survey of North Carolina beach erosion by air photo methods, 1973

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

The Center for Marine and Coastal Studies North Carolina State University

Coastal Zone
Information AUG a 1914
Center
A SURVEY OF NORTH CAROLINA
BEACH EROSION BY AIR PHOTO METHODS
1973

By
H. E. WAHLS CDAItM L-
INF2MApON CENTER

REPORT NO. 73-1
MAY, 1973

GB
4 59.4
%.1

.W33 I
1 973

CASTAL ZON
|NEE~uRSOFIgTER

A SURVEY OF NORTH CAROLINA
BEACH EROSION BY AIR PHOTO METHODS
1973

H. E. Wahls'
Professor of Civil Engineering

U. S. DEPARTMENT OF COMMERCE NOAA
COASTAL SERVICES CENTER
2234 SOUTH HOBSON AVENUE
CHARLESTON, SC 29405-2413

Property of CSC Librazy

Report No. 73-1
Project ERSD-464

Center for Marine and Coastal Studies
North Carolina State University
Raleigh, N. C.

May 1973

PROPERTY OF THE
UNITED STATES GOVERNMENT
NATiONAL OCEANIC AND
ATMOSPHERIC ADMINiSTRATION

For Re;enlion
When no longer needed, please
return to: Technical Processes
Branch - D-23

ACKNOWLEDGMENTS

This project was supported jointly by the Division of Waterways and Sea-

shores, Office of Water and Air Resources, Department of Natural and Economic Re-

sources, State of North Carolina and the Center for Marine and Coastal Studies,

North Carolina State University. The cooperation of Col. R. J. B. Page, Chief',

and Dr. L. J. Langfelder, Director, of these respective agencies is acknowledged.

Negatives of the aerial photographs for November, 1971, were made avail-

able by the U. S. Army Coastal Engineering Research Center, Washington, D. C.

Prints were obtained from these negatives through the cooperation of the Photo-

grammetry Section, North Carolina State Highway Commission.

The detailed measurements and computations of erosion data were per-

formed by Mr. Ralph Gordon, graduate assistant in civil engineering. Dr. Donald

B. Stafford, Clemson University, who conducted the original 1968 study, assisted

by providing useful advice and information at the start of the investigation

TABLE OF CONTENTS

Page

List of Figures.............................. iv

Introduction ...............................1

Methodology. ..............................2

Summary of Results............................ 5

References. ...............................6

LIST OF FIGURES

Figure Page

I-i. Index map of sections used for presentation of erosion data 7

1. Brunswick County
(a) Dune line and high water line. Composite mean annual rates of 8
change (feet per year) 1938-1972.

(b) Dune line and high water line. Mean annual rates of change 9
(feet per year) for most recent time interval, 1966-1972.

(d) High water line. Mean annual rates of change (feet per year) 11
for previous time intervals.

2. New Hanover and Pender Counties
(a) Dune line and high water line. Composite mean annual rates of 12
change (feet per year), 1938-1972.

(b) Dune line and high water line. Mean annual rates of change 13
(feet per year) for most recent time interval, 1966-1972.

(d) High water line. Mean annual rates of change (feet per year) 15
for previous time intervals.

3. Onslow and southern Carteret Counties
(a) Dune line and high water line. Composite mean annual rates of 16
change (feet per year), 1938-1971.

(b) Dune line and high water line. Mean annual rates of change 17
(feet per year) for most recent time interval, 1964-1971.

(d) High water line. Mean annual rates of change (feet per year) 19
for previous time intervals.

Figure Page

4. Eastern Carteret County
(a) Dune line and high water line. Composite mean annual rates of 20
change (feet per year), 1945-1971.

(b) Dune line and high water line. Mean annual rates of change 21
(feet per year) for most recent time interval , 1962-1971.

(d) High water line. Mean annual rates of change (feet per year) 23
for previous time intervals.

5. Hyde and southern Dare Counties
(a) Dune line and high water line. Composite mean annual rates of 24
change (feet per year), 1945-1971.

