Folly Beach, South Carolina survey report on beach erosion control & hurricane protection

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

Coastal Zone
information
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,'~,:N �' ~SOUTH CAROLINA
SURVEY REPORIT
ON BEACH EROSION CONTROL/
& HURRICANE PROTECTION

Property of CSC Library

C _ U.S. ARMY ENGINFEER DISTRICT, CHARLESTON

CORPS OF ENGINEERS

,9. . \ ~Charleston, South Carolina

: ' SUBMITTED:

4 5 9 . 4 AUGUST 1979
1979
1979 ]IC

Syllabus

The purpose of this beach erosion and hurricane protection study
was to investigate the 6.2 miles of Folly Island ocean beaches in order
to determine the extent of damages by erosion of the shoreline and to
develop the most suitable plan for the protection of this beach.

Folly Island beach is subject to severe damage from wave attack
during hurricanes and during northeasters. The former generally occur
during the months of July through October but are infrequent events.
The latter occur during the months of October through April with each
season producing one or more significant events.

The best solution was determined to be a structural plan for
beach development in combination with non-structural measures that
have been established in the study area. The most practicable struc-
tural plan consists of a beach berm having a width of 25 feet at an
elevation of four feet above mean sea level and a gradually sloping
beach face to provide a combined recreational beach width of 61 feet
at the time of placement. Based on historical erosion rates, the
recreational beach width would average 50 feet between renourishment
periods. The prospective beach would be maintained by periodic sand
renourishment every five years. The estimated total first cost of the
improvement is $2,393,000. The total annual cost, including interest
and amortization, is estimated at $396,300.

It is therefore recommended that, subject to certain conditions
of non-Federal cooperation, the foregoing plan of improvement be adopted
as a Federal project, at a presently estimated first cost to the United
States of'$722,500 with an annual periodic beach renourishment cost to the
United States of $85,200. Non-Federal costs are estimated at $1,670,500
for plan implementation and $136,700 annually for periodic sand replacement.

Rev.
28 Mar 80

FOLLY BEACH, SOUTH CAROLINA
FEASIBILITY REPORT
FOR BEACH EROSION CONTROL AND
HURRICANE PROTECTION

TABLE OF CONTENTS
ITEM PAGE'
THE STUDY AND REPORT 1
PURPOSE AND AUTHORITY 1
SCOPE OF THE STUDY 2
STUDY RARTICIPANTS AND COORDINATION 2
THE REPORT 3
PRIOR STUDIES AND REPORTS

RESOURCES AND ECONOMY OF THE STUDY AREA 5
DEVELOPMENT AND ECONOMY 6
ENVIRONMENTAL SETTING AND NATURAL RESOURCES S
HUMAN RESOURCES 10
LAND USE ANALYSES 11

PROBLEMS AND NEEDS 12
PRIOR CORRECTIVE ACTIONS AND EXISTING 12
STRUCTURES
THE CONTINUING PROBLEM 13
IMPROVEMENTS DESIRED 15

FORMULATING A PLAN 17
FORMULATION AND EVALUATION CRITERIA 17
POSSIBLE SOLUTIONS 20
PLANS CONSIDERED FURTHER 20

SELECTING A PLAN 23
BASIS FOR SELECTION 23
IDENTIFICATION OF "NED" AND "EQ" PLANS 24
SELECTING PROCESS 25
THE SELECTED PLAN 26

TABLE OF CONTENTS (CONT'D)

ITEM PAGE

THE SELECTED PLAN 26
DESCRIPTION 26
PLAN ACCOMPLISHMENT 27
ENVIRONMENTAL EFFECTS 28
CONSTRUCTION 29
OPERATION AND MAINTENANCE 29

ECONOMICS AND SELECTED PLAN 29
METHODOLOGY 29
ESTIMATED FIRST COSTS 30
PERIODIC RENOURISHMENT COSTS 31
ANNUAL COSTS 31
BENEFITS 32
BENEFIT-COST RATIO 33

DIVISION OF PLAN RESPONSIBILITY 33
COST APPORTIONMENT 34.
FEDERAL RESPONSIBILITIES 36
NON-FEDERAL RESPONSIBILITIES 36

PLAN IMPLEMENTATION 36

VIEWS OF NON-FEDERAL INTEREST 38

REVIEW BY OTHER FEDERAL AGENCIES 38

STATEMENT OF FINDING 30o

RECOMMENDATIONS L!O0

TABLE OF CONTENTS (CONT'D)
~~~~. . .... . . . .
LIST OF FIGURES

NO. TITLE FOLLOWING PAGE

1 SOUTHWEST OF. PAVILION (fI JULY 1972) 10

2 FOLLY BEACH BUSINESS DISTRICT AND 12
RECREATIONAL PAVILION AREA

3 DAMAGE FROM HURRICANE GRACIE - 12
SEPTEMBER 1959

4 ENCROACHMENT OF THE OCEAN - 12
30 JANUARY 1978

5 ENDANGERED ACCESS - JANUARY 1978 12

6 DUNE EROSION -JANUARY 1978 12

7 TIMBER AND ROCK GROINS .4

8 ROCK AND RIPRAP REVETMENT 14

9 CONCRETE SEAWALL 1

10 TIMBER SEAWALLS 14

11 ALTERNATIVE BEACH DEVELOPMENT AND BEACH 22
AND DUNE DEVELOPMENT LOCATIONS

12 TYPICAL SECTIONS OF CONSIDERED PLANS AT 22
FOLLY BEACH, SC.

TABLE OF CONTENTS (CONT'D)

LIST OF TABLES

NO, TITLE FOLLOWING PAGE

1 POPULATION, INCOME AND EMPLOYMENT FOR 10
CHARLESTON SMSA INCLUDING BERKELEY,
CHARLESTON AND DORCHESTER COUNTIES

2 SUMMARY OF ALTERNATIVES 20

3 SUMMARY OF BEACH DEVELOPMENT AND BEACH 22
AND DUNE DEVELOPMENT PLANS

4 COMPARISON OF COSTS AND BENEFITS 23

5 SYSTEM OF ACCOUNTS 2L1

6 SUMMARY OF COST APPORTIONMENT 25

7 ESTIMATED FIRST COSTS OF SELECTED PLAN 30

8 ESTIMATED RENOURISHMENT COSTS FEDERAL AND 30
NON-FEDERAL (5-YEAR PERIODS)

9 ESTIMATED AVERAGE ANNUAL CHARGES 31

10 MONETARY BENEFITS 32

11 COST APPORTIONMENT FOR SELECTED PLAN 35

12 SUMMARY SYSTEM OF ACCOUNTS 39

TABLE OF CONTENTS (CONT'D)

LIST OF FIGURES

NO. TITLE FOLLOWING PAGE

1 SOUTHWEST OF PAVILION (L JULY 1972) 10

2 FOLLY BEACH BUSINESS DISTRICT AND 12
RECREATIONAL PAVILION AREA

3 DAMAGE FROM HURRICANE GRACIE - 12
SEPTEMBER 1959

4 ENCROACHMENT OF THE OCEAN - 12
30 JANUARY 1978

5 ENDANGERED ACCESS - JANUARY 1978 12

6 DUNE EROSION - JANUARY 1978 12

7 TIMBERAND ROCK GROINS 1.L

8 ROCK AND RIPRAP REVETMENT 14

9 CONCRETE SEAWALL 11.

10 TIMBER SEAWALLS 14

11 ALTERNATIVE BEACH DEVELOPMENT AND BEACH 22
AND DUNE DEVELOPMENT LOCATIONS

12 TYPICAL SECTIONS OF CONSIDERED PLANS AT 22
FOLLY BEACH, S.C.

TABLE OF CONTENTS (CONT'D)

LIST OF TABLES

NO. TITLE FOLLOWING PAGE

1 POPULATION, INCOME AND EMPLOYMENT FOR 10
CHARLESTON SMSA INCLUDING BERKELEY,
CHARLESTON AND DORCHESTER COUNTIES

2 SUMMARY OF ALTERNATIVES 20

3 SUMMARY OF BEACH DEVELOPMENT AND BEACH 22
AND DUNE DEVELOPMENT PLANS

4 COMPARISON OF COSTS AND BENEFITS 23

5 SYSTEM OF ACCOUNTS 211

6 SUMMARY OF COST APPORTIONMENT 25

7 ESTIMATED FIRST COSTS OF SELECTED PLAN 30

8 ESTIMATED RENOURISHMENT COSTS FEDERAL AND 30
NON-FEDERAL (5-YEAR PERIODS)

9 ESTIMATED AVERAGE"ANNUAL CHARGES 31

10 MONETARY BENEFITS 32

11 COST APPORTIONMENT FOR SELECTED PLAN 35

12 SUMMARY SYSTEM OF ACCOUNTS 39

TABLE OF CONTENTS (CONT'D)

LIST OF PLATES

NO , TITLE FOLLOWING PAGE

1 GENERAL MAP 41

PREDICTED 50-YEAR SHORELINE 41

2 SHEET 1 OF 5 41

3 SHEET 2 OF 5 41

4 SHEET 3 OF 5 41

5 SHEET 4 OF 5 41

6 SHEET 5 OF 5 41

7 PLAN OF IMPROVEMENT 41

LIST OF APPENDICES

No. TITLE

1 TECHNICAL REPORT

2 ENVIRONMENTAL IMPACT STATEMENT

3 PERTINENT CORRESPONDENCE

4 SECTION 404(B) EVALUATION FOR THE
RESTORATION AND NOURISHMENT OF
FOLLY BEACH, S.C.

FOLLY BEACH, SOUTH CAROLINA

FEASIBILITY REPORT
FOR BEACH EROSION CONTROL AND
HURRICANE PORTECTION

The Study A nd Report

Water areas have special appeal to man and contribute greatly
to his pleasure.' To many along the Atlantic shore, the beach is the
place to go for a refreshing swim, sunbathing, or a walk along the
strand. Much of the relaxation needed for today's high-tempo living
is furnished by ocean beach areas. However, beautiful sandy beaches
adjacent to the ocean are generally limited from standpoints of
availability and width, and these relatively narrow beaches are subject
to erosion by wave action. Apart from this, human misery and damage
to property are often companions of storms which buffet the coast-
line. These factors of coastal erosion and structural storm damage are
present to an important degree in the Atlantic Coast resort area
of Folly Beach, South Carolina.

PURPOSE AND AUTHORITY

The purpose of this study is to evaluate the problems with.
respect to beach erosion at Folly Beach and its vulnerability to
storm damage; to investigate the various structural and non-structural
alternatives; to determine cost sharing between the Federal Govern-
ment and local interests; and to select and recommend the best course
of action to remedy the problems.

The study was requested by local interest through their represen-
0 ~~~~tatives in Congress. Recognizing the above problems and the economic

and aesthetic importance of ocean beaches, the Committee on Public
Works of the Senate adopted a resolution on 15 June 1972 requesting
that the Secretary of Army direct the Chief of Engineers to make such
a study of Folly Beach and vicinity.

SCOPE OF STUDY

The study is focused on the six miles of Folly Island coastline in
Charleston County, South Carolina. The location of Folly Island is
shown on Plate 1. Investigations were made of the area to determine
damages, either by erosion of the coastline or by storm tides and
waves; measures for protecting the area or preventing the damages; the
accompanying costs and benefits; the selection of the most feasible
plan; and related matters, including coordination with concerned agen-
cies and the public. The studies were made in the depth and detail
needed to permit plan selection and to establish its feasibility.

STUDY PARTICIPANTS AND COORDINATION

The District Engineer coordinated the study with appropriate
Federal, State, and local agencies. This office requested and received
comments concerning problem identification and possible solutions
from such agencies as U. S. Fish and Wildlife Service; National
Park Service; U. S. Coast Guard; U. S. Environmental Protection
Agency; U. S. Public Health Service; National Oceanic and Atmos-
pheric Administration; South Carolina Wildlife and Marine Resources
Department; S.C. Highway Department; S.C. Department of Parks, Recre-
ation, and Tourism; and Charleston County Park, Recreation, and Tourist
Commission. Several local environmental groups also participated in
the study. Moreover, public meetings were held on 8 April 1976,
29 November 1977, and 7 December 1978 to afford interested parties
and the general public an opportunity to express their views concerning
the improvements desired and the need and advisability of their
execution.

THE REPORT

In the interest of clarity of presentation and reference, the
report has been arranged into a main report with four appendices.

The main report is a general non-technical presentation giving
the results of the feasibility study. It presents a broad view of the
overall study for the benefit of both general and technical readers.
Included are a description of the study area; the problems and needs
for protective measures; formulation of a plan for meeting these needs;
a summary of project economics indicating the benefits, costs, and
justification; the division of project responsibility between Federal
and non-Federal interests; a summary of environmental, social and
economic effect assessment; and recommendations for implementing the
selected plan. Maps showing general locations (Plate 1), predicted
50-year shorelines (Plates 2 through 6) and the recommended plan
(Plate 7) are inclosed at the end of the Main Report.

The four appendices to the report present supporting data and
details covering the features of the feasibility report:

Appendix I is a technical report with all basic data needed to
support conclusions made in the Phase I Report. This appendix has
the same general outline as the formulation and evaluation part of
the main report, but in greater detail. It is the key document for
the technical reviewer.

Appendix 2 contains the Environmental Impact Statement.

Appendix 3 contains all pertinent correspondence in connection
with the study, including comments from interested agencies.

Appendix 4 contains a reference list for coordination as required
by Section 404 of Public Law 92-500.

3 ~~~~~~~~~~Rev.
6 Nov 79

PRIOR STUDIES AND REPORTS

In 1935, a beach erosion report on Folly Beach was submitted by
the Beach Erosion Board (renamed Coastal Engineering Research Center)
in cooperation with the Sanitary and Drainage Commission of Charleston
County. In this report, the Board proposed three methods of protection
but refrained from making any recormmendation as to the adoption of any
specific one of the methods given, as it was considered that the selec-
tion must necessarily be made by local interests. The problem area
at that time was on the southwestern portion of Folly Island where
storms of September 1933 and May 1934 destroyed the first row of houses.
The proposed plans were:

Plan A - Restoration of eroding beaches;
Plan B - Construction of bulkheads and groins; and
Plan C - Beach restoration with groin construction.

All of the cost of these improvements were to be paid for by
local interests.

A study of Charleston Harbor Jetties, 1935, was done by the
Charleston District, U.S. Army Corps of Engineers, to become a part
of the Shore Protection Board, OCE report entitled "Report on Jetties,"
The study was made to determine the effect of the Charleston Harbor
jetties on adjacent shorelines. Concluded from these studies is that
usually the effect of the jetties extend only about one mile above and
below the jetties. Folly Beach is about six miles southwest of the
Charleston Harbor jetties.

An appraisal report, Investigation on Hurricanes and Associated
Problems Along the South Carolina Coast, was prepa~3ed by the U.S. Army
.Corps of Engineers, office of the District Engineer, Charleston, S.C.
It was submitted in January 1957 and approved July 1957. The investi-
gation indicated the need for further study and report with a view

toward effecting protective measures for minimizing loss of human
life, damage to property and health hazards, and for improving
hurricane forecast and warning services.

A hurricane survey interim report on Folly Beach was printed as
House Document No. 302, 89th Congress, 1st Session, on 7 October 1965.
It was concluded in this report that protective works to prevent hur-
ricane damage were not economically justified.

In 1968, the U.S. Army Corps of Engineers, Charleston District,
completed the Folly Beach Detail Project Report on Beach Erosion
Control. This report evaluated a pr-oblem reach on the northeastern
end of Folly Beach, known locally as East Folly Shores. This one-
half-mile reach immediately downcoast from the United States Coast
Guard Loran Station-, was'recommended for a Federal small beach
nourishment project. A tentatively recommended project called for
initial placement of a five-year supply of sand or about 45,500 cubic
yards at an estimated first cost (1967 dollars) of $52,000. Costs
were to be shared with 55 percent being allocated to a non-Federal
sponsor and 45 percent to the Federal Government. The project was
economically feasible but the local sponsor (Folly Beach Township
Commission) was unable to provide the items of local cooperation.

A Beach Erosion Inventory of Charleston County, South Carolina
report was written by the University of South Carolina and printed in
March 1975 as the South Carolina Sea Grant Technical Report Number 4.
It provides a preliminary summary of beach erosional-depositional
trends for Charleston County. These trends were measured from sequen-
tial vertical aerial photographs covering the period 1939 to 1973.
The report states that Folly Beach is primarily dominated by erosional
trends.

Resources And Economy of Study Area

A general understanding of the resources and development trends
of the study area is helpful in identifying its problems and needs
* ~~~and formulating the various solutions thereto.

