Inlet hazard areas the final report and recommendations, by the North Carolina Division of Marine Fisheries, Technical Services Section, to the Coastal Resources Commission of the the [sic] North Carolina Department of Natural Resources and Community Development

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

COASTAL ZOINE
INFORMATION CENTER

INLET HAZARD AREAS

'j fp
U;
b 1i L L E lua 9 H

THE F1 NAL REPORT AND RECOMMENDATIONS

THE COASTAL RESOURCES COMMISSION

We J. Priddy and Rick Carraway

Technical Services Section,

GB@ Division of Marine Fisheries
454
.154 North Carolina Department of Natural Resources@and Community Development
P74
1978

September'1978

-INLET HAZARD AREAS

THE FINAL REPORT AND RECOMMENDATIONS
BY
0 THE NORTH CAROLINA DIVISION OF MARINE FISHERIES
TECHNICAL SERVICES SECTION

THE COASTAL RESOURCES COMMISSION
OF THE
THE NORTH CAROLINA DEPARTMENT OF NATURAL RESOURCES
AND
COMMUNITY DEVELOPMENT

North Carolina Department of Natural
Resources &Community Development
44- James B. Kint, Jr., Govemor Howard N. Lee, Secretary
0

Loie J. Priddy
Rick Carraway

September 1978

CONTENTS

OBJECTIVES I

USEFUL DEFINITIONS 2

PROCEDURES 3
Photography sources 3
Scaling 3
Gridding 3
Measurements 3
Statistics 4
Other methods 4
Final plotting 4
Final comments 4

RESULTS AND RECOMMENDATIONS 5
Oregon Inlet 6
Hatteras Inlet 8
Ocracoke Inlet 10
Drum Inlet 12
Bardens Inlet 14
Beaufort Inlet 16
Bogtie Inlet 18
Bear Inlet 20
Browns Inlet 22
New River Inlet 24
New Topsail Inlet 26
Old Topsail Inlet 28
Rich Inlet 30
Mason Inlet 32
Masonborc, Inlet 34
Carolina Beach Inlet 36
New Inlet 38
Cape Fear Inlet .40
Lockwoods Folly Inlet 42
Shallotte Inlet 44
Tubbs Inlet 46
Mad Inlet 48
Little River Inlet 50

OBJECTIVES

The prime objective of the agreement between the Division of Marine Fisheries
and the Coastal Resources Commission was as follows:

"The Division will develop and apply a Commission approved method for
the identification and delineation of hazard areas adjacent to e xisting inlets for
use by the Comrrilssion in designating Inlet Lands AEC's in the Vicinity of
inlets.

This prime objective was broken down in the agreement into two requirements:

A "one huxired percent of the inlets will be completed during the current contract
period.

COMMENTS ..... North Carolina's twenty-three classic inlets may be cate-
gorized as exempt and non- exempt. Exempt inlets include thos e inlets bounded
by federal lands. (See North Carolina Coastal Plan, Appendix "Ell). These in-
lets include Oregon, Hatteras, Ocracoke, New Drum, the west side of Bear,
Browns, and the east side of New River. Beaufort, Masonboro, and the north.
side of Oregon are specifically exempted as "stabilized" inlets in State Guide-
lines for Areas of Environmental Concern, Technical Appendix 3, Section.0900,
Paragraph .0901.

The eastern shoreline of Little River Inlet, although classed as a non-exempt
inlet, hasmigrated over one -thousand feet into South Carolina in recent years
and should not be presently considered as a North Carolina inlet. Details of its
territory and trends are included, however, since it may still be an influence.

Although the lands around Bardens Inlet are presently under condemnation for
inclusion in the Cape Lookout National Seashore, they are still not technically
federal lands, so it is considered non-,exempt for this report.

All twenty-three of North Carolina's inlets, including so-called ".exempt" and
''stabilized" inlets, have been completed at this time.

B "The Division. shall draft on photo-base mylars supplied by the OCM a line
representing the.extent of AEC boundaries on all inlets, using the approved
procedure.

COMMENTS ..... The extent of the recommended inlet hazard area boundary has
been drafted for all inlets on the photo-base blueprints (not mylars) supplied for
that purpose. It,is recommended that plotting on the expensive photo-base mylars
be done after the hazard area recommendations are accepted by the Commission.

USEFUL DEFINITIONS

LINEAR REGRESSION The mathematical technique of determining the most
likely relationship between an independent and a dependent variable, assuming
the variables to be related as first-degree polynomials of the form:
Y= nX+C

QUADRATIC REGRESSION The mathematical technique of determining the most
likely relationship between an independent and a dependent variable, assuming
the @,ariables to be related as second-degree polynomials of the form:
Y= nlxz+nX+C

It is. important to remember that, regardless of true data tendencies, a linear
regression will always yield a straight line relationship between variables., and
a quadratic regression will always yield a parabolic relationship between var-
iables. For example, if a stone is thrown into the air, physical laws cause its
,path to form a parabola. If measurements were made of the path of the stone,
and-Ahis data was regressed linearly, a true but inaccurate linear regression
would be the result. The type of regression selected is of ultimate importance
tothe accuracy of the results.

CUBIC, QUARTIC, ETC. Third and fourth degree polynomials of the forms-
Y= kX3+mXz+n,X+C
y= jX4+kX3+rnX?-+nX+C .. .... etc.

TRANSCENDENTAL, CYCLIC Equations containing an infinite number of alge-
braic operations ( Y=logX, Y= ex, etc. Some transcendentals may repeat
over and over and are thus cyclic ( Y=: sinX, Y= cosX, etc.

CONFIDENCE INTERVAL The limits of a dependent variable between which. a given
percentage of values will probably occur for a given independent variable. In
this report, a 99% probability within a 10 year projection is used. In other words,
there should be only 1 chance out of 100 that any one segment of shoreline will
exceed the designated hazard area at any time within the next 10 years.

