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DEPARTMENT OF THE ARMY
CORPS OF ENGINEERS

THE
ANNUAL

BULLETIN

OF THE

BEACH EROSION BOARD

OFFICE, CHIEF OF ENGINEERS
WASHINGTON, D.C.

VOLUME 14 JULY 1960

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TABLE OF CONTENTS

Sealing of Mission Bay Jetties, San Diego, Calif...... 1
Preliminary Considerations of the Use of Radioisotopes
for: aboratony tracer slechniquess. ons sete seers ei cielo ere 16
Experimental Determination of Wave Pressure Attentuation 28
Progress Reports on Research Sponsored by Beach Erosion
BOA oS ako od doco GoOOOCOoO OOOO OOO OC SKU CONDO OIE OO UD OO GOO 35
BOACHKwWERO SLON MS EUAHeS a rerranrcl we ciety clientele) ence enchedcvenctoterohenelens 42
Summaries of Reports transmitted to Congress
Pemberton Point to Cape Cod Canal, Mass. ............. 42
Wessagussett Beach, Weymouth, Mass...........-...2---- 4a
Newport Bay to San Mateo Creek, Orange County, Calif... 45
Preis quem sles Pendnsuillay seh tley ou alse rewam tera wrereenetapetcire 47
North Shore of Cape Cod from Cape Cod Canal to
PTOVAN CEE OWN. MASS avenues aes erctare ciate rey suaue ray oncitoteherelions cenebelicnen ens 49
South Shore of Long Island from Fire Island Inlet to
Montauk Porm thy tN Ye is ie ace aint chumlaieuataranmeiayre giana belle gan aredialauaica Wallattas Sei Syl
Completed Cooperative Beach Erosion Studies ............ 54
Currently Authorized Cooperative Beach Erosion Studies., 60

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SEALING OF MISSION BAY JETTIES

SAN DIEGO, CALIF.
BY

Robert E, Loudon
Assistant Chief, River and Harbor Planning Section
U. S. Army Engineer District, Los Angeles

GENERAL

San Diego and Mission Bay, California, authorized by the River and
Harbor Act approved 2h July 1916, is a project for the improvement of
the lower San Diego River for flood control and the improvement of Mission
Bay for small-craft navigation (fig. 1). In its natural state, Mission
Bay (formerly called False Bay) was a large tidal lagoon formed by a
barrier beach across the mouth of the San Diego River. The river flowed
mostly into the north end of San Diego Bay proper, until it was diked
out of the harbor in 1876, and thereafter flowed through the barrier at
Ocean Beach, The tidal flow maintained a channel about 200 feet in width
and about 8 feet in depth, connecting Mission Bay and the ocean.

The project plan provides for a river channel between two levees
about 900 feet apart which continue through the littoral zone as jetties.
The north river jetty separates the flood channel from the entrance
channel to the small-craft harbor, A third jetty, parallel to and 918
feet north of the common jetty, protects the harbor entrance channel on
its north side. Construction of the jetties was completed in 199.
Dredging of the entrance channel was completed in 1955 and the Federal
project was completed in January 1959.

In December 195), it was discovered that sand from the littoral zone
north of the north jetty was passing through that jetty into the entrance
channel, It was apparent that this was taking place over the top of the
core of the jetty, the core being composed of small stone impenetrable by
sand, In design of the jetties, the top of the core was established at
the elevation of mean lower low water (MLLW) (fig. 2). Similar design for
jetties at similarly sited harbors at Newport Beach and Point Hueneme had
not resulted in such a problem after many years of service.

In March 1955, a contract was awarded for placement of 3,000 tons of
sealing stone on the seaward slope of the north jetty within the limits
of the littoral zone, allowing the waves to drive the stone into the inter-
stices. Ninety-five percent of the stone was graded in size from 1-1/2 to
6 inches, This measure succeeded in retarding the movement of sand, but it
was later discovered that infiltration was not entirely stopped.

During the preparation in 1958 for the final dredging and revetment
contract of the project, it was discovered that 70,000 cubic yards of
shoaling material had intruded into the entrance channel northward through

the middle jetty along the littoral zone and 16,000 cubic yards had passed
through the north jetty in spite of placement of the sealing stone.
Consequently both jetties had to be sealed by such means as would produce
a permanent and completely impervious barrier.

DEVELOPMENT OF THE PLAN FOR SEALING

Figure 2 shows a typical cross section of the jetties. They are
16 feet wide at the crest, at an elevation of 1) feet above mean lower
low water, with side slopes 1 vertical on 1.5 horizontal extending to
the ocean bottom on both sides, The armor, composed of stone weighing
1 to 15 tons each, is 1) feet thick over the top of the core and about
10 feet thick over the sides of the core. The void ratio of the armor
is generally about 35 percent, but the size of individual voids range
from a fraction of a cubic foot to several cubic feet. The voids are
staggered, and only in exceptional cases would any system of voids
provide a continuous corridor between any surface and the core, which was
not constricted in many places to openings of only a few square inches.
Thus, the prevailing structural characteristics of the jetty precluded
all attempts to intrude, by action of gravity, any but the most fluid of
substances. At the same time, head differentials and dynamic thrusting
of impinging waves constantly caused water to surge back and forth
throughout the armor section with considerable velocity.

No materials were found which could be combined in any way to
provide the fluidity required for intrusion through existing voids and
still resist erosion of water in motion during the period of solidifica-
tion, It was, therefore, decided to explore the possibility of drilling
vertical intrusion holes 1) feet deep from the top of the jetty to the
core, through which grout could be introduced through an inserted nozzle.
As the drill used for this purpose would have to drop through voids and
encounter wiggling and sloping surfaces, the success of rotary drilling
was in doubt, Contractors familiar with the use of percussion drills
generally indicated their belief that the holes could be made with a
wagon drill,

MATERIALS

Grout, - After a short investigation of the properties of asphalt
mixtures, cement-sand grout with such admixtures as might be found to
produce the required characteristics was settled upon as the most practi-
cal sealing material, The grout would need to be repellent to water and
cohesive, with as little internal friction as possible; it would have to
migrate freely at low pressures with no tendency to pack, as no pressure
other than gravity head could be maintained; and it should pass freely
through short runs of pipe or hose less than 2 inches in diameter at
pressures below 200 p.s.i. in order that the rate of intrusion through
a small hole should be as great as possible, It was reasoned that large
masses of grout placed in short periods of time would suffer the minimum
erosion by surging water.

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Admixtures. - The following additives were tested as stabilizing
agents for beach sand-cement grout:

Airox pogzolan (processed volcanic tuff)
Alfesil (fly-ash)

Zeogel (barite clay)

Aquagel (bentonite)

Rotary drilling clay P-95 (Macco Corporation)
Natural sandy loam and cement

The only tests made were comparative in nature. Grout specimens were
molded in a conic frustrum 1-1/2 inches across the top, 3-1/2 inches across
the bottom, and 3 inches high. The specimens were anchored to a steel plate
with three small prongs and placed in a hydraulic flume running 12 inches
deep at a velocity of 4.5 feet per second. Time of immersion and loss of
material were as tabulated below:

Test No. Mixture Immersion time Loss (4)
1 0.95 1b. beach sand 52 seconds 100

0.47 1b. cement
0.10 1b. airox pozzolan
0.52 Ib. water

2 0.95 1b. beach sand 1 minute 75
0.30 1b. cement
0.20 1b. airox pozzolan
0.35 1b. water

3 1,00 1b, beach sand 1 minute 92
0.30 1b. cement
0.30 1b. alfesil
0.22 1b. water

h 1.00 1b. sandy loam 1 minute 55
0.22 lb. cement
0.27 1b. water

5 1.00 1b, beach sand 1 minute 1.8
0.30 1b. cement
0.30 1b, aquagel
0.51 1b. water

6 1.00 1b. beach sand 1 minute ALA 7/
0.30 1b. cement
0.30 1b. P=95 rotary clay
0.31 1b. water

7 1.00 1b, beach sand 1 minute 1.5
0.30 1b. cement
0.30 1b. zeogel
0.59 1b. water

8 1.00 1b. beach sand 2), minutes (isos
0.30 1b, cement
0.30 1b. P-95 rotary clay
0.31 1b. water
4

The results of the tests shown above indicate that only the aquagel,
rotary clay and zeogel contributed materially toward making the grout
cohesive and resistant to erosion during the presetting period, Grout
with the clays added, exhibited characteristics similar to those of
pure clay. These properties were attributed in part to the smallness
of the beach sand particles because the small particles cause less
interruption of the micellar bonding forces of the clay, Thus, the
attraction between water films toughened by valence bond created a
grout of high plasticity.

Materials selected, - P=95 drilling clay, said by the refiner to
be the micaceous fraction of illite, mined at Muroc Dry Lake, Calif.,
was selected as the stabilizing admixture to be used in the grout because
it produced a harder concrete than the other clays. Hardness, more than
strength, was desired because the concrete barrier would be exposed to
sea action in places and there would be some abrasive effect upon surfaces
exposed to sand particles in the attacking waves, Standard test cylinders,
cast with materials proportioned as in test No. 8, tested 1,140 p.s.i. at
1; days. Mojave clay, similar to P-95 was used in the final construction.
Both Mojave clay and P-95 are derived from illite, The illite clays were
used only because of availability and suitability, Certain other clays
would probably be just as suitable. Clays used for the purpose should be
highly plastic and should homogenize readily in mixtures.

EXPERIMENTAL CONSTRUCTION

An experimental contract was awarded for sealing a short reach of
the middle jetty in December 1958. The contract provided for placement
of 00 cubic yards of grout in the reach of the jetty passing through the
surf zone, The specifications provided for the use of materials, equipment,
and methods as determined and ordered by the contracting officer, Contract
bid items were set up on the basis of operations and materials anticipated,
Major bid items were for (a) moving drilling equipment, (b) drilling 2-inch
grout holes, (c) pressure grouting, and (d) furnishing portland cement.
Clay and calcium chloride were Government furnished,

The contractor moved to the job site in January 1959 with the follow-
ing major items of equipment,

1 = 2-c.y. fixed drum plaster mixer,
1 =- l-c.y. fixed drum plaster mixer,

1 - )80-1b. wagon drill with 2=inch silicon-
carbide bits,

1 - 00 c.f.m,. portable air compressor.
) = Simplex air-driven reciprocating grout pumps.

1 - High pressure centrifugal water pump for flushing
sand as encountered lying on top of the jetty core.

1 - Tank wagon to transport mixing water,

Drilling. = The wagon drill was successful in drilling the grout
holes although, in some locations, loose spalls wasted during the jetty
construction in the capstone voids made drilling difficult by jamming the
drill, Repeated withdrawals of the drill, before jamming took place, would
finally pulverige or kick aside the spalls, leaving a workable hole. The
rock was quite hard and the bits had to be sharpened after about 3 hours of
operation. Holes were spaced approximately 8 feet apart, 55 holes being
drilled along the center of the jetty in a reach of hls feet. In som
places, the holes did not drill true and had small offsets across the voids
encountered. In these cases, rubber hose was substituted for the rigid
grout nozzle used on true holes,

Mixing and placing. - The mixer was set up on the beach berm, safely
above the high tide about 200 feet south of the jetty (see fig. 2,
Ingredients other than sand and water were brought to the mixer in bags
and charging was done by hand, The sand was initially piled near the
maker with a dozer and then measured and put in by wheelbarrows. Mixing
water was hauled by tank truck from a temporary fire-hydrant service
provided by the city. From the mixer, the grout was fed into a funnel
at the intake of a Simplex grout pump and pumped through a 2=-inch pipe
line to the holes, A booster pump was required every 250 feet in order
to propel grout of the required stiffness through the line. At the end
of the line, about 30 feet of 1=-1/2-inch hase led to the nozzle which
was a 15-foot length of 1-1/2-inch pipe. The nozzle was inserted to the
bottom of the hole and withdrawn at such a rate as to form an imagined
cone extending from MLLW (top of core) to 10 feet above MLIW wherever
possible, The theoretical intersection of the cones between holes was
assumed to bring the barrier to +6,0 MLLW elevation. From 6 to 9 cubic
yards of grout were intruded into each hole. Where crooked holes did
not permit use of the rigid nozzle, the 1-1/2-inch hose, stiffened by a
rod inside to prevent veering off into voids, was inserted directly into
the hole. An average of 18 cubic yards per working day was placed.

OBSERVATION, CONTROLS, AND INSPECTION

The writer was in direct charge of the inspection and administration
of the experimental contract and spent about 15 days at the site during
the construction period of 57 calendar days. Monitoring the results was
difficult and in large part stochastic. The exterior of the jetty did
not supply enough "windows" through which to watch the migration and
stacking of the intruded grout. Interior conditions before grout place=
ment could be partially appraised by probing with a rod, In certain deep
surface voids and fissures in the jetty slopes, it was possible to
determine the whereabouts of the grout when it migrated to the outside
limits of the jetty, Flashlight and probing rod were of assistance here
also. In certain deep voids extending to the core, the grout could be seen
to congeal and stop flowing in openings as large as a foot or more in
diameter - a gratifying sight; more gratifying when the same condition was
observed after the tide had dropped and the waves had ceased their attack,
leaving the fresh grout surface only pitted and not eroded.

It was decided that core sampling would probably not be possible
and if it were, the samples would produce no definite measure of the
effectiveness of the sealing. A few exploratory holes were made with the
wagon drill between grout holes, and most showed that the voids penetrated
were filled as expected. Prior to commencement of work, flourescent dye
was placed on the ocean side of the jetty and the time required for colored
water to show upon the opposite side was recorded. This required from 10
to 20 minutes. After sealing, the test was repeated and in only one place
did color come through the jetty. Investigation of this spot proved the
existence of non=-continuity of the barrier which was corrected by drilling
another grout hole and intruding additional grout.

