• TABLE OF CONTENTS
HIDE
 Front Cover
 Title Page
 Table of Contents
 Program
 The coastal engineering research...
 Emergency beach protection for...
 Low cost protective devices for...
 Environmental monitoring of the...
 Shoreline stabilization and its...
 Political problems of erosion control,...
 Nature assisted beach enhancement,...
 Rebuilding the beaches of Florida,...
 Tidal inlet control of beach erosion...
 Beach erosion - Long and short...
 Addendum






Group Title: Technical paper - Florida Sea Grant Program ;, no. 7
Title: Papers presented at Beach Seminar '78 October 4 through 7, 1978, South Seas Plantation, Captiva Island, Fla.
CITATION PAGE IMAGE ZOOMABLE
Full Citation
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Permanent Link: http://ufdc.ufl.edu/UF00072258/00001
 Material Information
Title: Papers presented at Beach Seminar '78 October 4 through 7, 1978, South Seas Plantation, Captiva Island, Fla.
Series Title: Technical paper - Florida Sea Grant Program
Physical Description: iii, 176 p. : ill., maps ; 28 cm.
Language: English
Creator: Walton, Todd L
Leahy, Thomas M
American Shore and Beach Preservation Association
Florida Shore & Beach Preservation Association
Conference: Beach Seminar, (1978
Publisher: State University System of Florida, Sea Grant Program
Place of Publication: Gainesville
Publication Date: 1978
 Subjects
Subject: Shore protection -- Congresses   ( lcsh )
Beach erosion -- Congresses   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
conference publication   ( marcgt )
non-fiction   ( marcgt )
 Notes
Bibliography: Includes bibliographical references.
Statement of Responsibility: compiled and edited by T.L. Walton, Jr. and T.M. Leahy.
General Note: "Joint annual meeting of American Shore & Beach Preservation Association and Florida Shore & Beach Preservation Association. Co-sponsored by the Coastal Plains Center, Wilmington, NC; Florida Sea Grant Marine Advisory Program, and the Coastal & Oceanographic Engineering Department, University of Florida."
General Note: "October 1978."
Funding: This collection includes items related to Florida’s environments, ecosystems, and species. It includes the subcollections of Florida Cooperative Fish and Wildlife Research Unit project documents, the Florida Sea Grant technical series, the Florida Geological Survey series, the Howard T. Odum Center for Wetland technical reports, and other entities devoted to the study and preservation of Florida's natural resources.
 Record Information
Bibliographic ID: UF00072258
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved, Board of Trustees of the University of Florida
Resource Identifier: aleph - 000990237
notis - AEW7149
oclc - 04741003