X FIELD The range of values of X, (independent variable) used in a regression.

-2-

PROCEDURES

Photography sources

All commercially available photography which met scale and coverage require-
ments and was readily obtainable was identified and catalogued by DMF , then
purchased by CRC. In addition to this photography purchased by CRC, various
non-commercial photographs taken or held by DMF, as well as some photogra#is
held by private individuals, @xere used to generate a stronger data base. 862rces
included the National Ocean Survey, the- U. S. Dept. of Agriculture, the U. S.
Geological Survey, the National Archives, the N. C. Department of Transport-
ation, the N. C. Division of Marine Fisheries, and others.

Scaling

A geographically stationary control system was established for each inlet or
inlet complex so that an accurate scale 'fGr each photograph of Ahe.. inlet could
be established. Control systems for four inlets were carefully established us-
ing published photo- identifiable geodetic control stations. The absolute scales
thus obtained were independently compared to the 1977 DOT photo-base blue-
prints. The results were so consistently accurate on these four inlets that the
.1977 DOT scaled (1"= 400') photography has been accepted as the base control,
and othe r photo-series are being scaled from it with only random.. checking.
Frequently photographs from the ASCS approached the accuracy of the DOT
photography.

Gridding

Using the pre-viously determined scale in conjuction with identifiable photo -
points, a geographically stationary grid system in the vicinity of each inlet or
inlet complex was established. This grid system was oriented parallel to the
predominant ocean shoreline to facilitate the detection of any lateral mavem@
of the inlet's shoreline. A grid spacing of 300 feet was selected as providing
adequate resolution of an inlet's gyrations.

Measurements

To prevent confusion, inlet shorelines were referred to as "left" and "right",
As seen when facing the inlet from the ocean, rather than as 11 north shorelindl,
"southwest shoreline", etc. Measurements were made to the hundredth of an
inch from a stationary zero point on the grid system to the estimated high
water mark. 'Then, using the previously calculated scales, the measurements
were converted to feet and tabulated for each grid on the photograph. Station
000 (zero) of the grid system is always on the right side of the inlet and mea-
surements increase to the left. This technique simplifies the time' series
graphing of both sides of the inlet simultaneously.

-3-

Statistics

The left and right sides of each inlet were treated separately and individual in-
let grids were regressed both linearly and quadraticaliy to determine the best
fit trends of the inlet. On accepted curve fits, the landwardmost 9916 confid7
ence interval projected to occur between 1978 and 1988 on a given grid was
made to represent the limit of the inlet hazard area'on that grid. A few inlets
displayed apparent higher degree or complex transcendental movement, so some
fits were rejected on these inlets for other methods. Due to the narrow forty
year X-field of the data, some quadratic fits on shorelines showing wide sho@t-
term excursions had to be rejected as meaningless. Multiple throats, channel
stabilization projects, and shoreline stabilization projects frequently interfere
with the -regression process, and some fits were rejected because of the ekst-
ence of one or more of these.

Other methods

When inlets or grids did not conform to attempted regression methods, strong
emphasis was placed on previous inlet territory, as determined by relict inlet
ridge locations. The methods used are described by John J. Fisher in his tw'o
papers, 'Geomorphic Expression of Former Inlets Along the Outer Banks of
North Carolina, 1962, and Development Patterns of Relict Beach Ridges, Out-
er Banks Barrier Chain, North Carolina, 1967. Document.ed historic locations,
and'structurally weak areas near the inlet were also considered in determin-
ation of the limits of the hazard areas.

Final plotting

Points established according to the methods described , above were then con-
nected from grid to grid on the photo-base blueprints, thus, generating the final
Inlet Hazard Zone. It is recommended that in no instance should the final In-let
Hazard Area be less than an extension of the adjacent Ocean HazardArea. Since
the Ocean Hazard Area was not delineated on the photo-base blueprints suppliecl
DMF did not determine instances where this situation actually occurs; however,
the Inlet Hazard Zones shown on the blueprints should be reviewed and modifie4
if necessary, to indicate the approved Inlet Hazard Area.

Final Comments Concerning the Statistical Analysis of Inlet Movement

Time and lack of a sophisticated computer limited the complexit y of calculations
so, for this report, only-basic linear and quadratic regressions were examined.
But, this severely limits a total regression analysis because any inlet is thie pro-
duct of many complex factors and is not necessarily polynomial in form. Ifithe
statistical process is to be fully utilized in the future, inlet movement should also
be examined for higher order polynomials, cyclic or trancendental patterns.-i and
methods of time-series forecasting applied. Even so, common sense and good
judgement remain as important tools in establishing Inlet Hazard Areas.

-4-

RESULTS AND RECOMMENDATIONS

OREGONINLET

feet Typical movement (#12L & 14R)
12000-

10000- left side

8000-

right side
60 00

4000

2000-

0'. 0 U 0 u7v 0 u 9 I-TTTTIST .......1
40 50 0 0 0 u u6V U 0 0 0 88

year

INLET HAZARD AREA RECOMMENDATIONS

OREGONINLET

Photographs used; 20 Typical grid is 12, 13, 14

NOTES:
Channel maintained regularly. This has a stabilizing effect on both shore-
lines though neither shoreline has major groin or jetty stabilization. Mainten-
ance must be continued to protect Oregon Inlet Bridge. Inlet opened during
storm in 1846 and has a history of continuous southward migration since. then.
Photo data suggests that, except for a wide excursion of the right shoreline
between 1955 and 197 1, the inlet as a whole has been quadratic in nature since
1940 (6500/1940;7700/1960;8000/1977). The relatively slow southward drift
since 1960 probably reflects the increased channel stabilization following the
construction of the bridge in 1962.

