticeably at the east
end of the beach, are newer, with a more elaborate design and well-manicured
yards.

4. Physical Setting. The study area is bounded by an emergent reef rock
bench to the west and Ewa Beach Park to the east. Offshore, there is a shallow
reef platform with water depths ranging from 3-6 feet. The width of the platforin
is irregular, and ranges from 1,000 to 2,000 feet. The shallow water over the reef
limits the wave height acting on the beach.

The area is directly exposed to summer South Pacific swells, local Kona
storm waves and infrequent hurricane generated waves. In addition, northeast
tradewind waves may refract around Diamond Head, and winter North Pacific swell
may refract around Barbers Point to hit the Ewa Beach area. Annual longshore
direction suggests Southern Swell has the dominant influence on nearshore wave
energy, but other wave types have the potential to erode Ewa Beach effectively.
For more details on the characteristics of the different Hawaii wave types, the
reader is referred to previous studies (see, e.g., Moberly & Chamberlain, 1964).

The sand at Ewa is generally medium to coarse grained, poorly sorted and
predominantly calcareous (Moberly & Chamberlain, 1964). The beach at Ewa is

140

narrow, and portions tend to have a steep profile, especially to the east near Ewa
Beach Park.

Longshore sediment transport at the west end of Ewa appears to be towards
the west. This is indicated by the erosion and accretion patterns adjacent to a
drainage channel that extended perpendicular to the shoreline into the tidal zone.
Historic aerial photographs show that this channel acted like a groin, causing
accretion on the updrift side (towards the east), and erosion on the downdrift side
(towards the west). Because of the influence of the drainage channel, the structure
was removed from the tidal zone in 1985.

5. Historical Shoreline Chany-res. Although the beach at Ewa appears stable
(Sea Engineering, 1988), many seawalls have been constructed, thus there is some
question regarding the natural erosion or accretion trend on the beach. Homes
along this reach were built close to the vegetation line and need the protection of
seawalls during periods of high wave or storm activity. Instability along much of
this reach may have been greater than normal during the 1958 to 1967 period.
During this time, many of the nonconforming seawalls were constructed (Hwang,
1981).

6. Beach Management Problems. By the year 2010, the population in the
Ewa region may more than double. This will lead to an increased public demand
to use Ewa Beach. While the demand to use the beach may increase, the actual
size of the recreational beach may decrease.

Over the years, an ever greater percentage of the shoreline has been spanned
by seawalls and revetments. Along the area of interest, there are 118 lots. Of
these lots, there are 20 illegal structures, 56 nonconforming structures, 17 legal
structures, and 25 lots with no seawalls or revetments. Nonconforming structures
are those structures without a permit that were built before 1970. Illegal structures
are those structures that were built after 1970 without a permit.

During high tide or high wave activity, the beach is sufficiently narrow that
access may be blocked and recreational activity impacted by waves breaking
against the seawalls. Along the west end of the area of interest, the beach in front
of a span of seawalls is narrow (Fig. 41). Further to the west, one resident reported
that the beach in front of his property had disappeared over the last 10 years (Fig.

141

.44

@: - 01@
4@
i@@ ei, Lan

IC,

Figure 41. Ewa Beach - West End. Looking east from the west end of Ewa Beach. The beach
in front of this span of seawalls has narrowed and is preconditioned for loss. Care must be taken
so that beach degradation or loss does not propagate to the east.

NOW-

MAW

Figure 42. Ewa Beach - West End. Looking west from the west end of Ewa Beach. Residents
report that in the early 1970's, sections of this shoreline were covered with sand.

142

42). These problems may become more severe if sea-level rise were to continue or
accelerate.

:A
The Department of Land Utilization of the City and County of Honolulu
evaluates -requests for variances from the shoreline setback law. Variances may be
requested for new seawalls or for after-the-fact permits for illegal seawalls. The
Department must decide whether to allow the continued proliferation of seawalls
and the fin-ther degradation of the beach. Alternatively, the Department could deny
such variances. Without the proper shore protection, many of the coastal properties
would be subject' to periodic wave inundation and periodic erosion. The
Department turns to the Division of State Beaches for assistance.

7. Alternatives.

a. Sand Replenishment. A Division of Beaches would determine if sand
replenishment for the entire stretch of Ewa Beach is feasible. The Ewa Beach
littoral cell stretches over two miles in length. The east end of the littoral cell is
at Iroquois Point, and the west end at the emergent reef bench opposite Muumuu
Place. Such a long stretch may be prohibitively expensive to replenish with State
fimds. Most importantly, although the offshore reef at Ewa serves to block some
incoming wave energy, preliminary indications are that some offshore structures
would be needed to contain the replenished sand. This would considerably add to
the cost of a project to replenish the entire beach.

It may be possible to divide the littoral cell at Ewa. The City and County
storm drainage channel is one likely terminal point. A sand replenishment project
that spans the shoreline from the drainage channel to the west end of Ewa Beach
may be feasible. Since littoral drift near the storm drain, appears to be to the west,
an extension of the channel to act as a terminal groin should not affect the updrift
or east portion of the beach. In fact, before the City and County removed the
portion of the channel that 'extended into the tidal zone, there was a slight build up,
or accretion of sand, to the east of the channel.

Between the storm drain'and the area east of Muumuu Place, a sand fill
covering approximately 2,000 feet of the shoreline could be placed. Offshore
structures may still be needed to contain the artificial beach fill. The types, amount
and cost of offshore structures cannot be determined at this time, since it was
beyond the scope of this report to conduct coastal engineering studies at the

143

particular site. Offshore structures, such as a series of detached breakwaters could
be very expensive. Offshore breakwaters could cost thousands of dollars per linear
foot. With further study, cheaper alternatives to reduce offshore wave energy may
be found, thus allowing sand replenishment to proceed along this stretch.

Due to the potential need for offshore structures, a coastal engineering study
would be required to develop the sand replenishment option at the west end of Ewa
Beach. A proposed Division of State Beaches would have the option to hire a
coastal engineer, or conduct the study in house. The study could be paid for by a
contribution from a State Beach Fund. Because of the potential need for offshore
structures at Ewa Beach, this report developed the replenishment option at Kahala
Beach, where preliminary investigations indicate that no offshore structures would
be needed.

b. Buried Structures. Sand replenishment at the west end of Ewa Beach
does not address the issue of beach degradation versus shoreline protection for the
remainder of the area. Clearly, other alternatives are needed for Ewa.

One alternative for the City and County would be to move illegal erosion
control structures inland. By moving the structures inland, some protection is given
the homeowner while the beach can assume a natural profile (Fig. 43). Just as
seawalls in the tidal zone can make the beach narrow, the removal of these walls
may allow the beach to reappear.

The City and County of Honolulu, Department of Land Utilization has had
some success in requiring landowners to relocate erosion control structures. Along
one section of south Lanikai Beach, homeowners had originally constructed
seawalls and boulder piles that extended into the tidal zone. These structures
resulted in the loss of beach and the blockage of public access. The City and
County required the homeowners to remove the barriers and build gently sloping
revetments solely on the landowner's properties. By removing the. barriers, the
beach returned to a natural profile. Recreational use and public access were
restored.

This report recommends the use of buried structures such as revetments. The
burial of the revetment removes the barrier away from the active swash zone. It
should be cautioned, however, that the environmentally beneficial effects of the
buried revetment may be temporary. During periods of erosion, the revetment may

144

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become uncovered and affect nearshore sediment transport. Nevertheless,, the
gently sloping buried revetment can be used in conjunction with sand replenishment
to provide long-term protection to the landowner while helping to preserve the
recreational beach. If a sand replenishment project were to materialize for the west
end of Ewa, the existence of the buried revetment would not interfere with the
artificial beach fill.

One disadvantage of the buried revetment is the amount of space it takes up
along the shoreline due to the gentle slope and multiple layers. For many
properties at Ewa Beach, the buried revetment would not be feasible because of the
lack of space between the houses and stabilized shoreline (Fig. 44). Some of the
properties are less than ten feet from the seawall. On the other hand, there are
some homes where the setback is up to 60 feet.