DEVELOPMENT AND ECONOMY

Charleston County has a well diversified economy. The principal
economic activities of the area can be related to the availability of
several natural resources. A temperate climate, along with favorable
topography and soil conditions are conducive to both agriculture and
silviculture, which'are engaged heavily in the county and account for
the greatest land use. A coastal location with several navigable rivers
makes Charleston a favorable place for import/export shipping and re-
lated port and terminal activities. The South Carolina Ports Authority
is presently planning further port facilities in hopes of improving the
economic development of the county and the state.

Also, attributable to the geographical and geological situation of
Charleston County are several military and government installations,
including Air Force and Navy Bases, which employ a large sector (approxi-
mately one-third) of the work force in the area. The coastal location
also affords opportunities for area residents in several fisheries, both
commercial and recreational, including shrimping, finfishing, oystering,
clamming and crabbing. The historical background and fine architecture
of Charleston, in addition to the beauty and aesthetic appeal of the
Lowcountry's beaches, marshes and rivers, combine to make Charleston
extremely popular with tourists. Tourism, recreation, and associated
services provide 12,000 jobs and 45 million dollars per year in personal
income to residents of the Charleston area. In fact, tourism-related
employment is second only to Government employment within the county.
In the immediate vicinity of Folly Island, which is located in Charleston
County about 10 miles south of the City of Charleston, recreation, tourism
and fisheries are of primary importance, both in terms of income and local
empl oyment.

Folly Island-is the second island south of the entrance channel
to Charleston Harbor and is typical of barrier islands. (See Plate 7
which is located at the end of this main report.) Its alignment

6 Rev
6 Nov 79

is from northeast to southwest. Bounded on the northeast end by Light-
house Inlet, on the east by the Atlantic Ocean, on the southwest end by
Stono River, and on the northwest side by Folly River, the island is
approximately six miles long and at the widest part is about one-half
mile across., A comparatively flat beach of fine sand fronts the ocean
side. The mean tide range is 5.2 feet and spring tide range is 6.1
feet. Along the developed sections, immediately shoreward of the sandy
beach, elevations range from 6 to 15 feet above mean sea level. Access
to the island from peninsular Charleston is by S.C. Highway No. 171
with six bridge crossings, two of which are drawbridges.

The resort development extends along the ocean side of the island
for a distance of 4-.9 miles (see Plates 2 through 6). A U.S. Coast
Guard Loran Station is located at the northeastern end of the island,
and at the southwestern end a narrow spit extends about 0.7 mile down-
coast of existing development. This latter reach, known as the Bird
Key Area, is being considered for development by a number of investors.

Considerable marsh area adjoins Folly River along the northern
half of the island, and palmetto, pine, and deciduous growth abound
on higher ground. The development of Folly Island began about 1920,
and is a typical seashore development, having mostly frame buildings
consisting principally of cottages, homes, concessions, and small
shops. An amusement park and a fishing pier are located on the island
near the center of the beach. All of the island is in private owner-
ship except for about 32 acres on which the Loran Station of the U.S.
Coast Guard is located.

Charleston County beaches are heavily used by Charleston residents.
Folly Beach, which draws about 60 percent of its day-users from Charleston
County, is widely regarded to be more of a public beach than the
county's other~beaches. Isle of Palms and Sullivan's Island to the
north and Kiawah Island and Seabrook Island below Folly Island are the
other developed beaches in the county. Kiawah and Seabrook Islands are
essentially restricted to the public. Public parking space is very

limited on Isle of Palms and Sullivan's Island. Folly Beach's proximity
to the City of Charleston makes it a prime recreation area, despite an
eroding beach and lack of existing facilities such as parking and com-
fort stations.

ENVIRONMENTAL SETTING AND NATURAL RESOURCES

Charleston County is at the center of what is known locally as the
Carolina Lowcountry. The name fits. Elevations are typically less
than twenty feet above mean sea level and relief is extremely limited.
The study area lies on the lower coastal plain bordering the Atlantic
Ocean and was once a submerged portion of the Continental Shelf. The
coastline in this region is-composed of a chain of barrier islands;
these islands are usually between two and ten miles long and often less
than one mile wide. They are fronted by gently sloped sandy beaches on
the seaward side of the island and backed by vast expanses of extremely
productive salt marsh. Folly Island is one of more than a dozen such
islands in Charleston County. Separating'these islands from each other
are broad tidal rivers (such as the Stono River) which drain the in-
terior. Tributary to these major rivers, flowing laterally between the
islands and the mainland, are series of denidritic tidal creeks which
alternately flood and drain the marshes. Folly River is the main artery
for such a system of creeks located behind Folly Island, and Lighthouse
Creek is a small tidal stream at the western end of the island. As
one proceeds inland, the larger estuaries taper into meandering brack-
ish rivers penetrating into low wooded lots and farmland. Continuing
further upstream, relief increases gradually. At some locations in
the interior of the county, there are small series of rolling hills,
which are relics of beach dunes from previous stands of the sea.

The geologic formations of the Coastal Plain Provinces are com-
prised of layers of unconsolidated sands and gravels underlain by
layers of barns, clays and marls of different ages, all lying nearly
horizontal. Soil borings in Folly River, Stono Inlet at the west

end of the island, and Lighthouse Inlet at the east end produced fine
silty sand to a depth of about 20 feet below mean low water, with silt
content increasing as the distance from the ocean increased. $coop
samples were taken from the dry beach and to minus nine feet, mean low
water, in the ocean off Folly Beach; the material was generally found
to be fine clean sand with a high shell content. Analyses of these
materials are included in Appendix 1.

The climate of the Lowcoun try's barrier islands is marine sub-
tropical. The mean average annual temperature near Folly Island is
660F. with an average high temperature in July of 81 OF. and an average
low of 490F.~ in February. Relative humidity in the area is around 75
percent, but the discomforting effect of this high humidity is moderated
by an afternoon sea breeze. Precipitation occurs chiefly as rainfall,
averages about 50 inches per year, and is fairly well distributed through-
out the year. Between dawn and dusk, the sun shines an average of 65 per-
cent of the time in Charleston during the year, but during May and Septem-
ber may be seen as much as 90 percent of the time. These conditions
provide Charleston County with a relatively long growing season of 295
days per year. These conditions further allow human comfort the year
round and provide a situation that is well suited for outdoor recreation
and tourism.

There are some 4,000 acres of salt marsh in the immediate planning
area. These wetland areas play a very important role in the ecology of
the area, providing habitat for waterfowl, nursery areas for ~juvenile
stages of many important species of fish and shellfish, water quality
improvement, and primary biological production which supports a host of
marine life in adjacent coastal waters.

There are public oyster grounds and private leases for oysters and
clams in the planning area. Crabbers also fish Folly and Stono Rivers
extensively. Shrimp are taken recreationally. The area is a favorite
among local fishermen who catch many different species of fish in and
* ~~~around this estuary.

In short, the major natural resources of the study area are: a
temperate climate; topography and soils conducive to agriculture and
silviculture (which are important to the county but of little signifi-
cance within the immediate planning area); geological features such as a
coastal location with sheltered high ground areas having access to the
ocean via navigable rivers; an ocean itself which harbors an abundance
of biological and mineral resources; long stretches of gently sloped
beaches for walking and bathing; and a vast expanse of extremely pro-
ductive salt marshes which serve as nursery areas for a variety of marine
organisms and in turn support large commercial and recreational fisheries.

HUMAN RESOURCES

Historically, Charleston County has been the most populous county
in the state. However, in the past decade both Richland and Spartan-
burg Counties in the upcountry have come to be about equal in population
to that of Charleston County.

The population in Charleston County has grown from 216,382 in 1960
to 247,565 in 1970 and 262,400 in 1975. This population is expected to
reach 271,000 by 1980. At the same time, the population of James Island
has grown from 13,872 in 1960 to 24,197 in 1970, 25,525 in 1975 and is
expected to reach 28,090 in 1980. The population of Folly Island has
been more stable. In 1960, there were 1,137 permanent residents in the
Township of Folly Beach; in 1970, there were 1,157 persons and in 1975,
the population was 1,500. An indication of historical and projected
future growth in population, per capita income, and employment in the
study area is given in Table 1.

It is estimated that Folly Island's resident population increases
to about 4,500 persons during the summer months and on peak days visitors
to this island may exceed 30,000. Figure I shows high usage being made
of the beach during the 4th of July holiday in 1972. Erosion along most of
Folly Island has severely hampered the development of this resort.

TABLE 1

Population, Income and Employment for Charleston SMSA
including
Berkeley, Charleston and Dorchester Counties-/

YEAR
ITEM 1959 1970 1980 1990 2000 2010 2020 2030

Population 274,909. 336,837 389,000 421,000 457,000 477,500 497,500 515,200

Total Personal Income
(Thousands of 1967 Dollars) 451,033 909,500 1,487,000 2,121,400 3,114 700 4,358,100 5,775,200 7,475,000

Per capita income (1967 $) 1,641 2,700 3,825 5,039 6,808 9,127 11,608 14,510

Total Employment 94,533 127,950 161?800 175,500 196,900 210,900 213,500 221,500

Employment/Population Ratio 0.34 0.38 0.42 0,42 0.43 0.44 0.43 0.43

Total Earnings .388,437 784,130 1,252,400 1,745,900 2,518,900 3,485,600 4,586,700 5,905,600

Government 159,244 347,346 517,200 710,600 1,012,600 1,380,000 1,839,300 2,362,200

Manufacturing 59,228 121,892 205,400 284,600 395,500 526,300 644,000 767,700

Wholesale & Retail Trade 57,343 102,107 161,500 218,200 306,600 414,800 527,500 649,600

Services 41,924 86,284 170,300 263,600 418,600 637,900 892,600 1,240,176

1/ From projections Economic Activity in South Carolina, Series E Population, December 1975, SADPD-75-1.

SOUTHWEST OF PAVILION
4 JULY 1972

LAND USE ANALYSIS

Only a small percentage of lanhdw;ithin te immediate planning area
is above mean high water. The predomifnant-u-se of high ground areas
is for low density residential purposes. With''the Town of Folly Beach,
which incorporates all of the island:, X -the-re~ a're approximately 1,500 acres
of land, half of which is marsh land.,'.Of'ithe remaining 750 acres of high
ground, 327' acres remain undeveloped, : ng about 420 acres of developed
land. Residential properties occupy 20 cres or about half the presently
developed land. There are 1,329g:housig units at Folly Beach; most (80%)
are single family cottages. Ref!ecting t resort nature of this shore
community, only one-third of these e :occupied on a year-round
basis. , '

The second largest category of'land;':use on Folly Island is trans-
portation rights-of-way. The town has:a:rioadnet that occupies 120 acres
of land. There are presently about 325 off-street parking spaces not
including private driveways.

Commercial properties occupy only4about 20 acres and consist mostly
of retail establishments, such as grocerylstores, filling stations,
restaurants and arcades located in the center of the island.

Some eight acres of this beach frot' area including the existing
boardwalk and fishing pier has been bought by a church group and
they are developing it into a family recreational area open to the
general public. Tennis and basketball courts, a swimming pool and
waterslide will be built. Existing public facilities, including
bath houses, comfort stations and parking spaces are being expanded.

On the northeast end of the island,'the U.S. Coast Guard occupies
32 acres from which it operates electoi'nic aids to navigation. The south-
west end of the island is presently undeveloped. This 55-acre parcel is
a narrow recurved spit which consists ;of'a-�mile long primary and secondary
dune system backed by salt marsh and the Folly River. Southwest of this

~~~~~~?11 ,,

end of Folly Island, across a series of sand flats, lies an extremely
small island, Bird Key, which serves as a rookery for several species of
shorebirds.

