The Bulletin of the Beach Erosion Board

DEPARTMENT OF THE ARMY
_-CORPS OF ENGINEERS

THE

BULLETIN

OF THE

BEACH EROSION BOARD

OFFICE, CHIEF OF ENGINEERS
WASHINGTON, D.C.

VOL. 8 APRIL 1, 1954 NO. 2

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TABLE OF CONTENTS

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Tidal Gurrent Meters @eeoeeeneasueeeuvreeeeeoeeor2re2ee002802880 0 1
Progress Reports on Research Sponsored by the

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Beach Erosion StudieS .cccoccccceccccccccevccscocce 14

DEPARTMENT OF THE ARMY
CORPS OF ENGINEERS
BEACH EROSION BOARD

VOL. 8 NO. 2

1 APRIL 195)

WOM

TIDAL CURRENT METER

The following article is the compilation of correspondence
between the Beach Erosion Board and the Bureau of Reclama-
tion in Denver, Colorado. It is presented to bring the
findings to the attention of research workers and others
having an interest in measurement of water velocities. The
development and testing of modified forms of the Pegram Meter

was done under the direction of Walter H. Price, Chief, Engi-
neering Laboratories Branch, Design and Construction Division,
Bureau of Reclamation, Denver, Colorado. For a discussion of
the Pegram Meter reference is made to the article "Somervell
on Effect of Turbulence on Current Meters," Trans. ASCE, Vol.
95, Pe. 800.

The Beach Erosion Board and its predecessor in the Corps of Engi-
neers, The Board on Sand Movement and Beach Erosion, have been interested
since about 1930 in finding a current meter which would not only give
reasonably satisfactory measurements with varied flow, but one which
would also record reversals in flow and currents of very low velocity.

A meter originally designed by Dean G. B. Pegram of Columbia University
appears to more nearly approach these requirements. The original Pegram
meter consisted basically of a very lightweight h-bladed propellor mounted
in glass bearings on a horizontal shaft. The propellor was made to have

as nearly neutral buoyancy in water as possible by making a sealed hollow
hub. Revolutions of the propellor for this meter were counted and recorded
electrically by fitting two poles on the frame of the meter, insulated
therefrom, and connecting them to a recording galvanometer. Two opposing
blades of the propellor were fitted with rubber tips, the passage of which
past the poles caused a characteristic mark on the recorder.

The Beach Zrosion Board has made limited use of the Pegram meter in
its laboratory research studies, and due to the instruments relatively
delicate and critical structural members, it has never been adapted to exten-
sive use in the field. However, the Bureau of Reclamation has recently de-
veloped and made certain modifications to the design of this meter and has
successfully employed it for measuring flow in channels under tidal influ-
ence. Facts concerning its development and use of the modified meter were
recently furnished by the Bureau of Reclamation.

The meter as modified by the Bureau of Reclamation is usable for more
applications than the original design because of its more rugged construc-
tion, but it still employs the basic principles of operation of the Pegram
meter. The Bureau design was devised to measure the net flow in the Delta
Cross Channel, which is an artificial channel connecting the Sacramento
River with Georgiana Slough in the Central Valley of California. Both
natural waterways are subject to tidal influence, and consequently the flow

in the artificial channel fluctuates through an imposed tidal cycle.
Further contemplated use for the meter by the Bureau is the making of
net flow measurements over a number of tidal cycles in other channels

of the Delta, thereby obviating large survey crews working for pro-
longed periods with conventional current meters. Principal require-
ments governing the development work were to produce a meter which
would measure flow in either direction without physical rotation of

the entire meter, and one which would produce a recording so that it
could operate unattended. The predetermined velocity range was from

0 to 5 feet per second, the aim being to measure as close to zero
velocity as possible. Calculations from tidal cycle measurements showed
that should the meter not indicate velocities under 0.25 of a foot per
second, less than 1 percent of the net total transferred volume would be
unrecorded.

Figure 1 shows the first meter built in the Bureau's shops. This
meter was installed in the cross channel in the fall of 1952 and func-=
tioned satisfactorily for a continuous period of five weeks. Figure 2
shows a further modified design which was used in the summer season of
1953. The frame as shown by Figure 2 is 11 1/h inches in diameter and
has been strengthened by adding a circular plate immediately below the
coupling of the supporting pipe. This plate is of such a diameter as to
allow anchoring to the stainless steel electrode holders. It serves to
reduce the moment at the coupling itself by distributing the load to the
rings at a distance away from it. A stud was incorporated into the coup-
ling to allow use of l-inch double-strength pipe instead of 1/2-inch pipe.
In order to prevent loss of the rotor assembly in case floating debris
breaks a pivot, there is attached to each pivot housing a circular ring of
stainless steel. Each ring has a slide fastener to position the ring half
way up and around the hub end of the rotor assembly, but does not, of
course, have contact with the hub end.

In an attempt to reduce bearing friction, a synthetic sapphire jewel
bearing was substituted in the bearing housing for the pivot ball bearing
of the original Bureau design. Outside dimensions of the bearing housing
remained the same, but the inside aperture was made to fit the mounted
jewel as received from the manufacturer. When the jewel is used the pivot
point must be correctly ground to fit the cup of the jewel. However,
jewel bearings are no lenger being used in the modified meter, The jewels
should have an advantage over ball bearings since they would tend to be
self-flushing and better resist the corrosive action of salt wear. How-
ever, although wearing qualities under laboratory conditions seemed good,
in field operation floating debris strikes the meter frame causing a mo-
mentary distortion which allows the pivots te fall free of the jewel cups.
Upon springing back into normal position the pivot point is apt to crack
the jewel.

In the modified meter shown in Figure 2, the vanes were enlarged,
new inner end dimensions being 1 inch instead of 7/8 inch, and outer ends
being 2 inches instead of 1-1/4 inches. The length remained the same.
Spacing between the insulator and the electrede was set at 0.03 of an inch.