(b) Dune line and high water line. Mean annual rates of change 25
(feet per year) for most recent time interval, 1962-1971.

(d) High water line. Mean annual rates of change (feet per year) 27
for previous time intervals.

6. Northern Dare and Currituck Counties
(a) Dune line and high water line. Composite mean annual rates of 28
change (feet per year), 1949-1971.

(b) Dune line and high water line. Mean annual rates of change 29
(feet per year) for most recent time interval, 1962-1971.

(d) High water line. Mean annual rates of change (feet per 'year) 31
for previous time intervals.

I NTRODUCTION

A beach is a transient feature which is continually eroding or building

up as a result of the action of wind and waves. Knowledge of the patterns of

coastal erosion is essential to the safe and orderly development of a coastal

region. This is particularly true for coastal North Carolina which is currently

undergoing rapid development. If this development is allowed to proceed without

consideration of potential beach erosion, severe economic losses are likely to

be incurred by both private owners and the public.

An indication of the potential future erosion of a beach can be gained

from a study of the history of erosional patterns along that beach. Aerial photo-

graphs provide an ideal me ans for studying the erosional history of an area. Each

aerial photograph records the location of the beach, as well as related cultural

and natural features, at a specific time. Comparisons of the positions of the

shoreline in photos taken at different times will indicate the amount of erosion

for the time interval between the two photographs. Such investigations can be

conducted for any time periods fo-r which aerial photography is available.

Specific techniques for beach erosion studies from Aerial photograph's

were developed and applied to the North Carolina coast-by Stafford in 1968. The

results of this study were presented in the report, "A Reconnaissance of Coastal

Erosion in North Carolina", by Langfelder, Stafford, and Amein. Mean annual rates

of erosion and accretion were presented for the entire time period of available

photography and for each incremental time period between successive photo-S. For

the southern coast from Brunswick to Beaufort Inlet'. photography dating back to

1938 generally was available. North of Beaufort Inlet, the earliest available

photos were made in 1945, The date of the most recent photography used in that

investigation varied with the county and ranged from 1961 to 1966.

Because of the demonstrated value of the beach erosion data, in the sum-

mer of 1972, it was deemed advisable to update the survey. The work was jointly

sponsored by the Office of Water and Air Resources, Department of Natural and Eco-

nomic Resources of the State of North Carolina, and the Center for Marine and

Coastal Studies, North Cairolina State University. New aerial photographs were ob-

tained of the entire North Carolina coast. For Brunswick, New Hanover, and Pender

counties, excellent quality photos taken in January and February of 1972 were

available from the U. S. Department of Agriculture. For the remainder of the

coast, photos for November, 1971, were obtained from the U. S. Army Corps of Engi-

neers. These photos were generally of small scale and poorer quality than the

Department of Agriculture photos. Using these new photographs, the techniques of

the original study were employed to compute a new increment of erosion data for

the entire coast and to revise the data reported in the original study. Thus this

report includes the results of the original study as well as new data for the time

interval since the publication of the original report.

METHODOLOGY

The present study essentially used the methods presented by Langfelder,

Stafford, and Amein (1968), and elsewhere, but eliminated some measurements and

computations- which had not proven meaningful in the initial study. These techniques

and modifications will be reviewed briefly in the following paragraphs. In addition,

some of the limitations of the method will be indicated.

To determine the rate of erosion for a specific time interval , fixed

reference points, which can be clearly- identified in aerial photographs at both

the beginning and the end of the time period, were established at approximately

1000-foot intervals along the beach. Road intersections, utility poles, and cor-

ners of permanent structures were used as reference points. The distances from

each reference point to the dune line and the high water line were measured in

each photograph. The difference in the position of the dune line and the high

water line at the beginning and end of the time interval is the amount of erosion

or accretion during the interval. If the total change in position is divided by

length of the time inte rval in years, the average rate of erosion or accretion in

feet per year is obtained for the interval. This procedure was repeated at each

reference point for each time interval for which erosi~on rates were to be calculated.

