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DEPARTMENT OF THE ARMY
CORPS OF ENGINEERS

THE

BULLETIN

OF THE

BEACH EROSION BOARD

OFFICE, CHIEF OF ENGINEERS
WASHINGTON, D.C.

VOL. 7. JULY 1, 1953 NO.3

TABLE OF CONTENTS
Page
Calculation of Refraction Factor Along a Wave Ray wesc... 1

Progress Reports on Research Sponsored by the Beach
Erosion Board CHSC OSSCTEHSSHSHHOSSHEHSHESHTHTHHSHOHHOSHSGOSOB ORBLE 2E 13

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DEPARTMENT OF THE ARMY
CORPS OF ENGINEERS
BEACH EROSION BOARD

0 0301 OO44%50b 2

OMAN

VOL. 7 1 July 1953 NO. 3

a,b = distances along y_-axis to adjacent contours
Cc

= wave velocities at adjacent contours
Tee = curvature of contour
A@ = angle included by tangents to contour
m = length of chord connecting points of tangency
8 = angle between integral curve and s-axis
K = curvature of integral curve
h = depth of water
L_ = wave length in deep water

curvature of wave crest

Kn

c, = wave velocity in deep water

A= parameter depending on p and q
Introduction

The refraction factor, K, which is a linear measure of the effect of
refraction on the height of water waves, has been calculated by measuring
the separation distance between two
neighboring rays (orthogonals) on
a refraction diagram. For later con-
venience define a ray separation
factor

iS WI oe

2 2 a Bas
where Y, designates the distance contour ~
between the given ray and an ad-
jacent ray at some initial depth,
and y the distance between the rays
at an arbitrary depth (Fig. 1).
The refraction factor is then,

cae. ne

depending on whether the arbitrary

depth is outside or at the Fig. |
depth of breaking. (Munk and

Traylor, 19:7).

woe

Values of B or K determined from measured values of y, and Y do
not apply to a point on either ray but to som point between the two rays.
Where rays diverge greatly over underwater canyons, it is not always
possible to construct rays close enough together in deep water to avoid
uncertainty in the value of K in shallow water. On the other hand, two
rays may approach so closely over an underwater ridge that minor inaccuracies
in ray position will introduce gross errors in the measured separation
distance Y .

The difficulties are avoided if the adjacent ray is imagined to be as
close as desired to the given ray, i.e., if B is regarded as the ratio
between two infinitesimal distances y andy, . With this interpretation
it is no longer possible or necessary to construct the adjacent ray and to
measure y and Yo « The two rays will still diverge or converge according
to the drientation, spacing and curvature of the depth contours in a
manner similar to rays which are separated by a finite distance. The de-
pendence of 8 on the ray path and contours has been evolved.

The present paper illustrates a method for calculating B, and there-
fore K, in terms of distance s measured along the ray and its infinitesimally
close neighbor. The basic relationship is a second order differential
equation. The coefficients of the equation must be computed from the
spacing, orientation, and curvature of the contours traversed by the ray.

The problem, then is to calculate the value of B as a function of s along
the ray from the differential equation by use of a graphical or numerical
method.

Results from Theory

It is assumed that the wave
velocity, c, is known from the depth
contours and that a ray has been con-
structed by the crestless method contours ~—=—__>. Ye
(Johnson, O'Brien, and Isaacs, 19)8;
Saville and Kaplan, 1952; Arthur,
Munk and Isaacs, 1952). Let s denote
the arc length along the ray. and a
the angle between the ray and the
x-axis (Fig. 2). By proceeding
from basic principles of refraction,
it may be shown (Munk and Arthur,
1952) that B = B(s) is a solution
of the ordinary second order
differential equation

Fig. 2

2
Seepiclicgs 00) °°O;
(1)

where

p(s) = -(cos aE =| - (sin 22 2| i one)
2 2 9
gl) = cinta 2 = |- 2(sin a cos off < =| + costal * ] :

and where the symbol D/\s denotes differentiation with respect to the arc
length s along the ray. In general, p and q are not known analytically, but
they can be computed at discrete points along the ray if the depth contours
are labelled in terms of wave velocity c. Equations (2a,b) ‘show that p

and q depend upon a and c and the first and second derivatives of c, i.e.,
upon the properties of the contours mentioned previously. After p and q

ave determined, an approximate solution for B along the ray may then be
obtained from (1) by a method due to Kelvin.

Determination of Coefficients p and q

Values of p and q at any point P on the ray in terms of a local co
ordinate system (x9) oriented with respect to the contour at P (Fig. 2)
are (Munk and Arthur, 1952)

: 1 oc

p(s) = -(sin a2 = |

c

(2c ,a)
2 2
E 2 aa, 3 Aine Vie 8 2 2S
a(s) = (cos a } 2(sin a! cos « IE ae (sin"a ee] ’

where Keis the curvature of the contour at point P. The curvature is
positive in sign when the contour is concave as viewed from the positive

end of the Y,7akiSe Thus, the curvature of the contour at point P is
positive in ~ Figure 2. If derivatives are computed from finite differences
and if it is assumed that contours in the vicinity of P have constant
curvature and centers of curvature on the Yoraxis » then the approximate
values ar

e€
Gy of
2 : aby ho) a
Deeg aeeee [2 |
b

c -c e=-c
E (3a,b)
qt (eos a!) - —~___4— + Kop sina’.
=

In (3a,b), the quantities a and b denote the distances along the y,~axis

aie

from point P to adjacent contours with wave velocities c_ and Ch» respective-
ly (see Fig. 2). :

If the contours are straight, the second term on the right-hand side
of (3b) is zero (Me¢ = 0) and if c varies linearly along y_,the first
term is zero. The curvature of the contour is approximated from a measure-
ment of the angle, AZ , included by two tangents to the contour (Fig. 3),
and of the length, m, of the chord connecting the points of tangency, since

K " cos SB
ce" m/2 (L.)

The derivation of (li) assumes that
the tangents include a section of
the contour of constant curvature.

contour. Kee ‘Caen

By application of (3a,b) and
(1), the values of p am q at
points of intersection of the ray
and successive contours are ob-
tained °

Solution for B ‘by Kelvin's Method

The integral curve B = B(s)
for (1) can be constructed in a 8B,
s-diagram, where the arc length,
S, measured along the ray is laid
out rectilinearly (Fig. li). The Fig. 5
basis of Kelvints method (Willers, 198) is the assumption that over small
intervals of s the integral curve § = B(s) has constant curvature. If
the angle between the integral curve and the s-axis is 9 , then the slope
of the curve is D@/s = tan 9 , and the curvature, using (1),.is

2 2
K Ztues = - (p tan ® +48) cos*e . (5)

ie fa + opps) :

_ The construction is begun at a point on the ray where B and DBs are
known. Usually this is a point in deep water, say where the ratio of depth
h to deep water wave length Ly is h/L_ = 0.5. Along the ray to this point
the effects of refraction are usually negligible, so that 8B = 1 and dB/Ds = 0.
The construction may be started at any point, however, if the value of B
and the curvature, » of the wave crest are known since

a pe Kk. (6)

It is convenient to take s = O at the initial point. The values of
coefficients p and q are computed at the initial point by the method of the
previous section using (3a,b). The value of (K,)_ at the initial point

ie)
foe

|

|

|

|

/ s!