Table of Contents
    Front Cover
        Front Cover
    Title Page
        Page i
    Table of Contents
        Page ii
    Program
        Page iii
    The coastal engineering research center's field research facility at Duck, N.C., by Curtis Mason
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
    Emergency beach protection for counties, cities, and towns, by Jon T. Moore
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
    Low cost protective devices for erosion control: An overview of activities of the corps of engineers in the shoreline erosion control demonstration program, by John H. Cousins and John R. Lesnik
        Page 25
        Page 26
        Page 27
        Page 28
        Page 29
        Page 30
        Page 31
        Page 32
        Page 33
        Page 34
        Page 35
        Page 36
    Environmental monitoring of the beach restoration project for the city of Delray Beach, Florida, by Richard H. Spadoni
        Page 37
        Page 38
        Page 39
        Page 40
        Page 41
        Page 42
        Page 43
        Page 44
        Page 45
        Page 46
        Page 47
        Page 48
        Page 49
        Page 50
        Page 51
        Page 52
        Page 53
        Page 54
    Shoreline stabilization and its impact on the receiving waters, by Cherie Down
        Page 55
        Page 56
        Page 57
        Page 58
        Page 59
        Page 60
        Page 61
        Page 62
        Page 63
        Page 64
        Page 65
    Political problems of erosion control, by Lee E. Koppelman and DeWitt S. Davies
        Page 66
        Page 67
        Page 68
        Page 69
        Page 70
        Page 71
        Page 72
        Page 73
        Page 74
        Page 75
        Page 76
        Page 77
        Page 78
        Page 79
        Page 80
        Page 81
        Page 82
        Page 83
        Page 84
        Page 85
        Page 86
    Nature assisted beach enhancement, by Morton Smutz, Mark E. Leadon, John Griffith, and Yu-Hwa Wang
        Page 87
        Page 88
        Page 89
        Page 90
        Page 91
        Page 92
        Page 93
        Page 94
        Page 95
        Page 96
        Page 97
        Page 98
        Page 99
        Page 100
        Page 101
    Rebuilding the beaches of Florida, by Col. James W. R. Adams
        Page 102
        Page 103
        Page 104
        Page 105
        Page 106
        Page 107
        Page 108
        Page 109
        Page 110
        Page 111
        Page 112
        Page 113
        Page 114
        Page 115
        Page 116
        Page 117
        Page 118
        Page 119
    Tidal inlet control of beach erosion - Deposition cycles, by Miles O. Hayes, Duncan M. FitzGerald, and Dennis K. Hubbard
        Page 120
        Page 121
        Page 122
        Page 123
        Page 124
        Page 125
        Page 126
        Page 127
        Page 128
        Page 129
        Page 130
        Page 131
        Page 132
        Page 133
        Page 134
        Page 135
        Page 136
        Page 137
        Page 138
        Page 139
        Page 140
    Beach erosion - Long and short term implications (with special emphasis on the state of Florida), by Todd L. Walton, Jr.
        Page 141
        Page 142
        Page 143
        Page 144
        Page 145
        Page 146
        Page 147
        Page 148
        Page 149
        Page 150
        Page 151
        Page 152
        Page 153
        Page 154
        Page 155
        Page 156
        Page 157
        Page 158
        Page 159
        Page 160
        Page 161
        Page 162
        Page 163
        Page 164
    Addendum
        Page 165
        The coastal plains marine center, by Col. Beverly C. Snow, Jr.
            Page 166
            Page 167
            Page 168
            Page 169
            Page 170
        Beach nourishment in Virginia, by Curtis W. Baskette, Jr.
            Page 171
            Page 172
            Page 173
            Page 174
            Page 175
            Page 176
        Simplified methods for the prediction of hurricane surge and wave runup, by R. Bruce Taylor
            Page 177
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Full Text



~1


PAPERS PRESENTED AT
BEACH SEMINAR '78
October 4 through 7, 1978
South Seas Plantation, Captiva Island, Fla.
Joint annual meeting of American Shore & Beach Preser-
vation Association and Florida Shore & Beach Preser-
vation Association. Co-sponsored by The Coastal Plains
Center, Wilmington, NC; Florida Sea Grant Marine Advisory
Program, and the Coastal & Oceanographic Engineering
Department, University of Florida.
Compiled and Edited by
T. L. Walton, Jr. and T. M. Leahy


Florida Sea Grant


















PAPERS PRESENTED AT
BEACH SEMINAR '78
October 4 through 7, 1978
South Seas Plantation, Captiva Island, Fla.

Joint annual meeting of American Shore & Beach Preser-
vation Association and Florida Shore & Beach Preser-
vation Association. Co-sponsored by The Coastal Plains
Center, Wilmington, NC; Florida Sea Grant Marine Advisory
Program, and the Coastal & Oceanographic Engineering
Department, University of Florida.
Compiled and Edited by
T. L. Walton, Jr. and T. M. Leahy













This Technical Paper was compiled and edited for
Beach Seminar '78 by the Florida Sea Grant College
Program, 2001 McCarty Hall, University of Florida,
Gainesville, FL 32611. Technical papers are duplicated
in limited quantities for specialized audiences
requiring rapid access to information and may receive
only limited editing.