Problems And 1Needs

In general, the citizens of the Town of.Folly Beach want to pre-
serve the small town atmosphere offered by the community while improv-
ing the quality of life of its citizens. This envisions increased
employment opportunities, increased property values, and development of
a tax base sufficient to support desired services. Realization of these
objectives will only be achieved after a proper solution is effected to
deal with the destruction wrought by ocean waves.

Stabilization of the shore is needed to protect existing and future
development against damage from erosion and to insure the availability
of adequate beach for recreational use. Encroachment of the ocean has
destroyed both private and public works along most of the ocean shore-
line. Homes, roads, erosion control structures, and valuable beachfront
lands have suffered severely. Much of the dry beach area also has been
lost in recent years.

PRIOR CORRECTIVE ACTIONS AND EXISTING STRUCTURES

On the northeast end of Folly Island, at the Loran Station, the
U.S. Coast Guard has constructed a combination groin-retaining wall
structure which apparently has significantly reduced erosion at that
site. The timber wall and much of the six timber and rock groins have
been covered with sand, and vegetation is migrating oceanward beyond
the wall along most of this reach. Coast Guard stabilization structures
consist of a timber seawall% around the east end of the island from which
six groins spring oceanward, and a combination training breakwater struc-
ture composed of segments of stone and of fabric sandbags on the inlet
side. Photographs of these structures are displayed in Attachment C-2
of Appendix 1.
12 Rev
6 Nov 79

FOLLY BEACH BUSINESS DISTRICT

RECREATIONAL PAVILION AREA

FIGURE 2

DAMAGE FROM HURRICANE GRACIE
29 SEPTEMBER 1959

FIGURE 3

ENCROACHMENT OF THE OCEAN
30 JANUARY 1978

FIGURE 4

4~~~~~EDAGRDACS

4~~~~~AUR 197

FIGR

DUNE EROSION
JANUARY 1978

FIGURE 6

The South Carolina Highway Department has constructed and is main-
taining 41 timber and rock groins along the developed coastline of Folly
Beach from the Loran Station to the northeast to within about 4,000 feet
of the southwest end of the island. Photographs of these structures are
shown on Figure 7 and their locations may be seen on Plates 2 through 6.
A rock revetment approximately 1,200 feet long has also been constructed
between Groins 16 and 18 where erosion narrowed the island to the point
that a breakthrough might occur, severing the northeast end from the
remainder of the island. This revetment is shown in the top picture of
Figure 8 and on the right side of Plate 2.

Beachfront property owners are using many different type structures
to protect their property. These include: concrete sheetpile, asbestos
corrugated sheetpile, timber seawalls, rock revetment, rubber tire walls,
sand-fencing, and one property owner is experimenting with concrete block
breakwaters constructed just oceanward of the mean high water line. Some
of these structures are shown in Figures 8 through 10. Property owners
have had varying degrees of success with their erosion control efforts.
One problem stems from the piecemeal way in which these structures are
constructed. Some property owners are unable or unwilling to attempt to
control the erosion of their property while others cannot agree with their
neighbors on a best "solution". The City of Folly Beach is attempting to
organize beachfront property owners so that an integrated erosion control
system can be constructed. Currently, they are seeking state and county
help in constructing a continuous seawall and placing approximately
700,000 cubic yards of sand on 22,000 linear feet of ocean shoreline.
The City plans to use the same borrow areas that are considered for use in
the Federal project. Such a project would only serve as a stop-gap measure
for the preservation of high ground until such time as a more permanent
solution is effected through Federal programs.

THE CONTINUING PROBLEM

Future Shoreline Positions. To gain insight into the future,
historical shoreline change rates measured at the seven selected
locations on Folly Island were used to predict future positions of the
shoreline. Possibilities were plotted on the January 1977 aerial photo-
graphs (Plates 2 through 6) so that the hazards to development, existing

13 Rev' 7

at that time, could be reasonably determined. Both the long term rates
(based on 128 years of record - 1849 to 1977) and short term rates (based
on 22 years of record - 1955 to 1977) are displayed. Since beach restora-
tion and nourishment would more nearly simulate the natural beach, the
long term erosion rate is considered more applicable to determine annual
nourishment requirement. The man-made structures which have greatly
influenced the short term erosion rate would be mostly covered by the
beach fill.

Beach Problems. Had there been no efforts to control the erosion
at Folly Beach, the condition of the beach in the future would be es-
sentially the same as it has been in the past. Man, in his attempts to
hold the high land, has placed artificial barriers to the erosive energy
of incoming waves. These structures have at best resulted in a temporary
solution to the problem they were meant to solve; however, the erosion of
the beach strand and berm goes on, often at an accelerated rate because
of the reflective nature of corrective structures. As the beach con-
tinues to erode, less and less area is available for recreational use
while foundations supporting protective structures become more and more
exposed to the forces of the ocean. For that mat ter, the whole struc-
tures' exposure increases as the erosion continues.

With the passage of time, many of the structures will fail from the
piping of materials from behind. This process is apparent at the
Pavilion area seawall. The beach fronting this wall has been lowered
by erosion to such an extent that cracks in the construction joints, which
are not sand tight, are exposed to pulsating hydraulic forces for a
considerable portion of the normal tide cycle. Sand has piped out through
these cracks and failures are apparent in the concrete slab walks which
are supported on wall backfill.

Should this piping be allowed to continue, all of the backfill,
which resists the overturning forces of the sea as well as serving as
a base for walks and some of the buildings, will ultimately pipe away.

14 Rev
6 Nov 79

~ ~!!~~~~~~~~~~~~~~~~~~~~~~~~Iki iiiii

TIMBER AND ROCK GROINS

FIGURE 7

r _:::: ::: :: of

ROCK AND RIP RAP REVETMENT

FIGURE 8

CONCRETE SEAWALLS

EO~ ~~~~~ i ~~FIGURE 9

TIMBER SEAWALLS

FIGURE 10

When this happens, the wall will probably fall, leaving an exposed head-
land. This will erode at an accelerated rate until that segment of
shore better conforms to the alignment updrift and downdrift. Proof of
this geomorphic phenomenon is shown in photographs of lesser private
structures along the beach (see Figure 10 which precedes this page).

Failure of protective structures allows nature to create a higher
and wider beach than that normally found fronting such structures before
failure. This', of course, is achieved with a loss of high land and of
the appurtenances constructed thereon.

IMPROVEMENTS DESIRED

During the course of this study, individuals and groups were
afforded many opportunities to express their desires concerning cor-
rective works for hurricane surge and shore erosion problems. Three
formal public meetings were held to afford the general public a struc-
tured opportunity for participation in accomplishing the tasks which
had to be performed in the formulation of a solution to these problems.
These meetings were held in March 1976, November 1977 and December 1978.
Viewpoints varied,,widely depending upon the hazard to one's property,
pocketbook, and/or one's recreational opportunities. Four distinct
perspectives were apparent. These were classed as the Back Island
Citizen, Front Beach Owner,�Visiting Day User, and Dynamite Hole View-
points.

Back Island Citizen's Viewpoint. In general, the back island
citizens selected the Town of Folly Beach as their place of residence
because it is-widely separated from the nearby larger community and
offers an opportunity for -an independent life style. These citizens
would like to see the erosion stopped and hurricane damage to improve-
ments prevented, but will not tolerate a significant increase in their
tax liability.

Front Beach Owner Viewpoint. Front beach property owners are
interested mainly in preserving their land and the appurtenances con-
structed thereon. As far as the beach strand is concerned, this special
interest group would be satisfied with enough beach to meet their per-
sonal needs and the needs of those who rent their cottages and apartments.
Recognizing that the opportunity for Federal assistance along private
shores is contingent upon public use, this group is willing to encourage
widespread public use of the beach. Merchants in the business district
also support widespread usage of the beach as a means of stimulating
business.

Visiting Day User Viewpoint. Most of the beach users during the
season come from many areas of South Carolina and from other states.
A majority of these day users come from Berkeley, Charleston and
Dorchester Counties. They are concerned primarily with problems of
low quality and crowded beaches; hazards to bathers caused by groins,
other protection works and root stubble; difficult access to the
beach; lack of parking; and lack of sanitary facilities for beach strands
distant from the central business district.

"Dynamite Hole" Viewpoint. The last identifiable group comes from
no specific locality and/or special interest group. These are the
people who are convinced, without factual evidence, that a dynamite hole
was blown in the south jetty at the entrance to Charleston Harbor by the
Corps of Engineers. They are vocal in expounding the liability of the
United States Government for eradicating erosion along Folly and Morris
Islands at no cost to the local people as restitution for damages caused
by the "dynamite hole". This group contends that closure of the "dynamite
hole" will immediately resolve the erosion problem. This group has been
referred to 19th century Annual Reports of the Chief of Engineers which
record the intentional design and construction of the low sections incor-
porated in both of the jetties protecting the entrance to Charleston
Harbor. The design appears to be working and it is the Corps' position
that the jetties are not affecting changes in the Folly Beach shoreline
to any discernible degree. The low weir sections "dynamite hole", are
discussed in more detail in Section C of Appendix 1.