/ al

+2 a

ay S|

/ =|

i CoN
LP

pmo

[-.} ee =|

Lp ae |

Negi ee

Fig. 4

is then computed from (5), and an arc of radius 1/(K,) is draw from
point s = 0, B = 1 on the B , s-diagram. The center of -curvature lies

on a line perpendicular to the known tangent direction, tan ok =Dp/s = 0,
i.€., on the B-axis.

The distance s = s, along the ray to the next contour is obtained,
approximately, by measubing the length of the chord or tangents drawn in
the ray construction, The circular arc in the B, s-diagram is extended to
S = s,, and the value B = B, is read. The angle 9 = 8, is obtained from
the direction of the tangent at s = Sy> Ba By» and then (Ka )3 is computed
from (5) introducing By» 955 and the values of p and q mS ey to the
point s = sj on the ray. A second are of radius 1/(K 4 is smoothly

joined to the first by taking the center of curvature on a line perpendicular
to the tangent at s = Sy: () 5 Bie The arc is extended to s = Sos the

distance along the ray to the next contour intersection, and the process
is repeated. The integral curve B = B(s) for (1) is thus approximated.

The application of Kelvin's method in solving (1) parallels the use
of the method as a basis for the direct construction of the ray (Arthur,
Munk, and Isaacs, 1952), As in ray construction, the radii of curvature
may be large, and it is more suitable to simply construct the chord or
equal tangents to the circular arc as shown to the right in Fig. . The
angular change A9 , which is required for the construction, is calculated
from

sin(Q + AQ) = Kgs +sin® , (7)

a relationship which follows from the geometry of the figure.

For example, knowing % and (Ke)y ats = s, in Fig. , the angular

change AG, for the interval As, = Sp ~ Sy is calculable from (7) written

1
in the form

fh par anelt ;
Ae, = sin [ Ka) - As, + sin 2, - 0, -

The chord or equal tangents are constructed from Sys By and their inter-
section with the line s = 55 gives B = Boe The integral curve

at Sos Bo makes an angle 8, = 8, + AG, with the direction of the s-axis.

If desired, the graphical construction can be avoided and the change
AB calculated from

AB = As . tan (9 + 32) (8)

Equations (7) and (8) are employed in the example which follows.

-7-

Example: An analytic example has been selected in order that the
approximate method of solution for B outlined above may be compared to an
exact solution. Assume an underwater trough with straight axis (Fig. 5,.
lower) along which

2
p= 0.1/1.3 q = -0.1/L, 5 (9a,b)

where L is the deep water wave length. The straight axis is obviously

a ray, along which 8 = B(s) may be determined, Actwily, the dimension-
less distance s/L_ is used. From (9a,b) and (2c,d), it may be shown

that along the axial ray

c/c, = e70e1s/Lo ; Ke = a1) (10a,b)

where c_ is the deep water wave velocity. The contours (dashed lines in
IAG 5)? have been drawn by extending tangents from the ends of circular
arcs each of radius L_ and each subtending an angle of 60°, Values of
e/e, and corresvonding values of relative depth h/L, are indicated.

Successive values of A8 and AB have been calculated along the axial
ray using Kelvin's method as a basis. Values of the variables are shown
in Table 1. The resulting points B,s/L_ have been plotted (Fig. 5, upper),
and a smooth curve drawn through them. The constant values of p and q
given in (9a,b) have been used in the computation. However, determina-
tions of p and q have also been made using (3a,b) and (1), and the values
were within a few percent of the exact values (9a,b).

For comparison, a second ray has been constructed by the crestless
method as close to the axial ray as the scale of the enlargement (L_ = 1
inch) permitted. The second ray has not been drawn beyond the poin
where the contours become straight. The value of K computed from measure-
ments of the separation of the two rays at c/e_ = 1.0 and at c/e_ = 0.5 is
0.48, which is to be compared to the exact valte 0.51. ¢

The exact solution of (1) along the straight axial ray with constant
values (9a,b) of p and q is well known and, if the initial conditions
Bo= 1, Op/s), = 0 are used, takes the form (Munk ami Arthur, 1952)

B= oP S/2foosh (As) + a sinh (As) | ' (11)
2
where p/2 = 0,05/L, and X = (p/2)2 - q = 0.1025/1,.°. Exact values of K
for certain values of s are tabulated.
Discussion

The example indicates the accuracy which may be expected in the
determination of refraction factor, K , along a single ray by Kelvin's
method. The accuracy, of course, decreases over those sections of the ray
for which there is large change in curvature, K as of the curve B = B(s)

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from one interval to the next. Decreasing the interval, as was done in
the example for c/e <0.5, and slihegiaiorell horns contours, if necessary, will
improve the accuracy.

Since exact values of p and q from (9a,b) were used in the example,
there is no indication of the effect of inaccuracies introduced by (3a,b)
and (). Some indication of the effect of errors in p and q may be ob-
tained from (11). If, for c/c_ = 0.25, the values of p and q differ by
10 percent and 15 percent, respectively, from values (9a,b), the value
of K changes by less than 15 percent.

The calcul ation of refraction factor along a ray has an advantage
when the depth and wave velocity are expressed analytically, because any
ddsired degree of precision may be achieved. This is not the case if the
usual method of constructing an adjacent ray and measuring the separation
distance is utilized. As mentioned previously, the latter method permits
determination only of a sort of "average" value of K appropriate to the
interval between the rays. There is always a physical limitation to the
proximity at which an adjacent ray may be constructed. In Figure 5, it
does not seem useful to continue the adjacent ray farther, because it has
reached a region where the curvature and orientation of the contours is
entirely different from along the axial ray.

The calculation of K along a ray is more time consuming than the usual
method involving construction of an adjacent ray, For this reason, the
usual method would appear to be preferable for complex underwater topography
where the depth is not known analytically but only from bathymetric charts.
An exception occurs where rays converge or diverge rapidly as over under-
water ridges or troughs, for under these conditions values of K from the
usual method may differ greatly from precisé values which apply to a point
on aray. It should be mentioned that it is just these circumstances for
which the applicability ~ of ray theory and refraction factors is most
questionable. However, the present remarks have been concerned entirely
with the determination of refraction factors rather than their applicability.
Values of K are correctly calculated by the present method even in the
region of a caustic, but the breakdown of the approximations of ray theory
prevents valid determinations of wave height from refraction factors under
these circumstances.

REFERENCES

Arthur, Re Se; Munk, We H; and Isaacs, J. De, 1952, The direct construction
of wave rays, Trans. Amer. Geophys. Union, 33, 855-865.

Johnson, J» We; O'Brien, M. P; and Isaacs, J. D., 1948, Graphical con-

struction of wave refraction diagrams, HO. Pub. Noe 605, 15 pp.
Washington, De Ce

Munk, W. He; and Arthur R, S., 1952, Wave intensity along a refracted
ray, Gravity Waves, National Bureau of Standards Circular No. 521.

Munk, We He; and Traylor, Me Ae, 1917, Refraction of ocean waveS...e.e,
Je Geol, 55s 1-26.

Saville, T., Jr.; and Kaplan, K., 1952, A new method for the graphical
construction of wave refraction diagrams, Bull. Beach Erosion Board,
6, now 3, 23-3h.