TECHNICAL PAPER NO. 7
October 1978








CONTENTS1


PROGRAM. . . . . . . . .iii

CONTRIBUTED PAPERS AND AUTHORS

The Coastal Engineering Research Center's Field Research
Facility at Duck, N.C. -- Curtis Mason. . . . 1

Emergency Beach Protection for Counties, Cities, and
Towns -- Jon T. Moore . . . . .. 15

Low Cost Protective Devices for Erosion Control an
Overview of Activities of the Corps of Engineers
in the Shoreline Erosion Control Demonstration
Program -- John H. Cousins and John R. Lesnik . . .. 25

Environmental Monitoring of the Beach Restoration Project
for the City of Delray Beach, Florida -- Richard H. Spadoni . 37

Shoreline Stabilization and its Impact on the Receiving
Waters -- Cherie Down . . . . . 55

Political Problems of Erosion Control -- Lee E. Koppelman
and DeWitt S. Davies . . . . . 66

Nature Assisted Beach Enhancement -- Morton Smutz, Mark E.
Leadon, John Griffith, and Yu-Hwa Wang. . . . 87

Rebuilding the Beaches of Florida -- Col. James W. R. Adams . .102

Tidal Inlet Control of Beach Erosion Deposition Cycles
-- Miles 0. Hayes, Duncan M. FitzGerald, and Dennis K. Hubbard. .120

Beach Erosion Long and Short Term Implications (with
special emphasis on the State of Florida) -- Todd L. Walton, Jr.. .141

ADDENDUM

The Coastal Plains Marine Center -- Col. Beverly C. Snow, Jr. ..... .166

Beach Nourishment in Virginia -- Curtis W. Baskette, Jr.. .... .171








Papers not received by press time will be published at a later date

















THE PROGRAM


Wednesday, October 4
9:30 a.m. Board of Directors meeting, ASBPA
9:30 a.m. Board of Directors meeting, FSBPA
1:30 p.m. Opening Session
"Tidal Inlet Control of Beach Erosion -
Deposition Cycles," Dr. Miles Hayes,
Professor of Coastal Processes, University
of South Carolina.
"The Coastal Engineering Research Center's
Field Research Facility in North Carolina,"
Curt Mason, Research Coordinator, CERC
"Investigation of Sinesh Breakwater
Failure (Port Sinesh, Portugal),"
Orville Magoon, Chief, Coastal Engineering
Branch, South Pacific Division, U.S. Army
Corps of Engineers and Dr. Billy Edge,
Department of Civil Engineering, Clemson
University.
6:30 p.m. Welcoming Cocktail Party, sponsored
by South Seas Plantation
Thursday, October 5
8:30 a.m. Second Session
"Storm Effects on Barrier Islands,"
Dr. John Fisher, Associate Professor,
Clemson University.
"The Hurricane Threat to the Shoreline,"
Dr. Neil Frank, Director, National
Hurricane Center, Miami.
"Simplified Methods for the Prediction of
Hurricane Surge and Wave Runup,"
Dr. Bruce Taylor, PE, Tetra Tech, Inc.,
Jacksonville, Fla.
"Emergency Beach Protection for Counties,
Cities and Towns," Jon T. Moore, PE,
Dames & Moore, San Francisco.
12:30 p.m. Luncheon
2:00 p.m. Third Session
"Low Cost Protective Devices for Erosion
Control," Col. John H. Cousins, Director,
Coastal Engineering Research Center, Fort
Belvoir, Va.
"An Alternative to Terminal Groins the
Artificial Offshore Headland," Kris Dane,
PE, Coastal Engineering Consultants, Inc.,
Naples, Fla.
"Nature Assisted Beach Enhancement,"
Dr. Morton Smutz, Associate Director,
Engineering & Industrial Experiment
Station, University of Florida, Gainesville,
Fla.
6:00 p.m. Cocktail party
7:30 p.m. President's Banquet