This small clearance assures a positive reaction on the bridge balance
of the electronic component.

The operation of the wide-vane rotor in the summer of 1953 showed
that the pivots to which Stoody #6 hardfacing had been applied seemed
to wear faster than those used in the rotor with narrower vanes. Later
examination by means of hardness tests revealed that the facilities for
applying the hardfacing to a stainless steel pivot body did not permit
the necessary degree of temperature control. As a result the pivot
often had a hardness lower than either the stainless steel body or the
hardfacing. This would account for one set of pivots exhibiting a
reasonable wear record while a following set would fail in a very short
time. The most satisfactory pivot at the present time is one with a
stainless steel body and a point of Stoody #6 hardfacing set into the
body. This unit is used in combination with the pivot ball bearing
units.

Changes in the electronic recording circuits were necessitated
when it was found that the meter was sensitive to the amount of total
dissolved solids present in the water. Revised circuits are shown in
Figure 3. The form now in use cannot be moved from one location of a
certain dissolved solids concentration to another of different concen=
tration without making considerable adjustments. If the new dissolved
solids count were many times that of the original station some alteration
of the circuits might be required.

Experiments are now being carried on to eliminate the sensitivity
to dissolved solids. Progress thus far has shown that use of electromag=
nets as electrodes and vane feet of nonmagnetic metal can probably be
developed to a satisfactory standard. It is hoped that with a few minor
changes in the counter circuit meter, registration will no longer be in-
fluenced by variation in total dissolved solids content of the water in
which it is used. If present experiments prove this to be the case the
meter will be suitable for wider application. Figures ) through 8 are
calibration curves for all meter assemblies rated to date by the Bureau
of Reclamation.

Figure ) is the calibration curve for the original Bureau-designed
meter (Figure 1). This meter would not operate consistently for velocities
under 0.1) of a foot per second. The curve is linear as was the case for
the Pegram meter, and for all other assemblies tested. No attempt was
made to rate the meter above 5.5 feet per second, Pivot ball bearing units
were used for all tests as well as for the period of use in the cross
channel. The pivots were well worn after five weeks in the cross channel,
yet a recalibration showed the angular shift in the rating curve slope to
be very slight. It would seem, therefore, that so long as the pivot can
still turn freely in the bearings without danger of dropping free of them,
the condition of the pivot is not a critical factor. It is believed by
Bureau engineers that hardfacing the entire pivot point will permit al-
most indefinite use because wear should proceed only until the groove in
the point is of sufficient area to carry the maximum thrust encountered.

Figures 5 and 6 and Figures 7 and 8 should be considered in pairs.
Two modified meters were built for use in the modified frame of type
shown in Figure 2. They have been designated on the curves as Meter
No. 1 and Meter No. 2. Meter No. 1 was the narrow-vane meter. Meter
No. 2 was built of the hub ends and spiders from the original meter and
a new axle and wider-vane assembly. Both meters were rated for pivot
ball bearings and jewel bearings. There is no difference, of any
practical significance, in the calibration curvesfor the two types of
bearings in the same meter. There is a difference in curves for Meter
No. 1 and Meter No. 2, which fact serves only to emphasize that each
meter of any design must receive a separate calibration. That there is
no comparable difference in bearing types is significant, and seems to
indicate that friction had been reduced to a practical minimum with use
of the pivot ball bearings. The lower limit of operation for both meters
is 0.12 of a foot per second.

The original meter with the narrower vanes was almost buoyant in
water. Adding width to them, of course, was done at a sacrifice of that
buoyancy. It is believed that restoring the original vane size would not
materially aid in obtaining operation at velocities lower than 0.12 of a
foot per second. The vanes had been enlarged in an attempt to gain a
higher turning moment, but it appears that the maximum usable area had
been reached on the first meter. It should be recognized that the vane
shape was decided upon through consideration of geometric factors alone,
and that no propeller design theories or practices were employed.

It is pointed out that no provision has been made for indicating the
direction of flow on the recording, as was done with the Pegram meter.
This was not necessary because the curve of velocity drawn by the recorder
is roughly the sine curve, and comparison with the curve shown by a tidal
stage recorder located nearby, readily sets the direction of flow. The
pattern is repetitive, and changes in direction take place slowly over
periods of 2 to 6 hours. Without the direetional feature it is possible
to use insulators on all vanes to obtain a higher input count to the counter
circuit. This is an advantage, particularly at low velocities.

In summary, the Bureau of Reclamation has a current meter which
satisfies its present requirements. Though some additional development
work might produce an improved design which would operate at lower veloci-
ties, it contemplates no further effort in that direction.

FIGURE | - TIDAL CURRENT METER
(DEVELOPMENT BY BUREAU OF RECLAMATION)
5

FIGURE 2 - TIDAL CURRENT METER
(FINAL MODIFICATION )

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Water Velocity-Feet Per Second

Water Velocity-Feet Per Second

Water Velocity -Feet Per Second

Meter (Fig. 1)

rve is average of four

libration curves.

2

3 4 5 6

Rotor Revolutions Per Second

2 3

Rotor Revolutions
FIGURE

4 5
Per Seconds
5

Rated 5-8-53

No. 2 - Ball Bearings —-+

2 3
Rotor Revolutions
FIGURE

: Meter No.2 has chrome |

plating onthe h

4 5
Per Second
7

4

ub ends.

FIGURE 4

Water Velocity- Feet Per Second

3 4
Rotor Revolutions Per Second
FIGURE 6

5 6

Water Velocity -Feet Per Second

Meter No. 2-
| Rated 5-8-53
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Jewel Bearings

2

3

e: Meter No. 2 has chrome
plating on the hub ends.