The data for a series of reference points were averaged for specific

sections of beach between inlets or other locations for which significant changes

in erosional characteristics were anticipated. These mean annual rates of erosion

or accretion are reported for each section of beach for the new time interval for

which photography was available. The results for the new time interval were then

averaged with the results from the 1968 report to obtain a new composite mean an-

nual rate of erosion or accretion for the entire time interval of the original and

the new studies. All computations were done by~computer using the computer program

developed by Stafford for the original study.

The air photo method for measuring coastal erosion is limited by the

availability of aerial photographs, the quality of the available photographs, and

the ability of the interpreter to identify the position of the dune line and the

water line in the photographs. Relatively new photographs were available for the

entire coast for the current study. However, there was considerable variation in

the quality of the photographs. Excellent quality photographs were available for

Brunswick, New Hanover, and Pender counties. For these counties, rectified enlarge-

ments to a scale of I" = 400' were obtained. These enlargements have been corrected

for various photogrammetric errors so that the scale is accurate and uniform for all

photographs. For the remainder of the coast, the photographs were of poorer quality.

* ~The approximate scale of these photographs was I" = 1000" and the scales varied by

as much as 10% from one photograph to another. Smaller scale variations were pres-

4.
ent within an individual photograph because of the tilt of the camera. Finally,

the imagery was not always clear; and in a few photographs, the beach line was

partially obscured by cloud cover. Fortunately, all portions of the coast were

visible in at least one photograph.

Measurements on the individual photographs were made to the nearest

0.00l inches, using a patented microrule. However, the actual field distance

represented by the measurement on the photograph is significantly affected

by the reliability of the scale. For example, if the scale of the photograph is

1, = 1000' plus or minus 10%, a one inch distance on the photograph could repre-

sent a real distance of 900' to 1100'. Such variability was not acceptable and

the scale of each individual photograph was determined to a greater accuracy.

The scale of' individual photographs was established by measuring the distance

between the fixed reference points in the new photographs and relating this dis-

tance to the distance between the same points in a previous photo of known scale.

Human error is introduced by the need to interpret the position of the

dune line and the high water line. Usually the high water line can be identified

by the distinctive change in color tone. However, the dune line frequently was

subject to more interpretation. The dune line generally represents a point of

abrupt change in slope which can be observed best by using stereo pairs. In some

areas, the dune lines are very distinct, while in other areas, the dunes may have

been removed by development or the dunes may be quite low. In these cases, con-

siderable judgment was involved. In all cases, the position of the dune li ne in

the new photograph was compared with the position in the earlier photographs to

minimize errors due to differences in interpretation of the dune line by different

individuals.

SUMMARY OF RESULTS

The significant results of the new study are combined with the

results of the original study and presented in Figures l-6, For pur-

poses of presentation, the coast has been divided into six sections

which are indicated on the index map in Figure I-1, Section I starts at

the South Carolina line and succeeding sections progress northward

with Section 6 ending at the Virginia line.

All results for each section are presented together in a series

of four figures, For example, the results for Section l, Brunswick

County, are presented in Figures I-a, b, c and d. Figure 1-a presents

the composite data for the entire period of both studies, 1938 - 1972.

Mean annual rates of erosion or accretion, in feet per year, are pre-

sented for both the dune line' and the high water line, Figure 1-b

presents the mean annual rates of erosion-or accretion, in feet per

year, for both the dune line and the high water line for the time

interval of the new study, 1966-1972, for Brunswick County. Figures

1-c and 1-d are reprinted from the original 1968 report. Figure !-c

presents the data for the dune line for' each time increment between

successive photographs which were used in the original study. Figure

!-d shows similar data for each time interval for the high water line.

A similar set of 4 figures is presented for each of the six

sections of the coast line. All results are presented in units of feet

per year of erosion or accretion for the time intervals specified on

the figures. In Figures 3b, 4b, 5b and 6b, the data for the most

recent time interval are composites of the results of the new study

and the data for the most recent time interval of the original study.