Another problem with buried revetinents is the cost. A buried revetment may
cost up to $400-$500 per linear foot depending on the specific design (DHM inc.,
1990). For an average lot at Ewa Beach with a width of 60 feet, the cost of the
buried revetment would range from $24,000 to $30,000. Some of this cost could
be substantially reduced if individual landowners were to cooperate by building the
buried revetment together.

In order to deal with the illegal vertical seawalls at Ewa, a program can be
developed whereby vertical seawalls are converted to buried erosion control
structures. For instance, the county could create an overlay district that
encompasses all of Ewa Beach. Within the overlay district, the only structures that
7
would be allowed would be buried structures. Specifications can be designed on
the types of buried structures that would be suitable, given the typical beach profile
and wave regime in the district. The county could then coordinate the activities of
adjacent homeowners so that structures are built according to the district design.

. 7 The Department of Land Utilization has received shoreline -setback variance
applications for the use of buried gravel berms. By increasing the berm height, the
potential for flooding or wave inundation of the property is reduced. In addition,
there would be no wave reflection off the buried berm, leading to the narrowing
or loss of the beach. Care must be taken, however, that if the gravel berm is
exposed, the individual stones are not moved by wave action and spread along the
beach.

146

The county could set fines for homeowners who have illegal vertical
seawalls. The fine may be based on many factors, including the degree of the
violation, the potential impact on the adjacent beach, the value of the properties,
the distance of the house from the seawall, or the need for shoreline protection (see
Chapter VIII on enforcement). Although, the county agency has some discretion
in setting the fines, some degree of uniformity should be strived for. Therefore,
the county may wish to develop a formula that relates these factors with the
amount of the fine.

For residences that are so close to the shoreline that removal of an illegal
seawall could threaten the house, low-level fines of $1,00042,000 per year should
be considered instead of hardship variances. Money from the fines could go into
the Beach Enforcement Fund administered by the county. The Enforcement Fund
could then be used to provide subsidies to those landowners who convert illegal
vertical seawalls to buried erosion control structures. The subsidy could have
maximum limits, such as $7,500, or 20% of the cost of the. revetment, whichever
is less. For those landowners who have legal or nonconforming seawalls, no fines
would be imposed. However, some of these homeowners may be eligible for the
subsidy if they remove their vertical seawall, or convert the wall to a buried erosion
control structure. The county could investigate the possibility of varying the
amount of the subsidy depending if the vertical seawall removed is illegal,
nonconforming, or legal.

The county would work with the Division of State Beaches in at least two
ways. First, the Division could help the county develop specifications for buried
erosion control structures, such as a revetment or gravel berm. The guidelines
would consider the local wave conditions, the type and depth of the substrate, the
minimum lot size, and the procedure for the placement of the structures. Second,
if the county Enforcement Fund was depleted, the Division could provide, through
the.Stiie Beach Fund, subsidies to convert vertical seawalls to buried erosion
control structures. The coordination between the State and county in providing
subsidies for conversion would need to be worked out by the proposed Division.

c. Relocat'on or Removal. A few houses at Ewa Beach are less than ten feet
from the edge of a seawall. For these homes, there is simply no room to build a
buried erosion-control structures. Many of these homes have a very narrow beach

147

in front of their properties. In the event of continued sea-level rise, the risk from
coastal flooding and wave damage may eventually become intolerable.

If any of these homes are damaged by a storm and or by flooding, the State
could offer to purchase the homeowners land with monies from the State Beach
Fund. Monies from the Fund could be used to remove damaged buildings, tear
down existing seawalls, build flank erosion protection for adjacent properties, and
cover the lots with coastal vegetation such as naupaka or hinahina.

Some homeowners at Ewa Beach may be covered by National Flood
Insurance. If homeowners were to qualify under the Upton-Jones amendment, they
may become eligible for advance insurance payments before there is actual
damage to the property. The payments could be used to demolish the structure, or
relocate it, if there is sufficient space on the lots. When the insurance payment is
combined with a State contribution to purchase the land, significant economic
incentive is created for landowners to escape potential problems with erosion. In
addition, the public may benefit if the beach were to be recovered.

B. Kahala Beach.

1. Location. The beach at Kahala is located along the southern shore of
Oahu, between Kupikipikio Point (Black Point) on the southwest and Waialae
Beach Park to the northeast (Fig. 45). This distance is approximately 6,500 feet.
However, the area of interest for this report is the southwest portion of Kahala
where a recreational beach has been lost (Fig. 3). This is a distance of
approximately 2,250 to 2,500 feet. This area is covered by tax map keys 3-5-2;
3-5-3; and 3-5-4.

2. Zoning. The Kahala area is designated as Urban on the State Land Use
District Map (Fig. 46). The area is zoned for residential use on the Oahu
Development Map (Fig. 47). The homes in Kahala are zoned R-5 and R-7.5 (Fig.
.48). The R-5 zoning requires a minimum lot area of 5,000 square feet and a
minimum lot width of 50 feet for a single family detached dwelling. The R-7.5
zone requires minimum lot areas of 7,500 square feet and minimum lot widths of
65 feet. On the National Flood Insurance maps, Kahala beachfront homes are in
the A zone, which indicates there is a threat from coastal flooding (Fig.49).

3. Social Seqin&. The backshore of Kahala is developed with high priced

148

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Figure 45. Kahala Beach Location.

149

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Figure 46. Hawaii Land Use District Map for Kahala.

150

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Figure 47. Oahu Development Plan Map for Kahala.

151

P, 2
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Figure 48. Oahu Zoning Map for Kahala.

152

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Figure 49. Kahala Beach Flood Insurance Zoning.

153

single-family dwellings. A recent article in the Honolulu Advertiser, March 16,
1992, reports that at Kahala, a six bedroom, seven bath shorefront house with two
adjoining vacant lots was listed at $23.5 million. A six bedroom, seven bath house
away from the beach - though not listed - was reported to have a price of $8.9
million.

Although Kahala Beach has the stigma of being exclusive, the beach is not
significantly different in terms of public access, or parking to any other beach lined
with private homes. At or adjacent to the area of interest, there are three public
access-ways. Thus, the requirements of Hawaii Revised Statutes Chapter 115,
regarding public access to the shoreline, are met. For many residents of Honolulu,
Kahala Beach provides an alternative to the use of Ala Moana Beach Park and
Waikiki. It is the only beach easily available to Honolulu residents between Ala
Moana and Sandy Beach Park (Sea Engineering, 1991). The beach at Kahala is
used for diving, pole fishing, snorkeling, board surfing, swimming and sun bathing.

4. Beach RecoveKy. There are a number of littoral physiographic features at
Kahala that would promote a successful beach restoration project. These include
distinct littoral cell termination points, predictable. wave climate and sediment
transport patterns, a proximal sand source, and a natural containment basin. A sand
replenishment project at west Kahala could provide the public with renewed
recreational and environmental benefits at a low cost and with relatively few
associated sand containment structures.

The wave climate at west Kahala Beach is seasonal with low, long-peniod
southern ocean swell dominating between April and October. These waves
typically range between I to 4 ft and 14 to 22 seconds, although higher waves
approaching 6 ft are not uncommon. When northeast tradewinds weaken and Kona
storms develop, high waves and strong winds from the southwestern quadrant may
occur at the Kahala coast. Kona storm waves may approach during the winter
months with heights of 10 to 15 ft and periods of 8 to 10 seconds. The majority
of wave energy is dissipated on the seaward reef crest at Kahala. The reef is
consistently shallow in the longshore direction, making it an effective energy
bamier for the adjacent beach. Field observations during a period of strong
southern swell ranging from 6 to 8 ft. and averaging 15 to 18 seconds at the reef
crest, revealed that wave conditions behind the reef vary over a tidal cycle (Fig.
50). At low tide, portions of the back-reef flat are exposed, and wave energy on
the beach is negligible. At high tide, wave transformation in the back-reef basin

154

Figure 50. Kahala Beach. TOP: At lo@@, tide portions of the reef flat are exposed, the waterline
is well seaward of the base of existing stabilization structures, and the wave energy is negligible
t ide the reef crest. BOTTOW At high tide on the same dav the waterline has ri
1, _-,I
ns) I isen to a
position well above the base of the seawall and wave enerov has increased significantly. Strong
southern swell on this day generated breakim, %@-ave he[ghts in excess of 6 ft. on the reef crest.