4

4

5 6

Rotor Revolutions Per Second

FIGURE 8

CALIBRATION CURVES-TIDAL CURRENT METERS

PROGRESS REPORTS ON RESEARCH SPONSORED BY
THE BEACH EROSION BOARD

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

I. University of California, Contract No. DA-l9-055-eng-8, Status

Report No. 13, 1 Dec. 1953 through 1 March 195h.

The report entitled "Bore Hole Studies of the Naturally Impounded
Fill at Santa Barbara Breakwater, California", Institute of Engineering
Research, Waves Research’ Laboratory, Technical Report Series 1, Issue
1h, by Parker D. Trask and Theodore Scott, was submitted to the Beach
Erosion Board on 18 January. Insofar as is known, this is the first
attempt that has been made to drill holes through a natural accumulation

of sand above a shallow water offshore area in order to study sedimentary
processes.

The mechanical analysis of the sand samples collected during the
course of the survey of the movement of sand around rocky promontories
of Point Arguello, Point Conception and Point Dume in Southern California
is, as of 28 February 1954, approximately 35 percent complete.

During the latter part of February a series of sand samples taken
at mathematical intervals was obtained at two localities off the coast
at Point Heyes, in order to determine the variability of individual
samples taken upon a beach which was known to be irregular in composition.
Previous studies of sample errors have generally heen made upon beaches
that ostensibly vary very slightly. This study at Point Reyes was
carried out with the object of showing how reliable an individual sample
could be upon a beach known to be irregular in composition.

II. University of California Contract No. DA-9-055-eng-17, Status

Report No. 3 - 1 October to 31 December 1953.

The experimental work with a movable bed was completed and a report
submitted entitled "Sand Movement Mechanics in Deep Water" by Madhav
Manohar. Part I of this report dealt with the mechanics of sand move-
ment on sandy beds in relatively deep water due to the action. of
oscillatory waves of small amplitude and long wave length. On the assumption
that the bottom water oscillations were nearly simple harmonic motions,
sand movement mechanics were studied by oscillating a section of the bed
horizontally through still water. Only that part of the sediment load
which rolls, or creeps along the bottom, as distinguished from suspended
load which is carried in the fluid in suspension was considered in this
report. Its initial and general movement, the critical velocities and
horizontal amplitudes required for such movements, the conditions of flow
at the interface - whether laminar or turbulent - were axperimentally

9

measured and analyzed theoretically for grains of various sizes and
densities.

Part II of this report pertains to ripple formation. The term
ripples is used to indicate the systematic series of undulations or waves
that are observed to form an the bed at certain critical velocities.
Natural ripples are formed at velocities greater than those required for
general movement, where natural ripples are those generated directly on a
smooth bed by the intense movement of the particles, and not by conspic-
uous external obstructions which tend to hasten their formation even at
much lower velocities. It was the objective of the explanation in this
part of the report to examine the phenomenon of natural ripple formation.
In this study experimental observations were limited to the initial
formations of the natural ripples and as such experimental analysis was
limited to that stage.

This report will be published as a Technica] Memorandum of the
Beach Erosion Board during the summer of 195k.

III. University of California, Contract No. DA-l9-055-eng-31, Status
Report No. 2 - 1 Nov to 31 Jan 195).

1. The installation and calibration of instruments for measuring
waves, Wind, pressure drop and wind tides has been completed.

Bo The following measurements are made for each experimental run:

a. The wind set-up at 5 locations along the center line of
the channel.

b. The vertical wind velocity distribution at 3 locations in
the channel by use of a pitot tube.

c. Wave measurements at 4 locations along the channel. At
each of these 4 points of measurement a continuous surface
time history is obtained over a time period of approximately
one hour so that it is possible to evaluate the data for
mean, significant and meximum waves as a function of the
duration of the wind.

3. Experiments in progress involve the following wind and channel
conditions:

a. Five different average wind velocities.

b. Seven different still-water depths.

ce All the above mentioned conditions are to be conducted for
both rough and smooth bottoms of the channel.

IV. Scripps Instituticn of Oceanography, Vontract No. DA-49-055-en
Quarterly Progress Report No. 18 - Oct. to Dec. 1953.

-3,

The variability of orbital velocities is being compared with the
variability of the waves generating them. Comparisons are made from
20-minute records which represent widely different conditions.

10

The underwater work with reference rods has indicated changes in
the bottom level in excess of 2 feet in shallow water; changes in water
deeper than 30 feet have been very slight.

The observation and measurement of ripples has been extended to
include two coarse sand areas. The large size of the ripples in coarse
sand permits direct observation of grain motion and selective sampling
of sand from ripple crest and trough. Generally sand from the ripple
crest is slightly coarser, better sorted, «nd skewed more toward coarser
particle sizes than that from adjacent troughs.

Between 30 November and 15 December a submarine slide took place in
the Sumner Branch and South Branch of Scripps Submarine Canyon. The
slide was. first reported by divers and was confirmed by an echo=sounding
survey which showed that the maximum change was a deepening of 9 feet.
The divers had reported larger changes but these were in the narrow
gorge, where echo-sounding is inaccurate. Stakes have been driven into
the canyon walls which will allow comparative measurements to the canyon
floor.

Vie The Agricultural and Mechanical College of Texas, Contract No.
DA-0-055-eng-16, Quarterly Report for period ending 3] January 195h.
le Field Operations, Field operations were continued at the Sun

Oil Pier at Caplen,Texas, Simultaneous 20-minute records being taken
twice daily at both shoreward and seaward end of the pier.

A third recorder has been installed temporarily on a Magnolia Oil
platform south of Morgan City, Louisiana, and records are being taken
periodically. The mean water depth at this site is 0 feet.

The analysis of all wave records obtained at Pure Oil Structures A
and B has essentially been completed. The analysis of wave records ob-
tained at the Sun Oil Pier and Magnolia platform is in progress.

2. Theoretical Investigations. Computations involving the combina-
tions of wave generation and wave energy loss due to bottom friction have
been completed for the case of a shallow bottom of constant depth.
Computations for a bottom of constant slope have continued.