This was done to minimize potential effects of the poor quality of the

new aerial photographs, which were used for these sections,

The first figure for each section, e. g., Figure I-a, for Brunswick

County, provides the best indication of long term erosion or accretion

trends. The second figure of each set, e. g., Figure 1-b for Brunswick

County, can be compared with the first figure of the set to determine

whether the behavior for the most recent time interval is significantly

different from the long-term average for the section. The third and

fourth figures of each set provide additional historical data on the

consistency of the erosion or accretion patterns at a specific location.

Finally, it should be noted that the data presented in this report

are indicative of long-term trends. However, short-term effects of

severe storms are not indicated. Such short-terms effects could be

studied by aerial photography if sufficient aerial photographs were

available, This could be accomplished by having aerial photographs of

the coast line made on an annual basis during a non-storm period.

These photographs would provide base data on long-term trends, such as

have been presented in this report, When the effect of an individual

severe storm is to be studied, another set of aerial photographs would

be made Immediately after the storm and compared with the existing base

photos. The monitoring of coastal'erosion patterns on an annual basis

would seem to be a highly desirable project for those agencies con-

cerned with the control and the protection of the coastal regions.

REFERENCES

1. Langfelder, L. J., Stafford, D. B., and Amein, M. (1960). "A

Reconnaissance of Coastal Erosion in North Carolina", Re-

search Project ERD-238, Dept, of Civil Engineering, North

Carolina State University, Raleigh, N. C,

2. Stafford, 0. B. (1968). "Development and Evaluation of a Procedure

for Using Aerial Photographs to Conduct a Survey of Coastal

Erosion", Unpublished Ph.D. thesis, North Carolina State

Universitv Ralpinh N �

]2 czi2 <~ ~ ~ Section 5

, -A2/

ection 4

X Section 3

s Section 2

Figure -1. Index map of sections used for presentation of erosion data.

Figure I-1. Index map of sections used for presentation of erosion data.

SCALE:' 1 inch= 8 miles
BRUNSWICK COUNTY
J.'

SOUTH ~
CAROL INA

Ve 3'V f / '

0,re

~change (feet peFerry) 1938-1972.