From the preceding, it is apparent that the viewpoint as to what
* ~~~is a proper solution to the erosion problem is influenced mainly by
individual point of perspective. Boiling all of these viewpoints down,
it is concluded that the people want a cost and environmentally effective
solution that will receive significant Federal funding. They also feel
that the non-Federal cost should be supplied by the direct beneficiaries
of the work with little or no additional tax burden or direct cost
burden being placed on non-beneficiaries. As far as hurricane surge
protection is concerned, most would consider approval of this type of
protection only if the Federal Government picks up the tab, and if the
structure satisfying the purpose doesn't block views and/or interfere
with private land use and beach access.

Formulating a Plan

Formulating a plan that will satisfy the needs for beach erosion
control, hurricane protection, and solutions to related problems at
Folly Beach involves the consideration of several alternative measures.
Each potential solution was considered on the basis of its economic,
environmental, and social impacts. In order to formulate the best
alternative plan of improvement, it is imperative to consider all
appropriate alternative plans and assess all project effects - tangible
and intangible, favorable and unfavorable. Details of the plans con-
sidered and the formulation process are given in Section G of Appendix 1.

FORMULATION AND EVALUATION CRITERIA

Federal policy on multiobjective planning, derived from both
legislative and executive authorities, established and defines
the national objective for water resource planning, specifies
the range of impact that must be assessed and sets forth the con-
ditions and criteria which must be applied when evaluating plans.
Plans must be formulated with due regard to benefits and costs',
both tangible and intangible, and effects on the environmental and
17

social well-being of the region; and the plans must be institutionally
feasible.

The planning criteria uses a framework established in the Water
Resource Council's "Principles and Standards for Planning Water and
Related Land Resources", which requires the systematic preparation
and evaluation of alternative solutions to problems, under the
objectives of National Economic Development (.NED) and Environmental
Quality (EQ). The process also requires that the impacts of a
proposed action be measured and the results displayed or accounted
for in terms of contributions to four accounts: NED, EQ, Regional
Development (RD), and Social Well-Being (SWB). The formulation
process must be conducted without bias as to structural and non-
structural measures.

Formulation and evaluation of the plans of improvement for Folly
Beach including all possible alternatives, were based on technical,
economic, and intangible criteria summarized in the following paragraphs.
Such criteria permit the selection of that plan that best responds to the
problems and needs of the area.

Technical Criteria

Technical criteria used for the formulation and evaluation of alter-
native solutions to the problems of Folly Beach are consistent with
established Corps of Engineers Regulations. These regulations provided
guidance for carrying out the various tasks of multiobjective planning,
consistent with the Water Resource Council's Principles and Standards
and related policies.

Economic Criteria

The economic criteria which were applied in formulating a plan are
those specified by the Principles and Standards. Economic benefits were
developed in accordance with instructions contained in related Engineering
Regulations. Additional economic criteria used to develop the recommended
plan include the following:

a. A National Economic Development (NED) Plan was formulated to
maximize the net economic benefits while addressing project objectives.

b. Tangible benefits exceeded cost for the NED Plan.

c. All prices applied to estimated construction quantities are
based on April 1979 estimates.

d. A project life expectancy of 50 years and an interest rate of
6-7/8% were used in computing project costs and benefits.

e. Estimated construction time of the project is less than two
years, therefore, no iUterest was included during construction.

Environmental and Other Criteria

The following environmental criteria and intangibles were considered
in formulating a plan.

a. An Environmental Quality Environmentally Oriented (EQ) Plan was
formulated with the goal of making the most significant contribution to
preserving, maintaining, restoring and/or enhancing the cultural and
natural resources of the study area.

b. All alternatives considered were compatible insofar as was practical
with the surrounding environment.

c. All efforts were made to avoid detrimental environmental effects
and whenever feasible, mitigating features were considered for such effects.

d. Public health, safety and social well-being were considered when
formulating all alternatives.

e. Public acceptance of various alternatives was considered in
formulating each plan and feasible alternatives were coordinated with
interested agencies and individuals through correspondence, public meetings
and other procedures.

POSSIBLE SOLUTIONS

Several alternative measures to satisfy the problems and needs of
the area are possible; however, some of these measures are not practical
or economical. Possibilities include:

a. Nonstructural measures such as zoning and building code
regulations, flood proofing of both individual buildings or groups of
buildings and permanent or temporary evacuation of flood plain areas
and/or active erosion zones, and relocation of structures from these
zones.

b. Structural measures such as seawalls, revetments, offshore
breakwaters, and nourishment of the beach;

C. "Do-nothing" alternative which perceives the continuation of
existing conditions; and

d. A combinati on of structural and nonstructural measures.

Zoning and building code regulations are legal measures that could
be implemented and enforced by the regulating agency concerned to
effectively reduce the flood damage potential of an area in accordance
with a planned program of development and land use. Such action would
be desirable in order to preclude possible future development that would
suffer large damages. Table 2 summarizes the alternatives considered
in each stage of the planning process.

PLANS CONSIDERED FURTHER

Analysis of possible solutions indicated nonstructural measures,
other than those presently being implemented, to be of limited benefit
and point to structural measures as being the best means of meeting the
needs of the study area. The best non-structural plan was found to be
relocation of beach front buildings and allowing the shoreline to continue

TABLE 2

SUMMARY OF ALTERNATIVES

ALTERNATIVE STAGE 1 STAGE 2 STAGE 3

Relocation of Structures X X X

Evacuation Planning X

Flood Insurance / X
-J
Zoning & Mod. of Bldg. X X
Codes
)~~~~~~~~~~~~~~~~
, ~~~~~~~~1/
Regulation of Flood Plain - X
V)
Floodproof Structures X

Grass Existing Beach X

No Growth X

Do Nothing (No Action) X X X

Beach Development X X X

Beach Revetment X

Seawall X

Offshore Breakwater X X

Beach & Dune Development X X X
Dynamite Hole Closure X

1/ The City of Folly Beach is participating in the National Flood
Insurance Program and has implemented corresponding flood plain regulations.

Rev
6 Nov 79

eroding. In view of the planning objectives, and the technical economic
and socio-economiccriteria, beach development and beach and dune
development alternatives are the best all around solutions. Other struc-
tural measures: revetment, seawalls, and offshore breakwaters were
found to be more expensive and less enviromentally desirable. Accordingly,
along the "No Action" and "Relocation of Structures" plans, these two
structural plans were selected for consideration in greater detail.

Relocation of Structures. The best non-structural plan was found
to be relocation of beach front buildings and allowing the shoreline to
continue to erode. Based on the predicted long term future shoreline
shown on the aerial-mosaic (Plates 2 through 6) about 260 buildings
would need to be relocated. The present cost of relocating these structures
and purchasing new lots is estimated at $3,502,000 and the value of these
buildings that would be lost to erosion over the life of the project without
relocation is estimated at $6,425,000. Comparing the annual cost of relocat-
ing, $73,000, with the resulting average annual losses of buildings without
relocation, $79,000, the benefit to cost ratio for the relocation plan
is 1.08; thus, this alternative is economically feasible. It is not,
however, favored by those locals directly affected by erosion and
the danger of storm wave damage.

Do Nothing (No Action) Plan. The "No Action" alternative perceives
the continuation of existing conditions and no new solution for existing
problems. This option, although not favored by local study sponsors,
avoids both the monetary investment and potential adverse-impacts associated
with structural improvements. Effects of the "No Action" plan provides a
basis for evaluating impacts of the other plans.

Beach Development Alternative. The beach development alternative
was evaluated through the analysis of six different options which differ
only in scale. These optional plans are designated as plans A-0 through

Rev.
28 Mar 80
21

A-5. The location of beach protected by each plan is1-hown on Figure 11
and pertinent physical dimensions are summarized in Table 3. Figure 12
displays typical sections for the "Beach" and "Beach and Dune" plans,
respectively.

The Beach Development Plans would involve borrowing sand from off-
shore and restoring the beach to a fuller, wider section. Since natural
erosion would continue, the beach would require periodic nourishment by
pumping in more sand. A minimal beach berm elevation of four feet above
mean sea level and a minimal dry-beach width which will average 50 feet
between periodic nourishment operations was determined through stage
frequency and design analysis as that necessary to effectively resist
attack by normal wave action and the effects of frequent storms. The
usable dry-beach was considered to be the expanse between the hold line
and mean high water. Where a dune is incorporated in the protective
scheme, the usable dry-beach would be the expanse between the oceanward
toe of the dune and the beach face at mean high water.

Plan A-0 is considered to be the minimal plan since the length
of shoreline improved (17,000 feet) is currently experiencing critical
erosion, thus any shorter length would not be appropriate. The berm
width for the shoreline protected by this plan would average
50 feet between renourishment periods (5 years) but the flat berm at
elevation 4 feet, msl is expected to erode to zero feet width at the time
renourishment is due. Therefore, smaller plans than A-0 would not solve
even the most critical erosion problem at Folly Beach and thus were not
further considered.

Beach and Dune Development Alternative. Three beach and dune develop-
ment plans, designated as B-1 through B-3, Figure 12, were analyzed in
Stage 3. The three plansencompass the same reach of beach, Station 78+70S
to 180+90N, as shown on Figure 11. The main differencp in these plans is
in the degree of protection provided by the three different dune heights.
(Table 3).

Rev.
28 Mar 80
22

The main difference between the beach and dune development plans and
the beach development plans is the provision of an artificial dune system.
Derivation of the minimal widths of dune and beach berms necessary for
storm protection was based on an analysis of design storm parameters and
estimated corresponding erosion rates, Dune shore and seaward slopes of
1-vertical and 5-horizontal, and storm berm and beach nourishment fill
slopes of I-vertical to 30-horizontal were selected for stability.

After establishing horizontal dimensions on the basis of design
analysis, vertical requirements were evaluated. Determination of the

Rev.
22A 28 Mar 80

CAROLINA

~~~~~~~~~N. ~~~~~~~~~~~~~~~~~~~~~~~~STA 28(j

GEORGIA~4

OJECT~~~~~~~~~~'

B~~~~rdA IO
VIINT MAP

:ALTERNATIVE BEACH DEVELOPMENT AND
Point BEACH AND DUKE DEVELOPMENT LOCATIONS

I 0 I 2 3 ~~~~~~ 6 ~FOLLY REACH
SCALE IN THOUS FEET
SOUTH CAROLINA

FIGURE II

DRY BEACH WIDTH VARIES
PROPERTY HOLD LINE
(APPROX IMATE
LOCATION)
MIAXIMUM WIDTH
,.MINIMUN WIDTHjMS

GROUNID

BEACH DEVELOPMENT

DRY BEACH
WIDTH VARIES~
+12'MSL (PLAN-B-I)
Grossing ~+15'MSL (PLAN B-2)

0 NOTE: OF CON~~.i1'SIDRE (PLANS93

O'SL2.'MW T OLYBEACH. ANDDUN

REV. 28 MAR.'80 FIGURE 12

TABLE 3
SUMMARY OF BEACH DEVELOPMENT AND BEACH AND DUNE DEVELOPMENT PLANS

STA 24+70S to 27+OQN STA 27+00N to 143+90N STA 143+90N to 180+90N STA 24+70S to 78+70S STA 78+70S to 180+90N
Plan Avg. Berm Width (ft) Avg. Berm Width (ft) Avg. Berm Width (ft) Avg. Berm Width(ft) Dune Heights (ft msl)

A-O 50 50
A-1 100 50
1/
A-2 - 150 50
1/
A-3 150 100

A-4 100 50 50 50
1/
A-5 -- 150 100 50 50

B-1 1/
12
B-2 - 15

B-3 1 8

/ Plan will require lengthening existing groins seaward for beach widths greater
than 100 feet.

optimum dune elevation required a comparison of estimated costs for
varying-storm protection levels with benefits for each, level of-improve-
ment. Dune heights of 12 feet m.s.l., 15 feet m.s.l., and 18 feet m.s.1.
were analyzed. These would provide wave damage protection from storms
with frequencies of occurrences of 25, 50, and 100 years, respectively.

The estimated annual equivalent benefits, annual charges, benefits
to cost ratio, and excess benefits to cost are given in Table 4. It can
be seen here that Plan A-4 of the beach development plans and B-1 of the
beach and dune development plans have the greatest excess benefits to
cost of the two types of structural plans remaining in the iterative
process.

Flood Plain Management Alternatives. The best non-structural
plan was found to be relocation of beach front buildings and allowing
the shoreline to continue eroding, Based on the predicted long-term
future shoreline shown on aerial mosaic, Plates 2 through 6, about
260 buildings would need to be relocated. The value of these buildings
average about $25,000 each. Comparing the annual cost of relocation,
$73,000, with the resulting average annual building losses without reloca-
tion, $79,000, the benefit to cost ratio is 1.08 and the excess benefits
over annual cost is $6,000.

This plan and the do-nothing alternative would avoid potential
adverse impacts associated with structural improvement; both of these
non-structural plans, however, are not favored by local interest.

Selecting a Plan

BASIS FOR SELECTION

The selection of the best plan of improvement for Folly Beach in-
volved the comparison of the various alternatives which met the formulation
and evaluation criteria outlined earlier. Consideration was given to

23 Rev.
28 Mar 80

TABLE 4

COMPARISON OF COSTS AND BENEFITS1

Annual Avg. Annual Benefit Excess Benefits
Plan Benefit Cost to Cost Ratio to Cost

Beach Development Plans

A-O $ 887,200 $ 396,300 2.2 $ 490,900

A-1 953,700 419,800 2.3 533,900

A-2 977,500 460,400 2.1 517,100

A-3 966,300 523,100 1.8 443,200

A-4 1,060,600 521,000 2.0 539,600

A-5 1,060,600 620,500 1.7 440,100

Beach and Dune Development Plans

B-i $1,051,000 $ 996,200 1.06 $ 54,800

B-2 1,086,500 1,264,i0 0 0;9 0

B-3 1,105,200 1,589,400 0.7 0

1/ Figures are rounded to the nearest $100.

Rev.
'28 Mar 80

environmental effects, social well-being, the regional development and the'
national economic development. During the selection process, all alterna-
tives were presented to the public at a public meeting held at Folly Beach
on 29 November 1977. The transcripts of the three public meetings are on
file for public review in the Charleston District office.

System of Accounts. The System of Accounts (S of A) shown as Table 5
is a display requirement of the Water Resource Council, "Principles &
Standards" and is an iftegral part of the planning process. 'The System'of
Accounts displays all significant beneficial and adverse contributions
of each alternative carried through the final planning stage and provides
a useful tool to assist in the selection process. The S of A also satisfies
the display requirements of Section 122, Public Law 91-611, River and Harbor
and Flood Control Act of 1970. Table 5 displays the breadth and detail
of the assessment and evaluation of'allf alternative plans. Table 12
summarizes Table 5 and presents the crucial planning consideration under-
lying each alternative. Table 12 is presented later in this report in the
section entitled "Statement of Findings."

IDENTIFICATION OF "NED" AND "EQ" PLANS

The NED Plan. The Principles and Standards require the designation
of National Economic Developmentt (NED) Plan. This plan is described as
the plan which best addresses the planning objectives in a way which
maximizes net economic'benefits. Plan A-4, which addresses beach develop-
'ment only, maximizes net economitc benefits as is shown in Table 4. This
.plan, therefore, is selected as the NED Plan.

The EQ Plan. The Principles and Standards also require the designation
of'an Environmental Quality Plan (EQ Plan). This plan is described as the
plan which will make a positive contribution to the environment and
-the'most significant contribution to preserving, maintaining, restoring,
or enhancing cultural and natural resources. The existing conditions of
the study area weighed heavily in selecting an EQ Plan. Plan B-l,'which
addresses Beach and Dune Development, is selected as the EQ Plan. This

24 -

.........A - ...........TABLE 5 -SYSTEM OF ACCOUNTS
(For Explanation of Terms, .see Footnotes at end of Table.T-..