VI. New York University, Contract No. DA-)9-055-eng-32.

Work was continued on the development, design, and manufacture
of a spectrum analyser for wave records, and on the statistical analysis
of hindcast wave data along the Atlantic Coast obtained by the Neumann-
Pierson methods. In addition, a report "On Ocean Wave Spectra and a
New Method of Forecasting Wind-Generated Sea" by Gerherd Neumann was
published as Technical Memorandum Number 3 of the Beach Erosion Board.

11

VII. Massachusetts Institute of Technolo Contract No. DA=-)9-055-eng-16.

th Progress Report dated 12 February 195h.

dhe To determine the proper statistical sample size of the test sedi-
ments, a study was made of the motion of 1/8" cellulose acetate spheres
in individual sample sizes of 20, 30, 40, 50, and 60 spheres under the
action of the same wave. On the basis of the derived set of distribution
curves as a function of time and distance, a sample size of 50 was
selected as being the smallest having the correct statistical distribu-
tion.

2. Three more tests were carried out to check reproducibility of
results with this sediment sample size, and also the effect of the last
wave generated in each increment of time. It appears, on the basis of the
first increment where all samples had the same starting position, that
a number of runs will have to be averaged to give the correct velocities.

36 It was found that for each combination of wave geometry, beach
and particle properties, there is a point on the beach slope at which
the gravity force is in balance with the drag forces on the sphere. This
point divides motion of the particles into onshore and offshore trans-
portation.

Lh. Recording the transverse positions of the particles shaal a
steady migration of the center of gravity of the sample toward one wall.
This may be due to the effect on the wave motion of slight misalignments
in the channel walls.

VIII. Waterways Experiment Station, Vicksburg, Mississippi. -

Wave Run-up on Shore Structures - Overtopping tests on a step-faced
seawall with a seaside slope of 1 on 13 and a beach slope of 1 on 10

were completed for the 25 and 3h-foot depths, and for the 3- and 6-foot
crest elevations for the 29.5 foot depth. Testing was then discontinued
due (1) to lack of funds, and (2) to permit initiation of testing on a

1 on 3 smooth slope similar to the Lake Okeechobee levee section. An
expanded program of wave conditions will be used in these new tests.

Effect of Inlets on Adjacent Beaches - This test, having in 450 tida)
cycles successfully reproduced several cycles of migration of the tidal

inlet, was discontinued, and the results of the test are now being
analyzed.

IX. Beach Erosion Board, Research Division, Project Status Report for
Quarter ending 15 March 195].

In addition to the research projects under contract to various
institutions which are reported on above, the Research Division of the

12

Beach Erosion Board is carrying out certain projects with its own
facilities. The main unclassified projects have been described in pre-
vious numbers of the Bulletin, and a short description of some of the
work accomplished through the last quarter is given below.

Project ESMOND - A final report was prepared and sbheduled for
publication in the summer of 1954. A search is being made for reports
of prior work (prototype or model) on the maneuvering of ships through
fluids having densities (and viscosities) different from water, and
information supplied bearing on this project would be appreciated. A
short field test was made by the Philadelphia District.m the maneuverability
of an oil tanker in the Delaware River, and particularly in travelling
over and through mud shoal areas.

Study of Reforming of Waves After Breaking - A wave tank study has
been initiated to define the conditions under which waves will reform

after breaking, and the relationship between the energy transmitted forward
by the initial unbroken wave and that of the reformed wave.

Instrument Development - A sinusoidal dynamic calibrator is being
made to enable determination of the time effects of moving water (as
meniscus) on wave gage calibration, particularly for waves of very low
amplitude.

Routine progress, testing. and analysis,has been made on the other
projects being carried out by the Research Division. In addition, a
small project was carried out for the Fish and Wildlife Service and the
Geological Survey involving the testing and development of small
dampeners which could be placed on a sand flat or beach and allow tidal
circulation but break up the oscillatory wave currents which mold the
bottom into a ripple pattern and constantly stir the top layer of sand;
these dampeners would provide a shelter where seed clams could get an
anchor without being distarbed by the moving sand. Several types were
developed that were deemed worthy of further study, and prototype field
trials of these were~recommended.

13

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 a list of authorized cooperative studies follow.

SUMMARIES OF REPORTS TRANSMITTED TO CONGRESS
HAMPTON BEACH, NEW HAMPSHIRE

The area studied is located in the Town of Hampton in the southeast
corner of New Hampshire. It comprises the shore of the Atlantic Ocean
between the headland known as Great Bears Head and the entrance to Hampton
Harbor, a distance of 1.8 miles. The shore area is extensively developed
for recreational use. The permanent population of Hampton is about 2,850.
The summer population was estimated at 21,500 in 1945, since which date
additional facilities have provided for a larger summer population. Large
numbers of daily visitors also use the beach. The shore is owned by the
State, extept for about 0.2 mile which is owned by the Town and leased for
private cottage use.

Hampton Beach consists of a barrier bar or spit extending south-
ward from Great Boars Head, the remains of a glacial drumlin. Erosion of
that headland formerly supplied ample material to the beach to the south
but protective works and the residue of coarse material have reduced the
supply of material to the beach. Consequently the beach has slowly
deteriorated. The problem area is about 1.3 miles in length between Great
Boars Head and Haverhill Street. The shore boulevard along this area is
partly protected by a seawall. The width of beach seaward of the wall
decreases in width northward, and the size of beach material increases
in that direction from fine sand to cobbles and boulders at Great Boars
Head.

Tides in the area are semi-diurnal, the mean range at Hampton River
being 8.3 feet. The spring range is 9.6 feet. The maximum tide of record
at Portsmouth, about 12 miles to the north, was 3.9 feet above mean high
water. Tides 3 feet or more above mean high water occur about once in
2 years.