Before sealing started, there was a trench-like depression in the
beach contiguous to the outside (away from the channel) toe of the jetty,
where beach and jetty met. This depression was about 10 feet wide and
about 2 feet deep near the mean high water line, becoming progressively
shallower and fading out at about 2 feet below MLIW (see fig. 2 and
photograph )}). This was an ostensible indication that sand was passing
through the jetty. As sealing progressed seaward, the depression filled
and sand piled against the jetty to heights up to 1.5 feet above the
average beach, Also, the beach as far as 150 feet away from the jetty
began to gain in elevation, This seemed to be convincing evidence that
the sand was now being stopped from moving through the jetty.

Batching control, - The wheelbarrows were calibrated and used as
measuring boxes for the sand, loads being struck at all times to assure
uniformity. This method was of sufficient accuracy as the moisture content
of the sand was small and remained nearly constant. Water was measured by
a meter installed on the mixer, Cement was supplied in bags of 9h pounds,
and clay in bags of 100 pounds, The mix was set up so as to avoid using
partial bags. Proportions used are as tabulated below. Two pounds of
calcium chloride per sack of cement were added to accelerate the set.

One cubic yard mix

Sand scieic cisiclcieisisicleicicciciovciee OOO pounds
Cement, GySACKSereicielcisicielennine pounds
Clay, h SaCKSeecececcccce 00 pounds
WATE? cislcrcreretercie wiovelereinioieloies 8.6 cubic feet
Calcium chloride...ccccee 16 pounds

These proportions differ from those shown for No. 8 of the tests, but it
was desired to use only enough clay to produce the required plasticity in
order that the concrete would be as hard as possible. This mix was ideal
for most conditions encountered although it caused the pumps to work at
their utmost,

Placement control, - Placement of grout was always observed closely.
Withdrawal of the nozzle was adjusted by observing the migration of the
grout as described earlier. In cases where it was impossible to see the
grout at all, the hole ahead of the one receiving grout was probed for
appearance of grout, Grout was usually allowed to build up to about 3
feet in depth in the hole ahead before withdrawing at a location and
moving forward,

FINAL CONSTRUCTION

In April 1959, a contract was awarded for sealing an additional 880
feet of the middle jetty and 1,000 feet of the north jetty (see fig. 2)
Specifications were prepared on the basis of what was learned and proved
during the experimental construction. Procedures on the final construction
differed little from those on the experimental construction, although the
equipment used was superior.

A batching and mixing plant especially for the job was built By the
contractor. The mixer consisted of twin 1/2-yard plaster mixers discharg-
ing into a shallow hopper, mounted directly underneath, which funneled the
grout into a valveless rotor-stator positive action pump. The assembly
was mounted on a car which ran on a railway constructed on the jetty top.
Likewise, an endless belt elevator mounted on railway trucks, elevated the
dry ingredients of the grout into the mixer as they were placed at the
lower end of the belt by hand. A sand hopper, also mounted on a car, ran
back and forth from the beach to the elevator. Rotary gates released
sand into a measuring vessel, swung on trunions, which fed the sand onto
the belt directly from the bags. The discharge end of the elevator could
be continuously charged and discharged,

A mine air hoist was rigged at the land end of the rails and, with
a closed loop rove through a snatch block placed at the sea end of the
rails, moved the mixer and wagon drill as needed, and also shuttled the
sand hopper from the stockpile to the mixer.

The wagon drill was mounted on a car which ran on the rails, and
2-1/2-inch detachable silicon carbide bits were used. Spalls and loose
rock, encountered in the drilling, sometimes hampered the work and some
holes had to be abandoned and relocated.

Materials. - Materials used in the final construction were the same
as in the experimental construction, The clay used was similar to the
P-95 rotary drilling clay used in the experimental construction. This
clay was mined at Muroc Dry Lake, California, as was the Macco P-95,

Mixing and placing. - The grout was mixed at the point of deposition
and was not pumped farther than 25 feet to the nozzle. This method allowed
the grout to be severely stiffened by reduction of water whenever large
openings to the outside of the jetty were encountered, The nozzle consisted
of 1-1/2-inch rigid pipe. The holes were drilled much truer on this job
than was done on the experimental work, so it was never necessary to use a
flexible nozzle. Batching measurements were made volumetrically. Sand
was measured by a calibrated steel vessel under the hopper, and water by
a meter installed at the mixer. Cement and clay were delivered in sacks.

Removal of sand prior to grouting. = In the reaches of the jetties
opposite beaches above MLLW in elevation, as much as a foot of sand was
found to be stacked on top of the jetty core. This sand was removed at

each hole by flushing with sea water at high pressure. A piston pump
of hO gepem. capacity was provided for this purpose.

Power. - The collection of equipment used by the contractor was
powered several ways. The mixer and pump, and the elevating belt were
driven by electric motors. Compressed air drove the wagon drill and
mine hoist. Water pumps were driven by gasoline engines, Electric
current was supplied by a 50-kw portable generator, and compressed air
by a 600=-c.f.m. portable air compressox.

EVALUATION

The method herein described, for sealing the Mission Bay jetties,
is believed to have been successful in stopping the passage of sand into
the navigation channel, Surveys through November 1959 indicate no further
incursion of sand. Surveys as well as visual inspection show that a
shoulder of sand along the channelward toe of the jetty, much in evidence
before sealing, has disappeared since the supply 6f intruding sand has
been cut off. Wave action and tidal currents have carried this surplus
sand to the channel slopes in deeper water,

There is little doubt regarding the permanence of the work. Specimens
of the grout immersed in sea water for 8 months show no indication of
disintegration from sulphides or other chemicals contained in sea water.
The very low porosity of the concrete seems to exclude water entirely.
Tests cylinders cast during construction tested 2,200 p.s.i. at 100 days
and the hardness of the concrete is estimated to be above 3 on the Mohs
stale. Serious abrasion by water-carried sand is not likely as, on the
channel side, the attacking waves should be clear water, and on the beach
side, sand thrown into the interstices by the waves should remain in
sufficient quantity to form a cushion over exposed surfaces which would
prevent serious erosion of the concrete. For best results, work of this
type should be done during favorable tides and moderate sea action,

Cost. = It has been calculated that the work under the experimental
contract cost about $67 per linear foot of jetty, and the final work,
about $1 per linear foot, with combined costs amounting to about $)5
per linear foot. An average of 1.06 cubic yards of grout per linear foot
was placed and the average spacing of holes was 6.3 feet.

In the case of Mission Bay, ang shoaling in the outer entrance
chamel results in nuisance and hazards to the navigation of small craft
because shoals cause chaotic and breaking waves. Between 1955 and 1958
shoaling took place at an annual rate of 5,000 cubic yards. The only
conclusion compatible with other facts was that all of this sand was
finding its way into the channel through the jetties, To maintain project
depth without sealing the jetties at this shoaling rate would require
dredging anmally at a cost of about $40,000. If this shoaling has been
prevented or even reduced to minor quantities, the cost of sealing the
jetties will be justified.

PHOTOGRAPH 1

Experimental contract.
Booster pump.
Mixer in background.

PHOTOGRAPH 2

Experimental contract.
Intruding grout through
flexible hose.

10

PHOTOGRAPH 3

Observing grout in a deep void.

PHOTOGRAPH 4

Experimental contract.

Wagon drill on jetty.

Note the depressed beach along
the jetty before sealing.

Vl

PHOTOGRAPH 5

Experimental contract.

View of grout line and booster pump.
Line was laid on the beach 2 days
before photo was taken. Note how

the beach is building up in foreground
covering pipe. Jetty in foreground
has been sealed.

PHOTOGRAPH 6

Flash photo of grout
extruding from large
opening. Dark area
above the lath jammed
in crack is surface of
congealed grout mass.
Entire picture covers
exterior of large void
6 feet within jetty
slope. Photographer
crawled through small
hole into larger void.

PHOTOGRAPH 7

Flash photo of congealed
grout mass in void similar
to photograph 6,

PHOTOGRAPH 8

Final contract.
View of mixer, sand hopper, elevating belt,
electric generators, and railway.

PHOTOGRAPH 9

Final contract.
View of sand hopper, mixer,
and wagon drill.

PHOTOGRAPH 10

Final contract.
Close-up of mixer.

PHOTOGRAPH 11

Final contract.
Close-up of wagon drill.

PRELIMINARY CONSIDERATIONS OF THE USE OF RADIOISOTOPES

FOR LABORATORY TRACER TECHNIQUES

by

Norman E, Taney, Chief
Geology Branch, Engineering Division
and Radiological Control Officer
Beach Erosion Board
U. S. Army Corps of Engineers

An investigation of the feasibility of utilizing radioactive tracers in
laboratory studies of sediment movement has been in progress for the past Sev-
eral years at the Beach Erosion Board, The preliminary results of this investi-
gation are presented herein.

The responses of beach and bottom sediments to wave and current energy are
incompletely understood, and many facets of these complex phenomena are dealt
with empirically, It is necessary, therefore, to measure the resultants of
the interaction of sea energy and the shore upon which it impinges to augment
our fund of knowledge and solve practical problems, Such measurements, however,
may be most difficult to acquire.

The measurement of direction, velocity and quantity of sediments moving in
the littoral zone may be quite complex, particularly in areas where there are
no structures which block essentially all sediment movement, It is, therefore,
most desirable to mark sediments or simulated sediments in some fashion which
will permit convenient and rapid identification of the labelled particles,
A method which has been developed in the past decade involves the use of radio-
isotopes, The radioactive material is fastened on or in the sediment or simul-
ated sediment and the quanta emitted are detected by some suitable means, Such
a procedure is most advantageous in that the particles are in their normal en-
vironment and respond normally to the forces applied. Detection of the particles
is possible on subsequent days and thus a time-space history of the particles
may be developed. Such a program is based upon the positive identification of
the radioactive emissions and may be pursued without a laborious and expensive
bottom sampling program, This does not mean that bottom samples are not required,
rather it means that the expensive, time-consuming acquisition of samples is
minimized

Labelled sedimentary particles may also be used advantageously in the
laboratory, At the Beach Erosion Board the Shore Processes Test Basin is a
facility which could be utilized for radioactive tracer techniques, It is
a shallow concrete structure 300 feet long, 150 feet wide and 3 feet deep, At
present the basin is divided into three parts for three concurrent tests,
Figure 1 illustrates a typical test layout in one section of the basin, The
wave generating machines are synchronized so that a single wave leaves the

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machines for each stroke of the generating blades, The wave period is changed
at some predetermined interval (usually every 15 minutes), a Sequence of three
different periods generally being used during any testing program. Asa
consequence of changing the wave period the wave amplitude also changes, The
Sandy beach and bottom sediments are moved in the downdrift direction by the
natural forces cauSed by the waves, Additional sand is added at the feeder
beach area to maintain the position of the still water line. Generally the
tests are 50 hours long (this means 50 hours of wave action on the beach with
time for hydrographic surveys and other necessary details excluded from the
wave-generation period), Shorter tests have been made in about 25 hours, while
some long tests have taken in excess of 300 hours of operating time,

It is beyond the scope of this paper to discuss the objectives of a labora-
tory testing program, but it is proper to elaborate upon some of the goals which
may or can be achieved with the use of radioactive tracers, and which are diffi-
cult to develop by normal testing. One such objective would be the determina=
tion of the velocity with which individual particles move, Depending upon the
sensitivity of the detection system and the concentration of activated particles,
it is conceivable that the presence of a very few particles may be detected in
place, On the other hand, the utilization of autoradiographic techniques and a
minimum sampling program should permit the identification of a single particle.
Knowing the spatial distribution of the samples and the time history of the test
the rate of travel of the particles is then also known, It is also feasible to
discover the size of the activated particle by measuring the intensity of the
activity emitted by the particle, This could be done by calibrating particle
activity versus size (to be discussed later) for some fixed exposure time of
photographic film,

Another objective which appears feasible is the definition of the zone of
sediments disturbed by the wave action, This zone may be defined by its origin,
As a deep water oScillatory wave passes through continually shallowing waters in
its approach toward land, the orbital velocity of a water particle becomes
sufficiently great to affect the sedimentary particles of the bottom, Under some
given conditions of wave amplitude and period and at some fixed depth it would
appear that the first effects of the orbital wave velocity are upon a layer of
sedimentary particles one particle thick, In this layer some few particles would
be thrown up into suSpension by the wave action and others would be moved by
saltation and/or creep. As the water depth becomes increasingly shallow and as
waves approach the breaking zone, more of the bottom sediments are disturbed and
eroded, It is readily apparent that the increase in the number of sedimentary
particles set into motion must be cauSed by an increase in depth of the zone of
sediments disturbed by wave action, In the breaking zone the extreme turbul-=
ence of the breaking wave draws sedimentary particles of all sizes into suspension
and it is here that the greatest concentration of suspended sedimentary particles
occurs, As the wave becomes a wave of translation the turbulent action of the
wave continues to move the bottom particles by any or all of the three modes of
transportation mentioned above and the zone of sediments disturbed by wave action
is found to continue to the limit of wave uprush, It is readily apparent that
the areal extent and the depth of this zone of disturbed sediments is responsive
to the wave climate occurring at the time, and changes as the wave conditions
change, It is believed that the definition of the areal extent and of the depth
of this zone can be made with the use of labelled sediments, A combination of
in situ monitoring, surface samples and subsurface cores should define this zone,

The goal of many laboratory experiments is a quantitative relationship of

18

sediment movement versus wave energy. While it is not clear whether such a
relationship may be achieved, the addition of data such as described above
and other measurements not feasible by normal testing procedures may lead to
the development of the desired relationship,

The techniques by which activated material could be monitored in the
laboratory are basically twofold: in situ measurements and laboratory measure-
ments of samples taken from the test area, A Sampling program is feasible for
laboratory studies but such a program becomes enormously expensive if pursued
during a field test. Consequently, it is desirable to design laboratory studies
which utilize in-place measurements extensively and to supplement these measure=-
ments with a sampling program, The design of field applications would of course
minimize the use of sampling, In this fashion it will be possible to gain valu-
able experience from laboratory studies which may be applied to field techniques
when working in a littoral environment,

The physical detection of the emitted quanta is a typical gamma photon
detection system which includes a stable high voltage supply, detector, linear
amplifier, pulse height analyzer, and scaler, A 2 x 2-inch sodium iodide,
thallium activated crystal and a photo-multiplier tube are the heart of the
detector. A detector developed at the University of California for the San
Francisco District of the Corps of Engineers will be utilized in the first
studies, The remaining components are available commercially.