Willers, Fr. Ae, 1948, Practical analysis, 22 pp; New York, Dover.

PROGRESS REPORTS ON RESEARCH SPONSORED BY
THE BEACH EROSION BOARD

Abstracts from progress reports on several research contracts in force
between universities or other institutions and the Beach Erosion Board,
together with brief statements as to the status of research projects being
prosecuted in the laboratory of the Beach Erosion Board, are presented as
follows:

To University of California, Contract No. DA-l9-055-eng-8
A, Status Report No. 8, 1 Feb through 31 Mar 1953

This report pertains to the origin of sand upon beaches, especially
with reference to the beaches of Southern California.

The primary object of the present phase of work on the contract is
to drill holes through the sand fill west of Santa Barbara breakwater to
procure undisturbed samples of the sand and of the offshore sediments
that were beneath the water just prior to the time the fill was deposited.
These studies are designed to provide information on the nature of the
sediments under different conditions of transport of sand in shallow
waters adjacent to the beach. Ordinarily core samples of such offshore
sediments would have to be obtained with the aid of a drilling barge, but
at Santa Barbara, where the offshore area was covered by fill following ‘the
construction of the breakwater, samples of ‘the offshore sand can be ob-
tained by drilling through the fill by an ordinary well drilling rig.

During the past two months a series of undisturbed core samples were
obtained from seven holes in the area of fill west of the breakwater.
The samples extend to more than 500 feet seaward from the original shore
line and for. approximately one-fourth mile along the beach parallel to
the shore. The holes ranged in depth from 20 to 30 feet and bottomed in
bed rock, of Pleistocene sand and clay on the east part of the fill and
Miocene shale on the west part. The samples were obtained by means of a
special underwater core sampler designed by Dames and Moore, ‘Consulting
Engineers, of San Francisco and Los Angeles. This device procures drive
samples 10 inches in length and 2 inches in diameter. The samples were
collected in thin wall brass cylinders and were sealed with paraffin to
conserve the original content of water. Samples were taken at intervals
of 2 to 3 feet. The laboratory study of the material is now in progress.

B. Status Report No. 9, 1 April through 31 May 1953

The 60 core samples of beach material from the filled area west of
the Santa Barbara breakwater collected during March are now in the process
of analysis. The cores have all been opened, photographed, and more than
200 samples removed for. mechanical analyses. The program of analysis is
about 50 percent complete. Preliminary microscopical examination of the
cores has also been made. One half of each core has been saved for
supplemental work which may be needed after the present series of studies:
has been completed.

age

Work contemplated during June and July. The mechanical analysis of
the samples will be completed, the results compiled statistically, and

other studies initiated upon the basis of the results obtained.

[eles Scripps Institution of Oceanography, Quarterly Progress Report
No. ie, January-March 1953.

Analyses of the total heavy mineral content of the sediments from
the March 1950 survey were completed this quarter. The areal distribution
pattern of heavy-minerals for the March survey is similar to that of the
August 1949 survey, but differs somewhat as to detail.

Experimental measurements of the effects of accelerative forces on
the orbital current meter have been applied to theoretical velocity dis-
tributions. The relatively small magnitude of accelerative terms in
these theoretical cases suggests that accelerative terms are also small
in the case of actual waves outside of the breaker zone. Generally speak-
ing, the form of the velocity distribution curves obtained in the field
shows good agreement with the theoretical distributions.

The program of underwater survey using a datum obtained by placing
reference rods on the bottom is being expanded. New and larger steel rods
are being used. A new method of locating the general area of the rods
from the surface has been developed.

On 5 March a survey showed that a considerable slide had occurred in
South Branch of Scripps Canyon, the first slide to have taken place in
this particular area since 25 December 1951. This interval is consider-
ably longer than previous intervals between slides. The maximum deepen-
ing was approximately 11 feet, near the head of the branch, where the
depth had been 16 feet. At about 120 feet farther down the axis
the depth increase had diminished to about 3 feet. Some change is also
indicated in the adjacent branch, and in one profile a small valley, about
3 feet deep, developed along with a general deepening of the area by
several feet, so that the shape of the profile is considerably altered.

A manuscript which presents the details of a sample calculation of
wave refraction along a single ray (orthogonal) has been prepared.

III. New York University Second aes Progress Report for
period 1 March to 31 May 1953.
Hindcast Data - Checks of a wave spectrum forecasting method as de-
veloped from the theoretical spectra derived by Prof. Neumann are being

made against situations in which they can be checked off by observations
prior to preparing the statistical hindcasts.

Three years of 6 hourly weather maps have been assembled and work
will begin soon on the actual task of preparing the hindcasts.

“Lhe

Wave Analyzer - After trips to NRL and NACA to view current
spectral analyzers, two papers were submitted to the Board for review.
The first paper discussed the design of the optimum filters. The second
paper discussed the overall design of the analyzer which is based on a
heterodyne principle which will eliminate many of the difficulties of
current analyzer désigns.

Conferences with the Board staff cleared up some of the features of
the analyzer and plans were made to proceed with its construction. The
component parts have been ordered, and work has begun.

IV. The Agricultural and Mechanical College of Texas, Quarterl
Report for Period ending 31 March 1953.
The progress made during the first three quarters of this contract

period has been summarized in the Quarterly Report for the period ending
December 31, 1952 and dated January 15, 1953.

During this quarter of the contract period, the following progress
was made.

1. Field Operations. No additional wave data was obtained during
the fourth quarter. This was due to a temporary abandonment of the
Pure Oil site and the facilities available there. During the last week
of January, when the driller was bringing in a fifth well on the Pure
Oil Structure A in Block 32, a fire broke out and completely destroyed
the drilling platform. All Research Foundation instruments had to be
removed from the instrument shack located on the Quarters platform.
This included two of the wave recorders and pressure heads furnished
the Research Foundation by the Beach Erosion Board. One of the units was
installed permanently at this site. The other set was housed temporarily
in the instrument shack, awaiting for a suitable time and opportunity to
install at Pure Oil B Structure located 14,500 feet SW of A Structure.

In the process of moving the instruments from the instrument shack
only minor damage resulted, most of which has already been repaired.
In addition 75 feet of two conductor cable and a case for one recorder
became lost or misplaced in the shuffle. It is hoped, however, that the
above items may still be recovered.

2. Wave Data. The analysis of the wave records taken last summer
has been completed. Of the data, only ten runs had waves of large
enough magnitude to analyze reliably. The friction factors associated
with the above runs have been calculated and vary between .032 to .15,
with a mean at .070 and median at .06l:.

Very little data has been accumulated on the generation of shallow
water wind waves during the winter months. This, of course, is due to
the temporary, forced abandonment of the Pure Oil Site.

3. Theoretical Investigation. A theoretical investigation on the
"Change in Wave Height Due to Bottom Friction, Percolation, and Refraction"

=-15-

has been completed. This work was partly sponsored by the Office of Naval
Research, U.S.N., and was performed jointly by G. L. Bretschneider and _.
R. O. Reid.

The dissipation functions for bottom friction and percolation given
by PUTNAM and JOHNSON, and PUTNAM’. , respectively, have been used in
the development of a general solution to the problem for (a) a bottom of
constant slope and (b) a bottom of constant depth. Special solution of
the general equations are also developed, from which it is possible to
calculate the actual wave height as a result of a number of different com-
binations of bottom friction, percolation and refraction. A set of
nomographs have been prepared and can readily be used to determine the
energy loss of waves.