LEFT SIDE RIGHT SIDE

Undeveloped, low development poten- Undeveloped, low development poten-
tial. tial.

Federal land, Cape Hatteras National Federal land, Cape Hatteras National
Seashore. Seashore.

Regresses quadratically, little move- Wide excursion (6000-1000-6000) be-
ment since 1962. tween 1955 and 1971 negates normally
used regression methods.
Channel stabilization interference.
Channel stabilization interference.
Recommend extension of ocean hazard
line. Recommend extension of oceanhazard
line.

NOTE: NORTH SIDE OF INLET CON-
SIDERED STABILIZED. EXCLUDED
FROM REQUIREMENTS. ( N. C.
COASTAL PLAN;. Nov., 1977).

NOTE: ENTIRE INLET FEDERAL LANDS. SPECIFICALLY EXCLUDED

FROM REQUIREMENTS. (N. C. COASTAL PLAN; APPENDIX E; Nov., 1977).

-7-

HATTERASINLET

feet Typical movement (#16)
24000-

20000:

15000- left s ide

side channel

10000-

main channel

5000

right side

0`11 1 1 1 11
40 50 6101111 70 80 88

year

-8-

INLET HAZARD AREA RECOMMENDATIONS

HATTERAS INLET

Photographs used: 23 Typical grid is #16(L);13(R)

NOTES:
Naturally navigable; inside channels dredged No shoreline stabilization. In-
let opened by a storm in 1846. Ridge data indicates a wide territory ( 3000 -
21500). Photographic data since 1.943 reveals a westward drift of about 3700
feet. Secondary channel. broke through left of main channel around 1955, twin
channels existed until around 1962 when the two channels merged. In addition,
several less significant channels have existed at various times since 1943.

LEFT SIDE RIGHT SIDE

Undeveloped, low development poten- Undeveloped, low development poten-
tial. tial.

Federal lands, Cape Hatteras Nation- Federal lands, Cape Hatteras Nation-
al Seashore.. ;@l Seashore.

Multiple channels make regression Regression data does not provide ade-
questionable. quate protection considering overwash
action in the area.
Regression data does not provide ad-
equate protection considering over- Recommended line as shown on map.
wash action in the area.

Recommended line as shown on map.

NOTE: ENTIRE INLET FEDERAL LANDS. SPECIFICALLY EXCLUDED

FROM REQUIREMENTS. (N. C. COASTAL PLAN; APPENDIX E; Nov., 1977).

-9-

4 F f P F 91

OCRAC'OKEINLET

-feet Typical movement (#25L & 7R)
30COO

left side
25000
2000o.1
right side

15000-

10000

50
01
A
DI FTT-rT II I I I I I I, II I I is I I- 111111 111 11
-T@40 50 '7 80 88

year

-10-

INLET.HAZARD AREA RECOMMENDATIONS

OCRACOKE INLET

Photographs used: 17 Ty,,ical grid is #25(L);7(R)

NOTES:
Naturally navigable prehistoric inlet. No shoreline stabilization but very
stable with little tendency to migrate. Ridge data indicates a slow movement
to the southwest. Photographic data since 1943 reveals that the right side has
drifted southwest about 3000 feet. The left side has moved 1000 feet or less and
the intertidal shoal. on the left side seems to absorb most of this activity so that
the shoreline further inside near Portsmouth village is almost stationary.

LEFT SIDE RIGHT SIDE

Undeveloped, low develo,,ment potential Undeveloped, low development potential.

Federal lands, Cape Look out National Federal lands, Cape Hatteras National
Seashore Seashore.

Fits linear regression extremely.well Good linear fit.

Recommend extension of Ocean Hazard Low overwa,sh area to about 8000.
Area.
Recommend extension of Ocean Hazard,
Area.

NOTE: ENTIRE INLET'FEDERAL LANDS. SPECIFICALLY EXCLUDED

FROM REQUIREMENTS. (N. C. COASTAL PLAN;; APPENDIX E; Nov., 1977).

_Vf

DRUMINLET

feet
12000-

1000(r Typical movement 2)

8000-

60('0-

left side
4000.

2000-1

- right side

40 50 60 70 80 88

year

INLET HAZARD AREA RECOMMENDATIONS

DRUMINLET

Photographs used; 6 + opening date Typical grid is 2

NOTES:
Artificially opened December 23, 1971 just south of natural location
of former Drum Inlet. Original cut was 2001 wide; inlet' widened rapidly
to over 30601. Channel and sound inside of inlet are shoaling extensively.
This inlet has not existed long enough to establish a true statistical fit.
Drum Inlet will probably continue to widen and shoal even more, though
its rate of widening has slowed since the rapid rate shown in its first few
years of existence. It is possible that, without extensive dredging, the
throat of the inlet may become so shallow that the inlet will dose or be-
come a wide 11swash" like other former inlet sites in the vicinity.

LEFT S I DE RIGHT SIDE

Undeveloped; low development Minor past development, low
potential. future development potential.

Federal land; Cape Lookout Nat- Federalland; Cape Lookout
ional Seashore National Seashore.

No valid statistics due to short No valid statistics due to short
time of existence. time of existence

Recommend extension of Ocean Low overwash areas and very
Hazard Area. narrow barrier island extending
northward past the old location
of Drum Inlet.