One factor of critical importance in any test which uses radioisotopes as
tracer materials is the selection of the vehicle to carry the activated material,
The most obvious and moSt important criterion is that this vehicle must behave
in exactly the same manner as do the natural sediments, The other equally ob=
vious and important criterion is that no hazard should result from the use of
any vehicle or carrier, It is apparent therefore that the optimum carrier
would be the natural sediments, provided that a representative size distribution
of the sediment was obtained for irradiation, There are problems, however,
associated with this technique. Goldberg and Inman (see bibliography) attempted
this technique and were in fact able to irradiate the local sediments and de=-
tect irradiated particles, Neither the silicon nor the oxygen of the normal
quartz sand were detected however, as both these isotopes have unusably short
half lives, The radioisotope which was detected was phosphorous (P32) which
was present as an impurity in the sedimentary grains, Inasmuch as phosphorous
is a beta emitter, and beta particles are attenuated rapidly an extensive
sampling program was necessary, Several techniques have been suggested by
which the natural sediment will sorb the radioisotope, Gibert has precipitated
Silver (Ag110) on natural sand grains, Eakins and Smith suggested Gu eT
natural sand before sorption was attempted and Krone has sorbed gold (Aul?8)
on the muds and silts of San Francisco Bay. Gibert*s technique requires ex=
tensive sampling and extensive laboratory procedures, The particles suggested
by Eakins and Smith may sorb the irradiated material differentially and thus
not be representative of the natural sediments, and the muds and silts of Krone
are not usually the predominant material found in the littoral zone, Al11 of
the methods mentioned above, aS a consequence, appear to have severe limita=
tions,

Another approach has been the utilization of an artificial carrier which
simulates the natural sediments, Glass has been the material most popular in
the past, Inose, Kato, Sato and Shiraishi used glass in Japan; Putman and Smith;

and Putman, Smith and others used glass as a carrier in England. Steers

and Smith utilized cement to simulate pebbles and Ariman, Santema, and Svasek;
and Ariman, SvaSek and Verkerk mention the use of zeolites to simulate sand
which becomes activated through ion-exchange techniques.

When uSing some material to simulate the natural sediment it is required
that the material possess the physical and chemical characteristics of the
natural sediments and, also, that this simulated material react in the same
fashion as do the natural sediments to the wave and current energy affecting the
particles, ThesSe criteria may be broken down as follows:

a) The density of the particles must be the same as that of the
natural sediments (excluding the presence of heavy minerals normally found in
natural sediments),

b) The particle size distribution as determined hydraulically should
be the same as that of the natural sediments,

c) The shape of the particles (the roundness and sphericity) should
closely simulate that of the natural particles,

d) The hardness of the simulated sediments should be the same or
nearly the same as that of the natural particles,

e) The chemical properties of the simulated sediment should be such
that there is no reaction between the artificial carrier and sea water nor with
those sedimentary particles normally present.

Glass appears to possess all of the necessary characteristics, A boron
free soda-lime-silica glass with lead added to obtain the proper density could
be used as both the carrier and radioactive tracer, The sodium (Na“*) has a
haif life of 15 hours and is applicable as will be shown later, It is also
possible to consider a high silica glass, again with lead added to obtain the
proper density, and the addition also of some small percentage of the tracer ele-
ment directly to the glass prior to melting, In this fashion a homogeneous
glass with density 2.65 or 2,66 grams per cubic centimeter may be achieved in
which the tracer element is completely and uniformly dispersed throughout the
glass. Grinding the glass will produce particles with low sphericity and round=
ness, but it is believed that passing the particles over a flame will cause both
roundness and sphericity to increase and thus satisfy the shape requirements.
The particle size distribution of the glass can be controlled very closely prior
to its irradiation such that the simulated sediment will be identical with,
within experimental error, the natural sediment. Finally the glass is sufficient-
ly inert chemically to cause no problem,

The choice of label, the element incorporated in the glass which is to be
detected, is dependent upon a number of factors; these are the type of emission,
the energy of the emission, the half life, the chemistry of the element and
the expense of preparation, The optimum radioactive label is one which may be
easily detected and which will last long enough for the purposes of the experi-
ment or test, Under the conditions of the test, briefly described earlier, it
is necessary that the radioisotope emit gamma photons rather than alpha or beta

20

particles, The reason for this is that alpha particles might never escape

the labelled simulated sediment due to self-absorption or the particle

would be degraded by interaction with surrounding matter very rapidly in rela-
tively minute distances, consequently, an alpha particle would not be detected,
While a beta particle does have a longer useful path than alpha particles,

beta particles are also rapidly attenuated, Further beta particles display a
spectrum of energies ranging from the high of any given radio element downward,
Gamma photons, on the other hand, have constant energy upon emission and are
not attenuated nearly as rapidly as either alpha or beta particles, Asa
consequence gamma photons are detectable even when the labelled particle is
covered with sand and/or water, That is te say between the labelled particle
and the detector there are some sand grains and water, With respect to the
energy of the photon, it is advantageous that the gamma photons have energies
of 1 Mev or more, in order to facilitate transmission and reduce attenuation

to a minimum, Another advantage for seeking a radioisotope which emits a

gamma photon of high energy is that during detection (when using a single channel
pulse-eight analyzer in the system) the natural background in the 1 Mev or
greater range is much lower than is found with lower energy photons,

The normal 50-hour test described earlier requires approximately 3 weeks of
operational time, This fact has, of course, a very strong influence on the
choice of radioisotope, For safety reasons it is desirable that no more than
approximately 50 millicuries of radioisotope be used for any test. These two
parameters (50 millicuries of activity and 3 weeks of test time) strongly suggest
an isotope with a half life of approximately 60 hours, If such an isotope
is chosen and the labelled simulated sediment placed upon the beach and bottom
Sediments at 8 A, M,. on Monday and at this time the activity is 50 millicuries,
then 3 working weeks or some 456 calendar hours later, the remaining activity
is approximately 0,25 Millicurie and in one more calendar week the remaining
activity is approximately 35 microcuries, Such an arrangement is desirable
in that at the end of 3 weeks the remaining activity will be on the order of
the minimum detectable amount and in one more week another test could be started
without serious interference from the activity of the prior test. If the test
were 2 weeks and 50 millicuries of activity were used then the suggested half
life becomes approximately 40 hours, Thus for a 2-week period or 288 calendar
hours the activity remaining the last day would be approximately 0.35 millicurie
and one week later the remaining activity would be approximately 20 microcuries,
Tt can be readily seen, therefore, that half life is of critical importance in
the choice of the radioisotope.

The chemistry of the element chosen must permit the element to be homogen-
eously dispersed throughout the glass without any reaction with the glass, Fur-
ther it is necessary that once included in the glass the material will not be
leached out of the glass by the surrounding water.

A final criterion in any test of this sort is the economics of the test
for it is common knowledge that desirable tests are sometimes delayed by un-
favorable economics, The costs of those parts of the test which are discussed
in this paper are most reasonable, The special density glass may be prepared,
ground, rounded and analyzed by spectrographic means for approximately $250,
The irradiation of the glass and activation of the tracer element is a service
irradiation which costs on the order of $100, Miscellaneous expenses such as

2l

packaging and shipping costs should not increase the total cost to more than
$500. The expense involved in a normal 50-hour test which requires approximate-
ly 15 working days to complete is of the order of $4,000, This figure includes
plant rental, power and labor charges, Thus for an increase in cost of $500.

to the normal cost of $4,000 a labelled sediment may be added to a test. The
figure appears most reasonable,

The choice of a specific isotope depends upon the purpoSe and the length
of the test. Generally if a test were to last 2 or 3 calendar weeks (5 working
days per calendar week) then optimum half life would be respectively 17, 31 and
65 hours, In this fashion it would be possible to detect the radioisotope for
the duration of the test and approximately one week later the activity would
have essentially disappeared by normal decay, The exception to the above state=
ment is that as the test period increases in time and consequently the desirable
half life also increases it takes longer for the remaining activity to decay to
negligible amounts, Table 1 lists those radioisotopes which appear feasible
for testing programs of 1, 2 and 3 weeks.

TABLE 1
Atomic Mass Half Life Radiation Energy
Isotope Numbers Numbers in Hours Beta Gamma
Gallium 31 72 14.3 3015 ,2652,1.5, 10,84,0.6-2651
0.9,0.6
Sodium 11 24 USS ORL SS9 1037,2.,76
Praseodymium 59 142 19,2 2,15,0,64 0.135,1.59
Lanthanum 57 140 40.0 1,32,1.67,2.26 1,6,0,093 =3,0
Gold 79 198 64.6 0,963 0.41,0.68,1.1

The safety consideration is probably the single most important factor
of the design of any test utilizing radioactive material, While detailed
safety considerations do not fall properly within the scope of this paper, the
importance of the subject does justify some comments upon hazard evaluation,
In any testing program which might be considered, several factors tend to
reduce any potential hazard, Assuming a total activity of 50 millicuries
were to be used at the beginning of the test and that this radioactive material
would be homogeneously dispersed over an area of some 30 to 50 square feet,
the activity per square foot would be approximately 1,66 to 1,0 millicuries
per square foot, The greatest portion of this activity would have shielding
above it, that is the water layer which would cover the natural sand bottom
under the conditions of the test, As the model beach is subjected to the
action of the waves there would be a relatively rapid dispersal on the active

22

grains in one of several fashions: either the grains would be moved in the
direction of the longshore drift or in the offshore direction, or other grains
would cover the stationary irradiated glass particles, In this fashion there
would be dispersal of the activated grains and dilution of those particles by
non-activated sand grains, Another factor would be the relatively rapid decay
of any of the tracer elements chosen for this type test. For a l-week testing
program for instance, in 1 day the activity would be reduced to less than half
of the original activity present. Another factor is the physical conditions

of the test, The arrangements are such that at no time would personnel be re-
quired to walk on the sandy beach nor would it be necessary for personnel to

be closer than 1 meter to the area where the activated material was placed,
Pinally the time required for necessary measurements during the course of the
test is small, probably on the order of 1 hour per day or less. In this fashion
natural decay, time, distance, and dispersal of the particles all tend to reduce
potential hazards,

The evaluation of potential hazard has been made by the method suggested
in a paper by Hubbell, Bach and Lamkin, The conditiOns which would exist in-
volve the utilization of 50 millicuries of sodium (Na24) dispersed uniformly
over an area 1,5 feet wide by 30 feet long, As it is desirable to evaluate the
hazard under the worst conditions, it has been assumed that no water, which
would act aS a Shield, covers the radioactive particles, Purther, the evalua-
tion was made for that time when the irradiated glass has just been placed upon
the beach, The reasoning behind this assumption is that the activity would
rapidly decay as the test started and continued, and there would be dispersal
of the activity. The evaluation is basically a problem of summing up the con-
tributions from all of the photons emitted by the irradiated particles which
reach the detector and then converting this energy to doSe at the position of
the detector, The dose has teen calculated for a detector positioned at an ele-
vation of 3 feet above beach level, the height most commonly considered if
personnel will be affected.

The dose rate was first calculated with the position of the detector 3
feet above the center of the rectangle, The summation is facilitated by the
use of a Legendre expansion which takes the form:

Reo NM ae
ONS ie Gin

+ (AQ > 2A, * 2 + LA, )qQ Tt?

Pelt =) SAGfect inSs gh weg AS ime Sie ele neal AG) nGaatis
ss (Gaunt) Loy ek VO Shei LAI eye
2 Uv ese OA ols 6) 0 8 RS). digit?
A

The response of the detector to radiation from a contaminated surface (I) is
dependent upon the intensity of the unscattered and scattered radiation (A's),
the attenuation of photons in the energy absorber (T) and the geometry effects
(q). Because sodium (Na24) emits two photons 100 percent of the time, the
mathematics for calculating the detector response, after substitution of the
appropriate coefficients, has the following appearance:

23

ITeI 1 x 0.27263

A SY/

+
(=
R
q

04879 | ( = 0,.46120)(0.00604)

(2)(0.879) + (2)(0, 143) | (0.50000 ) (0.00604)?