The method developed is an improvement on the method prepared by
PUTNAM, in that it avoids computations by successive approximations.
Consequently, the work involved in determining the energy loss of waves
is greatly reduced. Furthermore, it is possible to calculate directly
the friction factor from wave records at two stations along the path

' of wave travel.

h. Annual Technical Report. An annual technical report on wave
energy loss is practically completed and will be forthcoming before
1 May 1953. The technical report consists of two parts, one on the
theoretical work and one on the field work of the past twelve months.

Ve Massachusetts Institute of Technology ,Progress Report for
Period 1 December 1952- 20 February 1953.
Tn the following is given the first progress report of the project as
of March 1, covering the period December 1 through February 28, which from
now on will be followed by others at regular intervals. (As of June l,

1953 the equipment assembly was nearing completion and tests were expected
to be under way during the summer).

A. Experimental Equipment
1. Wave Channel: The channel is part of the permanent equipment of

the Hydrodynamics Laboratory. It is 30" wide, 36" deep and has a working
section of 90 feet. A large steel entrance or exit tank and transition

is provided at each end. The walls of the channel are of 1/2" plate glass
over the whole 90 feet. The bottom is horizontal and is of 1/2" plate
glass for hO feet and of 1/l\" steel plate for 10 feet and 40 feet at

the upstream and downstream ends respectively. Construction of this flume
has been proceeding for the past year and is now rapidly nearing com-
pletion.

2. Wave Generator: The generator proper consists of a horizontal
aluminum piston with a vertical face, suspended from a rail-mounted
carriage on top of the entrance tank. The carriage-piston is actuated by
a cam-operated, hydraulic servomechanism and has continuously variable
amplitude and frequency. When completed this generator will be, to our
knowledge, the second wave generator in the United States, the amplitude

-16-

and frequency of which are continuously variable while the machine is
in operation. This is an important feature when stopping a particular
movable bed test.

3. Range of Operation: A maximum value chart was plotted for shallow
water waves assuming sinusoidal profiles and indicates, for instance, the
rmge of values of wave length obtainable for a given amplitude and depth
within the limits of the flume geometry and the power of the generator.

4. Baffles: Plans are presently being drawn for lightweight aluminum
frames to hold 6" mattresses of cinders to be used as baffles. As many
of these mattresses as necessary will be lowered into the entrance tank
behind the generator to absorb the energy of the waves generated by the
back of the wavemaking piston.

5. Experimental Beach: Plans are at present being drawn for
a hinged, adjustable slope false bottom which will support the beach
material. The beach will be located on the 40 foot steel bottom section
of the flume.

6. Instrumentation

ae Instrument Carriage: Complete plans have been drawn for a
general purpose instrument carriage which will ride the length of the
flume on rails and will provide for more convenient mounting of any one
of the following instruments:

Point gage

Prandtl Pitot, Tube

The capacitance type turbulence gage developed at the
Hydrodynamic Laboratory

Construction of the all purpose carriage will probably not
be undertaken until June 1953, since it will not be needed
in the preliminary test program.

b. Photographic Equipment: It is planned to record the wave
profiles and the history of their transformation by photographing through
lucite grids on the wall of the channel. Three of those grids-will be
required. The motion of sediment and internal wave particles may also be
recorded in this manner.

To perform this job, the laboratory is equipped with the following
standard items:

One 16 mm. movie camera with a range of 8 to 6 exposures
per second.

One }"" x 5" Graphic View Camera as well as one 35 mm. camera.

Lighting equipment consisting of one Strobotac with a range
of 600 to 14,400 flashes per minute, six Strobe-Flash lamps
with power packs and two photo flood lamps.

One electric timer graduated in thousandths of a second.

-l7-

B. Proposed Range of Experimental Variables

1. Wave length: 1 ft. to 25 or 30 feet.

2. Amplitude =: O to 1’.

3. Period : 1 sec to 6 sec.

lh. Types of waves generated: Most of the waves will approach
the beach as Stokian or Cnoidal waves, since the flume size
limits the minimum practical value of ~A/y obtainable to
1/2. Deep water waves can be generated, but in an extreme-
ly limited range of wave lengths and depths.

5. Beach slopes: Slopes corresponding to those most frequently
found on the shores of North America have been chosen;
1 on 8 to 1 on 30.

6. Roughness: Smd.sizes have been selected to correspond with
the mean sand diameter found on the above range of North
American beaches. Range of mean sand diameter = 0.15 mm to 0. nm.

7. Movable particles: It is planned to use spherical glass
beads supplied by the Beach Erosion Board, in Grades No.
through 13 inclusive, corresponding to the roughness range
given in No. 6 above.

C. Plan of Study

1. Preliminary Study; on-shore, off-shore transport:

ae Initially a beach of uniform slope covered with fixed
gand grains of uniform size will be used to produce a definable roughness.
A section along the center of the slope will be covered with movable particles
of the same size as the fixed sand grains and a series of tests will be run
where each of the variables, depth, amplitude, wave length and slope will
be varied in tum. This will be done for both the smallest and largest
roughness and particles size listed above and will serve a three-fold
purpose:

Clearer definition of the pertinent range of the variables.

Provision of initial quantitative information as to the effect
of each wave characteristic on the motion of these two sizes.
This will provide an understanding of the mechanics of the
transport and a more intelligent approach to the problem of
selective sorting.

Perfection of experimental procedure including calibration of
the wave machine.

b. This part of the program may be extended to include the
complete range of particle sizes, a stabilized realistic beach profile
with sand ripples and internal velocity and turbulence studies if it ap-
pears advisabie at the time.

-18-

2. Study of Selective Sorting:

a. The slope will be divided into sections down the center
of the flume, each section containing a large sample of particles of a
uniform size. The selective sorting will than be studied statistically
and an attempt made to discover the functional relationship between the
variables considered with respect to sorting.

VI. Waterways Experiment Station Vicksbur Mississippi, Progress
Report for fe ending 31 May 1953.

Wave Run-up on Shore Structures - Overtopping tests and run-up on
a structure similar to the Galveston seawall, using a beach slope of 1 on

10 and 1 on 25 and a water depth of 29.5 feet involving seawall crest
elevations of +3, + 6, +9, +12, +15, +18, and +21 were completed. These
tests show that the run-up is higher on,and more water overtops, ‘the
eurved-faced wall than the vertical wall tested previously for the same
wave conditions. Overtopping and run-up tests on a smooth-faced pavement
with a seaside slope of 1 on 14 using crown elevations of +3,+6,+9,+12,
+15,+18,+21 and +2), a water depth of 29.5 feet and a beach slope of 1 on
10 were completed.