PLANA-0I (RECOMMENDE) -t ,.M -- r.0 ci - e
7' :
.,J PLAN A-o (OMMENDEO) I � PLP A 1-4 (RED) R ; MEDD RELOCATION OF STRUCTURES (EO 11958) 2/ NO ACTION
ACCOUNTS AND EFFECTS LOCATION OF oO
~~~~~~~~~~~~~~~~~MAT7 tLOCATIO N OF IMPACT ~; 4 LA -1�
ACCOUNTS AND EFFECTSLOCATINOFIMAC : ' LOCATION OF IMPACT 2~ : ~ LOCIIOI~IF IM*PACT LO:_ CATIONKor IM~PACT F rLOCATION OF IMPACT O
~~~~~~~~~~~WITHIN tITHIE-
1. Natioal Econmic WITHN T~lE ITHIN THE REll *S IhI TE WHIN THE REST cc TE THE HOS ! ao j WTHITlE REST . 0 WIHNTE[ITHIN THE REST fj
ITH~~~~ ~ WITHIN TH[~jHN~E RS
1. National Cconomic . , W
UIT'rr ;" S~voYAR~lloFHWNATOO r IN TAE TWITHE FWXTHI THE T4TI RRE
Development STUDY AREA OF THE ATI STUDY AREA OF THE NATION STUDY AREA F THE NATION ITHIN THE STU OF THE ATION STUDY AREA OF THE NATION

a. BeneficIal Impacts
(1) eatch Erosion -
Annual 6 209.500 1 6 9 9 304,000 1 6 9 $i304,000 1 6 N
(2) Recreation-Annual 681,500 1 6 9 76D.600 1 6 R 738.100 1 6 9

(3) Hurricane Wave
Ocarnage 0 1 6 9 0 1 6 9 12,900 1 6 9 79,100-
(4) Total NED Benefit
-Annual 0 891,000 1 6 9 01,064,600 1 6 9 91,051,DOD 1 6- 9
b. Adverse Impacts 1

(1) Project First
costs t92,554,000 1 6 9 3.D01,R000 1 6 9 $9.826.000 1 6 9
Costs 8.0
()Amtnual-0Cpi tol
Custo l8l.700 -1 6 9 256,400 700,300
(3) Annual OHM Costs 2253600 1 H 9 277.600 1 6 9 309.100 1 6 9

(4) Total Annual Cost * 4074j00 1 6 9 0 534,200 $;009.400 9 73,IDO4y

c. Mat NED Benefits $ 483,700 1 6 9 $ 530,400 1 6 9 9 45,600 1 6 9 0 5,800
2. Environental Quality WITHIN THE STUDY AREM W ITHIN THE STUDY AREA WITHIN THE STUDY ARE WITHIN THE STUDY AREA WITHIN THESTUD Y AREA

a. Environmental Qpuality
Enhanced
*0l) Esthetics , Three miles of critically Three miles of crititally SaBe as Plan A-A.. Approx- Ho sobanc.nent of beach. No No enhancement of beach.
eroded beach would be i- eroded beach pins two addi- inately 4 mA. of additional ench.ncemsnt of dunes. Ho enhancement of dones.
stored which would nhan tlonal miles of eroded veetated des would enhane Dlie in visitatin rate Decline In visitation rate
sApln qualities. 1 6 9 beach ould be restored, natural beauty & provide may reduce litter & traffic may reduce itter traffic
ScenIc enhancement would be visual isolation of beach congestion problems. 2 5 9 cngestion problems. 2 5 9
greater than A-0. 1 6 9 from traffi & co6 9roil
activity. Unsightly seasalla
revetments would be con-
(2) Man-made N. addicisoul eohancement. No additional eshaneent. ered by dune syates. 1 6 9
Resourtces Throat of wave & hurricane 'Threat of-wsve & hurricane Threat of - 6 hurrica.. N. Positive contribution. No positive contribution.
damaue would be reduced huL donege would he reduced mere
to * -oaleor deg... than than for A-O but less the. damoge would be reduced
fo A-n orual $ 1 6 9 f$1 1 6 9 Bomre than for A-, or A-i.
(orA-4or -1 1 1. -I )9Prstectlon from 21-year
Ioprov'd atorm prutectian I orovod cocm prttion would at would result. 1 6 9
would encourage maintenance -n-ourage mainctnauoo & Improve- Ho positive ontribution-
& inyrovement of homes 6 went of homes & osusercial es-I Inproved scorn prutecriom
coconertlal eot�biahlohnws, tablishments to a greater extet woold encourage ainran-
but to . matter degree than A-D but a smaller degree ac & inprovomonta of
() Natural hrhomes & coercial eatab-
(3) N tlthan A-4 or n-1. 2 3 9 than s-1. 2 5 hmes t a
Resources* lishmot. to . greater
Three mile. of c-itie-ly Three miles of critically extent than A-O or A-A. 2 5 9 Ho enhancement of beach. N . enhancement of beach.
eroded h.ach w.uld be eroded heach pluF two addi- Ho Inhancomomt of domes. No enhancement of dunes.
restored. 1 6 9 riunal miles of aroded beach enaplnA.Apr.
would Ie restored. 5 6 9 4 mules of add'i vegetated
Ho additi..al I2ancem60t. o additioal enbancomdnt. dune0 would provide habitat
'(4) Air quality* for roddntn .r0bbht,blrds.I
No -h-ancement. Some benefit to island vege- Decline in visitatiom rats may Decline in visiratfon rate
*(5) Noiset * H No oba mennt. Ho enhancement. tacion would reult tin add'l reduce auto omissions. 2 1 9 may redu sure snuoi . 2 1 9
c- Ne ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~at spra prncfction 6 8,0

~b. Envi~ronmental Q(ualIty (4)No y enhancmnt.I 6 9 D$cline i visitation rate my Decline is visitatuon rote
Ug. nradeda ult (4) No a tet rednce traffic & people noise. 2 1 9 may reduce traffc ic e. 2 9
Degraded (5) N.J.. from auto tf
'(T) Estheticst Litte & trashon Ieandcape .ittsr trash an landscape &. oorrcial enactivities.. Ho enhancement of beach.
may increas e in proportion my I a in proportion c 7ud l al d enhanemet of dunes. No nogative omtrf ustan.
tor highouerc tinse l ,Iogtatiedunraeo higher visitation rate. Effect system. 6 ilings and foundations left from
senic.r qualitie. 1.�I 6 behn ouldL~l~ ~ bfect r e stoed.

�fin.ct old ho . .n. . would be more severe than A- relocated structurea my be No negaciva otntribucio.
ocusre than A-A or 5-1. 5 9 but less than B-1. 12 5 9 itt., & trash on aunnightly. 2 6 9 U.nhecied erosion would peretn
Traffic constiom may io Traffic congestion ay io Incae t ph oat constructIon by prop-
, Scenic enhanetold e con-st fion ..problem
cre1so in proportion to in proportion to higher visi- tfocto would he mere severe erty oners of snsightly
higher visitation rate, ration rats. Effects would be oeavslls. renetmeets etc. 2 6 9
Offsets would be I... aavsra mere severs than A-U. but less 2 1 9
than A-4 or Sh. 2 9 severe than 9-1. Traffic co ngestion may in-
crease in proportion to
~~~~~~~~~~~~No negaSctivit . contribution. high
W. negative oot'ib~~~~~~~~~~~~ti.".he vi Itatee.rte
Effecte would be more
severe than A-O. 2 5 9
*(2) Man-made No negative cuntrihution.
Mdtb Nou l negative cottrihutiom. Ho negative contriburtion. Threat of wave and hurricane Nh.t of wave hosicnt
Resaurteun Ho negative cuntribution. 'b~~~~~~~Treat of wave & hurricane

IARsuce No negs W: -trluti... damage would continually worsen 1 9 damage will corntinually
worsen. 1 o 9
-(3) Natural R esources tn-thic anunite of enrthic om- unitiles of thic an of
borrow and hench fill borrow sod boach fill borrow & beach fill areas No negati-e contribution.
oreas woul d uffer temn- area would uffr mp- would uf or teporary
rary population reductin. orary population reductions, population reduction.
sw~ Recovery oould occur in ecovery ahosld occur int Recovery should occar in
6 to 18 ohs. Adverse 6 to 18 mnth. Adverse 6 to 18 m-nth. Adverse
efect would be less -evre efiect would be mhare -ever ff-c wo..ld be .more .over
than
Resv.

TABLE 5 - SYSTEM OF ACCOUNTS 4CONT'D)
(For topl-nario of Terms, see Footnotes t nod of Table.)

FL~~~il A-I (REC~~~~~~~~~inI~~~~nDED) - FlA~~~~~~~~l ALOCATION Oo' STRICTCRES N)0
PLAN A-1 (RECOMIENDED- PLA Al-fp4 ( M LNB1EQ-- (En -1 .
~~C C- AND _g-CTS LOCATION OF IMPACT --. ---ED)FNI )ED) 11900) 0" ACTION
COO AND EFFECTS LOCATION ~~~~~~~~~~LOCATION OF IMPACT OCTO FIPC n - LOCATION OF IMpACT N OO A LCATION O MATo
AtONE o. A a a ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~LOCATION FIMPC n. 00 0 LOCTO OFIPC

0(3) Na 'ra Nenre 'hen A-A or N-I done to snalln than A-6 bar loss --even. I
~~~~~~rqld-I. ofll.ntd 6 9 than S-1. 1 6 9 A-O so A-4. I1 6 9 Enioring dunes and dune Rotasting dunes and done
N. N.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ vegeta-Otion nay. suif- vegetation slysffer
Na negative nourrihurion. No negation nontnlhution. Eninting dne vegetation donoge Or destrd rrion if dafage or dostructinaif
nay ha danged or deotroy-ersoatrdsc-eoinltedsntnu
ed., in anneamst-ti ti-u unuheched. 2 9 -9onheched. 2 1 9

...trib~~~ti... r~~ntrib~~ti... V~~~gVgetationwouldbh re- Anoot of dry bench Annut ni dry bea..n area
No nogotbvo ountributios. No negation nonlrihution. pluonPI rd an Part of the area wola nontiue to ol ntnu odnno
proposed antion. 1 6 9 dim~isih if nonsinon if erosonal trendu on
No negationenriuln toondo ountinsen- tin..u.. unhonkd. 1 6
ch-enhd.16 9