Recommend extension of 'Ocean
Hazard Area

NOTE: ENTIRE INLET FEDERAL LANDS. SPECIFICALLY EXCLUDED

FROM REQUIREMENTS. (N. C. COASTAL PLAN; APPEDIX E; Nov., 1977)

-13

E LOOXOVT

C
'APr
LOOKW, I'

BARDENSINLET

f eet Typical movement (#12)
6000

5000

4000

3000
left side

2000

1000

right side
0
40 50 60 70, 80 88

year

-14-

INLEI HAZARD AREA RECOMMENDATIONS

BARDENSINLET

Photographs used: 28 Typical grid is 12

NOTES:
Navigable channel maintained by dredging, no shoreline stabilization.
Present inlet opened around 1933 to a depth of 5 feet and a width of 50 feet.
Mainly overwash area prior to that time. At first glance, the inlet appears
to have migrated cast about 700 feet since its opening; but closer examinaiion
reveals that the left shoreline has remained within a few hundred feet of its
original location while the rigit shoreline has migrated eastward in excess of
1500 feet. This movement regresses quadriatically with a rapid rate from
'1943-1964 and a much slower rate from 1964-1976, see below.

LEFT SIDE RIGHT SIDE

Undeveloped, no land access, very low Undeveloped, no land access, very
development potential. low development potential.

Under condemnation by the National Parts under. condemnation by the
Park Service to become federal lands. National Park Service to become
federalland.s.
Recommended line as shown on map.
Movement rate has increased
since 1976 and, if it continues, may
require re-evaluation of data.

Recommended line as shown on map.

NOTE: PORTIONS OF THIS INLET ARE NOW AND MOST SOON WILL

BE EXCLUDED FROM REQUIREMENTS. (N. C. COASTAL PLAN; APPENDIX

E Nov., 1977).

@V .... ..

MURRY

fit'

0@1

BEAUFORTINLET-

f ee.t Typical m ovement (#17)
12000-

left side

10000-

8000
60 00 maintained channel r igh@ t s ide

400.0 side
channel

2000-

year
j
side
channel

INLET HAZARD AREARECOMMENDATIONS

BEAUFORTINLET

Photographs used: 32 Typical grid is 17 -18

NOTES:
Seaport channel regularly maintained in same location since before 1952.
Serves as outlet for Newport and North Rivers. Itis thoughtthat a former
location may have been further east near the western end of Harkers Island,
but it has M*aintained a relatively narrow territory for the past 156 years.
Post-1938 photo data suggests a westward migration tendency that has, been
almost totally interrupted by extensive jettying on the right. shoreline and ex-
tensive channelization. This interruption negates regression of either side.

LEFT SIDE RIGHT SIDE

Undeveloped, state owned, Fort Macon Undeveloped, under condemnation
State Park. Low development potential. to be federal lands by National Park
Stabilized by extensive jetty s and groins. Service
Some groins from 000 to 2500.
Stabilization interference, not regressed.
40001+ westward migration since
No hazard line established. 1938.

Recommend extension of ocean hazard Migration arrested by maintained
line. channel.

Channel inte rf er enc e, not regressed.

Recommended line as shown on map.

NOTE: ENTIRE INLET SPECIFICALLY EXCLUDEDFROM REQUIRE-

MENTS. (N. C. COASTAL PLAN Nov. 1977).

-17-

-
V
V

rWR -CW

-BOGUEINLET

feet Typical movement (#5)
12000-

10000

8000 left side

6000

40GO

2000
right side
07 T47 IT
III UVOII10 0 @@p 1061OUT 70 80 88

year

-18-

INLET HAZARD AREA. RECOMMENDATIONS.

BOGUE INLET

Photographs used: 21 Typical grid is 5

NOTES:
Pre-historic inlet occasionally maintained by dredging. Data since 1'871
reveals the inlet to be subject to frequent, possibly cyclic, large scale excur-
sions within its historic territory. It forms the mouth of the White Oak River
and no significant migration is to be expected. Data since 1938 shows an
unusual eastward movement of more than 3000 feet; possibly indicating the
downwar d swing of the cyclic pattern menti'oned above.

LEFT SIDE RIGHT SIDE

No development, low development Moderate development, high development
potential. potential.

State lands,Hammocks Beach State Moderate problems associated with erosion,
,Park development events since 1971.

Excurs ions. to 12000 since 1938 Minor stabilization attempts since 1973.

Configuration makes regression Shoreline is presently farther east. than
validi ty doubtful. at any time in recent history.

Recommended line as shown on map. Configuration makes regression validity
doubtful.

Recommended line as shown on map

_t9_

NM46

A, Beikfii@,
j@ommoc

Soco

Isle

BEARINLET

feet Typical movement (#4)
120.00-

10000-

8000-

6000-

40('0- left side

2000- right side

0.
40 50 60 70 80 88

year

-20-

INLETHAZARD.-AREA R ECO1\4MENDAT IONS

@BEAR INLET

Photographs used: 15 Typical grid is 4

NOTES:
Mi nor- inlet but very stable with strong regression data. The only
instability of note in the area was the historical existence of nearby
Sandy Inlet at about 11, 0 0 0

LEFT SIDE RIGHT SIDE

No development, federal lands, very low No development, low development
development potential. potential

Camp Lejeune Marine Base Hammock Beach State Park

Recommended line as shown on map. Recommended line as shown on map

NOTE: FEDERAL LANDS SPECIFIC-
ALLY EXCLUDED FROM REQUIRE-
MENTS. (N. C. COASTAL PLAN;
APPENDIX E; Nov. 1977).

-21-

oft

6000

BROWNS INLET

feet Typical movement (#2)
120,00-

10000-

8000

6000

left side

4000-
right side

2000-
01
40 50 60 70 80 88

year

-22-

INLET HAZARD AREA: RECOMMENDATIONS

BROWNS INLET

Photographs used:-19 Typical grid is 2

NOTES:
Minor, stable inlet providing good regression data. This inlet has moved
very slowlywestward since 1938@but it accelerated slightly between 1958 and
1972. Total movement s,ince 1938 is about 1000 feet.

LEFT SIDE RIGHT SIDE

No development, federal lands, very low development potential (both sides).

Camp Le jeune Marine Base (b oth sides).

Recommended lines as shown on map.