Effect of Inlets on Adjacent Beaches - Tests are being made in a
basin simulating an ocean and a lagoon, which are separated by a barrier

beach of sand that can be breached to reproduce the desired inlet. An
automatic tide control is used to reproduce tides in the ocean part of
the basin, which is also equipped with a 60-ft-long wave machine, and a
circulating system to reproduce littoral currents when desired. The
barrier beach is first stabilized by operating through a fixed cycle af
tides, waves, etc; the desired inlet is then cut through the beach, and
the same cycle of operation is repeated until the beach is again stabilized
with the inlet in place. Special attention is paid to the physical and
hydraulic characteristics of the inlet and the condition of the adjacent
beaches. Under the first several conditions tested the inlet closed
completely after a very few tidal cycles. The lagoon tidal apparatus
has been adjusted so that the inlet will be kept open, and a further
test is being undertaken.

VII. Beach Erosion Board, Research Division, Project Status Report
for Quarter Ending 15 Sane 1953.

In addition to the research projects under contract to various
institutions which are reported on above, the Research Division of the
Beach Erosion Board is carrying out certain projects with its own
facilities. The main unclassified projects were described in Vol. 6,
No. 4 of the Bulletin (October 1952) and a short description of some
of the work accomplished through the last quarter is given below.

=10=

Statistical Wave Data on The Great Lakes - Reports on the Lake
Michigan and Lake Ontario data have gone to press and will be distributed
in July as Technical Memorandums No. 36 and 37. The hake Erie report
has been completed and will go to press as Technical “lemorandum No. 38 in
July.

Project ESMOND - This is a new project being carried on by the
Nprth Atlantic Division for the Office, Chief of Engineers. The task
assigned to the Beach Erosion Board on this study is to determine by
laboratory testing, a relationship between some of the physical properties
(density and viscosity) of bottom fluff material and soundings obtained
therein with various shaped sounding leads. A preliminary testing of
various leads has been made in clear water for calibration purposes. A
h-foot diameter sediment tank, 10 feet high has been constructed with
glass side panels for use with fluff material obtained from the Delaware
River. The viscosities of the various water-fluff mixtures to be tested
are determined by use of a Brookfield viscometer, and the density by
standard measurements. Relatively undisturbed ~ samples of the fluff
under test will be taken at various depths in the sediment tank by use
of corporation cocks adapted to cylindrical tubes.

Wave Forecasting Methods - A comparison of waves forecast from a
single storm in the Pacific by both the Sverdrup-Munk and the Darbyshire
methods with those recorded by the University of California wave recorder
at Pt. Arguello is being completed. Preliminary examination shows, for
this one case, both methods to compare with the record with about the
same order of error except for about 16 hour time lag obtained with the
Darbyshire method.

Routine progress and analysis has been made on the other projects
being carried out by the Research Division, and a three week course
in wave phenomena and design techniques was given to certain District and
Division personnel. Project reports on the Accuracy of Hydrographic
Surveying and the Laboratory investigation of the Vertical Rise of
Solitary Waves on Impermeable Slopes, were published as Technical
Memorandums 32 and 33.

=20=

BEACH EROSION STUDIES

Beach erosion control studies of specific localities are usually
made by the Corps of Engineers in cooperation with appropriate agencies
of the various States by authority of Section 2 of the River and Harbor
Act approved 3 July 1930. By executive ruling the costs of these studies
are divided equally between the United States and the cooperating agencies.
Information concerning the initiation of a cooperative study may be obtained
from any District or Division Engineer of the Corps of Engineers. After
a report on a cooperative study has been transmitted to Congress, a summary
thereof is included in the next issue of this bulletin. A summary of re-
ports transmitted to Congress since the last issue of the Bulletin and
listsof completed ‘and. authorized cooperative studies follow:

SUMMARIES OF REPORTS TRANSMITTED TO CONGRESS

OHIO SHORE LINE OF LAKE ERIE - SHEFFIELD LAKE VILLAGE TO
ROCKY RIVER

The area studied is located in Loraine and Cuyahoga Counties on the south
shore of Lake Erie from about 7 to 22 miles west of Cleveland Harbor,
Ohio. It lies between Sheffield Lake Road in Sheffield Lake Village
and the mouth of Rocky River, a distance of about 15 miles. Lorain and
Cuyahoga Counties, including the city of Cleveland had a total population
of about 1,500,000 in 1950. The city of Rocky River and lake front
villages have a combined population of about 20,000. There is little seasonal
change in population of these areas. The property along the shore line
of the study area has been developed mainly for private residential
purposes. The shore is publicly owned at the Avon Lake Village Water-
works, at Huntington and Rocky River Parks and at a number of small
village parks. Narrow beaches existing at some of these parks are used
for recreational purposes.

The shore line of the study area consists of nearly vertical bluffs
from 20 to 60 feet in height. The surface stratum is composed generally
of boulder clay. The lower part of the bluffs exposed to wave action
is shale for most of the shore frontage of the area. There are few
beaches because of the small proportion of sand in the eroding bluffs and
because no material reaches the shore from - other sources. Miscellaneous
groins and walls have been constructed in an attempt to prevent erosion
of the shore. Groins have been ineffective due to scarcity of littoral
drift, except where the bluffs are composed of unconsolidated material.
West of Avon Point the predominant direction of the minor littoral drift
is westward, east of that point, except in the city of Rocky River, it is
eastward, as indicated by accretion at groins. In Rocky River a slightly
greater amount of material east of groins is indicative of a slight west-
ward predominance of drift.

The mean lake level for the months of March to December is about 1.6
feet above the established low water datum. The highest lake stage and
the highest monthly mean stage recorded at Cleveland, Ohio, are res-
pectively 5.25 and about ) feet, above low water datum. Storms cause

=2]-

changes in lake levels as winds move the water toward the ends of the
lake. Of winds which generate waves affecting the area, those from the
northeasterly quadrant have the greatest fetch, about 150 miles. Those
from the northwesterly quadrant apparently have an approximately equal
effect on material movement, as the predominant direction of drift is
eastward on the shore having a northwest-southeast orientation and west-
ward on shores having a northeast-southwest orientation. It is estimated
that, considering the effect of wind-set-up during easterly storms to be
about 1/2 foot, the lake could reach a level in the study area of about
h.5 feet above low water datum. During severe storms waves may range

up to 12.5 feet in height in deep water, but ordinarily waves of this
height would break before reaching the shore structure. The maximum
height of waves breaking landward of the low water datum shore line at a
design lake stage of 4.5 above low water datum would be about 3.5 feet.
Existing beaches have been preserved by groin systems. Any new beach
development would require artificial placement of fill and its retention
by a groin system. In those areas where no beach presently exists and
none is desired, the bluff may be protected by a seawall with top elevation
of 8 feet above low water datum and the slope above armored with stone
revetment to elevation 12 feet above low water datum. If the bluff above
the revetment is graded to a stable slope, so that slumping thereof would
not cause a horizontal thrust against the revetment, protection can also
be provided by a continuous belt of heavy riprap at the toe of the bluff
extending up to elevation 12 feet above low water datum. Ice forms a
protective coating over beaches during winter months, but the lifting

and battering actinn of shifting ice floes during the spring breakup must
be considered in designing shore structures for structural stability.