15S

leads to short period 3 to 6 second waves with heights of I to 2 feet. In many
cases, these secondary waves break directly on the seawalls at Kahala and produce
splash heights off the seawalls in excess of 10 ft. These waves appear to have
significant erosion potential.

Both southern swell and Kona storm waves approach from the south to
southwestern quadrant and generate a northeasterly longshore current at Kahala.
This current strengthens to the northeast as it approaches a distinct channel in the
reef slightly northeast of Hunakal St (Fig. 51). The reef channel is the primary
feature allowing return flow to the offshore region. Currents in this channel were
observed to exceed speeds of 3 ft/sec. at peak ebbing tide during high wave
conditions. The littoral circulation pattern at west Kahala is driven by wave energy
flux across the reef crest and return flow through the reef channel.

Marine sand resource investigations (Coulbourn et al., 1988) identify
substantial sand deposits offshore of the base of the west Kahala reef. Sampling of
deposits at a depth of 25 ft at the mouth of the reef channel show these to be
well-sorted, coarse to very coarse carbonate sands of good color. In the original
investigations of Moberly and Chamberlain (1964), sand samples from the berm at
Kahala beach measured in the medium to coarse sand range, samples from the
beachface at sea level measured in the upper coarse sand range, and samples from
immediately offshore of the beach ranged from fine sand to very coarse sand.
While further investigations are needed such as described in Chapter VI, at a
preliminary level it appears that a potential sand resource for nourishing west
Kahala beach may be found immediately offshore of the adjacent reef. These sand
fields are not tied to the littoral sands of the Kahala shoreline so that their removal
by mining will not effect onshore sand bodies. The marine sand can be most
effectively mined by a submersible pump dredge and pumped directly onshore by
pipeline. The fill should be desilted by a dewatening cyclone (Noda, 1991) at the
discharge end of the pipeline, and the cyclone slurry pumped offshore following
careful study of optimal dispersion pathways and currents.

The geometry of the fill should approximate the original 1:7 slope of the
beach at west Kahala prior to its loss (Moberly and Chamberlain, 1964). A project
length of approximately 2,400 ft is suggested, or from the east side of Kupikipikio
Pt. where it-meets Kahala beach to the shoreline nodal point adjacent to Ulili St
(Fig. 52). The design subaenial beach (honizontal) is 100 ft wide to the berm crest,
with a 1:7 offshore slope beyond this point. The fill berm height is 6 ft above msl

156

xR
8 m

J<upikipik' t

Figure 51. Circulation Pattern. The littoral circulation pattern inside the reef at west Kahala is
driven by wave energy flux across the reef crest and strong, channeled return flow through the
break in the reef adjacent to Hunakai St. Circulation strengthens to the northeast and
approaching high fide.

157

6 M

25 k.
'Kupikipiki@o Rt

Figure 52. Kahala Beach Nourishment Project. Aspects of the nourishment project including fill
geometry, and terminal groin placement.

158

at. 100 ft from the present stabilized shoreline.. Subaerial fill thickness is a total of
9 ft which includes a basal thickness-of 3 ft Of fill to present msll,'and an additional
6 ft to reconstruct the subaerial beach to the former berm height. The total
subaerial fill volume is 80,000 cu yd (9 ft x 100 ft x 2400 ft). Offshore of the
berm, the fill is calculated as a triangle with a slope of 1:7, giving a volume of
25,200 cu yd. This approximates the original beachface planform and geometry in
terms of berm height, run-up distance, and waterline position.

These calculations provide an approximate maximum total fill volume of
105,200 cu. yd. Moberly and Chamberlain (1964) measured the sand.volumie at
Kahala. The total offshore and onshore volume was calculated at about 45,000 cu
yd. This is a useful minimum total fill volume. Noda (1991) estimates a cost of
$12.50/cu yd for marine sands close to the Waikiki project site. As mentioned
previously, there is good potential for quality nearshore sands makai of the reef
crest at Kahala Beach. Using technology similar to what would be employed at
Waikiki, a $12.50/cu. yd. cost appears to be a reasonable estimate for nearshore
sand. Based on these figures, the sand fill at west Kahala would cost between
$562,500 (min.) and $1,315,000 (max.). Variables influencing this cost include the
lack of technological infrastructure in the State for conducting a nourishment
project, questions regarding the actual fill volume needed, the overfill factor, and
the. quality and availability of the sand resource at Kahala. Presumably, costs will
decrease if the Waikiki restoration project develops the technological infrastructure
that can be used on Kahala Beach. For example, one option at Waikiki that is
receiving favor is to use a hydrocyclone to dewater and desilt nearshore sand and
pump it on the beach by a pipeline. If the State were to develop this technology
and purchase this equipment for the Waikiki project, then any suitable nearshore
sand that is identified at Kahala could be placed on the beach with a signifi cant
reduction in cost.

Some structural activities are needed in association with sand replenislunent.
Prior to fill placement, as many as possible of the existing vertical seawalls and
steep revetments at Kahala should be removed. If they stay in place, they may
eventually begin to interact with the wave environment and cause excessive erosion
if there is a storm or hurricane. Once existing structures are removed, the upland
should be graded at a 1:3 slope (or less) to the level of the fill. The graded slope
should be landscaped with rapid and thick-growing vegetation, and landowners
prevented from any construction other than inland of the certified shoreline.
Although it is preferable to avoid the use of any shoreline stabilization structures,

159

property owners may be permitted to construct buried 13 revetments such that the
seaward toe of the structure is located on their'property, and t1fe revetment extends
landward across private land. The revetment should. be buried at all times, and
should be reburied if -there is erosion that uncovers the structure.

The possibility of installing a low, terminal weir groin at the northeast end
of the fill should be investigated. Such a structure may extend the life of the
project, and decrease the frequency of renourishment by stabilizing the end of the
fill and decreasing the sand loss to longshore drift. Since there is presently no sand
on the. west Kahala coast, a terminal groin could not interfere with normal sand
flux to the northeast. Care must be taken, however, not to extend the groin too far
beyond the waterline as some leakage of sand into the littoral system should be
encouraged to help maintain the beach to the northeast. Studies should also
determine the optimal orientation of the groin, and the benefits derived from
curving the tip to the southwest to provide additional stability. The groin should
be low enough that the onshore portion is buried by the fill, and that the offshore
portion does not present a safety hazard.

As calculated in Chapter VI, the Bruun Rule estimates for Oahu suggest that,
under current rates of sea-level rise, the nourishment project will experience
recession of 4.6 ft/dec; for projected rates of sea-level rise next century, recession
may occur at 18 ft/dec. Under present sea-level rise the renourishment
requirements for the southwest end of Kahala will be about 1073 cu yd/yr, which
equals an expense of $13,415 averaged annually. This recession rate and the
attendant expenses are based on sand losses due to sea-level rise only. Storms and
high wave events will inevitably accelerate the recession rate and increase the costs.
The average annual costs for renounishment due to sea-level rise will fall
somewhere between $13,415 (present sea-level rise rate) and $52,703 (projected
future sea-level rise rate). Thus, escalating costs for maintaining the beach should
be expected in connection with the potential for accelerating sea-level rise in
coming decades. In addition, these costs should be increased by an unknown factor
to compensate for storm and high wave erosion.

A number of considerations should be addressed prior to implementation of
the west Kahala beach nourishment project. These are:

a. Careful sampling of the offshore sand source at Kahala to determine fill volume,
grain settling velocity characteristics, sorting and silt content, and cementation.