0(4) later Quality0 upoo tuohidity Eron Effects ainilar to A-S Effetat siilar ta A-O N. negatine nontrih~totln Nsugarion nntrihuttn..
projeot..nootrction -Iud bnt onrenoere. Effents but 0r. severe than
oar in aeon of dredging loon --0 than f-i. 1 6 9 A-O or A-4. I1
& near, bnanhd1fIl'sites.
ifoto would be I...ss evere
than A-h no N-i sIn.e ... aller
~~~~~~~lasr - itienS of netnooi.. ooId
he~~~~~~~~ 6

cresse in proportion to tot a-).. 195 9 entont tha1n Tur A-S or -
highervstto rate. A-4. 2 1 9
-(6) N~~~i... lfecto ...Id be loss $00000
961 1101000 ~~~than A-A or N-I. 2 5 9 Effnnis ...Id be sinila ifiotn would ho ninila N. ne~gativl otiuin- No-eaionotloin
N-ise f- tt~ffic end h- to A-O. N-is. ...Id bo C . t A-S. Nolan ...Id be
No'ise entofI ad huna reater pruhlen than ion ouren..-re than for
hciiywudinthcun ~int A-0 hut I... then for S-i. 2 5 9 A-S or A-A. 2 5 9I -

tino rote. ThPis ..a ...uld
load.t lwrhpooh onls
levels than A-A or 0-1. 2 1 9

WITHIN THE WIThIN THE REST WIThIN THE iITHlIN THE NRlWTI OE W~I O EST IONTE WTI O INIIHNTEOI NTE04
STUDY AREA OF TOE NATION STUDY AREA JOF Till NATION SITHIARA I THE WATION ITD ARES FTO WITHINOIN STUDYT AREAO THE SATI`CI '

'0I) ioe-uitp Cahesin' Inocas ..hubt logligihiblranno nigbeIcoaeor olgboN oiio NelgbeN oiie Ngiil

4)2) Cosenonity Growth Sl~~~~~~~ght inoceose-r Negiil nooc eonNgligolbe Ioreasn our. Nogligible N. pooltiv N.giil No uiie Ngill
Iols th-an4A- tho A- Iut than A- ortA-h 2 1'h
A- r51. 2 1 9 lo thou _J A-a. 2 5 9ff2

-(2) nCreatia Incrase Sligt i. .. Negligible luroso noce lo)9h0Ive sno lgigibeI N- pooltive Nogligiblo opstveNgiil
Opportuninins Ions than 5Lhan A 1-i but C)u A- o4 2 ilfc.to. 2 6 ' 9 ' I Neffogib.
or4 f-I. 1 6 9 loss than 0-i. 1 6 9 A-A. 1 6 9

0)1) Coomnucity. In- N adverne. h Nefligihie soovrn Ngiil odes elgbyOcrae nliheDcess Ng1il
opp-t-it loadvees NoiAgl No s adec e Negligible INa .....rse Negliglbe N . u reasno Negligible 2 1.- Onctoasn Nogligible
0)2) Coseounlty Growth effectn 2 1~~~1 9 leffeto.. 2-1 5 9 Aiivt.25 9

(3 hRnraioa Noavos Nogigbl No.. advetto NelgbeN dcu liglblo erae NoglIgIble I D9Icreases Negligibln 2 6 9
Opportunities efets. 1 6 9 2leno 1 9 efecs I 9A 9

Fepl an No advrs flgiil nuvco olfboN dvoo Dn-gi--lnoo Negligibly 1 6 9 lNoeos egligihln 1 6 90
Poeroiyh- efcs 1 6 9 efico 1 6 9 efet.1 6

a.4 Onoiil nat
0. 0() on ones IdN.ran d-am Nogligible HInomeane t NegligiblN- rvd-o grea- Negigbl Nopsito lgbeN u~ieNgiil

C- lty Ot. tbasA-Aoo-i 1 6 9 vbsiI 1 6 9 fA-A. 1 6 9 Ngii l 6 9 - -Ngiil

0(2) Values Increases pm0- Negligihln Inur~eases pop-Neligthlo loorease propt- Nogligihln so poslive- Negligible No posttive Nogligihie

chas I-h or 3-1. 2 A1 9 thI. 2-. 6 9 bA.4 .- A

TABLE 5 - SYSTEM OF ACCOUNTS (CONT'D)
- - - - ~~~~~~~~~~~~"'on Explanation of Terc see end of Table.)

PLAN A-I (NECOOIIENIEI) - - p~~~~~~~ A4 o~~~m 0 ~~ ~ ,~~ 5~ RELOCATION OF STRUCTURES 40
- - 5 - -a a -~~~~~~~~~~~~~~~~ .4 (~~~~~En 119Sf) - F N CIN5.4a ea '4 _4 ne
AGCWONT ANDI EFFECTI LCTOOPIAT 4. S LOCATION Of IMPACT .5~ 2 CLOCATION OF IMPACT .40. OAINO IOI 0 a~ LOCATION OF IMPACT .
WITHIN THIE WITHIN THE REST 0. 4 WTI N WITHIN THE R~t5 4 4 WIT1lIN THE W'THIN THE RE! T e _qINNm INI HRA
ITUDVANREA OF TM NATION 4- a S ITUDY A.EA OFpTHENATIOO WITHI THE I4 W ITHIN THERES WI HINI TH wlTHlINTHE HEj A a
4.Otbeo~~~~~~nos~~~~nianffsns. 540.444 ~ ~ ~ ~ ~ ~ ~ ~ ~~~ *~TUDY AREA OF THENATION T- .

a. Nenefisisi Impants

(3) Poblin leonine N. petition Negligible 2 A 9 bs pesitive Negligible 2 6 9 N. penitive Negligible 2 6 9 Na position Negligible 2 6 9 N' petition Negliglble 2 6 9
efet.efns fo~.effects. efens
(4) Regi . ..na grwI eagina reiea effects. effects,

I unneses no- NeglIgible 2 5 9 Innocence. NeglIgIble 2" -
Fence~ ~~~~~~~~~~~~~~~~ 5hfe~!~ 9rEn ..... cane Negligible 2 1 9 Napoitv Negligible 2 5 9 No positinNggbl 2 5 N

A-14 or Bb-t.YA-0 oneia
(AFosines sod Innoanesbaa Negligible 2 1 9 I'r. ANOg00 A-l. 2 1 9
led Antinity psco,&ldJnnan eliil , 9n Inceen Negligible 2 5 9 N. puaitive Negligible 2 1 9 N. positive Negligible 2
ctivit A-t oxins br. baiessb..ct..fo

(6) --iea&and. .... A-S- Nelgbut 2es noon- -1 thee
b.Av nsEfenibnI. A-i no A-4.
0(1) ~ ~ ~ ~ ~~I.~ Tan inene Hilionae Rqie a 9 Wl cnes eliil 9 Hl n Negligible 2 A 9 oN.oesnen Negligible 2 A 9 leNeasest Negligible

Bnnaion enpntl no.cl A-i
b ~~~~~~~~~~~~~~~~~~rAter. ..hant..

- Ad-r.. ~~ Effents. effects. Anifents-.
0(3) T..l~ Paen..illtie... Nghen. cattegiil 1 6 9 Wilnnele in.. NeglIgible I 6 9 loonescli... Negligible I A 9 DOnnoasess Negligible 1 6 9 D ecreases Negligible 16A 9
to metnit-. renan btot. o dean too
neetIn ... Itlest aofve. above A-I0
Copeation dnad -At-I leon oban A-4.
I-.
'(4) P-blin Vleonin N. dhe...s E Negligible 2 6 9 N.ge public Negligible 2 6 9 HihN poblc Negligible 2 A 9 lenn.a..s Negligible 2 6 9 Deenase. Negligible 2 A 9

effect..efnn nifecto.
0(6) Enplaynsent/Lsben No negative Negligible 2e 9 9- ... neaIv Ngiibl onegtv Negligible 2 6 9 leor..se. Negligible 2 1 6 9 lenoe.s.s Negligible2 1 9
0(2 Noinss nd ed go egt.v --i 2 1 Na negatio - 1 9 Ncdegaiv d 2 oe on
Activity effecltia, afets, effects.f
44(g) ~ ~ ~ -a Oiplnoes ofi Non - Neo - ue-Nne-Nn
Fg~~~~tronsdm..A~ b4

inlatati e oftb la.inat Es5%onnnin .stcon.1.Ipn il nu sywe pcfc pli lentv eetd
2.lese s npnedvlbl ) eanfoloig . heucetany s eten 0 07. t Oeeapig nty nt olyadltoelanieo sn anid c a docsdhy lodPll

f ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~ ~4 EsNnte anua nnttoonect
-( 6 E APl EyItcL rN denutesiteo Npegligicbllv 2 Netoon in itioo N12iib2 219 Nnt- N gi b l 2 9DersesNdgigbeogened Neglngioes ad cotet
oFPor..La 161 c effe'sailee. to acf eneio to cb

is based upon its prevention of loss of existing man-made and natural
resources in the zone of expected erosion while effecting the restoration
and vegetation of a dune line. This artificially restores a natural
feature which provides limited wildlife habitat and screens the commercial
and residential development from the view of recreationists who use the
beach.

SELECTING PROCESS

Plan selection is the designation of the most desirable alternative
based on results of detailed study. This selection is also influenced
by the public response to the various plans considered and institutional
constraints affecting plan implementation.

The structural plans considered for implementation, "Beach Develop-
ment" and "Beach and Dune Development" plans have a high degree of ac-
ceptability with local interests. Plan A-4 has the most excess benefits
to cost of the "Beach Development" plans, however, Plan A-0 is considered
the more viable because of the lower non-Federal investment required. Plan
B-l has the best benefits to cost ratio of all the "Beach and Dune Develop-
ment" plans but it is economically marginal. All of these plans require
a substantial increase in first cost and non-Federal participation when
compared to the "Beach Development" plans. The No-Action plan and the
Relocation of Structures plan are deplored by those directly affected
by erosion.

For structural plans considered in the final planning stages,
cost sharing between Federal and non-Federal interest, based on shore
ownership and use, is shown in Table 6. The non-Federal amounts
shown include five percent of the total initial project costs to be paid
by the State of South Carolina. This front-end loading is part of
President Carter's new cost sharing policy. Cost apportionment for
the selected plan of improvement is discussed in later paragraphs.

TABLE 6

COST APPORTIONMENT (IN $1,000)

Initial Cost 5-Year Renourishment & Dune Maint.
Plans Total Federal Non-Federal Total Federal Non-Federal

A-O 2,393 722 1,671 1,292 496 796
A-1 2,723 853 1,870 1,292 506 786
A-2 3,292 1,057 2,235 1,292 510 782
A-3 4,171 1,356 2,815 1,292 509 783
A-4 3,410 969 2,441 1,596 573 1,023
A-5 4,805 1,400 3,405 1,596 573 1,023
B-1 9,634 5,028 4,606 1,778 568 1,210
B-2 13,283 7,136 6,147 1,823 568 1,255
B-3 17,729 9,644 8,085 1,871 568 1,303

Rev.
28 Mar 80

THE SELECTED PLAN

In view of the overall evaluation, design criteria and planning
objectives, the plan previously designated "minimal plan", Plan A.-0,
is selected for implementation. This plan in combination with non-
structural endeavors that have been established in the study area will
provide for meeting the existing and future needs for erosion control
and recreation. Details of the minimal plan are presented in Section
H of Appendix 1, which is entitled "The Selected Plan".

The Selected Plan

The preceding section summarized plan formulation and identified
the plans with the best potential for resolving the problems and needs
of the study area. The following pages present a description of the
selected plan, including its accomplishments and effects as well as
its significant design, construction, operation and maintenance aspects.

DESCRIPTION

The selected plan provides for beach restoration and periodic
nourishment for that 16,860-foot developed reach of Folly Beach in
which manmade improvements are in greatest jeopardy. This reach would
have a berm width of 25 feet. The berm would be constructed to an ele-
vation of four feet above mean sea level and would be fronted by a
beach having its face slope at about 30-horizontal to I-vertical. The
beach fill section would provide an average usable width above the mean
high water line of 50 feet. The slope of the beach face would be formed
by natural forces during and subsequent to material placement. Machines
may be necessary to slope the berm depending upon the skill of the
contractor in placing material. Plate 7 shows the location and design
sections of the selected plan.

In those areas where fill is to be placed landward of the "hold
line", such placement would be made to effect proper drainage. Where
possible, runoff would be directed landward to avoid the erosion of sheet
flow on the berm and beach face.

Initial construction would consist of dredging approximately 684,000
cubic yards of material to place 536,000 cubic yards on the beach. The
amount of beach fill required for initial construction is based on
profiles surveyed in April 1977. Material placed would satisfy three
purposes: beach restoration, private fill, and sacrificial nourishment.
These are depicted on Plate 7 at the end of this report. As the material
is being placed, it is subjected to the natural sorting of waves, tides,
and currents. Approximately one-half of the material would come from the
southwestern direction using Stono Inlet ocean bars as the source. The
other half would come from Lighthouse Inlet ocean bars, northeast of
Folly Island. Laboratory tests of this borrow material indicate that
1.4 times that quantity needed on the beach would have to be taken from
these borrow areas.

Periodic rernourishment would be required at approximately five-
year intervals. Each of these efforts would require the borrowing of
approximately 354,000 cubic yards from the same self-restoring sources.
Materials dredged from shoals occurring in the Folly River small navi-
gation project would be utilized when practical for initial construction
and renourishment efforts. Material taken from Charleston Harbor entrance
channel via hopper dredge may also be utilized if pumpout capability is
developed sufficiently to make this operation economical.

PLAN ACCOMPLISHMENT

The addition of sand to the present beach, would provide a wider
beachfront that can accommodate a larger number of visitors. This would
act as an added attraction to the area, encouraging an increase in local
and tourist visitation,, It is estimated that the available beach area
in 1980 without the-~proposed plan would be only about seven acres. With
0 ~~~the proposed plan, the available beach area (from landward end of the
artificial berm to mean high waterline) would be approximately 19 acres.
Estimated selected plans are discussed in Section E of Appendix 1.

Rev.
27 28 Mar 80

Direct beneficiaries of the improvement would be the property
owners and commercial interests along the shorefront who would receive
protection from erosion; resident beach users and tourists, originating
mainly from the State of South Carolina. Overall beneficiaries are
numerous and widespread, being essentially the general public, although
they are concentrated generally in the greater Charleston metropolitan
area.

ENVIRONMENTAL EFFECTS

Implementation of the recommended plan would produce several
beneficial effects, including improved appearance of the beach, in-
creased recreational dry beach area, and improved protection of shore
structures against erosion.

Accompanying adverse impacts would be temporary and minor. Water
quality would be slightly degraded in the vicinity of the dredge cutter-
head and adjacent to the nourishment site as localized increases in
turbidity and possible reductions in dissolved oxygen occur. No sig-
nificant biotic impacts should be generated by these conditions and
water quality shoud return to normal within several days after project
completion.

Mortality of benthic organisms and associated population re-
ductions would also occur in borrow areas and beach nourishment sites,
but colonizers of the same or similar species from nearby areas should
reestablish viable populations in the affected areas within a period
of several months.

Physical and biological effects of project maintenance would be
similar to those of project construction but of a smaller magnitude.
Project implementation would not significantly affect any rare or en-
dangered species nor would it cause significant irreversible commitment
of natural resources.

CONSTRUCTION

0 ~~~~Estimated time of initial construction and renourishment is less
than one year per effort. During each construction effort, techniques
would be employed that result in minimum losses to winnowing and in
minimum machine work to shape the artificial berm. Performance of the
artificial fill would be evaluated at a regular interval to determine
the appropriate timing for renourishment efforts.

In order to provide for abatement and control of any environmental
pollution arising from construction activities, the contractor and his
subconctractors would be required to comply with all applicable Federal,
State and local laws and regulations concerning environmental pollution
control and abatement.

OPERATION AND MAINTENANCE

Management of the recreational use of the beach including life-
guards, trash removal and police and rescue services would be the
responsibility of non-Federal public agencies.

Economics of Selected Plan

METHODOLOGY

The tangible economic justification of the proposed improvements
ca n be-determined by comparing the equivalent average annual charges
(i.e., interest, amortization, and maintenance costs), with an estimate
of the equivalent average annual benefits which would be realized over
the 50-year period of analysis selected. Appropriate values given to
costs and benefits at their time of accrual are made comparable by
conversion to an equivalent time basis using an appropriate interest
rate. .A rate of 6-7/8 percent applicable to public projects was used

in this report. Interest during construction was not costed as the
estimated construction period doesn't exceed two years. Recreational
benefits are based on estimates of population and growth, beach use
supply and demand, added opportunities created by the Selected Plan,
and unit values of these opportunities.

ESTIMATED FIRST COSTS

Estimated first costs are based on the quantities previously
discussed herein. For alternative comparison and for display of the
Selected Plan, materials placed on the beach were assumed to have been
taken in equal amounts from Stono Inlet and from Lighthouse Inlet. The
estimated unit cost of dredging, transporting and placing this material
is $2.40 per cubic yard. Mobilization and demobilization costs, using
this borrow scheme, is estimated at $120,000. Should all of the material
be taken from only one of these borrow areas, the unit cost and the
mobilization and demobilization cost would both be greater due to the
longer pumping distance. If all the required borrow sand would be taken
from Lighthouse Inlet the unit cost would be $3.00, and mobilization
and demobilization cost would be $150,000. Using only Stono Inlet,
these costs would be $3.20 and $160,000 respectively.

The initial cost of the monitoring program is estimated to be
$7,000. This includes surveys, sand sample collection and analysis,
and preparation of a report.

Estimated first costs of the Selected Plan are separated into
"Federally Shared Costs", which would be cost shared between Federal
and non-Federal interest, and "Non-Federal Cost" which would not be shared
since this fill material would ,be placed on private property and will
be totalfly a local cost. These separable costs were used in Cost
Apportionment shown in Table 12. First Cost Estimates are shown in
Table 7.

TABLE 7

ESTIMATED FIRST COST OF SELECTED PLAN

Item Cost

FEDERALLY SHARED FIRST COST/
(Federal & non-Federal Costs)
Mobilization and Demobilization $ 120,000
Beach Fill (634,000 cubic yards @ $2.40 per cu yd. 1,522,000
Contingencies @ 20% 328,000
Total Federally Shared Construction Cost $1,970,000
Engineering and Design @ 5% of Construction Cost 98,000
Supervision and Administration @ 6% of Const. Cost 118,000
Beach Monitoring Program Cost 7,000
TOTAL FEDERALLY SHARED FIRST COST $2,193,000

NON-FEDERAL FIRST COST
(No Cost Sharing)
Beach Fill (50,000 cu.yds. @ $2.40 per cu. yd. $ 120,000
Contingencies @ 20% 24,000
Total non-Federal Construction Cost 144,000
Engineering and Design @ 5% of Construction Cost 7,000
Supervision and Administration @ 6% of Const. Cost 9,000
Lands 40,000
TOTAL NO1-FEDERAL FIRST COST $ 200,000
TOTAL PROJECT FIRST COST $2,393,000

'1/ These costs will be shared by Federal and non-Federal interests
according to the percentage of shoreline ownership and use by
public and private interests.

Rev.
28 Mar 80

PERIODIC RENOURISHMENT COSTS

Estimated costs of each renourishment effort made on an average
of once every five years during the 50-year project life are shown in
Table 8. Costs shown include the Federal share and the non-Federal share
of total renourishment costs. Cost sharing between these two entities
is shown in Table 11 after the discussions on "Cost Apportionment".

TABLE 8

ESTIMATED RENOURISHMENT COSTS,
FEDERAL AND NON-FEDERAL (5-Year Periods)

ITEM COST

Mobilization and Demobilization $ 120,000
Beach Fill, 354,000 cy @ $2.40 850,000
Contingencies (20%) 194,000

Total Construction Cost $1,164,000
Engineering and Design (5%) 58,000
Supervision and Administration (6%) 70,000

TOTAL 5-YR NOURISHMENT COST $1,292,000

ANNUAL COST

An amortization period of 50 years was used with an interest rate
of 6-7/8 percent for both the Federal and non-Federal contributions.
No interest during construction'has been included since construction
should take less than two years. Estimated average annual charges are
given in Table 9.

Average annual cost of the monitoring program is based on surveys
and sand sampling being done prior to placement of initial fill, once
per year for the first five years, once during year 7 and 10 and every
five years thereafter until the end of the 50-year project life.
31

TABLE 9
ESTIMATED AVERAGE ANNUAL CHARGES

ITEM COST

FEDERALLY SHARED

Interests and Amortization on First Cost
{$2,193,000 1/ x 0.071317) $ 156,400
Beach Renourishment
($1,292,000 2/ x 0.071317 x 2.4083841/) 221,900
Beach Monitoring Program
($7,000 x 0.0713117 x 7.469034 4/) 3,700

TOTAL FEDERALLY SHARED $ 382,000

NON-FEDERAL (NO COST SHARING)

Interest and Amortization on First Cost
($200,000 -Jx 0.071317) $ 14,300

TOTAL AVERAGE ANNUAL COST $ 396,300

1/ From Table 7, minus monitoring cost.
2/ From Table 8
3/ Present worth of nine maintenance operations at 5-year intervals:
(Present Worth 6-7/8% - 45 yr. EPS) = (13.815484 = 2.408384
(Compound Amount 6-7/8% - 5 yr. EPS) 5.736412)

4/ Present Worth of 16 monitoring operations = 7.469034
Post construction monitoring involving 15 operations is computed as:

7,000 x 0.071317 x 6.46903 = $3,200
5/ From Table 7

BENEFITS

Estimates for monetary benefits are based on April 1979 price
levels. These are classed as (1) prevention of losses to real property,
(2) enhancement of private lands, and (3) preservation and supply of
recreational opportunities. Losses to real property break out into two
sub-classes, land losses prevented and building damage prevented including
contents. Details on the methodology employed in quantifying benefits
are given in Section E of Appendix 1. A summary of the benefits quanti-
fied monetarily is given in Table 10. Rev.
32 28 Mar 80

TABLE 10

MONETARY BENEFITS

Class Annual Benefit

Protection of Real Property:
Land $ 119,200
Buildings 51 700
Enhancement of Private Lana 34,800
Recreation 681,500

TOTAL $ 887,200

Rev.
28 Mar 80

BENEFIT-COST RATIO

.In order for a proposed project to be justified from an economic
viewpoint, the average annual benefits for the plan should equal or
exceed the average annual project cost. All monetary values are based
on a common dollar value and are expressed in comparable terms to the
fullest extent possible. A benefit-cost-ratio of 2.2 was computed as
follows:

Benefit =$ 887,200 =2.2
Cost $ 396,300

Division of Plan Responsibility

As previously noted, the responsibility for various non-structural
measures, such as zoning and building codes, and for flood proofing
individual structures is non-Federal, although technical advice can be
furnished. This does not preclude the possibility that assistance may
be available from other Federal programs. The division of responsibilities
for the selected beach development plan are discussed in the following
pages.

Legislative and administrative policies have established the basis
for Federal and non-Federal sharing of responsibilities in the construc-
tion, operation, and maintenance of Federal water resources projects.
Significant in this regard are the sharing of first costs for construction
and the responsibilities as well as the costs for renourishment. These
are discussed in the~following paragraphs. Other general non-Federal
responsibilities, such as indemnifying the United States, and continuing
public use of the pr'oject shores are not discussed but are set forth
in the "Recommendations".

Rev.
28 Mar 80
33