FiCaswell.Brunswick County
Cornca k e

/p~~~~~~~ ~ ~~ ,~,~

~~~ ~~~~~b~~~~,e''b~ ~ ~ ~ ~ ~ ~ O

SCALE: 1 inch= B miles
BRUNSWICK COUNTY

SOUTH
CAROLINA

lo,

Figure 1. Brunswick County
(b) Dune line and high water line. Mean annual rates of change
(feet per year) for most recent time interval, 1966-1972.
3~~~~ 9 1 n ~~~~~~~~~~~ ~~~~ I / 9`~~~~~~~L

SCALE: l inch= 8 miles
BRUNSWICK COUNTY

SO U TH Do b. .
CAROLINA Z

'Pja?� /

Figure 1. Brunswick County
previous time intervals.

Figure 1. Brunswick County

SCALE: I inch=8 miles
BRUNSWICK COUNTY

SOUTH 0,
CAROLINA /

. "o,

,.%.
" _---~O" 1'"

IFort
/sw.,, '.
I ~~~~~~ Cornca ke o~~.~
'o�I 41�~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~4

Figure 1. Brunswick County
(d) High water line. Mean annual rates of change (feet per year)
for previous time intervals.

NEW HANOVER COUNTY
SCALE: 1 inch = 8 miles
'Wi lmington tw I
/t SrF "-'"'~, I| . PENDER COUNTY

.- a

Dune� 3.6 .Erosion
Dune 0 / / - , , ............ : 3 1 -0.1''
Line 9.1 2.4 1.2 3.7 5.0 0.1
_ | ~~~~~~~~Accretion

11: . ~~~~4 ~~Erosion
High k /11IM - 53 ? 77 -0.5 1

LineI Accretion
5.5 3.4 $. 7 1.2

1 938- I
- 1960 _ 1938- 1972 Data
Data I

Figure 2. New Hanover and Pender Counties
(a) Dune line and high water line. Composite mean annual rates of
change (feet per year), 1938-1972.

ix,

NEW HANOVER COUNTY
SCALE: 1 inch= 8 miles
AW jilmington ,

+ adz 9 �-S %.. I\,. PENDER COUNTY

Liu~ne 5_ 9

ccErion

Figure 2. New Hanover and Pender Counties
b Dune line and high water line. Mean annual rates of change

(feet per year) for most recent time 1-17. -4.572.
Fater~igure 2.//~ New Hanover ruAccPnerie
Line --n ]h.9

ir~.n.~~

NEW HANOVER COUNTY
SCALE: 1 inch= Bmiles
"Wilmington
ffi / By>/-iz PENDER COUNTY

19So -6 5 Erosion

1496 83 2. 6 11 ' 04 5 0.4 AccrtEion

1938 - - Erosion
19496 - - 41 '
n 10r0 10 13 00 3 8creton

Figure 2. New Hanover and Pender Counties
previous time intervals.
1960- Dat a -0.1 Erosion
1966

Accretion

1956- Erosion
1960 1.3 -1.9 0.9
8.3 2.6 11.8 0.4 7.1 6

198-Erson

Figure 2. New Hanover and Pender Counties
(c) Dune line. Mean annual rates of change (feet per year) for
previous time intervals.

SCALE: 1 inch = 8miles NEW HANOVER COUNTY
f~ Wilmington L'

%� if �^ PENDER COUNTY

I196 - - /

Noq- - a -_ N Erosion
rData 20 2.2
196 0 -
3.1 15.4 17.4 1.5 1.1 Accrtion

1956- 61
1S-- "'A Erosion
1960 -
- | ~ 4. ~2 ~ 5.3 1.5 8.3 4.7 6.5 253 2.6 -09 Accretion.

1949 - -3 7 - 2 -8 7 Erosion
1956 -3.7 -2.2 -8 7 3
14.9 12.4 14.8 6 0.3 52 Accretion

1938 - o
1949 i- 1 411
11.7 3.9 2.4 2.7 4.4 5.5 4.4 Accretion

Figure 2. New Hanover and Pender Counties
(d) High water line. Mean annual rates of change (feet per year)
for previous time intervals.

SCALE: I inch = 8 miles

ONSLOW COUNTY CARTERET COUNTY

oly Ridge G 6/e,'reSi � ~�9v i Jsl'

_.in . . . ................... w ................ L . 7 Erosion
Dune 77 7 , - -41 / -7