=
i]

+
=
4

(3)(0.879) + (3)(2)(0.143) - (3)(2)( ~ 0,00239)]

(- 0.46397) (0,00604)°

+

E = (4)(0.879) + (4)(3)(0.143) - (4)(3)(2)¢ = 0.00239) ]

(0,38944)(0,00604)*

+

E ~ (5)(0,.879) + (5)(4)(0,143) = (5)(4)(3)( - 0,00239)|

( = 0.29404) (0,00604)°
Wt2 576 sa 027263
+

1l- 0,699 | ( = 0.46120)(0,00413)

1 (2)(0,699)+(2)(0,026) | (0,50000)(0.90413)2

+
SS

1 = (3)(0,699)4(3)(2)(0,026) = (3)(2)¢ = 0.001045) |
( = 0.46397)(0,00413)
: E ~ (4)(0,699)+ (4)(3)(0.026) = (4)(3)(2)
( = 0.001045) | (0.38944) (0.00413)
+ E = (5)(0.699) + (5)(4)€0,026)~(8)(4)(3)(=0,002045) |
( = 0.29404) (0.00413)>
After combining terms the solution is shown below:
IT=14.37 ~ 2.7263 x 107! -3.37 x 1077=8,59 x ‘or +7.83 x 1078 -

10 , 9.28 x 107}3

3.86 x 10°
=] =4 =6
+ I .76 ~ 2.7263 x 10°- - 5.73 x 10 = 2,95 x 10 telat
1078 - 1.652 x 10719 + 6.78 x 10713
It may be seen readily that the contribution from all terms below the
second term are negligible due to the geometry of the particular configuration;
therefore only the first two terms are used for further calculations,

Once the detector response has been calculated, the dose rate may be
calculated as follows:

24

Bs o 11,37 rn Y Beote
= Dy .37 + D2.76 od an AG

where D = dose rate at detector (photons / sec)

cm

I = detector response (from above)

< = surface density of contaminant in

an photons per unit time from a unit
surface area into a unit solid angle
and 0 = activity (in curies)

(area of rectangle)(conversion factor cm-/f t2)

After substitution of the proper values and the performance of the indicated
mathematics the results are shown below:

Die Diy 9) Dole) = see4ix 10° 413.830 x10"

The final calculation of absorbed dose at the detector is made with the
following equation:

absorbed dose

absorption coefficient
for water (cm2/g)

EB, = initial energy of photons
D flux from above

where De
Ba

The result of the above calculation may be converted to rad/hr by the use of
energy and time conversion factors. Finally the total dose at a point 3 feet
above the center of the rectangle is equal to:

D, =D.1.37.. + Dzo.76 = 0.0233 rad/hr

It is also desirable to calculate the dose rate at some position to the side

of the contaminated rectangle, This has been done for a detector position 3
feet above beach level, 1,5 feet to the side of the rectangle, and 3 feet

from the end of the rectangle, The reason this calculation has been made is
that this is the most probable position in which a man would be standing during
the course of a test. The absorbed dose rate (D,) in this position is equal to
0.01809 rad/hr, The above dose rates appear to indicate that with normal
precautions a test of the type suggested above is well within proper safety
limits,

The author gratefully acknowledges the assistance of C, Eisenhauer and

J. Hubbell of the National Bureau of Standards without which the above calcu-
lation of the absorbed dose rate could not have been made,

25

Several conclusions appear self-evident concerning the use of radioactive
tracers to follow the movement of natural sediments, It appears that the
addition of radioactive tracers will be an invaluable tool to determine or make
possible measurements which heretofore have been impossible or extremely
difficult. The use of glass to simulate the natural sediment appears quite
feasible and the use of Sodium, lanthanum or gold for respectively tests of 1,

2 and 3 weeks is feasible, Finally, the experience and knowledge of techniques
gained from laboratory testing will be of invaluable assistance for future field
operations,

26

BIBLIOGRAPHY

Arlman, Joe Je, Santema, P., and Svasek, Je No, "MOvement of Bottom Sediment
in Coastal Waters by Currents and Waves: MeaSurements with the
Aid of Radioactive Tracers in the Netherlands”, U, S, Beach
Erosion Board, Technical Memorandum No, 105, February 1958,

Ariman, J. Jo, Svasek, J. No, and Verkerk, B., "The Use of Radioactive
Isotopes for the Study of Littoral Drift", The Dock & Harbour
Authority, Vol. 41, No, 476, June 1960,

Gibert, A.,"Essay on the Possibility of Using Silver 110 in the Study of
the Transportation of Sand by the Sea", Laboratorio Nacional de
Engenharia Civil. Publ. No. 63. Lisbon, Portugal, 1955,

e ce © ce oe Observations on Sand Movement under Sea Water with Radioactive
Silver Ag 110", Atome et Industrie, Geneva, Switzerland, 1959,
(No, IV/C/17/1 Radio elements), In French,

Goldberg, D., and Inman, D, L., “Neutron-Irradiated Quartz as a Tracer of
Sand Movements", Bulletin of the Geological Society of America,
Vol. 66, May 1955,

Hubbell, J. H., Bach, R, L., and Lamkin, J. C., ‘Radiation Field From a
Rectangular Source”, Journal of Research of the National Bureau
of Standards - C, Engineering and Instrumentation, Vol, 64C,
No, 2, April-June 1960,

Inose, Kato, M., Sato, S., and Shiraishi, N., "The Field Experiment of
Littoral Drift Using Radioactive Glass Sand", International
Conference on the Peaceful Uses of Atomic Energy, Japan, July
1955, (A/CONF, 8/P/1053).

Krone, R. B,., "Silt Transport Studies Utilizing Radioisotopes", Annual
and Quarterly Progress Reports, University of California
Institute of Engineering Research, 1957=1960,

Putman, J. L., and Smith, D. B., "Radioactive Tracer Techniques for Sand
and Silt Movements Under Water”, International Journal of Applied
Radiation and Isotopes, Vol. 1, Nos, 1/2, July 1956.

Smith, D, B., and Eakins, J. D., “Radioactive Methods for Labelling and
Tracing Sand and Pebbles in Investigation of Littoral Drift",
International Conference on Radioisotopes in Scientific Research,
Paris, Sept. 9-21, 1957, (UNESCO/NSMIC/63), London, Pergamon
Press Ltd., 1957.

Steers, J. A., and Smith, D,. B., "Detection of Movement of Pebbles on the

Sea Floor by Radioactive Methods”, The Geographical Journal (Lond,),
Vol, 122, Pt. 3, September 1956,

CU

EXPER IMBNTAL DETERMINATION OF WAVE PRESSURE ATTENUATION
by

George W, Simmons
Research Division, Beach Erosion Board

Several attempts have been made previously to determine the relation-
ship between measured and theoretical underwater pressure fluctuations due
to surface waves, In most of these cases, controlled waves were not avail-
able and the tests were dependent on natural conditions, where the analysis
of actual surface wave action is difficult. Observations under controlled
conditions permit more accurate determination of this relation,

Theoretically, the relationship between bottom pressure fluctuations P
at depth Z during passage of a wave and wave height H is given by:

Cosh (2m doz )

lao} fac)
'

Cosh( 2 < )

where d is the depth of water from still water level to the bottom and L
is the wave length at the particular location,

Based on field data, Seiwe11! found that a correction factor of 1,35
should be applied in deriving wave heights from bottom pressure fluctua~
tions by the theoretical formula, Later laboratory investigations by the
University of California Fluid Mechanics Laboratory group indicated the
factor to be about 1.1,

Additional data on the relationship have been obtained by the uSe of
two Stratham Laboratories (Strain gage type) pressure gages in the Beach
Erosion Board's prototype tank where wave characteristics were governed.
This tank measures 635 feet long; however, its effective length for these
tests was only 490 feet because of a rubble-mound breakwater located 145
feet from the end opposite the wave generator, The pressure data were
obtained in conjunction with a study on the Stability of rubble mounds,

Measurements were made at two locations along the tank; 210 feet and
300 feet seaward of the rubble structure, Surface fluctuations at both
locations were measured by step-resistance type wave gages. In addition,
at Station 210, visual readings were made for each individual wave by
observing the highest and lowest water line seen on a fixed water stage
gage, Bottom pressure fluctuations at the same locations were obtained
by the two pressure gages. These were mounted to heavy 3=-inch iron plates
to keep the gages stable on the tank floor, All gages were calibrated
statically by raising and lowering the gage. Figure 1 shows the tank
set-up and the combination of gages and station locations to give three
individual cases of bottom-to-surface pressure fluctuation comparisons,

ED

1, 2, see references on next page.

28

Six wave periods were tested: 2.61, 3.75, 5.60, 7.87, 11.33, and
16,01 seconds, For each of these periods three wave heights, ranging
from approximately 1,1 to 3.7 feet, were investigated, Water depth varied
Slightly from 14,02 to 14,30 feet.

Analysis was limited to that portion of a run which contained unre-
flected waves, yet the waves had built up to a uniform height, This number of
eligible waves varied from 1 to 8, as determined by the tank length and the
wave period (or velocity). The theoretical limits were confirmed by the
wave records, Simultaneous recordings of each individual wave were matched
up for comparison, Figure 2 is an example of corresponding wave records,

Three identical runs were made for each condition of wave height and
period, and measurements were averaged in order to aSsure a consistency in
results, Table 1 summarizes averaged tabulations for each wave condition
by showing an average bottom-to-surface pressure fluctuation ratio for
each wave condition and for each means of comparison, Table 1 also indicates
the maximum and minimum ratio for each wave condition as found from the
analysis of each individual wave, Figure 3 presents these data in graphical
form,

A summary curve was also obtained by averaging all pressure ratios
for each wave period regardless of wave height, gage location or means of
comparison, This curve iS compared with a theoretical curve in Figure 4,

A review of the comparison curves in Figure 4 indicates that measured
ratios differ from theoretical ones only for wave periods of about 4 through
13 seconds, Correction factors for the test periods within this range are:
1,12 for 5.60 seconds, 1,17 for 7.87 seconds and 1,08 for 11.33 seconds,
giving an average of 1,12; in general agreement with that of the University of
California,

Further investigation of the experimental data revealed, in general,
that as the wave height decreased the pressure gage response increased
(particularly for the longer wave periods), This indication can be seen
in Figure 5, Apparently wave heights (or steepness) can also affect deter-
mination of the true pressure attenuation,

1 “Investigation of Underwater Pressure Records and Simultaneous Sea Surface
Pattern”, H, R. Seiwell, Woods Hole Oceanographic Institution, 1947,

2 "Sub-Surface Pressures due to Oscillatory Waves", R, G. Folsom, Transactions,
American Geophysical Union, Vo. 28, No. 6, p. 875, December 1947,

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30

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33

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OF WAVE HEIGHT

34

PROGRESS REPORTS ON RESEARCH SPONSORED BY
THE BEACH EROSION BOARD

Compiled by Thorndike Saville, Jr., ReSearch Division
Beach Erosion Board

Summaries of progress made during fiscal year 1960 (i.e. to June
30, 1960) on the several research contracts in force between universities
or other institutions and the Beach Erosion Board, together with brief
statements as to the status of some research projects being prosecuted
in the laboratory of the Beach Erosion Board, are presented below. These
summaries supplement and continue those contained in prior issues of the
Bulletin.

lie University of California, Contract DA-49-055-eng-8. Sources of
Beach Sand.

Seasonal sampling of eighteen beaches in the San Francisco area
was continued. Sampling has been extended to a series of beaches between
Russian River and the Oregon line to indicate properties of Northern
California beaches. Studies along the more northern beaches will also
permit comparison with the previous work done in the San Francisco area.
The university has obtained (under other work) an electric magnetic
separator which it plans to use to aid in the segregation of minerals of
different magnetic susceptibility in samples from these beaches. It is
hoped that analyses in this manner may aid in the tracing of sand move-
ment, and determination of source areas.

II. Massachusetts Institute of Technology, Contract DA-49-055-eng-16.
Sorting of Beach Sand by Waves.

A report "The Damping of Oscillatory Waves by Laminar Boundary
Layers" discussed in the last Annual Bulletin report, has been published
as Technical Memorandum No. 117 of the Board. The applicability of the
two previously developed equations for incipient and equilibrium sediment
motion to the prediction of the sorting of natural sands on equilibrium
beaches has been studied experimentally with a few tests on a 1 to 20
slope beach. Although results are somewhat preliminary, a degree of
correlation of sand sorting as predicted by theory was noted. A com-
prehensive report covering the last two years of work is being prepared.

III. University of California, Contract DA-49-O055-eng 17. Pundamental
Mechanics of Sand Movement by Waves.

A report "Sand Movement by Wind Action (on the Characteristics of
Sand Traps)" will be published in August 1960 as Technical Memorandum
No. 119 of the Board. This report discusses the calibration of various
types of sand traps in a wind tunnel; efficiencies of these various
types have been checked and compared with each other. As a result of

35

these tests, a trap giving an efficiency close to 100 percent has been
developed. This instrument is being tested under field conditions in

a 30 x 30-foot sand area. In addition, equipment for studying sediment
movement by wave action was revised, and calibration of the apparatus
was completed, prior to initiation of further tests.

IV. University of California, Contract DA-49-055-eng-44. Laboratory
Study of Wave Refraction.

Laboratory experiments have been made on the reflection and energy
dissipation characteristics of a solitary wave at a sloping wall at an
oblique incidence. These laboratory studies have been largely completed
and a report is in preparation. Some theoretical work has been done on
an exact second order theory for cnoidal and solitary waves. The results
appear to agree more favorably with laboratory measurements of several
wave characteristics than is the case with other theoretical results.

V. Agricultural and Mechanical College of Texas, Contracts DA-49-055-
eng-56-4 and 58-9. Estimation of Hurricane Surges.

Additional work was done on the research problem in Narragansett
Bay (eng-56-4). This work included analysis of the surge forcing
functions for the various hurricanes, which involves an analysis of the
alongshore as well as the onshore components of wind and wind stress.
A revised program for surge calculations on the computer was compiled.
This program incorporates astronomical tide with the surge by a suitable
input condition at the edge of the shelf. Numerical stability for the
bay calculations is obtained by use of a schematic made up of subchannels
with identical travel times (for a free surge), and by the incorporation
of a filter at each step to subdue any erratic behavior. The calcula-
tions also involve taking into account the variation of water storage
area within the bay as a function of water elevation, thus preventing
overestimates of the peak surge at Providence and other points near the
head of the bay where flooding of low-lying land areas occurs. Computa-
tions for observed and design conditions are under way. Computational
methods previously developed for determining storm surge estimates in
the New York Harbor entrance area (eng-58-9) have been used to make
predictions for hurricane water levels in that area. A report
summarizing this work "The Prediction of Hurricane Storm Tides in New
York Bay” will be published in August 1960 as Technical Memorandum No.
120 of the Board. This report describes the effort made to correlate
storm surges in New York Bay with the meteorological characteristics of
the storms producing them, and thus to predict the nature of the storm
surge resulting from a hypothetical design hurricane. The method used
is largely empirical, but has theoretical guidance. Therefore, though
the constants involved apply only to the specific areas studied, the
general method and procedure may well have more general application.

VI. Dr. W. C. Krumbein (Consultant). S tudy of Beach Sampling Methods.

Design of computer program to study the application of computing
machine methods to the study of factors influencing beach characteristics

36

and stability was continued. Application was made to data gathered a
number of years ago in the area of Mission Bay, California, but the
small range of data and the lack of precision inherent in some of the
data presented considerable difficulty. Results to date, however, tend
to confirm that wave height and period are important factors which
influence beach slope.

VII. Beach Erosion Board Laboratory.

(a) Wave Forces on Structures.

Analysis was continued of the wave force data obtained in the large
wave tank on a vertical 12-inch diameter pile. This work has been
pointed particularly toward the phase relationship of the water elevation,
water velocity, and wave force with the passage of the waves. A report
on this work is under preparation.

(b) Wave Run-up.