Hampton Beach is exposed to waves from the northeast, east and south-

east. The fetch to the northeast is limited by Nova Scotia, about 250
miles distant, but the Isles of Shoals about 11 miles away also afford

1h

some protection from waves from the northeast. The fetch to the east is
unlimited. Cape Ann, 17 miles to the southeast, limits the fetch in
that direction. Storm: waves which cause the greatest movement of beach
material are those from the northeast . The predominant direction of
littoral drift is southward.

The Division Engineer and the Beach Erosion Board concluded that the
most suitable plan for protecting, restoring, and improving Hampton Beach
north of Haverhill Street consists of direct placement of sand fill along
the+shore to widen the beach to a general width of 150 feet, with an added
25-foot widening along 1,250 feet of the northern end of the fill area.
They also found that protection and improvement of Hampton Beach are
justified by evaluated benefits and recommended adoption of a project by
the United States authorizing Federal participation, subject to certain
conditions, by the contribution of Federal funds in an amount equal to
one-third of the first cost of the plan. The estimated total cost and
Federal share are respectively $420,000. and $140,000.

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

SEEKIRK SHORES STATE PARK, NEW YORK

Selkirk Shores State Park comprises about 1] mile of shore at the
southeastern corner of Lake Ontario. It is located in the Town of Rich-
land, in Oswego County about 15 miles northeast of Oswego Harbor. It is
conveniently located with respect to the population centers of Oswego
Syracuse, Rome and Utica, which have a combined population of over 385,000
The park has been developed with cottages, camping facilities, bathing
beach, picnicking and parking areas.

The shore in the vicinity of the park comprises bluffs of glacial
till alternating with barrier beaches across the drainage courses. The
exposed drumlins south of the study area furnish gravel and cobbles to
the shore. The barrier bar fronting Grinstone Creek is composed of this
material. North of this bar the bluff rises gradually to a maximum
height of hl feet, thence decreases to the bar fronting the Salmon River.
This bar has a gravel and cobble beach backed by sand dunes which have a
maximum height of 60 feet. The streams flow through marshes and furnish
no material to the shore.

Lake Ontario is about 190 miles long and 50 miles wide. The mean
lake level for the months of March to December is about 2 feet above the
established low water datum. The highest lake stage and the highest
monthly mean recorded at Oswego, New York, are respectively about 6.2
and 5.3 feet above low water datum. Storms cause changes in lake levels
as winds move the water toward the ends of the lake. The design lake
stage is 6 feet above low water datum. Of winds which generate waves
affecting the area, those from the west have the greatest fetch, about
176 miles. During severe storms with a frequency of about once a year,
waves may range up to 12 feet in height in deep water, but ordinarily
waves of this height would break before reaching shore structures.

ie

Storm waves which cause the greatest movement of beach material are
those from the west. The predominant direction of littoral drift is
northward.

The Division and District Engineers and the Beach Erosion Board
concluded that the most suitable plan for the protection of Selkirk
Shores State Park consists of: (a) the construction of an outlet
structure, consisting of two jetties to form an outlet channel to carry
Grindstone Creek through the barrier beach and into the lake to prevent
migration of the creek mouth and to stabilize the adjacent shore; (b)
the restoration of approximately 900 feet of beach frontage by altera-
tion of an existing groin, construction of a new groin and placement of
sand fill. The southerly half of the beach area would be compartmented
between the proposed outlet structure and the existing groin which would
require alteration. The northerly half would be compartmented between
the same existing groin and the new groin; and c) protection of the
shore northerly of the beach areas by means of a roadway-type quarry-
run stone revetment. They found that protection and improvement of the
shore at Selkirk Shores State Park are justified by evaluated benefits,
and recommended adoption of a project by the United States authorizing
Federal participation, subject to certain conditions, by the contribution
of Federal funds in an amount equal to one-third of the first cost of
the plan. The Board believes that stone would be preferable to steel
for construction of the new groin. The Board also considered that in
order to avoid scour north of the new groin, the revetment adjoining
the groin should be widened to 25 feet tapering thence to 10 feet at a
distance of 25 feet to the north.

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

STATE OF OHIO, EUCLID TO CHAGRIN RIVER

The area studied is located in Cuyahoga and Lake Counties on the
south shore of Lake Erie adjacent to and east of Cleveland, Ohio. It
lies between the Cleveland-Euclid boundary and Chagrin River a distance
of about 8 miles. The area includes the shore line of the city of
Euclid, the villages of Willowick, Lakeline, Timberlake and a portion
of Eastlake. The property along the shore line of the study area has
been developed mainly for private residential and recreational purposes.
Publicly owned portions of the shore are limited to Euclid City Park,
300 feet of frontage at 23131 Lake Shore Boulevard also owned by the
city of Euclid, and street ends. Euclid City Park is the site of a
sewage disposal plant, and a beach impounded there by the outfall
structures affords ample protection to this frontage. The other 300
feet of city-owned frontage is undeveloped and eroding at a moderate rate..

The shore line of the study area consists of easily eroded bluffs
of boulder clay and shale varying from 25 to lO feet in height, fronted
by sand beaches up to 200 feet in width at mean lake level. The wider
beaches are generally the result of impounding of littoral drift by
structures built for ther purposes such as sewer outlets or navigation

16

improvements. The narrow natural beaches are submerged at high lake
levels. It has been estimated that about 20 percent of the bluff material
within the study area is suitable for beach building. Erosion of the

beach and bluffs along the shore of the city of Cleveland east of Cleveland
Harbor and in parts of the study area is now supplying considerable beach
material by means of the slight dominance of eastward littoral drift.
Beaches west of the study area have been steadily reduced in width by
erosion during the past 20 years.