Friday, October 6
8:30 a.m. Fourth Session
"Beach Erosion in Florida Long and
Short Term Implications," Todd Walton,
Florida Sea Grant Program, Gainesville,
Fla.
"Rebuilding the Beaches of Florida"
Col. James W. R. Adams,
District Engineer, U. S. Army Corps
of Engineers, Jacksonville, Fla.
"Environmental Monitoring Program for
the Delray Beach Nourishment Project,"
Richard H. Spadoni, Ocean Engineer and
Biologist, Arthur V. Strock & Associates,
Inc., Deerfield Beach, Fla.
"State of the Art of Oil Spill
Protection," Lt. Michael Donohoe,
Executive Officer, Gulf Strike Team,
U. S. Coast Guard, NSTL Station,
Mississippi.
12:15 Luncheon
2:00 p.m. Fifth Session
"Shoreline Stabilization," Cherie
Down, County Biologist, Brevard County,
Florida.
"Vegetat'on as a Means of Shoreline
Stabilization and Erosion Control,"
Otto Bundy, President, Horticultural
Systems, Inc. Parrish, Fla. and
Jedrey.Carlton, Biologist, State Marine
Research Laboratory, St. Petersburg,
Fla.
"Political Problems of Erosion Control,"
Dr. Lee Koppelman, Executive Director,
Long Island Regional Planning Board,
Hauppauge, N. Y.
6:30 p.m. Cocktail party
Saturday, October 7
10 a.m. Annual Business Meeting, ASBPA
10 a.m. Annual Business Meeting, FSBPA
Noon Board of Directors Meeting, ASBPA
noon Board of Directors Meeting, -SBPA


*



























THE COASTAL ENGINEERING

RESEARCH CENTER'S

FIELD RESEARCH FACILITY

AT DUCK, N. C.









Curtis Mason
Oceanographer
U.S. Army, Corps of Engineers
Coastal Engineering Research Center
Kingman Building
Fort Belvoir, VA 22060













ABSTRACT


The Coastal Engineering Research Center is building a Field
Research Facility at Duck, N.C., consisting of an 1800 ft long
pier and a laboratory building. The facility is designed to ful-
fill four objectives: 1) to provide a platform for measuring
waves, currents, water levels, and bottom elevations, during
normal and storm conditions; 2) to provide a base of operations
for research studies by CERC and non-CERC investigators; 3) to
provide field data to complement laboratory and analytical stud-
ies and 4) to provide a facility for field testing instrumenta-
tion.

The pier deck, extending from behind the dunes to about the
25 ft water depth, is 20 ft wide, 25 ft above MSL, and is sup-
ported by 3 foot diameter steel pilings. The main building has
4,500 square feet of floor space for offices, a data acquisi-
tion room, a vehicle shelter, and visiting scientists' overnight
accommodations.

Meteorological and oceanographic conditions at the site are
being routinely monitored using wave and tide gages, current
meters, anemometers, and related instruments. Periodic surveys
of the ocean bottom and beaches are also being obtained. Annual
data summaries will be published, and selected short-term data
are available for interested users.

THE COASTAL ENGINEERING RESEARCH CENTER'S
FIELD RESEARCH FACILITY AT DUCK, N.C.


1. Introduction and Purpose

In August, 1977, construction of the 1800 foot long pier
shown in Figure 1 was completed on the Outer Banks of North Caro-
lina, 15 years after the concept of a coastal field research
facility was originally proposed. This paper reviews the back-
ground of this effort; the physical characteristics of the site;
the status of the facility; and related data collection, analysis
and display capabilities. Scientific projects underway and
planned for the facility are also discussed.

The U.S. Army Coastal Engineering Research Center (CERC)
conducts research and development in coastal engineering
to provide a better understanding of coastal processes, winds,














Figure 1. CERC Field Research Facility Pier


LC












waves, tides, currents, and sediments as they apply to navigation,
recreation, storm flood protection, erosion control, and coastal
structures. CERC's mission includes conducting research on the
effects of engineering activities on the ecology of the coastal
zone, as well as collecting and publishing information and data
concerning coastal phenomena and research projects which are use-
ful to the Corps of Engineers, other federal and state agencies,
universities, and the public.