* ~~~~~There is an unsatisfied need for public facilities in the study
area. Shortages exist in the supply of adequate parking spaces,
bath houses and comfort stations, and/or public transportation for
beach users. Beach access is currently provided at street ends
and is considered to be adequate. Non-Federal interest would be
required to insure that a sufficient number of these access points
remain open. There is presently about 325 off-street parking spaces,
750 private driveways, and 3,752 spaces on the city streets which
could be used by visi tors to the proposed beach-fill project. An
analysis of parking spaces needed, in order for project beach capaci-
ties to be utilized revealed that 92 additional parking spaces would
need to be constructed on the north eastern segment of the project
area or public transportation provided to make up this shortage. Local
interests have plans for a shuttle bus system. (See pages H-6 through
H-9 of Section H, Appendix I for details of Associated Public Facilities).
They are also in the process of adding bathhouses and comfort stations
to the central portion of the project area. This portion of Folly
Beach would have adequate sanitary facilities with the existing and
proposed new works. However, five additional comfort stations with
outside showers will be required to service the remainder of the
project area. These would be spaced at about one-half mile-intervals
in order to limit the walking distance to these facilities. Costs
of providing these needs have not been included in project cost esti-
mates as these items are considerd self-liquidating. In view of
the recognized unsatisfied need, non-Federal interest would be required
to provide facilities to satisfy unmet needs associated with the
proposed public beach development project.

COST APPORTIONMENT

The policy of Federal aid in the restoration and protection of
shores against erosion is set forth in Public Law 87-874, River and
Harbor Act of October 1962, which amended Public Law 286, 84th Congress.

Under the provisions of Public Law 87-874, Federal participation in
the construction cost of beach erosion control, exclusive of land and
damage items, is limited to specified percentages dependent upon the
ownership and use of the shores. For public shores, sharing ranges from
50 percent to 70 percent. For private owned but publically used beach
which currently is the case at Folly Beach, sharing of project cost
by the Federal Government is limited to 50 percent multiplied by the
ratio of public benefits to total benefits. Recreational beach use
benefits are the only public benefits accrued to the recommended project.
Of the $887,200 of annual benefits projected for the project, $205,700
are derived from the protection and enhancement of real property and
$681,500 from recreational use of the beach. The Federal contribution
of project cost to be shared between Federal and non-Federal interest
is computed to be 38.4 percent and non-Federal is 61.6 percent. Costs
to be shared include public beach restoration, periodic nourishment,
and a beach monitoring program.

In some cases in the initial restoration of the beach, sand will
be added on private property landward of the property holding line.
The cost of this private'lot restoration would be the responsibility
of non-Federal interest. Also, land, easements, and rights-of-way,
are solely a non-Federal cost. When periodic beach nourishment is
considered as part of the most suitable and economical remedial
measure, and is construed as also fulfilling a construction role, it
is eligible for the same percentage of Federal aid as the initial
project construction cost. Five-year renourishment costs of $1,292,000
would be $496,100 Federal and $795,900 non-Federal. This amounts
to average annual equivalent charge of $85,200 Federal cost and $136,700
Federal.

In addition to other non-Federal cost, application of President
Carter's new cost sharing policy results in the State of South Carolina
paying a cash contribution of five percent of initial project cost.
This five percent front-end loading is estimated at $119,600 for the
recommended project. Cost apportionment for the recommended project
is shown in Table 11.

Rev.
28 Mar 80
35

FEDERAL RESPONSIBILITIES

The presently estimated Federal share o; the total first cost of
the Folly Beach project is $722,500. The Federal Government is responsible
for the preparation of plans and specifications and for construction of the
project. The estimated Federal share of 5-year renourishment operations
cost is $496,100 and of the average annual cost for post construction, pro-
ject monitoring is $1,400.

NON-FEDERAL RESPONSIBILITIES

The presently estimated non-Federal share of the total first cost
of the proposed project is $1,670,500. In addition, the non-Federal
interests must share in the renourishment cost in the amount of $795,900
each five years and must provide the non-Federal share of the project
monitoring program, $2,300 for each year of the 50-year project life
after construction. The local sponsor must also meet the local cooperation
requirements as outlined in the section entitled "Recommendations."

Plan Implementation

The steps necessary to provide a restored beach, with periodic
renourishment at Folly Beach .can be summarized as follows:

Review of the report by such higher authorities as the Corps
of Engineers' South Atlantic Division, the Board of Engineers for Rivers
and Harbors, and the Office of the Chief of Engineers.

After his review, the Chief of Engineers will seek formal review
and comment by the Governor of South Carolina and interested Federal
agencies.

Rev.
28 Mar 80
36

Following the above state and interagency review, the final report
of the Chief of Engineers would be forwarded to the Secretary of the Army
for further review and coordination with the Bureau of the Budget regarding
the relationship of tee project to the program of the President. He would
then forward the report, with his recommendations, to the Congress.

Congressional authorization for construction of the proposed project
would then be required.

After funding, a Phase I Report would be prepared to confirm, update,
and revise, when necessary, the original feasibility analysis.

Assuming no significant changes or controversies, design would
continue with the preparation of the Phase II Report, and any required
feature design memoranda.

If the Congress appropriates the necessary initial funds, formal
assurances of local cooperation would be requested from non-Federal
interests.

Plans, specifications, and an engineering estimate of cost
would then be prepared by the District Engineer, bids invited, and a
contract awarded. At th is time, the necessary local actions, including
,payment of the cash contribution, would be required.

Following completion of initial construction of the project,
local interests would b�e responsible for overseeing public use of the
beach and appropriate for making contributions toward beach renourishment,
when appropriate.

It is not possible to accurately estimate a schedule for the
above'steps. However, once the project is authorized and initially
funded, it is possible to complete design and construction in about
two and one-half years if subsequent appropriations are forthcoming

37 Rev
6 Nov 79 0

as needed. Actual construction is expected to take less than a year
and would probably be accomplished during the off-season to minimize
effects on the tourist trade.

Views of Non-Federal Interest
The considered plans of improvement were coordinated with various
state, local and non-governmental interests. Coordination was also made
in the form of three public meetings held in Folly Beach on 8 March 1976,
29 November 1977, and 7 December 1978. Statements by those interests
are contained in Appendix 3. Complete transcripts of the public meeting
are in the files of the Charleston District office.

Review by Other Federal Agencies

Letters and comments received from other Federal agencies are
contained in Appendix 3.

Statement of Findings
The documents concerning the proposed action and the stated views
of other interested agencies and concerned public have been reviewed
and ev aluated in light of the overall public interest, relative to the
,various practicable alternatives in providing the needed erosion control
protection and recreation opportunities at Folly Beach. The possible
consequences of plan alternatives have been studied according to en-
vironmental, social well-being, and economic effects, including regional
and national development and engineering feasibility. In evaluation, the
following points were considered pertinent:

The project would p rovide an adequate degree of erosion protectionS
for the affected areas.