The division and district engineers and Beach Erosion Board have
developed plans for protecting and improving the shores of the study area.
They concluded that there is an insufficient natural supply of beach
material to provide beaches of the minimum width necessary to protect the
bluffs from erosion by wave action for the greater part of the study area
and that the most practicable general plan of protection of the shore
line consists of some type of seawall or revetment. They also concluded
that if additional beach is desired, the plan would consist of artificial
placement of fill and groins to retain the fill. They further concluded
that for the publicly owned shores, ho additional protection is required
cr that the protective benefits of the considered work are not sufficient
to make the project eligible for Federal participation under existing
laws. They recommended that owners of private property adopt the plan
of improvement considered best suited to local conditions and the desired
use of the property, and that continuous sections of shore be protected at
one time wherever possible to prevent flanking of isolated improved sections.
They recommended no Federal participation in the cost of any of the
proposed improvements.

In accordance with existing statutory requirements, the Board stated
its opinion thats

BDD=

a. It is not advisable for the United States to adopt a project
at this time authorizing Feddral participation in the cost of protecting
and improving the Lake Erie shore of Ohio within the area studied;

be No public interest is involved in the proposed improvements;
and

ce No share of the expense should be borne by the United States.

The Chief of Engineers concurred in the foregoing conclusions and
recommendations.

OCEAN CITY, NEW JERSEY

Ocean City is located on the coast of New Jersey about 35 miles
northeast of Cape May, the southern tip of the State at the entrance to
Delaware Bay. It comprises the entire length of the barrier beach island
8 miles long known as Peck Beach. Great Egg and Corsons Inlets are
respectively the northeastern and southwestern boundaries of the city
and island. The northeastern one-third of the island is the most develop-
ed portion. The total patronage of the resort is estimated at 500,000
annually. The summer residents are estimated at 75,000, compared to the
permanent population 5,950. Summer weekend vacationists are estimated
at 20,000. The assessed valuation of property in the city in 199 was
nearly $17,000,000. About 36 percent of the ocean beach is owned by the
city and the remainder is privately owned. Between Surf Road and 12th
Street the city owns 31.7 percent of the shore frontage.

The ocean tides at Ocean City are semi-diurnal, the mean range being
l feet and the spring range 5 feet. Tides exceeding 7 feet above mean
low water are rare. The maximum height of waves ebserved just offshore
was 8 feet. The direction of approach of waves close to shore is such
that littoral drift northeast of North Street is toward the inlet and
southwest of 5th Street is southwestward. The predominant direction of
drift in southern New Jersey is southerly, the apparent source of beach
material to the area being adjacent portions of the barrier beach to the
northeast. The rate of movement of material across Great Egg Inlet has
been irregular. Progressive improvements in the inlet region have re-
stricted the normal tendency of the inlet to migrate, resulting in a
change in the supply of material moving into the problem area. The
direction and intensity of wave action, as governed by bottom configuration,
and the paths of tidal currents, have become more restricted in zone of
shore influence due to limitations of former variability of channel
location. The deficiency in supply, averaging about 50,000 cubic yards
annually over the period from 1930 to 1950, resulted in recession of the
shore line so that the high water line at the time of the study, was
generally under or landward of the boardwalk as far south as 12th Street.
A groin system probably retarded the erosion to some extent, but the
beaches were unsatisfactory.

D3)

The district engineer developed a plan for protecting and improving
the shores, comprising restoration of the beach to a width of 300 feet
between the boardwalk or bulkhead and the high water line by artificial
deposit of sand, and stone extensions of 7 existing groins, and made an
economic analysis of proposed protective measures. He found that the
benefits from prevention of damages, increased earning power of land and
recreational benefits of the proposed work warrant the adoption of the
project of protection and improvement. He concluded that the public
interest therein warrants Federal participation to the extent of one-
third of the cost applicable to the publicly owned shore in accordance
with the policy established by Public Law 727, 79th Congress. The
division engineer concurred in the views and recommendations of the
district engineer.

The Beach Erosion Board concurred in the opinion of the reporting
officers that the prospective benefits warrant the expenditure for suit-
able protective and improvement measures. In accordance with existing
statutory requirements, the Board stated its opinion that:

ae itis advisable for the United States to adopt a project
authorizing Federal participation in the cost of protecting and improving
the shore of Ocean City, New Jersey;

b. The public interest involved in the proposed improvement is
substantial. 1t is associated with prevention of damages to public
property and recreational benefits to the general public; and

ce The share of the expense which should be borne by the United
States is one-third of the first cost of the work applicable to the
publicly owned shore. The estimated amount of this share is $199,000
(10.6 _percent of the first cost), based on present public ownership
of 31.7 percent of the shore frontage involved in the project.

The Beach Erosion Board recommended that a project be adopted by the
United States authorizing Federal participation, subject to certain con-
ditions, by the contribution of Federal funds in an amount equal to one-
third of the first costs of the measures for the protection and im-
provement of the publicly owned portions of the shores of Ocean City,

New Jersey, from Surf Road to 12th Street, under a plan for the entire
shore within those limits comprising artificial placement of suitable

sand fill in amount of approximately 1,900,000 cubic yards on the ocean
shore to widen the beach to a width of approximately 300 feet seaward of
the boardwalk or bulkhead to the mean high water line, and extension of

7 existing stone groins as deferred construction when experience indicates
the need thereof.

The Chief of Engineers concurred in the recommendations of the Beach
Erosion Board.

he

VIRGINIA BEACH, VIRGINIA

Virginia Beach is located on the east coast of Virginia about 19
miles east of Norfolk and 3.5 miles south of Cape Henry, which is the
south point of the entrance to Chesapeake Bay. The shore frontage of the
city is 3-1/3 miles long. The city is extensively developed as a resi-
dential and resort area. It has a permanent population of 5,300 and a
maximum summer population of about 5,000. A combined concrete promenade
and light seawall 1.93 miles long built in 1927 is owned by the city.

The shore frontage is owned principally by the city. The United States
owns a frontage of 205 feet, the site of a Coast Guard Station. The
remainder, less than 5 percent is privately owned.

The tides in the ocean at Virginia Beach are semi-diurnal, the mean
range being 3 feet and the spring range 3.6 feet. The maximum storm
tide of record was about 7 feet above mean high water, but tides greater
than 3 feet above mean high water are infrequent. Statistical data on
ocean swells off Virginia Beach indicate that the predominant direction
of high swells is from the northeast and east. Refraction effects of
the offshore bottom and effects of the tidal currents due to the proximity
of the entrance to Chesapeake Bay influence the wave pattern, so that the
littoral characteristics cannot be determined from existing data. There
is evidence of seasonal reversals in direction of drift, but no evidence
that there is a predominant drift of appreciable wolume in either direction.
The beach is composed of medium sand and the offshore bottom of fine sand.
The effect of major storms appears to be a temporary shifting of foreshore
material to the offshore area. The required protection to the seawall and
upland can be provided by a beach of sufficient height and width so that
it will not be entirely removed during one storm period. Shore line re-
cession during the 1927 and 1948 storms indicates that an artificially
placed beach of suitable material with a minimum berm width of 100 feet
at an elevation of 7 feet above mean low water would be satisfactory for
this purpose. Material is restored to the foreshore during the adjustment
period following such storms, but presumably part of the material is not
returned and consequently the shore line gradually recedes. The low rate
of loss indicates that a restored beach may be economically maintained by
artificial replenishment as needed. As available data are inadequate to
determine whether groins would effect lower annual costs, it is advisable
to include them in the plan of protection for deferred construction if
needed.