Much of CERC's past coastal engineering research has been
laboratory experimentation and theoretical investigations. Sup-
portive field work has been hampered by the lack of a dependable
means of obtaining high-quality wave, beach, and water level data,
including data during storms. Therefore, the CERC Field Research
Facility has been designed to fulfill four major objectives:

a. To provide a rigid platform from the land, across the
dunes, beach, and surf zone, to the 25 foot water depth, from which
waves, currents, water levels, and bottom elevations can be mea-
sured, especially during severe storms.

b. To serve as a permanent field base of operations for phys-
ical and biological studies of the site, the adjacent sound, and
nearby islands, bays and ocean regions, by CERC and other
agencies and universities.

c. To provide CERC with field experience and data that will
complement laboratory and analytical studies, and provide a better
understanding of the influence of field conditions on measurements
and design practices.

d. To provide a manned field facility for testing of new
instrumentation.

2. Historical Background
The requirement for a field facility to complement CERC's
analytical and laboratory efforts was first recognized in the
early 1960's, and a site on Assateague Island, Maryland, about
100 miles from CERC was selected. However, funding limitations
and problems in obtaining bids for construction delayed selec-
tion of contractors to design and build the pier until 1971.

During the intervening years, the site and adjacent beaches
had become part of the Assateague Island National Seashore, and
when plans for construction of a research facility became public,
objections were raised regarding the environmental and aesthetic
suitability of such a structure in the Seashore. As a result, in
late March 1972, it was decided that the facility would not be










built at Assateague, and a comprehensive study was begun
to select a replacement site somewhere on the U.S. Atlantic or
Gulf coast.

The first step in this effort was to develop a list of
criteria which should be met by proposed sites. In general, the
final criteria required that wave and beach conditions at the
site be representative of U.S. coastal locations; that compli-
cating factors related to the hydrography and shoreline stability
be minimized; and that the site location and size optimize oppor-
tunities to conduct a broad spectrum of coastal studies. Non-
technical criteria specify CERC control of the property, land
access, adequate support, and minimized construction costs. It was
recognized that an ideal site, fulfilling all criteria, might not
be possible, but these gave us a starting point for an evaluation.

Following criteria selection, eleven coastal regions of the
Atlantic and Gulf coasts were ranked according to the extent to
which each region generally satisfied the technical criteria.
Seven of the eleven regions were found to be favorable.

Eleven sites within the seven regions (ranging from Ocean
City, New Jersey to Slidell, Louisiana) were then selected for
specific evaluation following recommendations by federal and
state officials, private citizens, and CERC staff members. The
Outer Banks site near Duck, North Carolina, was finally deter-
mined to best meet the various selection criteria, although it
does not completely meet all of them.

3. Site Description

The coastal plain of North Carolina is a low, partially sub-
merged area varying in width up to 125 miles and confined between
the Piedmont plateau on the west and the continental shelf on the
east. The area contains a series of marine deposits, attesting to
several cycles of emergence and submergence. Formation of the Out-
er Banks barrier island chain along this coast has been compara-
tively recent. The islands are composed of marine deposits of
sand and shell in varying mixtures. The lagoons and sounds inland
of the barriers gradually accumulated sediment derived from erosion
of the adjacent mainland and were converted to marshes, a trend
which presently continues.

Native vegetation of the Outer Banks consists of sea oats
along the dunes, grading landward into thickets typically composed
of wax myrtle, yaupon, willow, grapevines, and other plants, Behind
this outer protective shrub thicket, maritime forests consisting












mainly of pines, cedar, and live oak once covered much of the
islands. However, deforestation for ship timbers and buildings
have reduced these forests to widely scattered patches of woods,
such as those found at the town of Duck.

The Field Research Facility site one mile north of this
town lies on the northern end of Bodie Island between Currituck
Sound and the Atlantic Ocean (See Figure 2). The site is about
1.5 hours by automobile south of Norfolk, VA and about 6 hours south
of Washington, D.C. The nearest airport is a small, non-instru-
mented, paved strip at the Wright Brothers Memorial in Kitty Hawk,
about 10 miles to the south. The property borders 3300 ft of
Atlantic Ocean on the east and Currituck Sound on the west, and is
about 2400 feet wide.