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b. Modeling of the equilibrium beach profile under the seasonal wave climate using
native grain characteristics, and also with the characteristics of the potential fill
sand from offshore.

c. Determination of historical storm frequency and magnitude at west Kahala, and
estimates of the impact of storrn events on renourishment needs and scheduling.

d. Monthly profile surveys of the existing beach at east Kahala to determine annual
beach volume changes and their causes and littoral transport patterns.

e. Consideration should be given to the potential for water column siltation'and'
associated impacts to the adjacent reef community.

Finally, it is of critical importance to the success of both this and all other
nourishment projects in the State that the fill be regularly, frequently, and precisely
monitored over the long-term in order to fully assess the factors governing stability,
economic viability, and response to sea-level rise and wave parameters. The State
needs to build an empirical database to make accurate predictions on fill life and
performance. In addition, the science of predicting beach response to sea-level rise
presently lacks a high-precision, long-term database for developing more sound
numerical models based on oceanographic conditions. Monitoring must consist of
a detailed onshore and offshore component, an accurate description of wave
climate, and regular calculations of beach volume and surface area changes with
corresponding data on the hydrodynamic and meteorologic field.

5. District Formation. In order to recover the beach at Kahala through sand
replenishment, a Beach Management District would need to be formed using
overlay and improvement district concepts. The exact boundaries of the district
could be determined. at a later date, when additional coastal studies define the
terminal boundaries of the artificial beach fill. The approximate district boundaries
would be at the intersection of Kahala Beach with Kupikipikio Point and the nodal
point at Kahala Beach opposite Ulili St. The northeast part of the Kahala Beach
Management District would be a zone that marks the transition from the artificial
beach to the southwest with the natural beach to the northeast.

The district is expected to cover a distance between 2,200-2,400 feet. There
are approximately 25-27 lots along this stretch. The exact number of lots can be
determined after the terminal points of the beach fill are calculated. Data from the

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Department of Land Utilization (DLU) indicates that of the lots along this stretch,
approximately 281/o-. have legal seawalls and revetments, 32% of the'structures are
nonconforming, and 40% are illegal. Depending on the legal status of the erosion
control structure, there may be different opportunities and constraints regarding
district formation, fines, and the removal of the structures (Table 8).

If a sand replenishment project were to materialize at Kahala, one of the first
steps of the DLU would be to initiate the formation of an overlay district. In the
district, landowners would be required to remove illegal vertical walls and steep'
revetments..- A.-fine could be placed on illegal structures, -with the monies going
into a county enforcement ftind. The fine should be based on numerous factors
such as the degree of the violation or the impact on the beach. An additional factor
that should be considered in setting the fine is that the area is being prepared for
a sand replenishment project. The presence of the illegal vertical seawalls could
result in the seaward transport of artificial sand.

Substitute erosion control structures such as buried revetments may be
allowed for homeowners that remove their seawalls. By converting the vertical
walls to buried structures, the shoreline is prepared for sand replenishment at a later
date. As in the example for Ewa, subsidies from the County Enforcement Fund,
or the State Beach Fund could be provided to help in the conversion.

For legal or nonconforming seawalls, there is no mechanism to require
homeowners to remove the vertical walls. However, for nonconforming structures,
it may be possible to phase out the use of the nonconformity with a retirement or
amortization schedule. This process could take many years, and may delay the
formation of a district.

Incentive to remove legal and nonconforming vertical seawalls and convert
to buried structures is provided in several ways. First, subsidies could help
landowners make the conversion. The administering agency could consider
granting a larger subsidy for legal and nonconforming structures as compared to the
subsidy for illegal structures. Besides economic incentive, there is another reason
for landowners to convert. Many of the vertical walls along the beach could be
undermined (Fig. 53). As sea-level continues to rise, collapse of the walls may
become more common. The effect of a water level rise on the gently sloping beach
at Kahala has been shown previously (Fig. 50). From the perspective of long-term
property protection, the landowner may have more protection with a gently sloping

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Table 8 - Legal Status of Erosion Control Structures.

Legal Status Fines Removal Forced Compliance
(BMD)

Illegal Fines can be imposed. Any illegal structures in Must comply with
HRS 205A-32 the shoreline setback area overlay regulations
provides for a one- without a variance can be regardless of legal
time fine of up to removed (HRS 205A- status.
$10,000, and/or a 43.6).
$1,000 per day fine
for SMA or Shoreline
-Setback violations.

Nonconforming No Fines No immediate removal. If the majonity of
Structures can be phased landowners consent to
out according to an the formation of an
amortization schedule for improvement district,
commercial, industrial, then the holdouts can
resort, and apartment be forced to comply.
zoned areas. No This is usually enforced
amortization for existing by placing a lien on the
single family buildings or holdout's property.
premises (HRS .464). It
is unclear if a seawall is No regulation was
part of a building or encountered that forced
premise. Other coastal compliance as a penalty
states have amortization for illegal activity. It
schedules for the removal appears that
of seawalls. compliance may be
obtained indirectly.
(See next section on
landowner cooperation).

Legal No Fines No immediate removal. No forced compliance
However, new rules can to sign an indemnity
be passed that make legal agreement regardless of
structures nonconforming. legal status. An
indemnity agreement is
a contract that requires
volitional consent of the
parties for proper
formation.

buried revetment that has a well maintained artificial beach in front. Finally, a
restored beach at Kahala would enhance recreational opportunities and improve

163

Aim&

-Ape

160-

Figure 53. Seawalls at Kahala. TOP: During low tide, the effects of wave attack can be seen
at the base of seawalls. BOTTOM: At the northeast end of the area of interest, this seawall
collapsed due to the undermining of the base by wave action.

164

scenic views, thus adding to the value of the coastal property. These benefits
would need to be conveyed to the landowners.

The possibility exists that a number of vertical seawalls along the stretch of
Kahala Beach cannot be removed. One solution would be to form the district only
for those sections of the shoreline where the seawalls are removed. Alternatively,
the project could proceed with some offshore barrier that reduces wave energy
before it reaches the vertical seawalls. This would add cost to the overall project,
and require fin-ther coastal study. In addition, while the nonconsenting landowners
to pay for
may legally refuse @ to remove their seawalls, they may not refusd'
improvements that benefit their property. Therefore, the landowners actions -would
increase their cost in the project as well.

6. Landowner Cooperation. In order to finance a sand replenishment project,
an improvement district would need to be formed. The improvement district would
require the consent of a certain percentage of the shoreline property owners.

The presence of illegal shoreline structures may provide some opportunity
for the State to procure landowner consent to join an improvement district. In a
survey of coastal statutes for different states, no provision was found that forced
cooperation in an improvement district as a penalty for illegal activities along the
coast. Nevertheless, it may be possible to obtain landowner consent indirectly. For
example, the counties may force the removal of illegal vertical seawalls (HRS
205A-43.6). The types of erosion control measures along the shoreline to those
that require the implementation of a district. Thus, incentive can be created for the
landowner to join the district in order to mitigate erosion of their property. In
addition, the State has the power to fine illegal activities (HRS 205A-32). Fines
for the illegal activity can be used to pay f6r the improvements in a Beach
Management District.

It would be the Division of State Beaches that develops rules and criteria for
the formation of a Beach Improvement District. One set of rules would deal with
the level of landowner cooperation to form an-improvement district. This report
suggested setting the initial level at 80% to reduce the problem with nonconsenting
landowners '(the Oahu improvement district ordinance requires a 60% level of
cooperation). Where liability may be high, 100% landowner cooperation may be
required. The Kahala sand replenishment project would not be considered high risk
since the properties are likely to have some structural barrier, such as a buried

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revetment, behind the artificial beach fill. If the beach were to disappear, the
barriers could provide emergency protection.

If 80% of the landowners do not approve of the improvement project, then
the Kahala replenishment project would be rejected by the Division of State
Beaches. Assuming 80% of the landowners approve of the project, this analysis
will proceed.