Miscellaneous groins, walls, and breakwaters have been constructed
in an attempt to prevent erosion of the shore. Short groins have gen-
erally caused minor accretion on their west sides and have reduced
recession of the bluffs to some extent, but the majority have been too
short and low to be fully effective. The accretion west of the outfall
structure at Euclid City Sewage Disposal Plant and the west jetty at
the mouth of Chagrin River indicates an eastward predominance of
littoral drift.

The mean lake level for the months of March to December is about

1.6 feet above the established low water datum. The highest lake stage
and the highest monthly mean recorded at Cleveland, Ohio, are respectively
about 5.2 and feet above low water datum. Storms cause changes in

lake levels as winds move the water toward the ends of the lake. Of
winds which generate waves affecting the area, those from the northeast-
erly quadrant have the greatest fetch, about 150 miles, but for the ice-
free period those from the northwesterly quadrant apparently have the
greater effect on material moverents. It is estimated that, consider-
ing the effect of wind set-up during easterly storms to be about 1/2 foot,
the lake could reach a level in the study area of about 4.5 feet above
low-water datum. During severe storms waves may range up to 10 to 12
feet in height in deep water, but ordinarily waves of this height would
break before reaching shore structures. The maximum height of waves
breaking landward of low water datum shore line at a design lake stage

of 4.5 above low water datum would be 3.5 feet. Existing groins with
shore ends from about 5 to 7 feet above low water datum indicate that
these elevations are generally adequate to impound a low protective beach.
A beach 30 feet in width between the water line at design lake stage of
4.5 feet above low water datum and elevation 8 feet above low water datum
is considered the minimum necessary to protect the bluffs in the study
area from erosion by wave action. In those areas where a beach presently
exists, it may be built or maintained to the required minimum dimensions
by construction of suitably designed groins. However, as more of the
shore. line is protected the natural supply of beach building material
through littoral drift may be expected to decrease, and additional
maintenance by adding material artificially may be necessary. In those
areas where no beach presently exists and none is desired, the bluff may
be protected by a seawall with top elevation of 8 feet above low water
datum and the slope sbove armored with stone revetment to elevation 12
feet above low water datum. Protection can also be provided by a con-
tinuous belt of heavy riprap at the toe of the bluff extending up to

17

elevation 12 feet above low-water datum. Ice forms a protective coating

over beaches during winter months, but the lifting and battering action
of shifting ice floes during the spring break-up must be considered in

designing shore structures for structural stability.

The District and Division Engineers concluded that there is sufficient
beach material available to provide beaches of the minimum width necessary
to protect the bluffs from erosion by wave action for a considerable
portion of the study area. This material is presently accumulated in a
wide beach that appears to have moved eastward from the shores of Cleveland
to the westerly part of the study area. It can be expected to continue its
eastward movement unless prevented by retarding structures. They concluded
that the most economical method for the protection of a large part of the
shore frontage within the study area is by constructing groins to retard
the movement of this material and retain a suitable beach of minimum
width for protection of the bluff, while permitting the remainder of the
material to continue its movement eastward. Artificial placement of fill
will be necessary to create beaches in the extreme westerly end of the
study area, and at other localities after the greater part of the area
has been protected. They also concluded that an overall plan of artificial
nourishment would have general benefits exceeding those of other plans
considered. Where no beaches now exist, nor are particularly desired,
protection of the bluff can be provided by a seawall or revetment.

The Beach Erosion Board concurred generally in the conclusion that
groin construction is the most economical method of protecting individual
properties, provided only limited reaches of the total shore length are
considered. If the entire shore is involved, the costs would be increased
by an item for artificial placement of fill. The Board also noted that
the estimated annual costs of the revetment and seawall plan, if con-
structed in lengths of over 120 feet, would be somewhat less than those
of the artificial nourishment plan. However, in the absence of a natural
supply of beach material continued erosion may be expected lakeward from
revetments and seawalls. Moreover it noted that the costs of the artificial
nousishment plan were based on available costs without complete
investigation of sources and also include a liberal allowance for mainten-
ance, Considering these factors, the Board was of the opinion that a
complete investigation of sources of material and methods of placement,

a study beyond the scope of the present report, should be made. Such a
study might result in substantial reduction of the estimated costs of a
comprehensive artificial nourishment plan. Considering also the greater
general benefit that would accrue from such a plan the Board concluded
that its economic justification might be found to be greater than that of
any other plan.

The Beach Erosion Board recommended that local interests consider
adoption of a comprehensive plan of protection by artificial placement of
a sand beach, either directly over the entire length, in stockpiles or as
a feeder beach near the west limit of the area, based on their own
determination of economic justification. In the event that protection of
individual properties is necessary, the Board recommended that private
owners consider adoption of the plans of protection by groins, revetment

18

or seawalls, including adequate flank protection, selecting that plan

most suitable to the present condition and desired use of their shore frontage
cqnsistent with the effect on adjacent shore sections. As additional
protection of publicly owned shores is not warranted at this time, and
existing Federal law includes no policy for Federal assistance in the

cost of protecting privately owned shores, The Board recommended no

Federal participation in the cost of the work.

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

LAKE ERIE SHORE OF THE STATE OF OHIO

The Beach Erosion Board in connection with transmitting the last
report on the continuing cooperative study of the Lake Erie shore of Ohio
considered it desirable to summarize the knowledge and conclusions regard-
ing methods of shore protection in Ohio resulting from this investigation
from the viewpoint of the entire shore of the tate and on a long range
basis.

A typical condition found along the Lake Erie shore of Ohio is an
eroding bluff of unconsolidated clay, silt, and sand, As the bluff is
undercut by wave action, or sloughs due to seepage of surface water or
frost action and falls to the beach, the finer fraction of the material
is carried into deep water and the coarser fraction remains to form or
replenish the beach. As the latter material is typically only a small
proportion of the total volume, the beaches thus formed are narrow and
provide the bluffs little protection against wave action.