Line 3.9 1.0 4.0 3.8 0.8 2.8 9.7 0.9 0.7 4.1 3.1 2.9 2.8 5.2 1.6 0.6
Accretion

Water10/////// g~ -26~~~ 777^~~~~~~77 LErosion
Hig h 0. 22.0 124 5.4 4.3
Water 777,777/ 77,;
Line 3.3 0.0 2.6 4.6 1.8 12.4 5.4 42.3 4.5 96 6.4 7.0

_._I~j~~~ i zo ~~Accretion
1953- 1958- 1953-
_938-1i D a t a 1938-1971 Data - 1971 1971 Dat 1938-1971 Data 1971
1938- 971 Data I -Data Data Data

Figure 3. Onslow and southern Carteret Counties
(a) Dune line and high water line. Composite mean annual rates of
change (feet per year), 1938-1971

SCALE: 1 inch = 8 miles

ONSLOW COUNTY CARTERET COUNTY

Erosion

Li~ne 7.4 . I 4.5 2.5 3.1 5,1 4.8 6.2
Accretion

High -7.2 Eoi
Water -- 05 -0.3 -2 l,877777
Line 4.0 07 2.2 8.3 6.1 0.4 0.8 2 6.2 1.6 2
Accretion

1960-1971 Data 1958-1971 Data

Figure 3. Onslow and southern Carteret Counties
(b) Dune line and high water line. Mean annual rates of change
(feet per year) for most recent time interval, 1958-1971
-5

SCALE: 1 inch = 8 miles

R ONSLOW COUNTY CARTERET COUNTY

meC~6ure -

9/ 1 - -1. y
B

oe E- rnErosion
-y Ridge Datah

196- ___11.9 9.7 12.2 201 10.8 157 103
6r -

previous time intervals.tion

No Erosion
1953- Data
47.9 10 2 -.9.9 . 5.9 .7 17.3
1949-
11.9 9.7 12.2 2 0.1 10.8 15.7 1' .3
No No No Erosion

1938- - 1.7 - -0.4 - 2.2 -4.8 Accretion
1949 mm.2
0. 2 26 .6 7.--"--2

SCALE: 1 inch = 8 miles

ONSLOW COUNTy
ONSLOW COUNTY CARTERET COUNTY

B B-clue

I .8 15 Eion
196 - UE
u LEJEU Data = at

1949 AccIncre-on
1958- -I.6

3.2 2.9 5.2 6.2 9.7
196for previous time intervals.
2.8 0.8 0.0 9 .3 1 .5 3.4
Erosion

19586 -
23.5 9.2 0.1 3.4 9.2 6.0 5.0 20.0
1956 -0.9 ~ccrctAon
5.8 2 .8 . 9 .6. 4

1939- D ata Data - Data

1938- 16.5 11.1 9.7 3. 2 4.9 18.0 8.7
1949 WOMMOW - &--.a4.6 Accretion
3.2 2. 9 5.2 6.2 9.7

for previous time intervals.

CARTERET COUNTY Cedar 'tJ

SCALE: I inch =8 miles Dh'rs/"/,� n '( ?-.A D

CORE Atlantic
SOUND / rtsmouth , HYDE
_ C " COUNTY
C -- -a pAens CORE BANK'S / Ocracoke
Inlet Inlet

Lookout D

Dune '// 'X777 Erosion
Dune -.3-3-5.7 -4.6 -5.3 / 77 /77777~7 -32.5
Line ____ ___ ___ ___ ____ ___ ___ 17.7 3.0 6.8 1.7

Accretion

Higieh ~ //~. %// g g , X < Erosion

Water
Line 5.3 6.3 6.1 10.8 10.2 13.9 8.1 6.8 4.7 0.7

Accretion
1945 -
1971
Data 1955- 1971 Data 1945- 1971 Data

Figure 4. Eastern Carteret County
(a) Dune line and high water line. Composite mean annual rates of
change (feet per year), 1945-1971.

Mr
o

Cedar
CARTERET COUNTY Islar Pe

SCALE: I inch = 8 miles At

CO RE SOUND HYDE
C SOUND mj~ - .~ COUNTY
C ~~- C ad~ens CCORE BAK c oA
fIflet /r/ R'r Eo tB A N K SInlet
Cape b
Lookout

Dune 7 7,,//, //77 -23.7 -23.6 -47.7
Line 3.8 3.4 2.4 7.0 7.3 5.5
Accretion

High -1.8 4 38.8
Water 13.5 103 92 17.2 24.5 14.1 0.9
Accretion

1960-1971 Data

Figure 4. Eastern Carteret County
(b) Dune line and high water line. Mean annual rates of charge
(feet per year) for most recent time interval, 1960-1971.

CARTERET COUNTY Island