NOTE: FEDERAL LANDS SPECIFICALLY EXCLUDED FROM REQUIREMENTS
(N. C. COASTAL PLAN; APPENDIX E; Nov. 1977).

-23-

4;@
41
ay

:7@9.

NEW RIVER INLET

12000 f eet Typical movernent (#10)

10000:

8000

left side
6000
4000 right side

'2000

o"11
410111111' AII'VIIIIIJAIII11#117411 I I I III 18Y 88

year

-24-

INLET HAZARD AREA RECOMMENDATIONS

NEW RIVER INLET

Photographs used: 24 Typical grid is 10 and 11

NOTES:
Navigable channel maintained by dredging but throat is subject tofrequent,
unpredictable, medium scale excursions within its historic territory. Evidence
of some long-term cyclic trends is apparent. Since it serves aB an outlet for
New River, no great migration is to be expected away from the vicinity of the
mouth of this river.

LEFT SIDE RIGHT SIDE

Under development, moderate to Undeveloped, federal lands, very, low.
high development potential. development potential.

Ridge format ion& indicate activity to Camp Lejeune Marine Base.
about 7600.
Ridge formations indicate activity to
Quadratic regression exaggerates pre- about I 100.
diction patterns because of cyclic trends.
Regressions distorted because of is-
Recommended line as shown on rnap. land (grids 11-12/1900-3800);.

Recommended line as shown on map.

NOTE: FEDERAL LANDS SPECIFIC-
ALLY EXCLUDED FROM REQUIRE-
MENTS. (N.C. COASTAL PLAN;
APPENDIX E; Nov. 1977).

-25-

Olt,

1: el,
511

NEW TOPSAIL INLET

feet Typical movement (#13),
9000

800,0
7000 left side
6000

5000

right side
4000

3000

2000

1000

40 @o Al 70 80 88

year

-Z6-

INLET HAZARD AREA RECOMMENDATIONS

NEW TOPSAIL INLET

Photographs used: 27 Typical grid is 13 and 14

NOTES:
Nav'i gable channel maintained by dredging, no major. stabilization. Data
.since 1938 suggests a cubic southward movement; however, closer examination
by means of triangulation station descriptions since 1914 reveals this apparent
cubic trend to be a part of either a quartic or higher order function or a com-
plex function consisting of a cyclic trancendental superimposed on another func-
tion. In any case, the result is a series of periods of rapid movement followed
by periods of little or no movement (- 1000 / 1914; 1800 /1933; 2300 /1948; 3900
1958; 5200/1977 Total southward movement 1938-1977:,3200 feet.

LEFT SIDE RIGHT SIDE

Undeveloped, no land access, moderate Medium development, high develop-
development potential. ment potential.

Complex movement makes normally Minor groin and dune stabilization
used regression methods questionable. on oc ean shoreline near inlet.

Recommended line as shown on map. Long feeder channel to the north
would seem to make a breakthrough
in that direction likely.

Finger channels in banks at 2000
create a vulnerable area.

Ridge data indicates northern terri-
tory to be -3400.

Complex movement and above con-
ditions make normally used regres-
sion methods questionable.

Recommended line as shown on map.

-27-

OLD TOPSAIL, INLET

18090 feet Typical movement (#14)

17000

16000

15000 left side

14000-
right side
13000-

1200G-

11000 -

10000-

9000.
I I I I 15- 1oil
4'0 50 60 70 80 88

year

INLET H AZARD AREA R ECOMMENTIONS

OLD TOPSAIL INLET

Photographs used: 28, Typical grid is 14

NOTES:
No maintained channel, no stabilization. Statistics suggest southward mig-
ration following a roughly cubic equation since 1938 (remained steady at 11200
from 1938-1950; increased rapidly from 11200-13500 between 1950-1966 -slowed
considerably between 1966-1977from 13500-14300). Total movement southward
was 3100 feet, 1938-1977. Ridge data indicates present position to be slightly
further, south than at any time in recent history. Inlet position may alternate be-
tween major channels at 9000 and 17000.

LEFT SIDE RIGHT SIDE

Undeveloped, no land access,moderate Undeveloped, no land access, moderate
development potential. development potential.

Cubic southward drift negates normally Cubic southward drift negates norm-
used regression methods. ally used regression methods.

Recommended line as shown on map. Recommended line as shown on map.

_29-

RICH INLET

feet Typical movernent (#10),
35000-

340'00-

3,3000-

32000 left side
31000 J

30000- right side

219000-

Z8000

27000-

26000
40 50 60 70 80 88

year

-30-

INLET HAZARD AREA RECOM%4ENDATIONS

RICH INLET

Photographs used: 32 Typical grid is 10 and 11

NOTES:
No.maintained channel, no stabilization. Migrated 1200 feet southward since
1938. Ridge formations suggest that the inlet is presently at its southern limit of
travel in recent history, that its territory is somewhat restricted possibly due to
the intermittent historical existence of nearby Sidburry Inlet (Little Topsail) at
23000, and that the ocean shoreline on the left side of the inlet has accreted
nearly 1000 feet.

LEFT SIDE RIGHT SIDE

Little development, high develop- Undeveloped, no land access, moderate
ment potential. development potential.

Steady sou thward drift since 1938. Predominant drift is southward; move-
ment is erratic.
Recommended line as shown on map.
Recommended line as shown on map.

-31-

'14

1-4

atet
Masoa z

VV sed)
t (C,10
A Moore Iate

(U
r-T I T-7-7--r-v I I1 -1

0 0 0 CD 0 0 0 C)
0 0 C 0 0 0 0 0
0 C) CD 0 0 0 C5 0
0@ 00 110 U') cn

NLET HAZARD AREA RECOMMENDATIONS

MASONINLET

Photographs. used: 28 Typical grid is 10 and I I

NOTES:
No maintained channel, no stabilization. Migrated 3000 feet southward be-
tween 1945 and 1963 but has drifted slowly no rthwa rd since (2100,/1945,;5400/
1963; 5100/1977), creating a quadratic or higher order statistical condition.
Dune ridge territory is not definable.