As indicated in the reports on the several areas, one method of
protecting the bluffs comprises placement of a non-erodible barrier between
the waves and the bluff in the form of a seawall, bulkhead, or revetment.
Such structures cause wave reflections and turbulence. In addition, by
preventing erosion of the bluffs they reduce the amount of sand available
for beach building orreplenishment. In the absence of a natural supply
of beach material, continued erosion may be expected lakeward of the
structures as well as on the adjacent unprotected shores. Because of
their high costs, seawalis, bulkheads, and revetments are usually used
for relatively short frontages, The necessity of flank protection as
adjacent shores recede increases the cost of protection by structures of
these types. The continuing lakeward erosion results in steadily increas-
ing maintenance costs. Initial and annual costs become so high that this
method can be justified only for property of high valuation.

The Board has found that wave energy is absorbed more effectively
by a gently sloping sandy beach than by any other method. With steeper
slopes, coarser material is required for stability. With large stones
the wave absorbing structure become a revetment or rubble mound with
slope approaching 1 vertical to 1 horizontal.

uy)

As stated in certain of the reports on the several areas covered by
the study, groins may be used to a limited extent to assist in accumulat-
ing or retaining a sandy protective beach. The amount of sand naturally
available to the shore is generally insufficient to make this a feasible
means of providing adequate shore protection for any extensive frontage.
Where used effectively for a limited frontage it would reduce the amount
of sand being transported alongshore and adversely affect an adjacent
frontage.

In the absence of a natural supply of beach material, beaches can
be placed or widened by artificial placement of sand on the shore. It
may be placed directly along the full extent of the shore to be protected,
in stockpiles to be distributed by wave action, or as a feeder beach to
provide a continuing supply of material to maintain the existing beach.
Where there are extensive frontages between littoral barriers, artificial
supply of material frequently becomes the least costly method of prevent-
ing recession of the shore line, as the supply of material maintains the
entire frontage.

An investigation of offshore deposits of sand in the vicinity of
Lorain and Fairport Harbors was made in connection with a previous report.
The purpose of this investigation was to locate adequate sources of sand
for the construction of beaches for shore protection and improvement.

Ir was found that large reserves of suitable sand are available in the
deposits investigated. Further investigation may reveal additional de-
posits not presently known.

A complete investigation of sources of sand for beach construction
and maintenance and of methods of placement was beyond the scope of the
reports under the cooperative study. If a comprehensive plan of beach
construction is adopted, more economical methods of placement can in all
probability be developed than are presently available. The Board believed
that the plan of protection by artificially placed and maintained beaches
may be found to be the most econo mical method of protection for any
extensive reach of shore.

As the Board did not consider the economic justification of protection
for any large segment gf shore including both publicly and privately owned
frontages, it could not comment on the relative costs of large scale
protection and the economic cost of gradual toss of Land by recession of
the shore at rates up to nearly 5 feet annually. The latter varies with
the use of the land. Where land is developed with costly manufacturing
or power plants high cost protection is warranted. In the case of unused
land the cost of protection is obviously unjustified. In the latter case
and where buildings can be readily moved landward as the shore recedes,
or have an economic life less than the period until recession caused their
destruction, an alternative solution is to permit continuing recession
of the shore. In this solution, it would be advisable to restrict future
construction to types having an economic life less than the period until
the shore recession reaches their position.

20

As piecemeal protection by walls, bulkheads, and revetments is both
extremely expensive and will agszravate erosion in unprotected areas, the
Board concluded that protection of the shore by artificially placed
beaches is the most practicable means where extensive frontages are
involved. Maintenance of the beaches by artificial means is, of course
an essential part of the plan. If maintained, the plan can be effective
permanently. The Board believed that the annual costs of this plan on
a large scale basis may be found to be less than the costs for any other
plan. In addition to providing protection, the beaches would be available
for recreational use. Considering ail costs and benefits, the Board was
of the opinion that the protective beach plan would probably have substantially
better economic justification than other plans.

The Board recommended that the State of Ohio investigate sources
and costs of placing suitable material and consider the adoption of com-
prehensive plans of protecting extensive reaches of shore by artificial
placement and replenishnent of sandy beaches, based upon its own deter-
mination of economic justification.

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

SHORE OF GALVESTON BAY FROM APRIL FOOL POINT TO KEMAH,
GALVESTON COUNTY, TEXAS

The area studied is located on the west shore of Galveston Bay
about 17 miles north of Galveston, Texas. It includes the shore from
April Fool Point to the mouth of Clear Creek at Kemah, a distance of about
10 miles.

The property along the shore line of the study area has been
developed mainly for private residential and summer resort use. The
principal centers of population are San Leon, Clifton by the vea and
Kemah. The residential population of about 1,000 along the bay shore of
the study area is more than tripled by summer residents. Many additional
persons visit the area over summer weekends. The shore is privately
owned except for ends of public streets extending to the shore. Although
some pollution of bay waters may exist, it is insufficient to render the
shore area undesirable for residential use.

The shore cf the study area consists of a narrow sandy beach in front
of a steep eroding bluff composed principally of sandy clays. The top
of the bluff varies in elevation from about 10 to 17 feet above mean
sea level. Little of the bluff material is of sufficient size for beach
building. Sections of the bluff slough off and fall to the beach during
the rainy season. They disintegrate under wave action and most of the
material is carried offshore. The short local wind waves characteristic
of the bay are not of the type that would tend to return material to the
shore. Over the period of record, the shore from April Fool Point to
a point about 2 miles north of Edwards Point receded an average of about
lh feet annually, thence north to Clear Creek the recession averaged
about 2 feet annually.

21

Miscellaneous revetments, seawalls, bulkheads and groins have been
constructed by private owners in an attempt to prevent erosion of the
shore. The ineffectiveness of groins in causing accretion indicates a
lack of movement of beach material alongshore. The other types of structures
have been generally effective against normal erosion, but many have
failed as a result of storm wave action or flanking.