SCALE: 1 inch = 8 miles .

CORA t lan tic P HYDE
~CORE ~ SOUND COUNTY
- C BANKS N Ocracoke
IC B ens COARE /, Inlet
Cope e o
Lookout

Incre -
ment I

1960 -
1965 - - _ _

=CO%= '"Erosion
1960-
1962
44.1 37.3 67.9 69.7 58.0 47.6 41.7 188.6 191.0
Accretion
Erosion
1958- -13.4 -8.4 -0.3 -36.6 -56.5 -9.0 0.8 - 39.4 -62.9
1960
Accretion

1955-
1960 _
11.7

No Erosion

-9A.11 - 4.319Erosion
1955- - 9 417.3 -. f195
19581955 -

14.1 6.2 5.3 26.7 18.5 Accretion

Figure 4. Eastern Carteret County
(c) Dune line. Mean annual rates of change (feet per year) for
previous time intervals.

CARTERET COUNTY Cedar
Island P

SCALE: I inch = 8 miles . D

CORE tlantic PortsO I HYDE
C SOUND mo-th
C _D _ --) COUNTY
C-- aIens CORE O BANKS ' >/ Ocracoke
Cape '~
Lookout O
Incre -
mont

1960- -14.1
1965

1960- Ers
1962
38.4 17.6 10.0 62.9 111. 91.9 42.6 0.4 0.8Er ion
Accretion
1956S8- ~ ~ 7 1 -1 6 Erosion

246 _ 15-Accretion

1958-

1960 4 - - 1.

1955 8= -56~1 -DaNDota Erosion
26.0 42~7 162 74 _ 27 278 7.1
Accretion
1 , ,

14-194S5 1- nErosion
.1 Accretion

1955 19-_
23 46N9 20E5 369 36 01 A ion

Figure 4. Eastern Carteret County
(d) High water line. Mean annual rates of change (feet per year)
for previous time intervals.

SCALE I inch =8 miles

HYDE COUNTY ~~~DARE COUNTY 0e %
Orcoke

/PAMLC SOUND

Hattero s ~ ~ ~ ~ ~ ~ ~ ~ ~~~~50Daa

Dune~~~~~~~~~Dt 94~9

(a)Due lnean hih atelne Compoiemaanulrtsf
chang (fe2e.6a) 94-91

SCALE: 1 inch= 8 miles

/ ~ *HYDE COUNTY
DARE COUNTY

PAMLICO OUND

|t/ eratteros

'/'

I IEosion

Figure 5. Hyde and southern Dare Counties

(b) Dune line and high water line. Mean annual rates of change
'n.2 t io n

ec .o ~crettonI

Figure 5. Hyde and southern Dare Counties
(b) Dune line and high water line. Mean annual rates of change
(feet per year) for most recent time interval, 1958-1971.

n0 SCALE: 1 inch = 8 miles O

HYDE COUNTY DARE COUNTY
ke~~~~~~~~~~~~~~Oe
~ Ocrocoke ; 11 ' "

/ �. ,~./ ,PAMLICO SOUIND

| |` t XOttro

I 1 o'7X;5-_ \~~~~~~~I
Inc,, d. \tterci
%~~~

)9Jp, $: , 4 "~~~~~~95 64 3 .
1'961 26.4 L 96

previous time i t v l
1953- 11.8 la"'

;II. 5 1962 -6.4~~~196

7.$

'955 195
1~~~~~~~~~~~~~~~~~~955 c
Eroxi 19; 6.~~~~~~~~~~~~~~~~Eo
7 ..3
1953 \955
Z 14.4~~~~~~~~~~~~~~~ 1955

previous time interval~~~_ s.o
11~~~~.8
ACccretlen ~
4955 �

Figure 5. �Hyde and southern Dare Counties
(c} Dune line. Mean annual rates of change (feet per year) for
previous time intervals.

SCALE: I inch 8miles

s% HYDE COUNTYDAECUT

PAMLICO SOUND

H~~~~~~~~~~~~~~~~~~~~~~~~~~~~actteras

1962~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-
Fiue54yeadsuhr aeCute
(d) High waEroln.Ma nulrtso hne(ee e er
936 ~ ~ ~ ~ frpeiostm itras

DARE COUNTY SCALE: Iinch 8 miles

I~~~~~~~~~~~~~~~~~~I~

5. . ,

Erosion
Dune 7=1 3. 4 -32 -5.-5. 3 .7 -1.9 -1.0+

- - ~~~~~~~~~~~~~~~~~Accretion

Erosion
High M 2 0 -. 2 3 -. 28-0.1I
Water ______
Line 6.5 0.5 ~~~~~~~~~~~~~~~~~~~~~~~0. 7