The Duck site was selected because it collectively met the
following eight essential criteria better than other sites evaluated:

a. The site must have a typical size sand beach with sand to
a sufficient depth over differing substrate to prevent exposure of
the underlayer during the expected research life of the pier, which
is 40 years. Sand from the foreshore and surf zone in this region
is quite coarse (median diameter about 0.75mm) and typically bi-
modal. Dune sands are finer, averaging about 0.3 mm median dia-
meter. Offshore, sands decrease in median size from 0.75 mm at the
surf zone to less than 0.1 mm at the 60-ft depth. Indications are
that the surf and foreshore surficial sands form a wedge-shaped
cross section which pinches out on top of finer sands just seaward
of the surf zone. The composite thickness of alternating layers
of 1 and 0.3 mm material on the foreshore is at least 6 feet. No
consolidated subsurface strata were observed to crop out and none
was indicated on well logs available from local developers. Surficial
beach sand at the site is considerably larger than the 0.15 to 0.5 mm
considered typical of U.S. beaches.

b. The site must have exposure to a wave climate, including
storm occurrence and wave directions, that is representative of
U.S. coasts. A summary of weather features affecting Cape Hatteras,
65 miles south, indicates that the sky should be clear at Duck about
100 days per year, and that the annual rainfall of 55 inches will
be evenly distributed throughout the year. Mean daily temperatures
range from 780 during July and August to 530 in January and
February. Mean monthly wind speeds of about 12 miles per hour

























































Figure 2. Location Map.








7













prevail from the northeast between September and February, and from
the southwest the remainder of the year. Because of this wind pat-
tern, waves generally approach the Duck site from the northeast
during the winter and from the east and southeast during the sum-
mer. This bi-directional wave climate is representative of many
U.S. coastal locations. Data from a wave gage at Nags Head, 13
miles south, show the mean annual significant wave height to be
about 1 meter, with a standard deviation of 0.7 meters. The mean
significant wave period is about 8 seconds, with a 2.5 second stan-
dard deviation. Longshore sediment transport rates are estimated
to be about 1.5 million cubic yards per year southward, and about
750,000 cubic yards per year northward, for a 2:1 southward pre-
dominance, due primarily to the effects of winter storms (north-
easters). Over the past 70 years, hurricanes have affected the
area to some extent about once every two years.

c. The site must have a significant astronomical tide (i.e.,
range on the order of 0.5 to 2 meters). Ocean tides at the site
are semi-diurnal, with a spring range of about 1.5 meters and a
neap range of about 0.7 meters. Water levels in Currituck Sound
are wind-dominated: high during periods of southwest winds, and
low when winds are from the northeast.

d. The nearshore slope must be representative of sandy U.S.
coasts, and such that the 20-ft-depth contour is not appreciably
more than 2000 ft from the mean sea level intercept. The nearshore
slope is reasonably typical of other U.S. coastal profiles, and
the 20 ft contour is about 1000 ft from the mean sea level contour.

e. The site must be located on a straight coastline outside the
range of effects of any significant littoral barrier. The coast-
line is relatively straight, curving gently to the east south of
the site, and with an indentation about 3.5 miles north at the
location of a former inlet. No inlets or structures exist on the
coast within 5 miles of the site.

f. The site must be free of offshore bottom features which may
lead to severe anomalies in the wave climate in the nearshore area.
Hydrographic charts show that no unusual offshore bottom features
exist in the immediate vicinity of the pier, but that waves
approaching from the northeast may be refracted by shoals near
False Cape.

g. The site must be accessible by land vehicles. A paved
state highway is connected to the site by a crushed gravel road.










h. CERC must have control of the use of the pier and
adjacent beaches to ensure lack of interference with research
programs. Although visitors are allowed at the site, public access
to the pier is restricted. The pier ramp and all shore facilities
are surrounded by a chain link fence which is locked during non-
working hours. Ramps at the north and south edges of the pro-
perty allow beach vehicles to transit from the beach, over the
dunes and around the facility so that on-going beach studies will
not be affected.

Secondary criteria which were felt to be desirable were also
met by the Duck site. These relate to site size and proximity to
other study areas and to CERC, availability of power and tele-
phone lines, presence of natural dunes, generally good weather
conditions and relatively stable shorelines.