The mean range of tide in Galveston Bay is about 1 foot. The highest
tide of record in the bay area was 14.5 feet above mean sea level.
Tides of 5 feet or more above mean sea level occur on the average only
once in about 8 years. Maximum tidal stages accompany southerly winds
and minimum stages result from prolonged northerly winds. The study area
is exposed only to waves generated in Galveston Bay. Due to the shallow
depth of the bay at normal tidal stages, wave action against the bluff
at such stages is negligible. The shore between April Fool and Edwards
Points is exposed to waves from the southeast and east. Such waves
are generated by south to east winds which also cause above normal tidal
heights along this section of shore. At storm tidal stages over 3 feet
above mean sea level, which occur on the average only once in about 2
years, waves up to about 2 feet in height probably break against the
bluff. still larger waves probably reach the bluff during the more
infrequent hurricanes with tides of 8 feet or more. Such waves are the
most destructive forces affecting the shore. The cost of protecting
against such infrequent conditions is prohibitive. North of Edwards
Point the alignment of the shore is such that it is exposed only to waves
from the north and northeast. As northerly winds do not increase, but
tend to reduce tidal stages, the bay is shallower than during southerly
storms. Consequently, large waves break before reaching the bluffs along
this shore and it is believed that the maximum wave height at the shore
under those conditions does not exceed 1.5 feet.

The District and Division Engineers and the Beach Erosion Board
concluded that the most practicable and economical plan of protection con-
sists of a dumped mound of quarry-run stone with a filter blanket of
shell to prevent leaching of clay from behind or beneath the mound.

The minimum top elevation of the mound would be 5 feet above mean sea
level from April Fool Point to Edwards Point, thence 3 feet above mean
sea level to Kemah. The bank would be graded on a slope not steeper
than 1 on and seeded and sodded behind the top of the mound. Since
the shores of the study area are privately owned and existing Federal
law does not include a policy of Federal participation in the protection
of such shores, they recommended no Federal participation in the cost of
any protective work.

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

22

ANAHEIM BAY HARBOR, CALIFORNIA

Anaheim Bay Harbor is located on the Pacific Ocean coast of

Southern California in Orange County, about h miles southeast of the mouth
of the Los Angeles River at Long Beach. The adjacent shore communities

are SealBeach to the west with a population of 3,558 and Surf Side and
Sunset Beach to the east with a combined pepulation of about 1,550. Orange
County has a total population of about 214,000. The development of the
shore communities is principally residential. The beaches are used ex-
tensively for recreational purposes.

The Seal Beach shore with a frontage of 6,100 feet is publicly
owned. Adjacent to the Anaheim Bay east breakwater, there is a Federally
owned frontage of 900 feet. The remainder of the Surf Side shore, amount-
ing to 3,200 feet, is privately owned. The Sunset Beach shore, 6,200
feet in length, is publicly owned. Anaheim Bay has been developed as a
harbor by the United States Navy. The entrance thereto is protected by
two converging breakwaters.

The District and Division Engineers and the Beach Erosion Board con-
cluded that the most suitable plan of protection of the shore in Orange
County, California from San Gabriel River to Los Patos Avenue in Sunset
Beach, comprises artificial placement of approximately 200,000 cubic
yards of sand on the shore and construction of one groin at Seal Beach,
and placement of a feeder beach in amount of approximately 1,000,000
cubic yards of sandat Surf Side. They found that such protection is
economically justified and recommended Federal protection in an amount
equal to the portion of the cost applicable to protecting the Federally
owned frontage plus one-third of the first cost of measures for the
restoration and protection of the other publicly owned portions of the
shore in Orange County, California from San Gabriel River tc-Los Patos
Avenue in Sunset Beach. The estimated first cost and Federal share
arerespectively for Seal Beach $186,000 and $62,000 and for Surf Side
and Sunset Beach $300,000 and $86,)00.

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

23

AUTHORIZED COOPERATIVE BREACH EROSION STUDIES
MASSACHUSETTS

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

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

CONNECTICUT

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

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

NEW YORK

FIRE ISLAND INLET AND VICINITY; Cooperating Agency: Long Island State
Parks Commission.

Problem: To determine the most practicable and economic method of
providing adequate material to maintain the shore in a
suitably stable condition and an adequate navigation
channel at Fire Island Inlet.

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

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

NEW JERSEY

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

Problem: To determine the best method of preventing further erosion
and s tabilizing and restoring the beaches, to recommend
remedial measures, and to formulate a comprehensive plan
for beach preservation or coastal protection.

2h

DELAWARE
STATE OF DELAWARE: Cooperating Agency. State Highway Department.

Problem: To formulate a comprehensive plan for restoration of
adequate protective and recreational beaches and a program
for providing continued stability of the shores from Kits
Hummock on Delaware Bay to Fenwick Island on the Atlantic
Ocean.

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

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

ALABAMA

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

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

LOUISIANA

GRAND ISLE. Cooperating Agency: Department of Public Works, State of
Louisiana,

Problem: To determine the best method of preventing further erosion
of the beaches along the Gulf shore ofGrand Isle.

CALIFORNIA

STATE OF CALIFORNIA. Cooperating Agency: Department of Public Works,
Division of Water Kesources, 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 Santa Cruz and San Diego
areas.
WISCONSIN
KENOSHA. Cooperating Agency: City of Kenosha.

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

25

MANITOWOC-TWO RIVERS. Cooperating Agencies: Wisconsin State Highway
Commission, Cities of Manitowoc and Two Rivers.

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

TERRITORY OF HAWAIT

WAIMEA & HANAPEPE, KAUAI. Cooperating Agency: Board of Harbor Commissioners,
Territory of Hawaii.

Problem: To determine the most suitable method of preventing erosion,
and of increasing the usable recreational beach area, and

to determine the extent of Federal aid in effecting the
desired improvement.

26

Pe.
pease

*