The district engineer developed a plan for protecting and improving
the shores, and made an economic analysis of proposed protective measures.
He found that the benefits from prevention of damages, increased earning
power of land and property, and recreational benefits of the proposed work
warrant the adoption of the project of protection and improvement. He con-
cluded that the public interest therein warrants Federal participation to
the maximum extent permissible under the policy established by Public
Law 727, 79th Congress.

Bis.

The division engineer concurred in the conclusions and recommendations
of the district engineer.

The Beach Erosion Board concurred in the opinion of the reporting
officers that the prospective benefits warrant the expenditure for suitable
protective and improvement measures, and the Board recognized the feasibility
of providing the protective beach, within the limitations imposed by the
general plan, either by direct placement along the entire frontage in one
operation, or by placement of material initially in the southern section
and subsequently at strategic locations, to be distributed by natural
processes.

In accordance with existing statutory requirements the Board stated
its opinion. thats

a. It is advisable for the United States to adopt a project
authorizing Federal participation in the cost of protecting and improving
the shore of Virginia Beach, Virginia;

b. The public interest involved in the proposed improvement is sub-
stantial. It is associated with prevention of damages to public property
and recreational benefits to the general public; and

c. The share of the expense which should be borne by the United
States is the portion of the cost applicable to protecting the Federally
owned frontage plus one-third of the first cost of measures for the
restoration and protection of the other publicly owned portions of the
shore of Virginia Beach. The estimated amount of this share is $377,000
for the fill and $298,000 additional for deferred groin construction.

The Board recommended that a project be adopted by the United States
authorizing Federal participation, subject to certain conditions, by the
contribution of Federal funds in an amount equal to the portion of the
cost applicable to protecting the Federally owned frontage plus one-third
of the first cost of the measures for the restoration and protection of
the other publicly owned portions of the shore of Virginia Beach, Virginia,
under a plan for the entire shore within the city limits eomprising artificial]
placement of suitable sand fill in amount of approximately 1,100,000
cubic yards on the ocean shore to widen the beach berm to a minimum width
of approximately 100 feet at elevation 7 feet above mean low water and con-
struction of a system of approximately 21 groins as deferred construction
when experience indicates the need thereof.

The Chief of Engineers concurred with the recommendations of the
Beach Erosion Board.

OHIO SHORE LINE OF LAKE ERIE = SANDUSKY BAY
The area studied comprises the easterly 2 miles of Townsend Township
located in Sandusky County on the south shore of the westerly part of
Sandusky Bay. It is located about 10 miles west of the city of Sandusky,

be

Ohio. Sandusky Bay is located on the south shore of Lake Erie about
midway between Toledo and Cleveland. Its entrance and eastern end have
been improved by the United States for navigation. Sandusky County had
a population of 3,152 in 1950. The city of Sandusky and Erie County
exclusive of that city had populations of 29060 and 23,102 respectively.
The property along the shore line of the study area is devoted mainly

to agriculture, but some summer homes have been built along the shore.
Inland areas are devoted principally to the agricultural uses. The shore
in the study area is all privately owned.

Sandusky Bay is a shallow body of water almost completely land
locked, and connected to Lake Erie at its eastern end. Sandusky River
drains into the bay at its western end. The shore line of the study area
consists of eroding bluffs of lacustrine clay, rising to a height of
about 8 feet above low water datum, with little or no beach fronting
the bluffs. It has been estimated that only about 1h percent of the
material in the upper 3 feet of the bluffs is coarser than silt. From
the toe of the bluff, beach and offshore bottom slopes are very flat,
as is also the adjacent topography at the top of the bluff. No protective
structures have been constructed in the study area, but a stone dike was
constructed in 198 to protect a low marshy area about one mile east of
the study area. Small quantities of accretion on the east sides of small
impermeable boat landings along the shore line in areas adjacent to the
study area indicate a tendency for the small quantity of material avail-
able to move westward.

The mean level of Lake Erie for the months of March to December
is about 1.6 feet above the established low water datum. The highest
lake stage and the highest monthly mean recorded at Cleveland, Ohio, are
respectively 5.25 and about ) feet above low water datum. The average
water levels of Sandusky Bay and Lake Erie are approximately the same
over a period of time, but for Lake level changes of short duration the
bay level fails to reach the extreme of the lake level due to its narrow
entrance. During severe northeasterly storms, the bay could infrequently
reach a level in the study area of about 5 feet above low water datum.
Due to the shallow depth of the bay under normal conditions, waves seldom
exceed 23 feet. The maximum wave height that need be considered in design-
ing structures where no protective beach exists is probably 2 feet. At
low lake levels the flat slope of the bay bottom and the foreshore pro-=
tect the bluffs from erosion by wave action, but with higher levels of
water in the bay, waves reach and break directly against the bluff. Most
of the material eroded from the bluffs, due to its fineness, is apparently
deposited offshore by wave action. Consequently, little beach building
material is available for transport by littoral forces. Erosion of the
bluffs can be arrésted by sloping the bluffs and armoring them with wave
resistant material.

The district and division engineers, and the Beach Erosion Board
concluded that the most practical and economical method of protecting the
shores of Sandusky Bay within the study area is by grading the existing
vertical bluff and placing quarry-run stone on a filter blanket of crushed

Soe

stone from the toe of the bluff to its top at elevation 8 feet above low
water datum, and that no public interest is involved in the considered

plan of improvement, since there is no publicly owned property within the area
studied. They recommended that protective measures which may be undertaken
from time to time by local interests, based on their own determination of
economic justification be accomplished in accordance with the plan for
stone revetment proposed in the report. They further recommended that con-
tinuous sections of shore be protected at one time, where possible, to

take advantage of the saving in construction costs, as well as to prevent
flanking of the protective works where adjacent unprotected frontage would
continue to erode.

In accordance with existing statutory requirerents, the Board stated
its opinion that:

a. It is not advisable for the United States to adopt a project
authorizing Federal participation in the cost of protecting and improving
the shore of Ohio within the area studied;

b. No public interest is involved in the proposed improvements;
and

ce No share of the expense should be borne by the United States.

The Chief of Engineers concurred in the foregoing conclusions ad
recommendations.

LOR

LOCATION

Old Orchard Beach

COMPLETED COOPERATIVE BEACH EROSION STUDIES

COMPLETED
MAINE
20 Sep 35

NEW HAMPSHIRE

Hampton Beach 15 Jul 32
MASSACHUSETTS
South Shore of Cape Cod (Pt.