Additional large scale data involving waves up to 3-1/2 feet in
height were gathered on a 1 on 1-1/2 riprap protected slope using 160-
pound rock in an attempt to determine possible existence of a scale
effect. Final analysis of these data is awaiting calibration of the
wave tank, and accurate determination of the wave height at the structure,
with the structure not in place. The wave run-up data presented by Hudson
in his article "Laboratory Investigation of Rubble Mound Breakwaters",
published by the American Society of Civil Engineers, were re-analyzed in
terms of deep water parameters. Use of the deep water parameters provides
a constant relative depth value as a reference, thus making the data
somewhat eaSier to use. These revised curves are being published in a
discussion of this paper in the September 1960 American Society of Civil
Engineers Waterways and Harbors Division Journal.

(c) Study of Sand Bypassing Operations.

An attempt is being made to gather all available data on sand by-
passing operations (past, present, or planned) for correlation and study.
The hydrographic survey data obtained in the Port Hueneme area in June
1959 are being analyzed. A field observation program has been organized
for the vicinity of the new Ventura County Harbor at which bypassing
operations are scheduled to start in the future. This operation utilizes
an offshore breakwater (parallel to the shore) to form a protected area
which serves as a sand trap. Sand deposited in this protected area will
be dredged and typassed to the downdrift side of Port Hueneme. A general
study is under way of the applicability of using a radioactive source
type instrument with velocity meters to measure quantity of material
pumped in bypass operations.

37

(d) Laboratory Study on Relation of the Littoral Drift Rate to
Incident Waves.

A series of additional laboratory tests were made in the Shore
Processes Test Basin to obtain further data on the relation of rate of
littoral movement to incident wave characteristics. A few additional
tests were made on the 1 to 20 slope, before remodeling to a 1 to 10
slope to permit faster accumulation of data on this one Slope. Most of
this year’s tests therefore have involved the 1 to 10 slope. Tests in-
volving different lengths of beach have indicated that a beach length of
about 40 feet is sufficient, for the range of values being tested, to
eliminate any effect due to beach length. Accordingly most of the tests
made this year, and those planned for the future, will be made with these
shorter beaches; the shorter beach length enables somewhat more rapid
testing, and considerably easier handling. Most of the tests have utilized
a higher wave energy level than previously, with a maximum rate of trans-
port during this period being about 7,500 pounds (dry weight) per hour
with approximately 6-inch waves. Tests planned involve 8 to 9-inch waves,
and yet higher rates of sand movement are expected. A report discussing
the work of the previous several years was presented at the October 1959
American Society of Civil Engineers’ meeting in Washington, and this oral
report is being put into a form suitable for publication, A further
report discussing the results of the testing since that time is also in
preparation. Work has also been carried out attempting to relate measured
net quantities of littoral accumulation at several points on the east
coast to wave energy derived from statistical hindcast wave data.

(e) Measurement of Suspended Material in Laboratory Wave Tanks.

Certain additional suspended sediment samples were obtained in a
small laboratory flume and in the wave basin in conjunction with tests
on littoral movement. In addition a series of samples has been gathered
in a wave flume using lower specific gravity crushed coal rather than
sand. It is hoped that these latter measurements may aid in defining
scale relations between model and prototype measurements. For this
purpose, they will be compared with measurements of material in suspension.

(f) Wave Theory.

Work has continued on basic wave theory with particular emphasis on
the determination of design wave criteria. A report "Wave Variability and
Wave Spectra for Wind-Generated Gravity Waves" has been published as
Technical Memorandum No. 118 of the Board. A number of wave records from
a wide variety of locations were subjected to a statistical analysis and
distribution functions of wave heights and periods derived. If the wave
length is regarded as proportional to the wave period squared (as assumed
in this report) length distribution functions may also be derived. The
joint distribution relationships between length or period and the wave
heights have also been obtained. Following these distribution functions,

38

an analytical expression for the families of wave spectra has been
derived. These spectra have been compared with those proposed by others
and were found to be in good agreement with available data. In addition,
a theory for waves of finite height has been derived, and will be
presented in a paper before the Coastal Engineering Conference in August
1961. This theory is an exact one, and may be extended to any order.

It is represented by a summation in harmonic series, each term of which is
in an expanded form. The terms of the series when expanded result in an
approximation of the exact theory and this approximation is identical to
Stokes’ wave theory extended to the same order. The theory represents
irrotational-divergenceless flow.

(g) Equilibrium Profile and Model Scale Effects Studies.

Testing was continued in a small tank utilizing low specific
gravity material (crushed coal) to study the effect of scale on movable
bed models under wave action. Profiles derived from these tests bear
basic resemblances to the profiles obtained with large (up to 5-1/2 foot)
waves on a sand beach, from which the small-scale tests were modeled.
However, certain differences still occur. One possible explanation for
some of these is the wide range of specific gravities of individual coal
grains, even though the average specific gravity is modeled according to
the settling velocity of the beach sands tested.

(h) Rubble-Mound Stability.

Large-scale (7.5 to 1) tests on stability of rubble-mound structures
under wave action were continued to spot check results of the small-scale
test program at the Waterways Experiment Station. These tests involve a
1 on 1-1/2 slope rubble breakwater using approximately 1-foot diameter,
160-pound stone. Tests to determine the design wave (i.e., the height
of wave which will just initiate damage after 1-1/2 hours of wave attack)
have been completed, as have tests with damaging waves of heights
approximately 1.5 times the design height. These latter tests were run
to check the rate and amount of damage caused by waves higher than the
design wave. Final analysis of the data and interpretation of results
is awaiting precise calibration of the wave tank and determination of
wave heights at the structure location without the structure in place.
Essentially all tests made to date have involved non-breaking waves,
or waves which, if breaking, were not fully breaking. As a distinct
possibility exists that somewhat greater damage may be caused by fully
breaking waves having the same incident deep water height as non-
breaking waves, a 1 on 10 concrete beach slope is being installed in
front of the breakwater to permit generation of a fully breaking wave
on the breakwater base. Tests with this breaking wave condition will
be repeated for the same wave generator settings as were used previously
to obtain the design wave.

39

(i) Wave Measurements and Analysis.

Wave records continued to be taken at five ocean gages (Atlantic
City, New Jersey; Palm Beach and Naples, Florida; Huntington Beach and
Port Hueneme, California). Several gages have been constructed and in-
stalled in the Columbia River in connection with hydrologic studies
under way by the Walla Walla District of the Corps of Engineers for John
Day Reservoir. Additional spectrum recordings from a tape recorder have
been obtained from the wave gage at Atlantic City, and sample analyses
of these made with the spectrum analyzer are being compared with numerical
analyses made from the paper pen-and-ink recordings. Previous wave gages
of the step resistance type developed by the Board have been designed
specifically for either fresh or salt water. However, a need has arisen
in some estuaries and bays subject to fresh water flow for a gage giving
accurate measurements over a wide range of salinities. Such a gage has
now been developed at the Board, and installations are being made in
Lake Pontchartrain, Louisiana.

(j) Regional Studies.

A draft of the report on geomorphology and shore line history for
the south shore of Long Island is under review. A report on the littoral
materials of the south shore of Long Island is under preparation. Com-
pilation of geomorphological and littoral material data for the coastal
sector from Cape Henlopen to Cape Charles is under way.

(k) Technical Report No. 4, "Shore Protection Planning and Design".

A continuing study is being made to improve and supplement present
chapters of this publication. The first printing of this publication
tas been out of print for some time, and a revised edition has now been
drafted. It is planned that this revised edition will be published
some time in the spring of 1961. Major revisions or additions involve
sections on wave run-up, hurricane waves and surge, and wave forces
(including stability of rubble-mounds).

(1) Re-examination of Beach Protection Projects.

A continuing program is being carried out on the re-examination
of artificially nourished beaches to determine the effectiveness of the
fill material within the beach zones, and to better establish the factors
upon which the desired characteristics of fill material are based. Con-
tinuing studies of other projects constructed following beach erosion
control studies are under way to determine effectiveness of the various
structure components. Projects under study during this fiscal year were:
Prospect Beach, Connecticut; Asphalt Groins along New Jersey and Maryland
Coasts.

40

(m) Development of Sediment Density Probe.

A report "Development and Tests of a Radioactive Sediment Density
Probe" will be published in September 1960 as Technical Memorandum No. 121
of the Board. In this report, the development of an in-place sediment
density probe utilizing a (3-millicurie) radium source is described, as
well as its calibration by laboratory tests. Field testing in estuary,
reservoir, and bay sediments is discussed. The gage has demonstrated
satisfactory results and has the advantage of giving an indication of
densities at successive depths without withdrawing the probe.

(n) Hurricane Studies.

The staff of the Board has continued to support the hurricane study
work of the Corps of Engineers. Considerable work has been done by the
staff in developing and improving simplified methods for estimating storm
surge elevations and wave heights under a variety of shore line conditions.
Wave forces, wave run-up, and wave-overtopping phenomena connected with
seawall, dike, and barrier design under hurricane conditions have also
been studied. A generalized study of the effect of offshore slope on the
amount of wave set-up observed with high hurricane waves has been initiated.
These tests have indicated that a rough approximation of the wave set-up
at the shore line may be obtained as 1/10 the incident wave height,
although this value varies somewhat with the offshore, and particularly
the nearshore, slope. Testing in a flume has also indicated that a
submerged offshore breakwater or high bar or barrier may significantly
increase this set-up by preventing, or making more difficult, seaward
return flow along the bottom. The test results for these barriers,
however, would be expected to be considerably higher than set-up observed
in nature, as the barrier in the tests extended across the full width of
the channel and consequently alongshore escaping flow parallel to the
submerged barrier, such as would occur in nature, was prevented.

(0) Wave Pressure Attenuation with Depth.

A series of measurements using pressure gages on the bottom of the
large wave tank has been made with waves several feet in height in an
attempt to determine more accurately the attenuation of wave pressure
with depth. These tests and their results are discussed in an article
in this Bulletin.

4

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 ob-
tained 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, Summaries
of reports transmitted to Congress since the last issue of the Bulletin
and lists of completed and authorized cooperative studies follow.

SUMMARIES OF REPORTS TRANSMITTED TO CONGRESS

PEMBERTON POINT TO CAPE COD CANAL, MASSACHUSETTS

The purpose of the investigation was to determine in general the
best method of shore protection, prevention of further erosion, and
improvement of beaches, and specifically to develop plans for protec-
tion of Crescent Beach, The Glades, North Scituate Beach, Prant Rock,
and Plymouth Town Beach. The study area comprised the shores of
Massachusettes and Cape Cod Bays between Pemberton Point, about 7 miles
east of Boston, and the east end of the Cape Cod Canal, about 7 miles
southeast of Boston. It includes the shores of the towns of Hull,
Cohasset, Scituate, Marshfield, Duxbury, Plymouth and Bourne, and the
northerly tip of the town of Sandwich, a total shore frontage of about
50 miles. The shore area is extensively developed for year-round
residential use between Pemberton Point and Brant Rock, In 1950 the
permanent population of the coastal towns was about 4,000. The
summer population of these towns is about three times the permanent
population, The population of the tributary area was about 1,500,000
in 1950. The principal publicly owned sections of shore in the study
area are Nantasket Beach in Hull, Brant Rock and Green Harbor Beaches
in Marshfield, Town Beach in Plymouth and Scusset Beach in Sandwich.
All are used for recreational bathing.

The shores of the study area are fully exposed to waves of the
Atlantic Ocean, except that Cape Cod affords protection from easterly
to southerly waves, especially for the shore south of Plymouth, The
predominant direction of littoral drift is westward on shores oriented
in an east - west direction as west of Point Allerton, and generally
southward on those oriented in a north - south direction as south of
Manomet Point, On shores oriented in a northwest = southeast direc-
tion as between Point Allerton and Gurnet Point, there is little
predominance in direction df drift. Tides are semi-diurnal, the mean

42

range averaging a little more than 9 feet. The maximum tide of record
at Boston was about 5 feet above mean high water. Tides of 3 feet or
more above mean high water occur about once a year, The study area is
characterized by rocky headlands and headlands of unconsolidated glacial
material. Wave-built bars or spits have been formed. The headlands
formerly supplied material to the intervening beaches, but are now
generally eroded to bedrock or so protected that they have ceased to

be a significant source of supply of material. With their reduction
in supply, the beaches have slowly deteriorated. However, groins have
been found to be capable of causing accretion south of Manomet Point
where there is an appreciable supply of material from eréding bluffs.
Elsewhere the natural supply of material is insufficient for the forma-
tion of adequate protective beaches by groins alone. The construction
and maintenance of adequate beaches may be accomplished by artificial
placement of sand, The rate of loss of fill can be reduced by groins,
except where movement of material is principally to the offshore
bottom.

The Division Engineer and the Beach Erosion Board developed plans
for protecting and improving the shores at Crescent Beach, The Glades,
North Scituate Beach, Brant Rock and Plymouth Town Beach, and made
economic analyses of these plans, They found that projects for
protecting and improving Scituate Beach, Brant Rock and Plymouth Town
Beach are justified by prospective benefits and that public interest
involved warrants Federal aid in construction under established policy.
The Division Engineer and the Beach Erosion Board recommended that
projects be adopted by the United States authorizing Federal partici-
pation by the contributicn ef Federal funds. in amount of one-third of
the first costs of measures for the protection of those shores,
substantially in accordance with the following plans, with some
minor modifications as may be considered advisable by the Chief of
Engineers:

a. North Scituate Beach, Scituate, Widening about 2,500

feet of beach to 125-foot width by direct placement of suitable sand

fill;

b, Brant Rock, Marshfield, Widening approximately 2,700
feet of beach to a l25-foot width by direct placement of suitable

sand fill and raising the inshore end of the existing jetty to Brant
Rocks

c. Town Beach, Plymouth. Widening approximately 1,300 feet
of beach to a 125-foot width by direct placement of suitable sand fill,
construction of two groins, each about 300 feet long, and construction

of a concrete seawall approximately 165 feet long.

The Beach Erosion Board also recommended authorization of Federal aid
to periodic nourishment of the project for North Scituate Beach for a

43

period of 10 years from the year of completion of the initial beach
restoration.