7. Cost Allocation. As discussed in section 4 on beach recovery, thecost to
replenish the west end of Kahala Beach will range from $562,500 to $1,515,000
depending on the actual size of the beach fill. This cost would be shared, in
different amounts, by the State, the county, the landowners and possibly the Federal
government.

a. Federal. Under the Rivers and Harbors Act, Federal assistance is available
for small erosion control projects that benefit the public and the private sector. The
amount of the Federal assistance is to be adjusted depending on the degree of
public benefit. The contribution is not to exceed one-half of the total cost of the
project. Thus, there is the requirement that the State or local government provide
matching funds.

Assuming Hawaii was eligible for such benefits by establishing a funding
mechanism similar to that discussed in this report, then the Division of Beaches
would actively seek such assistance for all replenishment projects. For discussion,
it is assumed that the Division of State Beaches has petitioned the Secretary of the
Arrny for Federal assistance and was able to procure a contribution of $250,000.

b. Landowner. For the improvement district, landowners are also assessed a
portion of the cost. The landowner assessment ranges, as suggested in this study,
between 30% to 45% of the cost, depending on the amount of public benefit. For
this section of Kahala, the landowners are assessed 45% of the total cost. The
landowner assessment could have been lower if there was better public parking.
The assessment could have been as-low as 30% if the project site was adjacent to
a pubic beach park.

The landowners cost is adjusted for any Federal contribution. In this
example, the landowners at Kahala must pay 45% of $312,500 to $1,065,000.00.
Therefore, the landowner's fractional cost would be between $140,625 and

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$479,250. Divided between approximately 26 homes in -the District, the average
amount each landowner would pM would range from $5,40 to $18,433. However,
the exact amount each landowner would pay is based on an assessment formula
that includes, as one factor, the lin"ear footage along the shoreline. The narrowest
lot along this stretch spans 10 feet of the shoreline while the widest covers almost
100 feet. For the narrow lot, the assessment would be between $611 to $2,084.
For the widest lot, the assessment would be between $6,114 to. $20,837.

Individual, landowners could be given the option of contributing more than
their assess metit into-the State-.Beach Fund to,receive a State tax deduction. -..Such
a program may lead to pleasant surpnises in the amount of contributions received
by the assessed landowners.

c. County. County cost would be between 10%-20% of the total cost of the
project less any Federal contribution. If the counties were to cooperate with the
State and grant a I% to 2% reduction in property assessments for beachfront homes
that are in compliance with all regulations, then the State could pick up a greater
share of the cost. In this instance the county contribution would be 10% of the
total cost, or $31,250 to $106,500.

d. State. The State would pay 60%-45% of the cost, less any federal
contributions. The amouzit of the State payment will be dependent on the public
benefit of the project. For the Kahala example, the cost to the State would be 45%
of $312,500 to $1,065,000. This would amount to $140,625 to $479.250, taken
from the State Beach Fund.

In Table 9, there is a breakdown of costs for the State, the county, and the
landowners using several scenarios. The high cost estimate a:ssumes a beach fill
of 105,200 cubic yards of sand, a price of $12.50 per cubic yard and no Federal
contribution. The low cost estimate assumes a beach fill of 45,000 cubic yards of
sand, a price of $12.50 per cubic yard and a Federal contribution of $250,000.
Using the high cost estimate in column 1, the average landowner's contribution
would be $22,760. It should be noted that this cost is less than the $39,600 cost
to build a buried revetment (Assuming an average lot width of 88 feet and the cost
of the revetment at $450/linear foot).

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Table 9 - Breakdown of Costs for Kahala Beach Sand Replenishment.

Party Hi Costs Hi Costs Low Costs Low Costs
No Fed. Fed. Contrib. No Fed. Fed. Contrib.
Contrib. Contrib.

Each
Landowner $22,760 $18,433 $9,736 $5,409

County $131,500 $106,500 .$56,250 $31,250
..LState $479,Z5 1. $253,125. 25.
1.$591,750 $140,6

For the City and County of Honolulu, there would be a cost of $131,500 to
pay for their share in the Beach Management District. This is not much,
considering the close proximity of Kahala Beach to the residents of Honolulu.

Finally, the State share for the replenishment project would 'be $591,750.
Interestingly enough, the revenue from the sale of a 15 million dollar home in
Kahala can generate income of $300,000 from the 2% shoreline property- transfer
tax. This money goes into a State Beach Fund, which can be used to pay for the
State contribution to replenish Kahala Beach. The money from the transfer tax
would pay for half of the State contribution. Thus, when a shoreline property is
sold, revenue that is generated can be used to benefit the existing beachfront
homeowners, the State, the county and the public.

With the projected acceleration in sea-level rise, the annual cost to maintain
the beach would be $52,703 per year. Before a district is formed, an agreement
would be needed between the State, counties and landowners on a maintenance
schedule, and the allocation of costs. Some coastal states require that landowners
are entirely responsible for maintenance cost. Assuming landowners are made
responsible for maintenance, when the annual cost is divided by 26 properties, there
is an average cost of $2,027 to maintain the beach. These costs are very
reasonable considering the value of the property protected.

It is believed that many of the costs could be significantly reduced if a State
office was established to develop the technological infrastructure to conduct
continuous sand mining operations.

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XI. RECOMMENDATIONS

In this report recommendations are made that fall into three categories. First,
there are recommendations related to the implementation of Beach Management
Districts at the State and county level. Second, there are recommendations related
to the two case study sites at Kahala and Ewa Beaches. Finally, there are
recommendations related to beach management in general.

A. Beach Management Districts

This report recommends the use of improvement and overlgy districts to heIR
in the management of the State's beaches.

The Hawaii Land Use Enabling Act gives the counties the authority to
establish, both overlay and improvement districts. In Kauai County's Zoning
Ordinance, there is a provision for overlay Shore Districts. In these districts, there
-are restrictions on seawalls and bulkheads. The district ordinance requires the use
of sloping permeable revetments when barriers are permitted. Although the Shore
District ordinance was passed in 1972, Kauai has yet to implement the concept.

The overlay shore district would give the counties discretion in protecting
sensitive or unique areas of the coast. The overlay district may be useful for
undeveloped coastlines, since additional restrictions may be placed on highly
unstable areas. For developed coastlines, the utility of the overlay district may not
be as great since the landowner may still be limited to the use of seawalls and
revetments. Nevertheless, the overlay district may give the counties the discretion
to regulate the types of erosion control structures along the shoreline. Given the
extent of the erosion problem, some type of erosion control regulation should be
considered at the State or county level.

It is through the improvement district that alternatives other than seawalls
and revetments can be developed for the landowner. The individual counties may
establish improvement districts by adopting an improvement ordinance similar to
Oahu's, or by modeling the ordinance after other coastal States. Nevertheless, some
of the counties may not be organized technically or financially to establish the
types of improvements that may be included in the district.

It is recommended that an ageng within the State be established to promote

169

and administer Beach Management Districts.. Although, the exact procedures would.
need to be worked out by the State agency, the following are recommended as
preliminM guidelines to pay for improvements in a Beach Management District.

Formation. Provisions should be considered that allow the formation of a
district upon the petition of a State or county agency, or a group of landowners, or
the public. Regardless of the party that submits the petition for district formation,
a minimum level of landowner consent would still be required.

Cooperation. There are many reasons for lan*downe'rs'toj*oin an improvement
district, including increased property value and shoreline protection. For this
reason, the initial level of landowner cooperation 'should be made high. A
preliminary suggestion is that 80% of the landowners in the district agree to the
project. If the project is one of higher risk or liability, then 100% cooperation is
suggested. For a high risk project, the State should not form a district unless 100%
of the affected landowners sign an indemnity agreement. A high risk project may
be one in which the property owners rely solely on sand replenishment for property
protection.

Assessments. The assessment formula should include as a primary factor the
linear footage along the beach. Other factors such as value of the protected
property may also be considered, if there is a wide disparity in the quality, vintage
or value of the beachfront homes. If there is a wide range in the distance of the
structures from the shoreline, this factor may be considered in the assessment.

Cost Allocation. A shared cost system is recommended, with the State,
counties and coastal landowners paying for the nonfederal portion of the total cost
of the project. A preliminary allocation of costs is State 60% - 45%, county - 10%,
and beachfront landowner 45% - 30%. The exact costs for the State and beachfront
landowners would be dependent on the degree of public benefit derived from the
project.