4. Facilities
The physical characteristics of the major structures of the
Field Research Facility, the main building and the research pier,
are as follows: The 4600-sq.-ft laboratory building of the Facil-
ity will have four rooms for data collection and preliminary analy-
sis efforts, an instrument repair shop, a vehicle shelter, a diving
locker, and a two-bedroom living area with kitchen. This building
will be 90 ft long parallel to the ocean, 51 ft deep, and about
21 ft high. A platform for outside work and access to the pier
will surround the building. The research pier is a reinforced con-
crete structure supported with 3 feet diameter steel piles spaced
40 ft apart along the pier length and 15 ft below the ocean bottom.
The pier deck is 20 ft wide and extends 1840 ft from behind the
dune line to about the 25-ft water depth. The deck is 25 ft above
mean sea level. Concrete erosion collars protect the steel pilings
against sand abrasion, and a cathodic protection system protects
the steel pilings against corrosion. Railroad rails set 10 ft cen-
ter to center run the full length of the pier and can support a
16-ton load. The safe load between the rails is limited to a
vehicle such as a pickup truck with a maximum wheel load of 2000
lbs. The electrical power outlets are presently 120 volts, 20
amperes and 240 volts, 30 amperes but these will be increased to a
total of 200 amps. Outlets are spaced in sets along the pier
approximately 40 ft apart. Two telephone stations are to be installed
on the pier, one at the seaward end and one about mid-point.












A basic environmental measurements program has been estab-
lished to routinely measure, record, and publish data on the
meteorological and oceanographic conditions at the site. Following
data collection and editing, certain routine analyses are made.
The data and results are made available to other CERC studies
and to the scientific and engineering community upon request by the
CERC Coastal Engineering Information and Analysis Center. Annual
inhouse reports summarizing the data acquired during the previous
year and describing related aspects of data collection, analysis,
and storage will be prepared.

Meteorological data presently being collected on pen and ink
records from a National Weather Service onshore climatological
station are wind speed and direction, barometric pressure,
accumulated precipitation, total solar radiation, and air temper-
ature and relative humidity. An anemometer linked directly to NWS
headquarters will also be installed on the pier about 1000' off-
shore. Visual observations of related weather conditions and
checks of the recording instrumentation are made once a day.

Tide data are collected by National Ocean Survey (NOS) tide
gages at the pier end and at about the 8-ft water depth. Paper tape
is punched at six minute intervals giving the time and instanta-
neous water level reading. The data are reduced by the Tides Branch
at NOS, and data records and summaries are routinely forwarded to
CERC. A CERC tide gage gives an analog record of water levels in
the sound just behind the site.

Daily ocean water temperature and salinity measurements are
made at the seaward end of the pier, three feet above the bottom
and six feet below MSL.

To measure changes in the beaches and ocean bottom, weekly
lead-line soundings on each side of the pier are being made, as
are pre- and post-storm profiles.

Quarterly surveys from behind the dunes to the -40 foot
contour and extending a mile north and south of the pier are also
conducted.

Aerial photographs of the coastline from Cape Hatteras to
Cape Henry, with a perpendicular flight at the Facility, are being
flown quarterly and after major storms. The multi-spectral imagery
employed include black and white, color, color infrared exposed for
land and color infrared exposed for water.










Wave data are obtained from two Baylor-type gages, suspended
on the pier centerline, one at the pier end and one in about 8 feet
of water, and from one pressure transducer at the pier end. In
addition, a wave rider buoy is anchored near the pier's seaward end,
with a second one approximately 1-1/2 miles offshore. A wave gage
at Nags Head will continue to operate for about one year, or until
such time as a relationship between the wave characteristics at
both sites can be established. Visual observations of wave height,
period, and direction are also taken twice a day from the pier.

Wave and ocean currents are measured by two x-y electromagnetic
current meters positioned two feet above the bottom. One of these
meters is at the seaward end of the pier, and the other is at the
same depth but 500 feet north, to assess the effect of the pier on
currents.