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

WESSAGUSSETT BEACH, WEYMOUTH, MASSACHUSETTS

The purpose of the investigation was to determine the best method
of restoration and stabilization of the beach and stabilization of the
bluff between Wessagussett Yacht Club and the junction of River Street
and Fort Point Road in Weymouth. The Town of Weymouth is located in
Norfolk County about 10 miles southeast of Boston. Wessagussett Beach
is located on the south shore of Weymouth Fore River, a branch of the
Boston Bay estuary. The eastern section of the study area is a short
tombolo between the glacial deposits at Fort Point and Weymouth Great
Hill, The central section consists of a narrow beach fronting the
Great Hill bluff, The western section is a wider beach fronting low
land. The total length of the study area is about 0.6 mile. Weymouth
is a residential and industrial community with a presently estimated
permanent population of about 50,000. The shore of the study area is
publicly owned except at one residence adjacent to the Yacht Club and
the frontage along River Street. The Town of Weymouth is considering
acquisition of the property seaward of River Street.

The tides in the study area are semi-diurnal, The mean and
spring ranges are respectively 9.5 and 11.0 feet. The maximum tides
of record were about 15 feet above mean low water. Tides in excess
of 3.1 feet above mean high water occur about once a year, The south
shore of Weymouth Fore River is exposed to waves up to about 3 feet
high from the northeast generated in the limited fetch of Hingham Bay,
the adjacent section of Boston Bay, Beach material has been supplied
to the shore of the study area by westward littoral transport from
erosion of bluffs to the east and within the study area. Protection
of the bluffs has reduced this supoly with resultant erosion of the
beaches.

The Division Engineer and Beach Erosion Board developed plans for
restoration and stabilization of the beach and protection of the bluff,
and concluded that practicable plans for protection and improvement of
Wessagussett Beach comprise sand fills, groin and rubble-mound wall
construction. They further concluded that a project for Wessagussett
Beach is justified by prospective benefits and that the public owner-
ship and interest involved in the project warrant Federal aid in
initial construction under the provisions of Public Law 826, 8th
Congress, The Board stated that in the event the River Street shore
frontage is acquired by a public agency, Federal aid to the extent of
one-third of the first costs is warranted, but even if the River Street
section remains in private ownership, protection thereof would result
in substantial public benefits by reason of the protection of the public
road and Federal aid toward the first costs would be warranted to the
extent of one-third adjusted by the ratio of public to total benefits
for that section. The Division Engineer and Beach Erosion Board

44

recommended that a project be adopted by the United States authorizing
Federal participation by the contribution of Federal funds in amount of
one-third of the first costs of measures applicable to the publicly
owned shores (or in the event the River Street section remains ‘privately
owned, one-third of the first costs applicable to that section adjusted
by the ratio of public to total benefits for that section), for the
restoration and protection of the shores at Wessagussett Beach, Weymouth,
Massachusetts, substantially in accordance with the following plan, with
modifications thereof as may be considered advisable by the Chief of
Engineers:

a. Wessagussett Road Section. Widening approximately
1,000 feet of beach to widths of 35 to 125 feet by direct placement
of suitable sand fill, construction of one groin about 375 feet
long and appurtenant drainage facilities.

b. Regatta Road and River Street Sections. Widening
aoproximately 1,600 ‘feet of the beach to a general width of 125
feet by direct placement of suitable sand fill, construction of
one groin about 350 feet long and two rubble-mound walls each
about 500 feet long.

The Chief of Engineers concurred in the views and recommendations
of the Beach Erosion Board,

NEWPORT BAY TO SAN MATEO CREEK, ORANGE COUNTY, CALI*ORNIA

The purposes of the investization were to determine the causes and
most effective and economical methods of controlling erosion of the shore,
Orange County is in Southern California immediately south of Los Angeles
County. Its Pacific Ocean shore line, extending in a general northwest-
southeast direction, is about 2 miles long, the portion of which is
covered by this report being about 25 miles long from Newport Bay to the
San Diego County line near the mouth of San Mateo Creek. The coastal
area from Newport Bay to San Juan Creek consists generally of a series
of pocket beaches backed by high bluffs. From San Juan Creek to San
Mateo Creek it consists of a continuous beach backed by high steep
bluffs. The principal shore communities in the study area are Laguna
Beach and San Clemente, but the population of Orange County and other
communities within 50 miles of Orange County beaches is over 1,000,900.
Two State parks with a total shore frontage of 14,500 feet are located
in the study area, Doheny Beach State Park at the mouth of San Juan
Creek and San Clemente Beach State Park in San Clemente. The tides in
the study area have a diurnal inequality, the mean and diurnal ranges
being respectively about 3.7 and 5.3 feet. The maximum tide each year
is about 7 feet above mean lower low water. Characteristic waves are

45

swells generated in distant ocean areas, They have heights up to 10
feet and periods up to 20 seconds with the greater heights and shorter
periods occurring in the winter. Winter waves generally approach the
shore from upcoast of normal, summer waves frequently approach from
downcoast of normal, As a result the predominant direction of littoral
transport is toward the southeast. Sand is supplied to the shore by
tributary streams, especially during storm runoff. The principal
contributor affecting the shore of the study area is San Juan Creek.
The volume supplied depends on occurence of floods, but is estimated
to average about 78,000 cubic yards annually. The average annual
volume of material removed from the shore in the vicinity of San Juan
Creek by littoral processes is estimated at 101,000 cubic yards, the
estimated deficiency in supply thus being 23,000 cubic yards annually.

The District Engineer developed plans for protecting the shore of
the problem areas, He and the Division Engineer and the Beach Erosion
Board concluded that the most suitable and economical plans of shore
protection for the several problem areas are as follows:

ae For Doheny Beach State Park, a protective beach 100 feet
wide and approximately 6,000 feet long by artificial placement of about
329,000 cubic yards of suitable smd on the beach, one groin 250 feet
long on the west side of San Juan Creek, maintenance thereafter to be
by periodic artificial placement of an estimated average annual quantity
of 23,000 cubic yards of sand.

b. For Capistrano Beach Colony shore, a protective beach
100 feet wide and 3,00 feet long by artificial placement of approximately
115,000 cubic yards of suitable sand,

c. For the upper San Clemente segment, a protective beach
100 feet wide and about 7,100 feet long by articicial placement of
approximately 33,000 cubic yards of sand,

They made an economic analysis of the plan of protection for Doheny
Beach State Park since the shore of this area is publicly owned, and
concluded that the plans are justified by prospective benefits and that
the public interest involved in protection of public property warrants
Federal assistance in accordance with existing policy, They further
concluded that artificial placement of suitable sand fill is the most
suitable and economical plan of protection for the shores of the
Capistrano Beach Colony and upper San Clemente segments, but that no
public interest is invclved in protection of those privately owned
shores. They accordingly recommended that a project be adopted by the
United States authorizing Federal participation by the contribution

of Federal funds in amount of one-third of the first costs of a plan
comprising a beach fill and one groin for the restoration and protection
of the shore at Doheny Beach State Park, Orange County, California, and
one=third of the costs of periodic nourishment for a period of 10 years
from the year of completion of the initial fill, with such modifications
thereof as may be considered advisable by the Chief of Engineers,

The Chief of Engineers concurred in the views and recommendations
of the Beach Erosion Board,

46

PRESQUE ISLE PENINSULA, ERIE, PENNSYLVANIA

The purposes of this cooperative study were to determine the rates
of loss and movement of the sand fill, to estimate the nourishment
requirements of the existing cooperative shore protection project which
was constructed in 1955=56, and to determine its eligibility for Federal
participation in the cost of periodic beach nourishment in accordance
with provisions of Public Law 826, 8th Congress, approved July 28, 1956,
(or subsequent to authorization of the existing project).

Presque Isle Peninsula is located on the south shore of. Lake Erie
at Erie, Pennsylvania, about 78 miles southwest of Buffalo, New York and
102 miles noutheast of Cleveland, Ohio. The peninsula is a compound
recurved sandspit projecting a maximum distance of about 2.5 miles from
an otherwise straight mainland shore. From its root to its distal end,
it has a lake shore line over 6 miles in length, The large bay between
the peninsula and thé mainland provides a spacious harbor which has been
improved by the Federal Government under the navigation project for Erie
Harbor. The peninsula provides valuable protection to the harbor.
Presque Isle Peninsula is generally low in elevation except for beach
ridges or dunes which rise to an average elevation of 20 feet above
Lake Erie low water datum, The peninsula ranges in width from about
800 feet near its root or neck to a maximum of about 1-1/) miles toward
the distal end. This includes the sand fill made on the lakeward side
in 1955-56 to restore the beach and a highway fill on the bay side made
shortly thereafter by the Commonwealth of Pennsylvania. Presque Isle
State Park, comprising about 3,200 acres, occupies practically the
entire peninsula. The State has provided adequate access roads, but
has left the area for the most part in its natural condition. The park
is a popular area for bathing, boating, fishing, and other outdoor
forms of recreation. Its large attendance, totaling over 2,850,000
persons annually, is drawn mostly from western New York, Pennsylvania,
and eastern Ohio. The public has free and unrestricted access to the
park. The Erie City Water Works and U. S. Coast Guard also have
installations on the peninsula.

The lake shore of the peninsula is exposed to wave attack from
the southwest through north to northeast. The greater frequency and
severity of storms from the westerly quadrant and the greater fetch
in that direction cause a predominant eastward movement of littoral
drift, During the period of record the supoly of beach material from
bluffs and streams west of the spit has been insufficient to replace
material eroded from the neck of the spit. Recession of the shore
line has been greatest at the root of the peninsula, gradually decreasing
to a nodal point about two-thirds of the length of the peninsula from the
root, from which point accretion has occurred as the eroded material was
deposited in that area, On several occasions the narrow neck of the
peninsula was breached by storm wave action. The earlier breaches
were closed by natural processes, The Federal Government closed a breach
in 1920-1922 and since has built seawalls and bulkheads on the lake shore
of the neck to preserve it and thus prevent the loss of protection it
affords to Erie Harbor, After this vortion of the shore was protected,
increased erosion occurred to more northeasterly portions of the peninsula,

47

Successive northeasterly extensions of protective bulkheads and groins
were made by the State until such measures passed the former nodal point,
The most northerly sections of bulkhead were generally ineffective.
Recession continued, and the highway in that area was destroyed in 196,
The cooperative project authorized by the River and Harbor Act of 195)
provided for artificial placement of sand fill, and construction of a
seawall, bulkhead, and a groin system along the neck portion of the
peninsula, The project was constructed in 1955=1956 generally in
accordance with the recommended plan, During the two years immediately
after completion of the project, the wind pattern, wave action, and ice
conditions have been quite similar to the normal long-range pattern for
a preceding 29-year period. Lake levels during the ice-free period of
1957 were almost identical with the 99-year mean levels for the same
months, and during 1958 the level was 0.9 foot below the long-term mean
level, Survey data obtained in the falls of 1956, 1957 and 1958 were
used for estimating the rate of loss of the material from within the
limits of the original beach fill and for prediction of future
replenishment requirements, A comparison of these data indicates an
amual loss of about 15,000 cubic yards from within the original

beach fill limits.

The District Engineer determined the rates of loss and movement of
the sand fill, and developed a periodic nourishment plan for maintaining
a suitable protective and recreational beach, He concluded, and the
Division Engineer and Beach Erosion Board concurred, that placement
of a maximum of approximately 15,000 cubic yards of sand will be
required annually. The District and Division Engineers and the Beach
Erosion Board found that the project for protection and improvement of
Presque Isle Peninsula is amply justified by prospective benefits.

The Board stated that the State has made many improvements in park
facilities since completion of the beach fill and that these improve-
ments increase the benefits from shore protection and enhance the use

of the recreational beaches, The Board also concurred in the view

that periodic nourishment is the most suitable and economical measure

for stabilizing the shores of the veninsula and is thus eligible for
Federal aid in accordance with the provisions of Publie Law 826, 8th
Congress. Accordingly the Beach Erosion Board recommended modification
of the existing Federal project for Presque Isle Peninsula to. authorize
Federal participation by the contribution of Federal funds in the amount
of one-third of the costs of periodic nourishment of the shore for a
period of 10 years from the year of the first major nourishment operation,
all generally in accordance with the plan of the District Engineer with
such modifications thereof as in the discretion of the Chief of Engineers
may be advisable,

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

48

NORTH SHORE OF CAPE COD FROM CAPE COD CANAL TO PROVINCETOWN, MASSACHUSETTS

The purpose of the investigation was to determine the best methods of
stabilization and protection and to develop detailed plans for protection
of certain limited shore areas, The study area comprised the shore of Cape
Cod Bay between the east end of the Cape Cod Canal, about 50 miles southeast
of Boston, and Race Point, Provincetown. It included the shores of the Towns
of Sandwich, Barnstable, Yarmouth, Dennis, Brewster, Orleans, Eastham,
Wellfleet, Truro and Provincetown, a total shore frontage of about 70 miles.
The shore area is developed principally for summer use. In 1955 the perma-
nent population of the coastal towns was about 31,000. The summer population
of these towns is about three times the permanent population. The principal
publicly owned sections of shore are located in Dennis, Brewster, Orleans,
Eastham, Wellfleet and Truro, The shores of the westerly part of the study
area are fully exposed to waves of the Atlantic Ocean approaching from the
north and northeast across Cape Cod Bay, The predominant direction of
littoral drift in this section is eastward. The east shore of the study
area is exposed to waves from the northwest to southwest generated in Cape
Cod Bay. The predominant direction of littoral drift on this shore is
northward, except on Provincetown Beach where, due to the orientation of
this beach, it is toward the southeast. Tides are semi-diurnal, the mean
ranges being 8.7 feet at the Cape Cod Canal entrance and 10.1 feet at
Wellfleet Harbor, The maximum tide of record at Boston was about 5 feet
above mean high water, with tides of 3 feet or more above mean high water
occurring about once a year, The study area is characterized by bluffs of
unconsolidated glacial material which supply material to the beaches. Groins
have been found to be capable of causing accretion in areas where there is an
appreciable supply of material from eroding bluffs, Elsewhere the natural
supply of material is insufficient for the formation of adequate protective
beaches by groins alone, The building and maintenance of adequate beaches
may be accomplished by artificial placement of sand. The rate of loss of fill
can be reduced by groins, except where movement of material is principally to
the offshore bottom.