Liability. All homeowners who agree to the formation of a BMD should be
required to sign an indemnity or hold harmless clause which relieves the State and
county from any liability for the failure of an erosion control structure. To reduce
liability from the public, the State would need to periodically monitor
improvements within the district for dangerous unnatural conditions.

170

Monitoring. Periodic monitoring would be required to check on the status and
condition of improvements within the district, and to check on the performance of
artificial beach fill.

Maintenance. Any improvement district which involves sand replenishment
should not be approved without a long-tenn commitment to periodic renourishment.
The schedule and allocation of costs would have to be worked out by the State,
counties and landowner.

.-B. Beach Man-agement

State Role. This study reports formidable problems along the beaches of
Hawaii. Scientific evidence indicates these problems will intensify in the absence
of an active role by the State. The State is the trustee of the beach resource. The
State should take the lead in defending against coastal erosion and sea-level rise.
it is recommended that the State establish an agency that is responsible for the
management and administration of beaches. The agency would develop and
implement many of the programs outlined in this study, as well as any other
programs that provide for the maximum long-term societal benefit from the beach
resource.

Public Education. It is essential that the problems with beach loss, erosion
and sea-level rise be conveyed to the public. It is peculiar that despite the
widespread degradation of the shoreline, there are many who feel further protection
of the coast is unnecessary. A public education program should objectively convey
the facts about the coastline to landowners, buyers, sellers, developers, planners,
engineers, government officials, elected officials and the general public. Without
an informed public, it will be difficult to implement the changes in shoreline
management which are required.

Zoning. Although attempts have been 'made in the past, the State should
make another effort to modify the shoreline setback. Using the guidelines and
programs discussed in Chapter VIII, the economic burden to landowners can be
minimized or eliminated, thereby reducing political opposition. Furthermore,
amendment of the setback as proposed facilitates future participation in Federal
programs under the River and Harbors Act and the National Flood Insurance Act.
The former Act may help in the financing of a Beach Management District@ while
the later can offer a degree of financial protection to the landowner. A properly

171

structured setback, that is no more burdensome than necessary, is the most efficient
way to ensure the preservation of the beach resource and the protection of private
property.

Research. Further research should concentrate in two areas. First, a program
of continuous monitoring should be developed using beach profiles and aerial
photography to help planners and administrators make informed beach management
decisions. Second, offshore sand sources that are adjacent to eroding beaches may
be the best opportunity to provide a cheap source of replenishment sand. However,
there are many technical, ec6nomic,. environmental. and legalls-sues that need. to be
resolved. For example, research may be. needed on the impact of sand mining on
coral reef communities. Methods to mitigate any potential impact, such as the
development of special equipment, should also be investigated.

C. Ewa Beach

The City and County of Honolulu should establish an Enforcement Fund.
Income into the Fund would be derived from fines for shoreline setback violations
and from legislative appropriations. Money from the Fund could be used for
enforcement activity and to pay for subsidies to convert 'vertical seawalls to -buried
erosion control structures landward of the certified shoreline. An overlay district
could be formed that allows only a certain erosion control design in the district.
A strategy of fines and subsidies can be used at Ewa Beach. For those residences
that are so close to the shoreline that removal of the illegal seawalls would threaten
the property, the use of low-level fines, on the order of $1,00042,000 per year
should be considered. Where the residence is further from the shoreline, the fine
could be increased so that revenue raising and deterrence are achieved. The
administering agency would have some discretion in setting, the fines, but some
degree of uniformity should also be strived for. Money from the fines can be used
to provide subsidies to convert vertical seawalls to buried structures mauka of the
certified shoreline.

The State should develop procedures so that all beachfront homeowners who
are in distress, and who qualify, can take full advantage of advance insurance
payments under the Upton-Jones amendment. For many residents at Ewa Beach,
such a program may provide additional financial protection against erosion, sea-
level rise, and storm wave damage. In order to take advantage of relocation
benefits, an amendment to the setback may be required.

172

D. Kahala Beach

Where needed, gently sloping buried revetments should be the erosion
control structure of choice for Kahala. By moving erosion barriers away from the
water line, some of the beach may be recovered. The transformation from vertical
walls to an unstabilized coastline, or one with gently sloping buried revetments
would prepare the shoreline at Kahala Beach for a potential sand replenishment
project. Conversion can take place through the use of fines and subsidies. If a
sand replenishment. project were to materialize at Kahala, an overlay district may
be needed to help prepare the shoreline for replenishment.

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XU. IWLEMENTATION GUEDELINES

The implementation guidelines in this report can be divided into two parts.
First, there are procedures to implement a statewide comprehensive beachfront
management program with beach management districts. The implementation
strategy for this program relies on establishing a State agency responsible for beach
management that develops many of the programs in this report. To install a fully
operational beach management program may take 3-4 years, assuming all legislative
and financial support is obtained. The second set of implementation guidelines
relate to action the State and .'counties can take in the interim.

A. Public Education - Changing Public Perception

Realistically, no action is likely on many of the programs in this report given
the current level of awareness and understanding about coastal erosion and beach
preservation. For example, during hearings in 1991 on House Bill 893 to establish
Shoreline Stabilization Districts and extend the shoreline setback, there was oral
and written testimony from various parties that the present system of beach
management was effective, and no ftu-ther change was necessary to protect the
shoreline. During the same legislative session, there was a proposal to establish a
State Office of Beaches within the Department of Land and Natural Resources.
Although this bill requested the relatively small amount of $100,000 to investigate
staffing and budget requirements, the bill died in the House Finance Committee.
From the failure of the legislature to implement these measures, it appears that
beach management is not an important public issue. This is unfortunate, because
in the future, the problems associated with erosion, beach loss, and sea-level rise
are likely to have ramifications equal to any other environmental issue.

It is clear that apy significant changes regarding beach management will
reguire an eggglly- significant change in @erception of the problem. Since
implementation of the programs in this report is dependent on changing public
perception, some discussion should follow on this matter.

One of the first steps in changing public perception is to emphasize the
gravity of the problem. There may be a tendency to sensationalize the material in
this report, and all effort to do so should be suppressed. Nevertheless, it is difficult
to argue with the aerial photographs that show actual beach loss (Figs. 2 through
6); the tide gauge data (Fig. 21); or the application of the Bruun Rule (Table 6),

174

Ila which is a widely accepted engineering technique that relates sea-level rise and
beach recession.

That beach loss over the last 50 years is concurrent with, and related to, sea-
level rise has serious implications. It indicates that the disappearance of beaches
is due not only to random erosion events, but is part of an overall long-term trend.
Although local conditions may change, and a few beaches may experience short-
term cycles of erosion and accretion, over the long ran, the majority of beaches in
the State will recede.

Not only is sea-level rise expected to continue, but projections 'call for an
acceleration in the rise. This has even greater ramifications, since beaches are very
sensitive to small changes in water level. The estimates in Table 3 call for a
significant acceleration in the present rate of sea-level rise by the year 2050. These
estimates should be used as maximum projections. It is probable that future sea-
level rise will fall between the current rate of sea-level rise and the 2050 projection.
Even at the current rate of sea-level rise, all gently sloping, narrow beaches in the
State that have been armored, could be lost in the next 50 years. The loss of
beaches, as documented in Chapter 2, are exactly the changes to be expected. A
continuation of the present trend would affect the integrity of coastal property,
diminish recreational opportunities for the public, and impede the tourism based
economy. If sea-level rise were to accelerate, as projected, the impacts would be
unimaginable.

The problems with sea-level rise are, sufficiently serious to warrant the
development of a public education program. The program should target the general
public as well as government officials and politicians. Not until the public is
educated can political support be gained to implement effective beachfront
management programs. In the process of informing the public, it is equally
important to address the concerns of landowners. It needs to be emphasized that
given the problems with sea-level rise, many of the programs would benefit the
landowner.