1949 -1971 Data... 1952 - 1971 Data D- Aceto

Figure 6. Northern Dare and Currituck Counties
(a) Dune line and high water line. Composite mean annual rates of
change (feet per year), 1949-1971.

DARE COuNTy CRITC CUT SCALE: 1inch 8 miles

91. ~ ~ ~ ~ ~~~.0 C1

0' 1 .4/

Erosion

High -2.3 -0.1 -30 -3.2 -2.9 -7.1-1.
Water
L ine 4.7 2.3
Accertion

195B ~~~~~1955-1971 Data .1961-1971 Data
1971-
Data

Figure 6. Northern Dare and Currituck Counties
(b) Dune line and high water line. Mean annual rates of change
(feet per year) for most recent time interval, 1955-1971.

SCALE: 1 inch : 8 miles
DARE COUNTY CURTUCK COUNTY

teo CURRITUCK COUND Isynd

RI N IA
E 8

Incre-
moent
mrent - E rosion
1961 --
1965
16.0 29.5 21.7
1955 -
1961
1958- 0.1 0.1
1962 316 1958 - Erosion
-1961 10.9 5.6
1.6
Accretion
1955-
1962
10.5 5.8 7.4
1955- -13.2 1955- Erosion
1958 1958 0 9
6.8 10.4 Accretion

1952 - Erosion
-2.3 -5.0 - 7.7

2.7 2.7
52.7 2.7 _Accretion
1949- -5.9
1955
1.7 _

Figure 6. Northern Dare and Currituck Counties
(c) Dune line. Mean annual rates of change (feet per year) for
previous time intervals.

SCALE: 1Inc ie
DARE COUNTY CRIUKCUT

ant Island~~~~~~on

ic~~~~~~~~~~~~~~~~~~~~~~nre - 95 .

Acretion
1955-~~~11 -. 217- 25

1959o - 19615

1962 --E

1955- ~~~~~~~~~~~~~~~~~~~~~~13.6 1.8
1962
-~~~. 3.3 8.1

1955 - Erosion

6.2 13.8 24.0 Acrto

1955 192--0614 -Eoso

1958 - -1955 - a__________
-~~~~~~~ ~~~~~~~162 -53 7 . 3.9 0.6 Accretion
1949 - 16 2 5. 5.7
1955

Figure 6. Northern Dare and Currituck Counties
(d) High water line. Mean annual rates of change (feet per year)
for previous time intervals.

PREVIOUS PUBLICATIONS PUBLISHED
By
THE CENTER FOR MARINE AND COASTAL STUDIES

Wave-Current Force Spectra, C. C. Tung and N. E. Huang, Report No. 72-2,
December, 1972

A Survey of North Carolina Beach Erosion by Air Photo Methods, H. E. Wahls
Report No. 73-1, May 1973

Sediment Movement in Tubbs Inlet, North Carolina, Robert P. Masterson, Jr.,
Jerry L. Machemehl and Victor V. Cavaroc, Jr., Report No. 73-2,
June, 1973

Influence of Current On Some Statistical Properties of Waves, C. C. Tuna
and N. E. Huang, Report No. 73-3, December, 1973

CTD Sensors, Specific Conductance and The Determination of Salinity,
C. E. Knowles, Report No. 73-3, August, 1973

Planning for North Carolina's Coastal Inlets - An Analysis of the Present
Process and Recommendations for the Future, William S. Tilley,
Report No. 73-4, September, 1973

A Preliminary Study of Storm-Induced Beach Erosion for North Carolina,
C. E. Knowles and Jay Langfelder and Richard McDonald, Report No. 73-5,
October, 1973

A Historical Review of Some of North Carolina's Coastal Inlets, Jay
Langfelder, Tom French, Richard McDonald and Richard Ledbetter,
Report No. 74-1, January, 1974

Statistical Properties of Kinematics and Dynamics of a Random Gravity
Wave Field, C. C. Tung, Report No. 74-2, June, 1974