The Division Engineer and the Beach Erosion Board developed plans for
protecting and improving the shores of the area, and made economic alalyses
of proposed protective and improvement measures for shores eligible for
Federal aid in protection, They found that practicable plans which merit
consideration for the protection and improvement of shores within the
study area are as follows:

ae Town Neck Beach: Widening about 6,500 feet of beach to a
125-foot width by direct placement of suitable sand fill and raising the
inshore end of the existing Cape Cod Canal jetty.

b. Spring Hill Beach: Widening about 1,000 feet of beach to a
125-foot width by placement of suitable sand fill in a stock pile at the
westerly end of the beach.

c. Brewster Bluffs: Widening about 5,000 feet of beach to a
125-foot width by direct placement of suitable sand fill.

49

d, Eastham Beaches: Widening about 9,500 feet of beach to a
125-foot width by direct placement of suitable sand fill and construction
of nine groins generally about 300 feet long, the placement of sand fill
to be deferred until it is ascertained if groins fill naturally at a
reasonable rate.

e. Indian Neck: Construction of one groin about 150 feet long.

f, Pilgrim Beach: Widening about 8,000 feet of beach to a 125~
foot width by construction of eight stone groins generally about 280 feet
long.

ge Provincetown Beach: Widening about 1,600 feet of beach to a
125-foot width by direct placement of suitable sand fill, construction of
four stone groins generally about 30 to 380 feet long and construction of
a concrete seawall about 1,200 feet long, the placement of sand fill to be
deferred until it is ascertained if groins fill naturally at a reasonable
rate.

The Division Engineer and the Beach Erosion Board concluded that projects
for Town Neck, Thumpertown and Provincetown Beaches are justified by
prospective benefits and that the public ownership and interest involved

in the projects warrant Federal aid in initial construction under established
policy. The Board stated that in the case of Town Neck Beach, periodic
nourishment is the most suitable and economical remedial measure and may
therefore be eonsidered construction eligible for Federal aid. Accordingly
they recommended that vrojects be adopted by the United States authorizing
Federal participation by the contribution of Federal funds toward the costs
of measures for the »rotection of the shores at Town Neck Beach, Thumpertown
Beach and Provincetown Beach, Massachusetts, substantially in accordance
with the following plans with such modifications thereof as may be
considered advisable by the Chief of Engineers:

a. Town Neck Beach, Sandwich: Widening approximately 6,500 feet
of beach to a 125-foot width by direct placement of suitable sand fill and
raising the inshore end of the existing east jetty of Cape Cod Canal.

b. Thumpertown Beach, Eastham. Widening approximately 1,500
feet of the beach to a 125-foot width by direct placement of suitable
sand fill and construction of one groin about 300 feet long.

c. Provincetown Beach, Provincetown, Widening approximately
1,600 feet of beach to a 125-foot width by direct placement of suitable
sand fill, construction of four groins and about 1,200 feet of concrete
seawall, the placement of sand fill to be deferred until it is ascertained
that the groins will not fill naturally to provide a satisfactory protective
beach.

The recommended Federal contribution toward the projects would be the
entire cost of raising the Federal jetty for Town Neck Beach and one-third

50

of the remaining first costs of the three projects. In addition Federal

aid of one-third of the costs of periodic nourishment for an initial period
of ten years from the year of completion of the initial work was recommended
for Town Neck Beach,

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

SOUTH SHORE OF LONG ISLAND FROM FIRE ISLAND INLET TO MONTAUK POINT, NEW YORK

The purpose of the investigation was to determine the most practicable
and economical method of restoring adequate recreational and protective
beaches and providing continued stability to the shore. In addition to a
single-purpose shore protection plan developed under the foregoing authority,
the report submitted by the District and Division Engineers included study of
the needs and methods for protection against damages caused by hurricanes
under the provisions of Public Law 71, 8th Congress, resulting in a dual-
purpose plan which would provide both hurricane and shore protection. In
its review of the report the Beach Erosion Board gave consideration to the
technical adequacy of both plans but limited its consideration of project
justification and Federal participation to the single=purpose shore protection
plan in accordance with its statutory functions as prescribed in section
3 of Public Law 166, 79th Congress.

The study area, lying entirely in Suffolk County, comprised the
83=-mile length of shore on the south coast of Long Island between Fire
Island Inlet and Montauk Point. The western end of that area is about
50 miles by water south and east of New York City, This shore is an
important summer recreational area with development ranging from colonies
of small bungalows to villages of large summer homes, Suffolk County had
a permanent population of over 528,000, with over 368,000 living in towns
adjacent to the study area, according to 1957 estimates. The summer
population is incréased by thousands of vacationists, At the time of
reporting about 18.) percent of the shore in the study area was publicly
owned, The principal publicly owned sections were Fire Island and Hither
Hills State Parks, and Smith Point Park owned by Suffolk County. Additional
shore areas on each side of Moriches and Shinnecock Inlets are being
acquired by Suffolk County for park purposes but were not included as
publicly owned shore in the present report for computations of the extent
of Federal assistance in proposed protective measures, The coastal area
under study is divided into two distinct natural sections. The westerly
SO0=mile section consists of barrier beach islands generally less than
1/2 mile in width, The easterly 33-mile section of the shore consists of
the mainland of Long Island, the 10=mile reach west from Montauk Point
being characterized by headlands of glacial deposits, The shore of the
study area is exposed to waves of the Atlantic Ocean. To the east and
southeast the fetch is unlimited, but to the west and southwest the fetch
is limited by the shore of New Jersey. The predominance of energy
components is thus such as to produce a dominant westward littoral
transport of beach material, The estimated annual rate of littoral transport
at Fire Island Inlet is 50,000 cubic yards. The importance of reversals

5

in direction of transport is somewhat greater in the eastern than in the
western part of the study area, with a corresponding decrease in the net
rate of westward littoral transport in the former, The ocean mean tidal
range increases from 2.0 feet at Montauk Point to h.1 feet at Fire Island
Inlet. The highest ocean level of record, about 10 feet above mean sea
level, occurred during hurricanes in 1938 and 1954. Moriches-and Shinnecock
Inlets were both opened by natural forces during storms, the former in
1931 and the latter in 1938. Moriches Inlet migrated westward and closed
in 1951. Local interests constructed stone jetties on both sides of
Moriches Inlet and performed dredging on the bayward side in 1952-53, The
inlet reopened during a storm in 1953 while this work was in progress. In
1952-5); local interests also constructed stone jetties on both sides of
Shinnecock Inlet. Satisfactory stabilization of the inlets was not accom=
plished as a result of these measures, Both inlets are the subject of a
recent Federal study as a result of which improvements thereof for
navigation were recommended, Included in the recommendations were
provisions for transferring the littoral drift westward across Moriches
and Shinnecock Inlets.

The District Engineer concluded that the most practical plan of
protection consists of a dual-purpose plan for widening of the beach
along the developed areas between Kismet and Mecox Bay to a minimum
width of 100 feet at an elevation of 1) feet above mean sea level,
raising of dunes to an elevation of 20 feet above mean sea level from
Fire Island Inlet to Hither Hills State Park, at Montauk and opposite
Lake Montauk Harbor, supplemented by grass planting on the dunes,
interior drainage structures at Mecox Bay, Sagaponack Lake and Georgica
Pond, and possible groin construction if experience indicated the need
fherefor, An alternative plan was developed for shore protection alone.
It consists of placing beach fill where required to vrovide a berm 100
feet wide at an elevation of 10 feet above mean sea level from Kismet
to Bridgehampton and deferred construction of groins, Maintenance of
the stability of the shore would be accomplished by periodic replenish=
ment of sand losses under either plan. The District and Division
Engineers made economic analyses of the foregoing plans of shore and
hurricane protection and concluded that the dual-purpose plan of
protection is amply justified by evaluated benefits, They found that
public benefits justify Federal aid to first and periodic nourishment
costs for shore protection projects in the Flood Control Act of 1958
(Public Law 85-500, 85th Congress), Accordingly they recommended
adoption of a dual-purpose project by the United States, the United
States paying 51 percent of the first costs thereof and 4.3 percent
of the annual costs for periodic nourishment for a period of 10 years.

The Beach Erosion Board concurred with the reporting officers in
the view that the combined improvement is a technically practicable
plan for the area and will provide the degree of protection contem-
plated, Accordingly, subject to determination by the Chief of Engi-
neers, after review by the Board of Engineers for Rivers and Harbors,
that the dual-purpose plan is suitable and economically justified, the
Board recommended adoption of the improvement, essentially as proposed

52

by the District and Division Engineers subject to the conditions that
the construction of the groins be deferred pending demonstration of
their necessity, and that local interests meet certain requirements
of local cooperation.

The Board of Engineers for Rivers and Harbors and the Chief of
Engineers concurred in the conclusions and recommendations of the
Beach Erosion Board,

53

COMPLETED COOPERATIVE BREACH EROSION STUDIES

BEB FEDERAL PROJECTS
REPORT PUBLISHED IN RECOMMEN- AUTHORIZED
LOCATION COMPLETED H. DOC. CONG. DATION BY CONGRESS
ALABAMA
Perdido Pass (Alabama Pt.) 18 Jun 5) = 27h 8h Unfav.
CALIFORNIA
Santa Barbara - Initial 15 Jan 38 552 vi Unfav.
Suppl. 18 Feb )2
Final 22 May 7 39761 80 Unfav.
Ballona Creek & San Gabriel
R. (Partial) 11 May 38 Unfav.
Orange County 10 Jan hO 637 76 Unfav.
Coronado Beach h Apr 1 636 rae Unfav.
Long Beach 3 Apr h2 Unfav.
Mission Beach h Nov h2 Unfav.
Pt. Mugu to San Pedro BW Oop afore) Sal eae? 83 Fave 3 Sep 5h
Carpinteria to Pt. Mugu h Oct 51 29 83 Fav. 3 Sep 5h
Oceanside, Ocean Beach,

Imperial Beach & Coronado,

San Diego County 26 Jul 55 = 399 8h Fave 3 Jul 58
Santa Cruz County 13 Sep 56 179 85 Fave 3 Jul 58
Humboldt Bay (Buhne Pt.) 29 Mar 57 282 85 Fave 3 Jul 58
Newport Bay to San Mateo

Creek, Orange County 3 Dec 59 398 86 Fav. 14 Jul 60
San Diego County 30 Jun 60 456 86 Fave

CONNECTICUT
Compo Beach, Westport 18 Apr 35 239 7h Unfav.
Hawk's Nest Beach, Old Lyme 21 Jun 39 Unfav,.
Ash Crk. to Saugatuck R. 29 Apr 9 = Sh 81 ~—s Fav. 17 May 50
Hammonasset R. to East R. 29 Apr ho = h7hy Si) rave 3 Sep 5h
New Haven Hbr. to

Housatonic R, 29 Jun 51 203 83 Fav. 3 Sep 5k

Conn. R. to Hammonasset R, 28 Dec 51 51h 82 Unfav.

Pawcatuck R. to Thames R,. 31 Mar 52 31 83 Unfav.

Niantic Bay to Com. R,. 11 Jul 52 Bh 83 Unfav. 3 Sep 5h
Housatonic R. to Ash Creek 12 Mar 53-28 83 Fav.

East R, to New Haven Hbr, 15 Nov 55 395 8h Fav. 3 Jul 58
Saugatuck R. to Byram R. 1; Nov 56 17h 85 Fave 3 Jul 58
Thames R. to Niantic Bay 17 Jun 57 «33h 85 Unfav.

54

REPORT
LOCATION COMPLET ED
DELAWARE

Kitts Hummock to Fenwick Is. 11 Feb 57

FLORIDA
Blind Pass (Boca Ciega) 1 Feb 37
Miami Beach 1 Feb 37
Hollywood Beach 28 Apr 37
Daytona Beach 15 Mar 38
Bakers Haulover Inlet 21 May 45
Anna Maria & Longboat Keys 12 Feb 47
Jupiter Island 13 Feb 47
Palm Beach(1) 13 Feb 47
Pinellas County 22 Apr 53

Palm Beach County (Lk. Worth
Inlet to S. Lake Worth I.) 12 Jul 57
Key West 10 Mar 58

GEORGIA

St. Simon Island 18 Mar 40

HAWATI

Waikiki Beach 5 Aug 52
Waimea & Hanapepe Bay, Kauai 17 Jan 56

ILLINOIS

State of Illinois 8 Jun 50

PUBLISHED IN

H. DO.

216

187
169
253
571
527
760
765
772
380

342
413

820

227
432

28

CONG.

76

83
84

83

FEDERAL PROJECTS

RECOMMEN=- AUTHORIZED
DAT ION BY CONGRESS

Fav. 3 Jul 58
Unfav.

Unfav.

Unfav.

Unfav.

Unfav.

Unfav.

Unfav.

Fav. 17 May 50
Fav. 3 Sep 54
Fav. 3) Jul 53
Fav. 14 Jul 60
Unfav.

Fav. 3 Sep 54
Fav. 3 Jul 58
Fav. 3 Sep 54

(1), 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 1940. Final report on experimental groins was published in
1948 as Technical Memo. No. 10 of the Beach Erosion Board.

55

LOCATION

Grand Isle
Grand Isle

Old Orchard Beach
Saco

South Shore of Cape Cod
(Pt. Gammon to Chatham)

Salisbury Beach

Winthrop Beach

Lynn-Nahant Beach

Revere Beach

Nantasket Beach

Quincy Shore

Plum Island

Chatham

Pemberton Pt. to Cape Cod
Canal

Wessagussstt Beach,
Weymouth

Cape Cod Canal to
Provincetown

Berrien County (St. Joseph)

Hancock County
Harrison County - Initial
Harrison County - Suppl.