B. State Agency Responsible for Beach Management

The single most important step that the State can take to implement the
ideas and prop-rams in this Egort is to establish a State agenEy responsible for
beach management. Before there is any State Beach Fund, shoreline transfer tax,

175

sand replenishment, capital. improvements within a Beach Management District,
voluntary relocation program, or variable erosion shoreline setback, there would
need to be an administering agency at the State level. The agency could be formed
as an office, a division, or a branch. Alternatively, an existing State agency can
be given considerably expanded duties.

There must be extensive planning prior to the designation of the appropriate
agency. A bill should be submitted in the 1993 legislative session to fund this
planning. Within one year after -the appropriation of funds- a report should be
submitted to the legislature.on recommendations for the structure, organization *and
association of the responsible State agengy,- along with proposed legislation to
establish that agency.

The report would need to cover many issues, including the following:

New State Agency vs. Existing State Agency - Recommendations would be needed
on whether a new State Agency, such as a Division of Beaches, should be formed
as opposed to expanding the duties in existing agencies. The advantage of using
existing agencies is that another bureaucracy may not be required, if the capability
currently exists. This could reduce manpower, cost and overhead. The
disadvantage of using existing agencies is that beach management can be
compromised. Preexisting duties that an agency has may take precedence over
beach preservation. This could lead to "business as usual."

The advantage of forming a new State agency is that it can devote its entire
effort to beach management. In the future, the problems associated with sea-level
rise will be a major challenge for the State. The administration of programs that
deal with these problems may require the formation of a new Division (see Chapter 1w,
IX for likely scope of duties). In the long run, overall cost for a new Division may
be less, if it is more effective in preventing coastal hazards, developing low cost
erosion mitigation technology, or obtaining Federal ftmding.

Government Coordination - The report should investigate the coordination between
the counties, DLNR, DOT, CZM and the Corps of Engineers for all the programs
discussed in Chapter IX, as well as others that may be established. It is anticipated
that the duties for different programs will be shared between the counties and the
State. For example:

176

For cgpital improvements within a Beach Management District it is
anticipated that the State would pursue Federal ftinding, evaluate the
technical, economic, and environmental viability of the project,
provide permitting assistance, offer technical assistance, and pay for
a major part of the cost through a State Beach Fund. However, many
questions remain. For example, should the State or county determine
the boundaries of the District, collect the landowner share.of the cost,
or obtain landowner consent?

In the administration of a variable rate erosion setback, it i's anticipated
that a State agency would set the appropriate shoreline setback based
on the average annual erosion rate or the historical range in the
position of the vegetation line. However, the counties would need to
offer compensating land use variances if the setback was greater than
60 feet. How would the duties of the State and counties be shared
with regard to administration of the shorline setback?

These coordination issues, and others, would need to be covered in the
report. How the duties are split between the counties and the State may determine
the final structure of the responsible State agency.

Staffing and Budget - The legislative report should provide some flexibility to
adjust staffing and administrative costs at a later date, depending on what programs
are actually implemented. Therefore, the report should include temporary and
permanent budget levels for staff and administrative cost.

C. State Agency Implements a Beachfront Management Program

Once there is a responsible State agengy, it can devote thelime and energy
to work out the s@ecific details that are reguired to implement beachfront
management programs. This report briefly studied many of the programs that the
agency should investigate and develop. This report is not meant to take the place
of detailed investigation that the agency can conduct. Nevertheless, some
preliminary implementation guidelines follow.

-agency
Capital Improvements Within a Beach Management District - The. State
would need to draft improvement district regulations for Beach Management
Districts. The agency can be guided by recommendations in Chapter XI, as well

177

as improvement district regulations for Oahu, the Hawaii Community Development
Authority, and other coastal states such as Maryland, Rhode Island or North
Carolina. If the improvement district is established at the State level, legislative
approval would be required. The counties are currently set up to establish
improvement districts.

State Beach Fund - Legislative approval is required to establish a State Beach
Fund. Legislative language can be modeled after the 150-200 dedicated funds that
are established in the State. These funds cover topics from Agriculture, Airports,
the Aloha Tower, Anirnals,- Aquacu .Iture, Art,- Attorneys, and Bikeways .
to Underground Storage Tanks, Water Pollution, Water Supply and Workers
Compensation. Dedicated Funds have been established either in the state treasury
(e.g., Commerce and Consumer Affairs, Compliance Resolution Fund - HRS-26-9)
or within the administering Department itself (e.g. Leaking Underground Storage
Tank Fund - HRS-342L-51). Statutes on beach funds from other coastal states can
be used to provide additional guidance (see Chapter VII).

Beach. Enforcement Fund - If the State were to conduct enforcement activities,
then a Beach Enforcement Fund should be established at the State level.
Alternatively, the State Beach Fund could be used to support enforcement activities.
It would be the responsible State agency that could determine whether one or two
funds would be required after consideration of legal and administrative matters.

Shoreline Setback - A new shoreline setback would require legislative approval.
One to two years after the formation of a lead State agency, a bill for a new
shoreline setback could be submitted to the legislature. Before the submittal, the
State agency and counties would need to develop land use strategies that allow
buildable area to be preserved while increasing the shoreline setback. These
strategies would include a package of compensating zoning variances, a program
of Transferable Development Rights (TDR's), a new Shoreline Zone that can be
added to the State Land Use Classification scheme, or the use of an overlay district
to define areas exempt from specific zoning controls.

,Shoreline Transfer Tax - The Shoreline Transfer Tax would require fin-ther study
to address additional legal, administrative and economic issues. At the same time
that the shoreline transfer tax is studied, all other economic incentive and
disincentive strategies discussed in this report should be evaluated. Some shoreline
tax package could be passed one to two years after the formation of a State agency

178

responsible for Beach Management.

VoluntM Relocation - Within one to two years after the formation of a lead State
agency a report and bill could be sent to the legislature on establishing a voluntary
relocation program between the State and FEMA. This program would be
dependent on the amount of revenues in the State Beach Fund, which in turn,
depends on the implementation of a Shoreline Tax Package.

D. Interim Measures

The following measures can be implemented independent of'a beachfront
management program administered by a State agency.

1. State. The Office of State Planning, as lead agency for the Coastal Zone
Management Program, has the duty to monitor the activities of State and county
agencies to ensure that they adhere to the CZM objective and policies. It is
suggested that a new objective and policy be added to HRS-205A-2 that
specifically addresses the problem of beach loss and sea-level rise. This would
require a legislative amendment.

2. Counly. The following interim measures could be implemented at the
county level:

a. Overlay Districts. Overlay districts can be established that control the
types of erosion control structures along the shoreline (HRS-464). The county
could develop a specific erosion control design that is suitable to the conditions in
that district. By the use of an overlay district, a beach enforcement fund, and a
system of fines and subsidies, it is possible to convert from the use of seawalls, to
erosion control structures that fit the district design. Such a conversion can
temporarily recover a lost beach and, where appropriate, prepare the shoreline for
sand replenishment. For an overlay district to be formed on Oahu, it would
require an amendment to the Land Use Ordinance. This would also require review
by the City Planning Commission, the Department of Land Utilization, and the City
Council.

b. Improvement Districts. Improvement districts could be implemented at the
county level without the help of a State agency. The counties have the power,
-the State Enabling Act (HRS 46-1.5), to establish improvement districts.
through

179

On Oahu, the formation of an improvement district for beach improvements would
reguire an amendment to Oahu's Special Assessment Ordinance (City and County
of Honolulu, Revised Ordinances of Honolulu, Chqpter 24). In addition, the level
of landowner consent should be adjusted from the present level of 60%, to a highe
level, most likely 80-100%.

For an improvement district without State assistance, each of the counties
would have to provide their own technical and administrative staff to support
BMDs. It would be up to -the county to pursue Federal funding. Most likely, only
limited erosion control measures can be. implemented.. This may still be preferable
over the current options available to the individual landowner.

The county should investigate the possibility of using improvement districts
to help landowners convert legal and nonconforming vertical seawalls to buried
revetinents on private property. This would be a new twist on the improvement
district concept, since most districts are created to finance improvements on public
land that benefit the private party. Nevertheless, the language in Oahu's Special
Assessment Ordinance leaves open the possibility of forming improvement districts
for a valid public purpose.