Gammon to Chatham) 26 Aug 1
Salisbury Beach 26 Aug 41
Winthrop Beach 12 Sep 7
Lynn-Nahant Beach 20 Jan 50
Revere Beach 12 Jan 50
Nantasket Beach 12 Jan 50
Quincy Shore 2 May 50
Plum Island 18 Nov 52

RHODE ISLAND

South Shore

(Towns of Narragansett, South

Kingstown, Charlestown &

Westerly) h Dec 8

CONNECTICUT
Compo Beach, Westport 18 Apr 35
Hawk's Nest Beach, Old Lyme 21 Jun 39
Ash Creek to Saugatuck River 29 Apr 9
Hammonasset’ River to East River 29 Apr h9
New Haven Hbr. to Housatonic Re 29 Jun 51
Conn. River to Hammonasset R. 28 Dec 51
Pawcatuck River to Thames River 31 Mar 52
Niantic Bay to Conn. River 1 Jul 52
Housatonic R. to Ash Greek 12 Mar 53
NEW YORK

Jacob Riis Park, Long Island 16 Dec 35
Orchard Beach, Pelham Bay,Bronx 30 Aug 37
Niagara County 27 Jun 2
South Shore of Long Island 6 Aug h6

BOs

PUBLISHED IN
HOUSE DOC. CONGRESS
76h, 80
134 82
167 82
145 82
90 81
239 7h
hou 81
7h 81
ban 82
31 83
oy 83
397 7h
S50 75
Daal 78

NEW JERSEY

Manasquan Inlet & Adjacent

Beaches 15 May 36 ale 75
Atlantic City 11 Jul hg 538 81
Ocean City 15 Apr 52

VIRGINIA
Willoughby Spit, Norfolk 20 Nov 37 482 75
Colonial Beach, Potomac River 2h Jan 9 333 81
Virginia Beach 25 Jun 52

NORTH CAROLINA

Fort Fisher 10 Nov 31 20k 72
Wrightsville Beach 2 Jan 34 218 73
Kitty Hawk, Nags Head & Oregon

Inlet 1 Mar 35 5 an
State of North Carolina 22 May 7 763 80

SOUTH CAROLINA

Folly Beach 31 Jan 35 156 7h
Pawleys Is., Edisto Beach 2 Jul 51
and Hunting Island.
GEORGIA
St. Simon Island 18 Mar 0 820 76
FLORIDA
Blind Pass (Boca Ciega) 1 Feb 37 187 75
Miami Beach 1 Feb 37 169 75
Hollywood Beach 28 Apr 37 253 75
Daytona Beach 15 Mar 38 571 15
Bakers Haulover Inlet 21 May 5 527 19
Anna Maria & Longboat Keys 12 Feb 47 760 80
Jupiter Island 13 Feb 7 765 80
Palm Beach (1) 13 Feb 7 772 80
Pinellas County 22 Apr 53

(1) A cooperative study of experimental steel sheet pile groins was also
made, under which methods of improvement were recommended in an
interim report dated 19 Sep 190. Final report on experimental
groins was published in 198 as Technical Memo. Noe 10 of the Beach
Erosion Board.

-30-

MISSISSIPPI

Hancock County 3 Apr 2
Harrison County - Initial 15 Mar hh
Harrison County - Supplement 16 Feb 8
LOUISIANA
Grand Isle 28 Jul 36
TEXAS
Galveston (Gulf Shore) 10 May 34
Galveston Bay, Harris County 31 Jul 3h
Galveston (Gulf Shore) 5 Feb 53
Galveston (Bay Shore) 23 Jun 53
CALIFORNIA
Santa Barbara - Initial 15 Jan 38
Supplement 18 Feb 2
Final 22 May h7
Ballona Creek & San Gabrie].

River (Partial) 11 May 38
Orange County 10 Jan 0
Coronado Beach h Apr 1
Long Beach 3 Apr 2
Mission Beach 4 Nov 2
Pt. Mugu to San Pedro BW 27 Jun 51
Carpinteria to Pt. Mugu h Oct 51

PENNSYLVANIA

Presque Isle Peninsula, Erie

(Interim) 3 Apr 2

(Final) 23 Apr 52

OHIO

Erie County - Vicinity of Huron 26 Aug 1
Michigan Line to Marblehead 30 Oct hh
Cities of Cleveland & Lakewood 22 Mar 8
Chagrin River to Fairport 22 Nov 9
Vermilion to Sheffield Lake

Village 24 Jul 50
Fairport to Ashtabula 1 Aug 51
Ashtabula to Penna. State Line 1 Aug 51
Sandusky to Vermilion 7 Jul 52
Sandusky Bay 31 Oct 52
Sheffield Lake Village to

Rocky River 31 Oct 52
Euclid to Chagrin River 18 Jun 53

Sale

682

92

00
7h

552
761

637
636

29

220
aid
502
596

351
350
32

80

75

13
7

15
80

76
17

83

ILLINOIS

State of Illinois 8 Jun 50
WISCONSIN

Milwaukee County 21 May 5

Racine County 5 Mar 52
PUERTO RICO

Punta Las Marias, San Juan 5 Aug 7

HAWAII
Waikiki Beach 5 Aug 52

asp

28

526
88

769

83

19
83

80

AUTHORIZED COOPERATIVE BEACH EROSION STUDIES
NEW HAMPSHIRE

HAMPTON BEACH. Cooperating Agency: New Hampshire Shore and Beach
Preservation and Development Commission

Problem: To determine the best method of preventing further
erosion and stabilizing and restoring the beaches, also
to determine the extent of Federal aid in any proposed
plans of protection and improvement.

MASSACHUSETTS

PEMBERTON POINT TO GURNET POINT. Cooperating Agency: Department of
Public Works.

Problem: To determine the best methods of shore protection,
prevention of further erosion and improvement of beaches,
and specifically to develop plans for protection of
Crescent Beach, the Glades, North Scituate Beach and
Brant Rock.

CONNECTICUT

STATE OF CONNECTICUT. Cooperating Agency: State of Connecticut (Acting
through the Flood Control and Water Policy Commission)

Problem® To determine the most suitable methods of stabilizing
and improving the shore line. Sections of the coast are
being studied in order of priority as requested by the
cooperating agency until the entire coast has been
included.

NEW YORK

N.Y. STATE PARKS ON LAKE ONTARIO. Cooperating Agency: Department of
Conservation, Division of Parks.

Problem: To determine the best method of providing and maintaining
certain beaches and preventing further erosion of the
shores at Selkirk Shores, Fair Haven Beach and Hamlin
Beach State Parks, and the Braddock Bay area owned by
the State of New York.

NEW JERSEY
STATE OF NEW JERSEY: Cooperating Agency: Department of Conservation and

Economic Development.

-33-

Problem: To determine the best method of preventing further
erosion and stabilizing and restoring the beaches, to
recommend remedial measures, and to formulate a com-
prehensive plan for beach preservation or coastal pro-
tection.

NORTH CAROLINA
CAROLINA BEACH. Cooperating Agency: Town of Carolina Beach

Problem: To determine the best method of preventing erosion of
the beach.

ALABAMA

PERDIDO PASS AND ALABAMA POINT. Cooperating Agency: Alabama State
Highway Department.

Problem: To determine the best method of preventing further
erosion of Alabama Point, for stabilizing the inlet,
and for determining the extent of Federal aid, if any,
in the cost of such proposed plans for protection and
improvement as may be recommended.

CALIFORNIA

STATE OF CALIFORNIA. Cooperating Agency: Division of Beaches and Parks,
State of California.

Problem: To conduct a study of the problems of beach erosion and
shore protection along the entire coast of California.
The current study covers the Santa Cruz area.

WISCONSIN
KENOSHA. Cooperating Agency: City of Kenosha.

Problem: To determine the best method of shore protection and
beach erosion control.

TERRITORY OF HAWAIT

WAIMEA & HANAPEPE , KAUAI. Cooperating Agency: Board of Harbor Commission-
ers, Territory of Hawaii

Problem: To determine the most suitable method of preventing
erosion, and of increasing the usable recreational beach
area, and to determine the extent of Federal aid in
effecting the desired improvement.

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