BEB
REPORT

LOUISIANA

28 Jul 36
28 Jun 54

MAINE

20 Sep 35
2 Mar 56

26 Aug 41
26 Aug 41
12 Sep 47
20 Jan 50
12 Jan 50
12 Jan 50
2 May 50
18 Nov 52
22 Oct 56

13 Jan 59
6 Jul 59
5 Feb 60
MICHIGAN

17 Jun 57

MISSISSIPPI

3 Apr 42
15 Mar 44
16 Feb 48

56

92
132

32

MASSACHUSETTS

764
134
146
145
243
167
272
334

404

336

682

PUBLISHED IN
COMPLETED H. DO.

CONG.

75
84

85

85

80

FEDERAL PROJECTS
RECOMMEN= AUTHORIZED

DATION BY CONGRESS
Unfav.

Unfav.

Unfav.

Unfav.

Unfav.

Unfav.

Fav. 17 May 50
Fav. 3 Sep 54
Fav. 3 Sep 54
Unfav.

Fav. 3 Sep 54
Unfav.

Unfav.

Fav. 14 Jul 60
Fav. 14 Jul 60
Fav. 14 Jul 60
Fav. 3 Jul 58
Unfav.

Fav. 30 Jun 48

BEB FEDERAL PRO S

REPORT PUBLISHED IN RECOMMEN= AUTHORIZED
LOCATION COMPLETED H. DOC. CONG. DATION BY CONGRESS

NEW HAMPSHIRE

Hampton Beach 15 Jul 32 Unfav.
Hampton Beach 14 Sep 53 325 83 Fav. 3 Sep 54
NEW_ JERSEY
Manasquan Inlet & Adjacent
Beaches 15 May 36 71 75 Unfav.
Atlantic City 11 Jul 49 538 81 Fav. 3 Sep 54
Ocean City 15 Apr 52 184 83 Fav. 3 Sep 54
Sandy Hook to Barnegat Inlet 24 Mar 54 361 84 Fav.
Review Report = Sandy Hook
to Barnegat Inlet 6 May 57 332 85 Fav. 3 Jul 58

Barnegat Inlet to Delaware

Bay Entrance to Cape May

Canal 22 Sep 58 208 86 Fav. 14 Jul 60
Delaware Bay,Shore =

Cape May Canal to

Maurice River 10 Jun 60 Unfav.
NEW YORK

Jacob Riis Park, Long Island 16 Dec 35 397 74 Unfav.
Orchard Beach, Pelham Bay,

Bronx 30 Aug 37 450 75 Unfav.
Niagara County 27 Jun 42 271 78 Unfav.
South Shore of Long Island 6 Aug 46 Unfav.
Selkirk Shores State Park 21 Oct 53 343 83 Fav. 3 Sep 54
Fair Haven Beach State Park 18 Jun 54 134 84 Fav. 3 Jul 58
Hamlin Beach State Park 20 Sep 54 138 84 Fav. 3 jul 58
Braddock Bay State Park 15 Apr 55 Unfav.
Fire Island Inlet to

Jones Inlet 10 Feb 56 411 84 Fav. 3 Jul 58

Fire Island Inlet to Montauk
Pt. (combined coop. BEC &
Hurr.) 30 Jun 59 425 86 Fav. 14 Jul 60

NORTH CAROLINA

Fort Fisher 10 Nov 31 204 72 Unfav.
Wrightsville Beach 2 Jan 34 218 73 Unfav.
Kitty Hawk, Nags Head &

Oregon Inlet 1 Mar 35 155 74 Unfav.
State of North Carolina 22 May 47 763 80 Unfav.

57

LOCAT ION

Erie County - Vic. of Huron
Michigan Line to Marblehead
Cities of Cleveland &
Lakewood
Chagrin River to Fairport
Vermilion to Sheffield
Lake Village
Fairport to Ashtabula
Ashtabula to Penna.St.Line
Sandusky to Vermilion
Sandusky Bay
Sheffield Lake V. to
Rocky R.
Euclid to Chagrin River
Michigan Line to Marblehead
(Review)

PENNSYLVANIA

Presque Isle Peninsula, Erie
(Interim)
(Final)
(Review)

Punta Las Marias, San Juan

South Shore
(Towns of Narragansett,
South Kingstown, Charles-=
town & Westerly)

South Kingstown & Westerly

BEB
REPORT

COMPLETED H. DO.

OHIO

26 Aug
30 Oct

22 Mar
22 Nov

24 Jul
1 Aug
1 Aug
7 Jul

31 Oct

31 Oct
25 Jun
14 Jun

41
44

48
49

3 Apr 42

23 Apr
21 Jan

52
60

PUERTO RICO

5 Aug 47

220
a

502
596

229
Sey
350

32
126

127,
324

231
397

769

RHODE ISLAND

4 Dec 48

27 Jan

58

490
30

SOUIH CAROLINA

Folly Beach
Pawleys Is., Edisto Beach
& Hunting Island

31 Jan 35

24 Jul 51

58

156

PUBLISHED IN

CONG.

ug
79

81
81

83
82
82
83
83

83
83

83
86

80

81
86

74

FEDERAL PROJECTS
RECOMMEN- AUTHORIZED

DATION

Unfav.
Unfav.

Fav.
Unfav.

Fav.

Unfav.
Unfav.
Unfav.
Unfav.

Unfav.

Unfav.
Fav.

Fav.
Fav.

Unfav.

Fav.
Fav.

Unfav.

Unfav.

BY CONGRESS

3 Sep 54

3 Sep 54

3 Sep 54
14 Jul 60

3 Sep 54
14 Jul 60

BEB FEDERAL PROJECTS

REPORT PUBLISHED IN RECOMMEN=- AUTHORIZED
‘LOCATION COMPLETED H. DOC. CONG. DATION BY CONGRESS
TEXAS
Galveston (Gulf Shore) 10 May 34 400 73 Unfav.
Galveston Bay, Harris County 31 Jul 34 74 74 Unfav.
Galveston (Gulf Shore) 5 Feb 53 218 83 Unfav.
Galveston (Bay Shore) 19 Jun 53 346 83 Unfav.
Bolivar Peninsula (Gulf
Shore & Rollover Fish Pass) 8 Jun 59 286 86 Unfav.
VIRGINIA
Willoughby Spit, Norfolk 20 Nov 37 482 75 Unfav.
Colonial Beach, Potomac R. 24 Jan 49 333 81 Fav. 17 May 50
Virginia Beach 25 Jun 52 186 83 Fav. 3 Sep 54
WISCONSIN
Milwaukee County 21 May 45 526 79 Unfav.
Racine County 5 Mar 52 88 83 Unfav.
Kenosha 16 Sep 54 273 84 Unfav.
Manitowoc. County 15 Apr 55 348 84 Fav. 3 july 53

59

CURRENTLY AUTHORIZED COOPERATIVE BEACH EROSION STUDIES
CALIFORNIA

STATE OF CALIFORNIA. Cooperating Agency: Department of Water Resources,
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 studies cover the Orange County Shore north
of Newport Bay Harbor, Pt. Delgada to Pt. Ano Nuevo, and
a review for the entire area from Point Conception to the
Mexican Boundary.

FLORIDA

PAIM BEACH COUNTY. Cooperating Agency: Board of County Commissioners,
Palm Beach County.

Problem: To develop the most economical means of restoring the
beaches along the Atlantic Ocean shore of Palm Beach
County to a satisfactory condition and protecting the
restored beaches and shore property from future erosion.
The current study covers the area north of Lake Worth
Inlet and South of South Lake Worth Inlet,

FERNANDINA BEACH (AMELIA IS.). Cooperating Agency: City of Fernandina
Beach,

Problem: To determine the best method for restoring and retaining
an adequate beach for recreation and protection of
oceanfront properties and improvements.

VIRGINIA AND BISCAYNE KEYS. Cooperating Agency: City of Miami.

Problem: To determine the best method of preventing further
erosion and maintaining such sand as now exists along
the City and County-owned frontages on the easterly
side of Virginia and Biscayne Keys.

BROWARD COUNTY. Cooperating Agency: Board of County Commissioners,
Broward County.

Problem: To determine the best method of restoring eroded reaches
of beach, and of maintaining the restored reaches and
such other reaches as are now in good condition.

BAKER'S HAULOVER AND VICINITY. Cooperating Agency: Office of the
County Manager, Dade County.

Problem: To review the report of the 195 cooperative study of
Baker's Hanlover Inlet (H. Doc. 527/79/2) and in light
of additional data and new conditions determine what
modifications in recommendations are appropriate insofar as
beach stabilization and Federal participation are concerned,

60

HAWAII

WAIKIKI BEACH. Cooperating Agency: Department of Public Works, State
of Hawaii.

Problem: To restudy the problem at Waikiki Beach (previously
studied and reported on in H. Doc. 227/83/1) and determine
the best method of preserving and maintaining the beach
and counteracting the eroding effects of waves and littoral
drift, effectiveness of the completed portions of the exist-
ing project, and what modifications, if any, are desirable.

HALEIWA BEACH. Cooperating Agency: Board of Harbor Commissioners,
State of Hawaii.

Problem: To determine the best method of preserving or restoring
and maintaining the beach and counteracting the eroding
effects of waves and littoral currents.

ILLINOIS

EVANSTON, Cooperating Agency: Office of the City Manager, City of
Evanston.

Problems: To determine the best method of restoring and improving
the beaches at South Boulevard and Grosse Point (Light-
house) Park to provide public bathing beaches and to
protect the upland property against erosion.

LOUISIANA

BELLE PASS TO RACCOON POINT. Cooperating Agency: Department of Public
Works, State of Louisiana.

Problem: To determine the best methods of stabilization and
future protection of the Gulf shore along the section
of the southeastern Louisiana coast between Belle Pass
and Raccoon Point, including the chain of islands,
East Timbalier, Timbalier, Wine and Isles Derniere.

MAINE
HILLS BEACH, BIDDEFORD. Cooperating Agency: City of Biddeford.
Problem: To determine the best method of restoration of pro-

tective and recreational beaches and protection of
shore property.

6l

MASSACHUSETTS
NEW BEDFORD. Cooperating Agency: City of New Bedford.

Problem: To determine the best method of restoring and stabil-
izing the public beaches to protect the boulevard and
provide public bathing area.

FALMOUTH. Cooperating Agency: Division of Waterways, Massachusetts
Department of Public Works.

Problem: To determine the best method of restoring and stabiliz-
ing beaches and stabilizing bluff areas along the shore
of the town between Nobska Point and the east town line.

ROCKPORT. Cooperating Agency: Division of Waterways, Massachusetts
Department of Public Works.

Problem: To determine the best method of restoring the beach
and protecting the beach and cottage development.

SALISBURY BEACH. Cooperating Agency: Division of Waterways,
Massachusetts Department of Public Works,

Problem: To determine the best method of restoring and protecting
the beach and protecting the beach development.

NEW HAMPSHIRE

ATLANTIC OCEAN SHORE, Cooperating Agency: New Hampshire Department
of Public Works and Highways.

Problem: To develop plans for stabilization and restoration of
adequate recreational and protective beaches and for
protection of bluffs or headlands, and to determine
amount of Federal participation warranted for nourish-
ment of beach fill under the authorized Federal project
at Hampton Beach.

NEW JERSEY

STATE OF NEW JERSEY. Cooperating Agency: Department of Conservation
and Economic Development,

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
protection, Current studies cover the share from
South Amboy to Shrewsbury River in Raritan and
Sandy Hook Bays,

62

NEW JERSEY (Continued)

ATLANTIC CITY. Cooperating Agency: City of Atlantic City.

Problem: To determine the effect of Public Law 826, 8th Congress
on the existing authorized project for beach erosion
control,

NEW YORK

ATLANTIC COAST OF LONG ISLAND BETWEEN JON&S INLET AND NORTON POINT,
AND STATEN ISLAND, Cooperating Agency: Long Island State
Park Commission.

Problem: To determine the best method of restoring adequate
recreational and protective beaches and providing
continued stability to the shores of Nassau County
between Jones Inlet and East Rockaway Inlet, the
shores of New York City between East Rockaway Inlet
and Norton Point, and the shores of Staten Island
between Fort Wadsworth and Arthur Kill.

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

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

OCRACOKE ISLAND. Cooperating Agency: Department of Water Resources,
State of North Carolina.

Problem: To determine the best method of protecting the ocean
and Pamlico Sound shores of the island against erosion
by waves and currents, and providing protection to
State highway and other property.

FORT MACON = ATLANTIC BEACH. Cooperating Agency: Department of
Water Resources, State of North Carolina,

Problem: To develop permanent solutions to halt erosion ana
protect resort improvements at Atlantic Beach and
protect park facilities and historic Fort Macon,

OCRACOKE INLET TO CAPE LOOKOUT. Cooperating Agency: Department of
Water Resources, State of North Carolina,

Problem: To determine the most economical method of restoring the

barrier beach islands to suitable sections and stabilizing
the ocean shore of the islands,

63

OHIO

SHEFFIELD LAKE VILLAGE. Cooperating Agency: Division of Shore
Erosion, Ohio Department of Natural Resources,

Problem: To determine the best method of restoring and improving
the beach fronting Sheffield Lake Community Park to
provide a public bathing beach and to protect the
upland property against erosion.

PUERTO RICO

PT. SALINAS TO PT. VACIA TALEGA (SAN JUAN). Cooperating Agency:
Department of Public Works, Commonwealth of Puerto Rico.

Problem: To determine most practical and economical method
of preventing further erosion of the shore and
stabilizing or restoring the beach, especially aimed
to protect existing upland properties and future
recreational, industrial or residential development
areas.

SOUTH CAROLINA

HUNTING ISLAND. Cooperating Agency: State Highway Department of
South Carolina.

Problem: To determine the best method of arresting erosion and
stabilizing the beach at Hunting Island Beach.

VIRGINIA
VIRGINIA BEACH. Cooperating Agency: Virginia Beach Erosion Commission.
Problem: To determine to what extent assistance from the Federal
Government may be extended under the provisions of Public
Law 826, 8th Congress, in carrying out the periodic

nourishment program of the existing beach restoration
project at Virginia Beach,

64