Without State assistance, the cost allocation for improvements within a
district would need to be changed (the suggested allocation with a lead State
agency is - State 60-45%; Counties - 10%; and property owners 45-30%).
Furthermore, the landowner may have to pay a higher amount for an improvement
on their own property. After all the cost adjustments, a county improvement
district that converts seawalls to buried erosion control structures may not be
significantly different than the establishment of an overlay district with a system
of fines and subsidies.

c. Overlay versu s Improvement Districts. For implementation purposes, the
use of an overlay district, beach enforcement ftmd, and system of fines and
subsidies to convert seawalls to buried erosion control structures may be ideal
when: a) the landowners cannot cooperate; b) there are long, alternating stretches
of shoreline where seawall conversion may not be possible (e.g. there is'no room
to build a buried structure). The use of a county improvement district to convert
seawalls to buried structures may be preferable when coastal factors and strong
landowner cooperation allow a long stretch of shoreline to be converted from
seawalls to buried structures.

180

XIII. CONCLUSIONS

The formation and administration of Beach Management Districts involve
many complex issues such as cost allocation, sources of funding, viable erosion
mitigation measures, and landowner cooperation. Because of the complexities,
district formation will not occur by the initiative of landowners alone. The
experience in Hawaii, and other coastal states, is that landowners wouldrather act
on their own. Furthermore, the counties may not have the technical personnel to
organize a district, nor the.finances to create sufficient economic incentive. In the
study -of -beach districts for other coastal. states, it became. apparent that a
government agency is. needed to actively promote, coordinate and administer the
districts. Thus, the formation of a responsible State agency is recommended in
Hawaii. Once the agency is formed, it can not only establish BMDs, but could also
administer a statewide beachfront management program.

The problems associated with sea-level rise are serious. The response by the
State should be just as serious. Given an agency devoted to beach management,"
new ideas, technologies, and fimding schemes could be developed to restore or
preserve beaches within the district setting. For example, if the environmental
problems can be resolved, Kahala Beach could be restored at a relatively low cost
to the State, county and landowner. Such a project could -benefit all parties.
Similar projects may be possible, with some modification, at Ewa, Lanikai, Laniloa
and Portlock on Oahu; Waipoli Beach on Kauai; and Waimahaihai Beach on Maui.

Past efforts to address the coastal erosion problem have been blocked by
coastal landowners who have felt the government is intruding on private property
rights. In this study great efforts are made to address the concerns of the
landowner. Many of the programs in this report would be beneficial to both the
private property owner and the public. In Tables 10 to 14, the burdens and
offsetting benefits to each affected party are summarized. These summaries assume
all the proposals in this report are implemented.

The reaction to these programs by the public and the landowners remains to
be seen. Our initial discussion with landowners is that they would be receptive to
new programs to help them deal with coastal erosion and wave attack. Further
discussion is needed with various groups to modify, amend, refine or discard the
proposals in this report.

181

To the extent that the State, counties, landowners and public can cooperate,
great strides can be made to solve some of the predicted problems with sea-level
rise. Without cooperation, everybody will lose. If the State can find a way to
effectively balance the concerns of the public, the private sector, and the counties,
they should seize the opportunity. It may take increased administrative effort and
some financial commitment, but the investment would be well worthwhile.

182

Table 10 - Benefits and Burdens to the Owners of Developed Land

Benefits Burdens

A 1% to 2% reduction in real property A 2% property transfer tax is proposed on
assessments is proposed for beachfront the sale of a beachfront property. This tax
landowners who are in compliance with only applies to the buyer of the property,
coastal regulations. Such a reduction would not the present homeowner. The tax is to
benefit the long-term homeowner since they go into the State Beach Fund. The tax may
may receive a reduction in county property burden short-term landowners and
taxes every year. speculative purchasers..
Where it is feasible, the State and county A limitation would be placed on the.
would participate with homeowners in the construction of seawalls. Where hardening
construction of a Beach Management of the shoreline is required, buried
District, to provide long-term protection to structures such as revetments will be the
the coastal landowner, while preserving the shore protection of choice.
beach. The landowners fractional cost of
participation in a BMD may be less then
the full cost to construct a seawall or
revetment. Projects-within the BMD may
increase the value of coastal property.
The State or county may provide subsidies Fines would be placed on illegal seawalls.
to convert vertical seawalls to gently
sloping buried structures.

Money from the State Beach Recovery
Fund and FEMA may be available to give
landowners the option of moving off the
beach if they are threatened by erosion or
s rms. Landowners should view this
program as a form of financial protection.

183

Table I I - Benefits and Burdens to the Owners of Undeveloped Land

Benefits Burdens

The proposed Division-of State Beaches There is one additional office that the large
would provide technical assistance to the landowner or developer may have to deal
developer in dealing with erosion. The with.
Division would help the landowner in
obtaining the proper coastal permits for a
erosion control project. Through the use
of binding interagency agreements, master
application forms and perhaps one window
permitting; additional protection of the
shoreline is possible with less "red tape".

The Division of State Beaches would work In certain circumstances, the landowner
with the landowner to establish a suitable may have to conduct a coastal erosion
setback. Where previous studies are study to determine a suitable setback for
applicable, the coastal landowner may not their project.
need an additional study.

Buildable area is preserved for all shoreline, Shoreline setbacks are increased from 40
setbacks proposed. Where setbacks greater feet to 60 feet for new subdivisions and for
than 60 feet are needed to protect the land that is nonurban according to the State
beach, the counties could develop a Land Use classification scheme. On
package of compensating variances that eroding or unstable beaches, the shoreline
allow increased height, a smaller front or setback may be larger. In no case will be
side setback, or increased density. The net the setback be larger then necessary for the
effect is to preserve buildable area even State to protect the beach resource.
after the increased shoreline setback is
imposed. Another way to reduce the
economic burden includes a program of
transferable development rights on other
properties. The setback may be reduced for
pre-appro ed and pre-financed erosion
mitigation projects that preserve the
recreational beach.

184

Table 12 - Benefits and Burdens to the County

Benefit Burden

The residents of the county would benefit The county would pay 10% of the cost of a
from improved recreational use of the Beach Management District. The county
beach. Preservation of the beach helps to would provide a 1% to 2% reduction in
preserve the tourism industry for the real property assessments for beachfront
individual counties. homes that are in compliance with all
coastal regulations.
Improvements within a Beach Management
District may increase the value of
beachfront homes, thereby offsetting any
reduction in property tax revenues caused
by a 1-2% reduction in real property
assessments.

When narrow strips of private land are
makai of county infrastructure, the county
benefits by a Joint State-county-landowner
erosion control project that protects the
landowner from erosion.

The county would receive technical, and
financial assistance by the State in dealing
with coastal erosion. This assistance may
become critical if the current rate of sea
level rise were to accelerate.

185

Table 13 - Benefits. and Burdens to the State

Benefit Burden

Preservation of beaches by the State Legislative appropriations will be needed to
protects a key attraction of visitors to the establish the Division of State Beaches and
islands. Thus the number one industry in to fund the State Beach Fund. The State
the State, tourism, benefits. would pay 60% to 45% of a Beach
Management District.

Protection of beaches fulfills the State duty Greater administrative effort is required of
as trustee of coastal resources. the State.

Revenue for improvement projects can be
derived from landowner, county and
Federal contributions. Significant revenues
are also possible from a shoreline transfer.
tax.

T e comprehensive plan presented in this
report would help to mitigate the serious
problems associated with rising sea-level.

Table 14 - Benefits and Burden to the Public
Benefit I Burden

Some beaches that were lost may be Some taxpayer money would be needed to
returned to the public. Beaches that are restore and preserve beaches.
presently threatened can be preserved.

By preserving or restoring beaches, the
scenic beauty and recreational value of the
coastline is protected for future generations
in the State.

Preservation of beaches is required to
protect the tourism industry, from which all
members of the public benefit.

186

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