LEFT SIDE RIGHT SIDE

Undeveloped, high development potential. Moderate development, high develop-
ment potential.
Some overwashing past 9000.
If quadratic statistical trend is valid,
Recommended line as shown on map. substantial property loss may occur.

F
inger channels in banks at 1300 and
3400 create a vulnerable area.

Recommended line as shown'on map.

-33-

11 51

MA'SONBOROINLET

f eet Typical movement (#11)
.12000-p

-s ide
channel

60'00

left -Sid-e
'40.00 -
right @side

.2000.-

.0- -FTT M. I I go 00 1 o rou un numuo inuum vie i im re in
40 @O 60 70 80 88

year
Zh

-34-

INLET HAZARD AREA RECOMMENDATIONS-

MASONBOROINLET

Photographs used: 32 Typical grid is# 11

NOTES:
Channel maintained and considered stabilized. Insignificant movement since
1938 except for 4000 foot excursion on the left . side between 1945 and 1959
(5300-9300-4600). This excursion created a double throat between 1,951 and 1959,
not an uncommon occurence according to historical notes.

LEFT SIDE RIGHT SIDE

Extensive jetty planned for later in 1978. Shoreline recently approached 3100.

Stabilized-by extensive jetty.
Past multiple channels negate accurate
regression. Not regressed,jetty interference.

Shoreline approached 9200 during the No hazard. line established.
1950S.
Intense development to near capacity.
Ridge formations indicate activity to about
9400. Recommend extension of ocean hazard
line.
Presently undeveloped, proposed Mason-
boro Natural Area, low development pot.-
ential.

Recommended line as shown on map.

NOTE: ENTIRE INLET SPECIFICALLY EXCLUDED FROM REQUIRE -
MENTS. (N. C. COASTAL PLAN Nov. 1977).

-35-

71
;M-

--------- -
CD
"73

CAROLINA BEA-CH INLET

feet Typical movement (#9)
120.00-

10000.4

80.001-

6000-' left side

4000 right side
5:1S id-e
- channel
2000-,

0 11 1111111111.1191 1 a II-quillp IM@ U11 11 OPP 11 rTTTTM
40 50 60 70 8'0 88.

year

-36-

INLET HAZARD AREA RECOMMENDATIONS

CAROLINA BEACH INLET

Photographs used: 25+opening date Typical grid is 9

NOTES:
Opened by private interests on or about September 15, 1952. Double throat
existed up to and including grid 10 during mid-fiffies. Almost no migration ten-
dencies. Navigable channel existing.

LEFT SIDE RIGHT SIDE

Undeveloped, moderate to high devel- Undeveloped, proposed Masonboro
opment potential. Island Natural Area,.low development
potential.
Frequent overwashes to 13000.
Frequent overwashes to 0,00 a,ndbeyond.
Recomi-riended line as shown on map.
Recommended line as shown on map.

-37-

@ mm@, -

poc ks

0 09

-.--ro--'F UAE
%S Am 35r*,Oo
J;7

NEW INLET

f eet Typical movement 2)

- I eft @s-ide
150'00-
right side

10000-

50@00

0-1 will I T I 1 1111
'Al 1 1 1 5 1 116lot I a 1 1 t I I @10 8 C', M.

-38-

INLET HAZARD AREA RECOMMENDATIONS,

NEWINLET

Photographs used: 32 Typical grid is 2

NOTES:
Minor unstable inlet having the highest migration rate of all North
Carolina inlets (14, 000 feet in 30 years). The present-day inlet is a part
of a complex inlet/washover system extending from -2000 to 35, 000.
Since 1938, -this system has included other inlets at 800, 5000, 8200,
18000, and 27000. According to triangulation station descriptions, the
ocean shoreline in the vicinity has migrated westward as much as 2600
feet since 18.53. Alone, New Inlet data yields a reasonably sou'nd linear
regression, but the entire system should be considered extremely volatile.

LEFT SIDE RIGHT SIDE

Undeveloped, low development potential Undeveloped, low development potential.

State lands (part of a recent agreement May be state lands-,boundary uncertain.
between the state and Carolina Cape Fear
Corporation. Low, narrow overwa'sh area to -2000

Low, narrow overwash area to 35, 000 Recommended line as shown on map.

Recommended line as shown on map.

-39-

4@,

1- rzek

CAPE FEAR INLET

feet typical mo-vement (t@2,91,;#-25R)
12'000

100010-

8000

left side

6000

4000

2000 -
r'Lght side

0
40 50 60 7 0' 80 8'8'

Y eZi r -

INLET HAZARD AREA RECOMMENDATIONS

CAPE FEAR INLET

Photographs usedl 23 Typical grid is #29L;25R

NOTES:
Prehistoric navigable inlet forming the mouth of the Cape Fear River.
Very stable but'navigation depths are maintained by dredg@ng. Little movement
since, 1938. little movement expected in future.

LEFT SIDE RIGHT SIDE

Some development., n-ioderate develop- Some development, high development
ryient potential. potential.

ReCommended line as shown on map Recommended line as shown on map

-41-

)*1'a '71_71@_, 'i

LOCKWOOD FOLLYINLET

-feet Typical movement (#I I)
12000-

10.0 0 G-

,H 0
0,_

.6000,m

left side
4000.':

right--side
.2000 '.m

0
4o 50 60 70 80 88

y@ea,r

-42.-

INLET HAZARD AREA RECOMMENDATIONS

LOCKWOOD FOLLY INLET

Photographs used: 28 Typical grid is 11 and 12

NOTES:
Navigable channel maintained by dredging. Inlet serves as outlet for Lock-
wood Folly River. Presently, a 5000 foot offset between the river and the inlet
makes flanking via a new inlet breakthrough a definite possibility. This occurred
in 1954 at the -4800 lotation but was quickly filled in artificially. In spite of its
river outlet status,ridge cbLtaindcates a wide territory. Statistics indicate a
slight eastward migration,trend. Little movement since 1938.