The selected plan has strong local support, however, the source of
local funding may be a problem in light of the high non-Federal cost.

Care was taken in the design of the project to minimize adverse
environmental effects, and to mitigate, where possible, for those ad-
verse environmental effects which could not be avoided. The selected
project produces net environmental gains for the project area.

The project-is sized close to the optimum economic capacity,
is functionally adequate and economically justified.

Recreational aspects of the project are economically justified
and are desired by the local people.

In addition to the above, the following table summarizes signifi-
cant impacts of alternative plans and is considered pertinent to the
selection and evaluation of the selected plan.

The proposed action, as developed in the "Formulating a Plan"
and "The Selected Plan" sections, is based on thorough analysis and
evaluation of various practicable alternative courses of action for
achieving the stated objective. The selected plan is consonant with
national policy, statutes, and administrative directives, and the total
public interest should best be served by implementation of the selected
plan.

RecomniendatiDNS

It is recommended that the selected plan described in this report be
authorized for construction as a Federal project for beach erosion
control, with such modifications as in the discretion of the Chief of
Engineers may be advisable, at a first cost to the United States presently
estimated at $772,500 exclusive of the cost of preauthorization studies
with an annual renourishment participation cost presently estimated at
$85,200 and post construction, beach monitoring cost sharing of $1,400
'annually. These costs are exclusive of amounts to be contributed by
non-Federal interests prior to construction and for subsequent renourish-
ment; such local contribu'tions are identified separately in this report.
The exact amount of Federal and non-Federal contributions shall be
determined by the Chief of Engineers prior to project construction, in
accordance with the local cooperation requirements.

It is further recommended that if the project is authorized for
construction and local interests construct useful portions of the
project prior to the availability of Federal funds, the local interests
be reimbursed or credited for the Federal share of the work performed by
them on the project. This reimbursement or credit for local expenditure,
upon Federal funds becoming available, would be contingent upon-approval
of the work by the Chief of Engineers as being in accordance with the
*aut horized project prior to commencement of work on detailed plans and
specifications and arrangements for the prosecution of the work. The
amount-of reimbursement or credit would be based on a determination of
the reduction in cost of the Federal project resulting from local
interest's work, such determination to be made at the time of the
Federal construction. Payment would be based on the lesser of either
the unit cost under the Federal contract or actual cost.

~~~~~~~~~~~~40
40 ~~~~~~~~~~Rev.
28 Mar 1980

TABLE 12 - SUMMARY SYSTEM OF ACCOUNTS

(FOR EXPLANATION OF ABBREVIATIONS, SEE NOTES AT END OF TABLE)
Pt.-AN A-a (RECORIIENSEE) I PUFRN A-4 (RUE) F L A B j A_~ I(Q) RELOCATION OF STRUCTURES (to 11988)
A. PLno RSCRIPTEON REACH DEVELOPMENT PLAN RECSSVLPEE RN50 BSEACH DEVELOPMENT PLAN RO-TU-RLUA
STA 244-700 TO OTA 1431-RON STA 7EI-705S.TO STA 1804-RO ST 78+701 NT 10-RETA7+010STRU100+00
S. EICNSFICANTC IMPACTS

fta Esthetic Value ... AT-EL a.AT-EL a. AT-EL - " R

Ab. Manmde Re....rce h. AL h. AL h. AL 6. so.

c.Natural ReSOURceS c AT-EL . AT-EL ~.AT-EL A

Ad. Natac Quality d. AT d. AT d. AT d.M

A6. Air QualIty a. AL a. AL a. AL.

Af. Noise i. AL 1. AL. A. AL A

2..Scil 2. Social 2. Social 2. Social 2. Social

a.C-nity Cohesion a. L a, EL 8. L .A

-h. Coseity Oroth b. AN h.E EN N .AL

c... Rcetional Ootuieao. IL AL AL 0. ALa

Ad. Riepl ms of P",Pl. end Cc-uity d. N 8. N d. N d. AT
Diaropt Eon
3. Ohe - .Eft. 3 O t e tss.ff t 3. Other REcnmic Effocta 3. Other Ec..o-i. Effects 3. Other Beconomi EFfects

*,Ten Revenuce a. AL a ELa. L
~~~~~~~~~~~~~~~~~~~~~~~~~~~~ALl. AL
*6. Property Val..a . E~L h. EL b. EL h. AL

A Publlc Pecilities c. L c. AL o. EL -.AL

A.Public Service d. EL d. EL d. EL d.RN

c.Regional Groweth . 0. M S. N

e.~~~~~~~~~~~A EN S. RN

Ag. ssisesa acd led. Activity S. BEN .E E S. AL

C. PLAN EVALUATION

I. Contrihutlcn to Plsaniog Objectives S.Cootrihutios to Fla-nnig Ohjentivei

a. frosion Control A. L (lees thes A-4 or ES) a. L (greater then &-S, lose than E-1) a. L Igreter then A-C or A-4) a.M

b. Renreanosal Ee...h h. AL (less than A-A or E-l) h. EL (greater than. A I, ie... thon n-1) h. AL (greater than A.-0 or A-A) 6. AL

c.Hurricane Prntettion 0. N-L c. EN-L AL AL.

d. Toucis~t BE...d Econoy d. AL (loes tha A-.4 or E-) d. EL (greater them A-1, loeg E-1) d. AL (grester than A-C or A-A) d. AL

2. Relatiomehip te four National Accounts 2. fleltisoehip to Four National Acconn

a. NED M. No

(1 3Enflcial (Annua Es.efit.)
(a) Erosion Control -$29003304,000 $ 304.080

Ct) Recreation, 681,500 7060 12g,900
(C) Hurricane Wave Eamge 0 1.0
(dy Total Prevention -9.0 $ 1,064,600 - $,055,ooo- $ Tl100
(2) Adeere. (Anoma Cherge.)
$ 256.400
()Interest and Asortination 9 SE,700 $700.300

(h) Operation, and H.Iainanase 225.600 7,03910
$ 534,200 01,009,400 $ 73,300 A
c)Tntal $407,300

(3) A/C Rattio 1.2 2010 .

Cl) Seethes AT AT AT AN

- a~~~~~(2) Veter Quality AT-ELAT

(3) Recreation AT-EL IT3.A-LA
j~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~x .Ioct 79.

Provided that non-Federal interests will:

a. Provide without cost to the United States all necessary lands,
easements, rights-of-way and relocations required for construction of the
project, including that required for periodic nourishment;

b. H.old and save the United States free from claims for damages
which may result from construction and subsequent maintenance of the
project, except damages due to the fault or negligence of the United
States or its contractors;

c. Assure continued conditions of public ownership and use of the
shore upon which the amount of Federal participation is based during
the 50-year economic life of the project;

d. Assure maintenance and repair, and local share of periodic beach
nourishment during the economic life of the project as required to serve
the intended purposes;

e. Provide and maintain necessary access roads, parking areas, and
other public use facilities, open and available to all on equal terms;

f. Provide any appurtenant facilities required for realization
of recreational benefits;

g. Comply with the provisions of the Uniform Relocation Assistance
and Real Property Acquisition Policies Act of 1970 (Public Law 91-646);

h. Comply with Title VI of the Civil Rights Act of 1964 (PL 88-352);

1I. Establish prior to construction a property "hold line", which
will separate publicfrom private property when beach restoration projects
are constructed; and

j. Provide a cash contribution for beach erosion control, including
periodic nourishment for the 50-year project life, equal to the percentage

41 Rev.
17 Oct 79

TABLE 12 - SUMMARY SYSTEM OF ACCOUNTS (CONT'D)

PLAN A-0 HC~vEUI PLAN A-4 (NED)I PLANRB-I tEDl RELOCATION OF STRUCTURES (EDI 11960) 3
-- - R~~~~~~~~~~~~~~~~~~EACH DEVELOPMENT PLAN BEACH DEVELOPMENT PLAN - DUNE ANDs BEACH DEVELOFMNUI PEAN RN -STRUCTURAL PLAN
SEA 241-705 To STA 143+19O0 5fT 781755 TO STA 18104SA 8-0T EA10-U SA7+0 O T StI
C. PL.ANI4RAS.OTION -- - - 78+7 TO ST. 1809. ST -70 OSA 8
2. Relations.hip to Four NecL.iolAcut
*b. EQ (Coot'd)

*(4) 'Bath. ti.. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~b. EQ (.ooE'd)
*(A) *tstheiits ~~~~~~~~~~AT-EL AT-RE AT-BL L)~

-(S) Aft 9SUUY AL A L ALa

-(6) Noise . (5) N

(6)

d. S~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~DC. N
D. PLAN RESPONSE TO ASROCIATRD EVAISIATION CRITERIAANRamd

1.AceOptability Above A-A or 8-1 because of Iloe Ioa ...Ists r. Above E-U but I... than A-U because of osI ...Ioa.t, Loss than A-H and A-A becanos of loca ...... I. Lo-n respocoIve to desires.

2. Certainty B ~ ~ ~ ~~~eath eroion end -recetion needs partially sot knb .roic he..sa d -esre.nisseeds partially sE. Bosch etos.s and R-acrejoc oeds partally ott 2. Beanch erosion and rhecroatonseed oat _tot

.Cop.pteenoee All staies to echbe1- plan arc Ostludod. All staep to acheivo pi.. are Ancldd All stopsE achetVe Plan are Ocdd.3. All atop. to achieve plan are Ocoludod.

A. 'Zffoc~ivseaes- Ranks thIrd of focal pi.... Rooksatonend of final Plane. Rocks first of final pla... 4. Bank, fourth af ficol plan..

S. Equicy Rc.-fit. 5ot5prbcorly witblc study Ores. R Bo..fit. c- prinrily, within study arcs. Beflte tn priaarily, withic stndy area.5.Ctiucrscbc

6. Rsveroibilicy Ca. be Lrecovered by ntE eaoainLinig. Can h. revered by not aananCrcan bo toversad hi eat naitaicog. 8 0 LIe.. thnthec 8-Iota

7. StabilIty Stable it properly naintaonod. Stable If properly nointeiced. S t ahle if properly naitauiood.7.SbeOfPoelnaracd

8. 650 Rscefkt/Csst latin ~~~~~~ ~~2.1 . 1.0 8.1.1

E. IMPLEMENTATION RESPONSIBSIITY

I. First Cost

t a. Poderel $ 771,200 91.021,700 l.,094, 1003

b. B.c-Federl1 1,782.800 !2.579,300 4,73l,9001/

c. Total $2,554,000 03.801,000 19,826.000

2. AnnealI Charge

a. ederal $ lIo.U00 P184,700 uO A06O00Y 586600

b. 257-Pd2rs 349.5006880!

_14.700
0.Total $407,300 -$534,200 12,009.400,$7,0
~~~~~~~~~~~~~~~~~~~~~------- -- $7,D

KINOTESE a- Reneftckel 1qinat

A- Adverse SincE

P - INntal lm.tep

T T-Teporary

L -Long Teen

*Slgeifftant Imacts specified In Sectjno t021e4 FL 91-811

I/ Coat sharo8 ...uld -t be apoted by BsPera"Wie s' t - tonsIoko Benefit Hotbed ab.. tho orcs c~sc ofcost L. ..t ecneoaly stified.
-s were -hared4 acsind. done coat will be shies 20-3 (Fad-co-Fed) and the ...st for beoh ouohdlwih protects the doan .ill be shared the sans as oh beach delp tpIs.".

5 ]Best sac-flood Plain alteOntovel esIettad andiretted by Flond Plain Ifngeaoer Reecatino Order N.. 11988.

- lasted bene.fit' fr' the 'lmCso of eaeted etouctoral 1oaa.. free St-- aend besbersh c

f Etsatwed sa relnosie 259 endangerLed etowite ...n.d content. Esaeree fr.. sits. . --17Ot7
550051@ Ecu~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~R.

of the construction cost allocated to this function exclusive of lands,
easements, rights-of-way, private fills, alterations and relocations,
the percentage to be in accordance with existing law based on shore
ownership and'use existing at the time of construction, which contribution
is presently estimated at $1,670.500 or 69.8 percent of the total first
cost of the proposed project and $795.900 or 61.6 percent of the 5-year
renouri'shment cost and $2,300 or 61.6 percent for each year of the
monitoring program after construction. Non-Federal construction cost
estimates includes a five percent state contribution of the construction
cost.

.k. The President, in his June 1978 water policy message to Congress,
proposed several changes in cost-sharing for water resource projects to
allow states to participate more actively in project implementation decisions.
These changes include a cash contribution from benefiting states of five
percent of construction (first) costs associated with non~-vendible outputs
and 10 percent of costs associated with vendible outputs.

Application of this policy to the Folly Beach project requires a cash
contribution from the state of $119,600 of an estimated $2,393,000
(five percent of $2,393,000 total estimated first costs of construction
assigned to non-vendible project purposes, based on April 1979 price levels).
This contribution is in addition to other items of local cooperation usually
required for shore projects including'cost participation based on shore
ownership and use. The total non-Federal first cost would be $1,670,500.
I recommend construction authorization for the Folly Beach project in
accordance with the President's proposed cost-sharing policy.

WILLIAM W. BROWN
Colonel, Corps of Engineers
District Engineer

Rev.
42 ISZ Mar 80