LEFT SIDE RIGHT SIDE

Moderately developed, moderate to Moderately developed, moderate to
high development potential. high development potential.

Ridge formations indicate historic No ridge formations but known terri-
activity to about 9000. tory extends to -5000

Moderate losses due to ocean shore- Small scale shoreline protection groin
line encroachment near inlet. system built in early seventies.

RecomMended line as shown on map. Recommended line as shown on map.

-43-

i2v
6,

"N. p
"T,

0"0

SHALLOTTE'INLET

leet Typical movement (-#3L & &R)
12000

-10000

80,00 teft,side

6000 right side

ell,

40V

2000

0
.40 5 0 .,6( '76 .80 '&8

y ear

INLET HAZARD AREA RECOMMENDATIONS

SHALLOTTEINLET

Photographs used: 24 Typical grid is #6

NOTES:
Prehistoric navigable inlet serves as outlet for Shallotte. River.
Some westward movement from 1938 to 1950, and a slower drift west-
ward since then. The 4000 foot offset between the inlet and the river
makes flanking via a new inlet a possibility. - This occurred in 1954
at,the'1500 location (probably the former site of Bacon Inlet).

LEFT SIDE RIGHT SIDE

Moderately developed, Moderate to Light development; moderate to
high development potential. high development potential.

Ridge data indicates historic activity Ridge data indicates historic act-
to about 9000. ivity to about 1000.

Moderate excursions with moderate Moderate excursions.
erosion losses.
Recommended line as shown on
Recommended line as shown on map. map.

-45-

7 -,77
i, -x;

TUBBS- INLET

feet Typical. m.ovem- -ent Z-)
12,000--,

I GO 0,0

Artificially clo;s-e;d

8
-0
,00

@0.
6oo:

Artificially opened

40,010

Zo 0,0

0 .1111 11 1 111-171111 11 11:131 1 9 F I I 1. 9 W* I U 1. 1@ I. I II I. v r II I I I III
40 50, 60 70 &'G 8'&
year

-46-

INLET HAZARD AREA REC'OMMENDATIONS

TUBBSINLET

Photographs used: 26 Typical grid is 2

NOTES:
Insufficient data for statistical analysis. Old inlet location moved. about
3000 feet (5 500 to 8500) to the west from 1938 until it was closed artificially
in 1970. It was artificially reopened in another location (5000) a few months
later, and has widened with an apparent eastward drift since then.

LEFT SIDE RIGHT SIDE

Moderately developed; high development Light development; high devel-
potential. opment potential.

Insufficient statistical data. Insufficient statistical data.

Recommended line as shown on map. Recommended line as shown
on map.

-47-

12
C000
0#00

MADINLET

f eet Typical movement 4)
12000-

.10000-

8000

6000

4000
left side

right side
2000

40 50 60 70 80 88

year

-48-

INLET HAZARD AREA- RECOMMENDATIONS

MADINLET

Photos used: 23 Typical grid is #4

NOTES:
Minor,* unstable inlet; wide excursion since 1938 (500 to 5000) makes
statistical predictions weak. Inlet throat has narrowed from 1700 feet to
200 feet since 196o and the inlet may be subject to closing completely.

LEFT SIDE RIGHT SIDE

Undeveloped; moderate development Moderately developed; high
potential. development potential..

Weak statistical trends. Weak statistical trends.

'Recommended line as shown on map Recommended line as shown
on map..

-49-

@
4
CA

rig

/20ft
00"

LITTLE RIVER INLET (Right side only)

feet Typical movement (#Z)
1200.0-

10000- 1@4(@ /SC.BOUNDARY
. . . . . . . . . . .

80:00

6000

4000-1

2000-

40 50 60 7.0 80 88

year

-50-

INLET HAZARD AREA RECOMMENDATIONS

LITTLE RIVER INLET (Right side only)

Photos used: 23 Typical grid is #2

NOTES:
Prehistoric, navigable inlet forms m outh of Little River. Generally
accepted as a rough- border between North and South Carolina,. however
migration trends since 1955 have moved the entire inlet well into South
Carolina.

LEFT SIDE RIGHT SIDE

In, South Carolina Undeveloped; moderate
development potential.

Shoreline presently in S. C'.

Recommended line as shown

on map.

-51-

APPENDIX

MEMORANDUM OF AGREEMENT

Involved Agencies: Office of Coastal Management
Division of Marine Fisheries
Coastal Resources Commission

Purpose

This is an agreement between the Office of Coastal Manage-
Merit (OCM) which provides primary staff support to the North
Carolina Coastal Resources Commission (herein called the
COMISSION) and the N. C. Division of Marine Fisheries Re-
search and Management Section and Graphic Services Section
(herein called the DIVISION), engaging tile Division to perform
certain duties as outlined herein relative to developing a
methodology or methodologies for delineation of ocean hazard areas

and applying this methodology to existing North Carolina inlets
in order to establish the boundaries of areas of environmental

concern.

Contract Period

This agrement shall cover the period from July 1, 1977 to
February 28, 1978.

Authority

The North Carolina Coastal Area Management Act (hereinafter
referred to as CAMA), was enacted in 1974 by the N. C. General

Assembly to bring resource planning and management to the coastal
area. A major portion of funding for implementation of CAMA was
provided through the Federal Coastal Zone Management Act of 1972.
The CAMA established a "Coastal Resources Commission" and dele-
gated to the Commission the authority to establish certain "Areas
of Environmental Concern" (herein referred to as AECs) as well
as regulatory authority over these AECs once they are established.
Tho AECs are intetided to identify critical areas in the coastal
irca that because of nature connote some special manage-
trient technique of land use control within this area.

Problem

Due to the lack of detailed information about inlets with
regard to their potential to adjacent development, the
Commission finds it useful to obtain more information arid develop
specific techniques for identifyinig hazard areas adjacent to inlets.

0bjective

The Division will develop and apply a Commission approved
method for the identification and delincation of hazard areas
adjacent to existing inlets for use by the Commission in Designat-
ing Inlet Lands AECs in the vicinity of inlets.

FY 1977-78

A. After the decision has been made by the Commission as
to what method is most desirable, the Division would
initiate application of the appropriate technique in
establishing AEC boundaries on all inlets. Sixty per-
cent of the inlets will be completed during the current
contract period. It is expected that all the inlets
will be completed by June 30, 1978.

B. The Division shail draft on photobase mylars supplied
by t8he OCM a line representing the extent of AEC bound-
aries on all inlets using the approved procedure.

ESTIMATED BUDGET

FY 1976-77

a Salaries and Fringe Benefits $5,500

b. Photographic, drafting, and
graphic materials (for in-house
darkroom) 900

C. Aircraft,time 300

d. Travel 200

e. Statistical Consultant @ $20/hr. (2 1/2 hrs.) 50

Project Totals $7,OOO

Conditions

The DiviSion hereby agrees to abide by all provisions and
conditions of NOAA Grant #04-6-158-44095, which is made a part
hereof by reference and is attached.

Ownership of all equipment purchased pursuant to this agree-
ment, including photography and map cabinets, will be retained
by the OCM.
Quarterly performance reports will be submitted by the
Division to the OCM for inclusion in the CZM program report to
NOAA.

Continuation of this Agreement past February 28, 1978 is
dependent upon the availability of adequate funds in the approved
coastal zone management budget to support the described project.

MEMORANDUM OF AGREEMENT

Involved Agencies: Office of Coastal Management
Division of Marine Fisheries
Coastal Resources Commission

Purpose

This is an agreement between the Office of Coastal Management (OCM)
which provides primary staff support to the North Carolina Coastal Re-
sources Commission (herein called the COMMISSION), and the N. C. Division
of Marine Fisheries, Research and Management Section and Graphic Services
Section (herein called the DIVISION), engaging the Division to perform
certain duties as outlined herein relative to developing a methodology or
methodologies for delineation of ocean hazard areas and applying this
methodology to existing North Carolina inlets in order to establish the
boundaries of areas of enviornmental concern.

Contract Period

This agreement shall cover the period from March 1, 1978, to August
30, 1978.

Authority

The North Carolina Coastal Area Management Act (hereinafter referred
to as CAMA), was enacted in 1974 by the N. C. General Assembly to bring
resource planning and management to the coastal area. A major portion of
funding for implementation of CAMA was provided through the Federal
Coastal Zone Management Act of 1972. The 'CAMA established a "Coastal
Resources Commission" and delegated to the Commission the authority to
establish certain "Areas of Environmental Concern" (herein referred to as
AECs) as well as regulatory authority over these AECs once they are
established. The AECs are intended to identify critical areas in the
coastal area that, because of their nature, connote some special
management technique of land use control within this area.

Problem

Due to the lack of detailed information about inlets with regard to
their hazardous potential to adjacent development, the 6ommission finds
it useful to obtain more information and develop specific techniques for
identifying hazard areas adjacent to inlets.

Objective

The Division will develop and apply a Commission approved method for
the identification and delineation of hazard areas adjacent to existing
inlets for use by the Commission in designating Inlet Lands AECs in the
vicinity of inlets.

FY 1977-78

A. After the decision has been made by the Commission as to what
method is most desirable, the Division would initiate applica-
tion of the appropriate technique in establishing AEC
boundaries on all inlets. One hundred percent of the inlets
will be completed during the current contract period. It is
expected that the inlets will be completed by August 30, 1978.

B. The Division shall draft. on photobase mylars supplied by the OCM
.a line representing the extent of AEC boundaries on-all inlets
using the approved procedure.

ESTIMATED BUDGET

FY 1977-78.

a. Salaries and Fringe Benefits $ 3,600

b. Photographic, drafting, and graphic
materials (for in-house darkroom) 900

C. Aircraft time .300

d. Travel .200

Project Totals $ 5,000

Con ditions

The Division hereby agrees to abide by all provisions and conditions
of NOAA Grant #04-7-158-44094, which is made a part hereof by reference
and is attached.

Ownership of all equipment purchased pursuant to this. agreement, in-
eluding photography and map cabinets, will be retained by the OCM.

Quarterly performance reports will be submitted by the Division to
the OCM for inclusion in the CZM program report to NOAA.

An individual identifying program number shall be set up in the De-,
partmental, Accounting System to account for expenditures under this Memo-
randum 'of Agreement with appropriate backup receipts. Any portion of the
project total unaccounted for on August 30, 1978 shall be forfeited by the
Division of Marine Fisheries and no work may be funded after this date.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement
as of the day of ,1978.

THE DEPARTMENT OF NATURAL OFFICE OF COASTAL MANAGEMENT
RESOURCES AND COMMUNITY
DEVELOPMENT, FOR THE STATE
OF NORTH CAROLINA

Contracting Officer Contracting Officer
Deputy Director Executive Secretary
Division of Marine Fisheries Coastal Resources Commission

Approved by
Approved by
Department of Natural Resources Department of Natural Resources
and Community Development and Commanity Developoment
Witness Witness

@7,
11INIIIIIINVI
-1 3 6668 14101 4375 ,