At present, wave and current data are transmitted by leased
telephone line to CERC and recorded on magnetic tape by the CERC
Data Acquisition System. The data are sampled four times a second
for twenty minutes, four times per day. The present system pro-
vides two non-overlapping sequences of 4 channels each. An addi-
tional 4 channels could be added for other observations in the same
format. An expanded data acquisition system is presently being
designed for the Facility. However, it will primarily be for CERC
field studies, and outside users should plan to provide their own
data acquisition systems.

One important item is the policy of assessing costs to the out-
side user. If a project is proposed that is directly applicable to
CERC's mission in coastal engineering research, free use of the pier
will be offered, as will limited support by on-site CERC personnel.
CERC data from the basic environmental measurements program will also
be furnished free of charge. Costs for extensive use of pier
personnel and for projects not related to CERC's mission will be
assessed at a rate dependent upon the degree of public interest
served and the user's financial resources. Work priorities for the
on-site CERC personnel are established by the Research Coordinator,
subject to the concurrence of the Technical Director.

5. Existing and proposed studies

The studies classified as desirable are those we feel should be
done either by CERC at some later date, or sooner by interested out-
side users. Although CERC funding limitations preclude direct support
for these studies, we would endorse attempts by qualified investigators
to obtain funding from other sources.













Prior to initiation of pier construction, a complete topo-
graphic survey was made of the beaches and dunes, and a hydro-
graphic survey was made of the adjacent ocean bottom. Borings were
made to a depth of 70 feet below sea level and a geophysical survey
was conducted to establish the geologic and engineering subsur-
face conditions in the pier construction area.

A beach profiling study was also initiated before pier
construction, and these profiles continue to be monitored to
assess the effect of the pier on the adjacent beaches.

Baseline studies of the native flora and fauna of the island
and nearshore zones have been made, and study results will be used
to evaluate the ecological effects of pier construction and site
habitation. Experimental marshes have been planted on the edge
of Currituck Sound to evaluate the use of vegetation in preventing
or minimizing shore erosion. As part of this effort, a tide gage
was installed in the sound in September 1973 which has provided
useful information on the characteristics of water level fluctu-
ations.

Research studies presently underway or planned for the next 3
years and those which are desirable are grouped into five areas:
Nearshore Wave Transformation, Nearshore Sediment Transport, Coastal
Ecology, Remote Sensing, and Supplemental.

In the Nearshore Wave Transformation subprogram, recent CERC
field studies have shown radar to be a promising tool to measure
wave direction. This concept will be further evaluated at the
Field Research Facility within the coming year in conjunction with
an evaluation of sensors aboard the SEASAT-A satellite.

A CERC study is underway to measure the transformation of
waves as they enter shallow water and break. Five Baylor wave
gages have been installed to define the shore-normal changes in
wave characteristics. A related research effort involves the pre-
diction of wave transformation from deep water areas to the breaker
zone. Data from the offshore wave gage and aerial photographs will
be used to improve refraction and shoaling models.

An analysis to assess the relative contributions of sea
and swell, wind, and tides on the nearshore current regime
is planned which will be supplemented by empirical data from
measurements at the Facility.

The wind-driven component of coastal currents has been stud-
ied by a graduate student from Old Dominion University.









Wave run-up will be measured at the site to supplement
laboratory data collected in an ongoing wave run-up and over-
topping study.

Offshore and nearshore wave data from the FRF will be used
in an investigation to define sources of wave reflection and
attenuation. Several additional studies in Nearshore Wave
Transformation are desirable. Although CERC funds are not pres-
ently available for these, we believe they merit support from other
agencies. These include wave set-up on beaches, water level changes
across the surf zone, wave transformation and reflection on submarine
bars, wind effects on breaking waves, long period waves in the near-
shore zone, internal waves, standing waves in shore-normal direction,
edge waves, and wave/current interaction.

In the Nearshore Sediment Transport subprogram, field measure-
ments are being made at a number of coastal locations, including
the FRF, just before and after coastal storms. These, together
with data on winds, waves, and water levels, will be used to estab-
lish relationships between beach erosion and storm intensity.

The state-of-the-art of measuring longshore sediment transport
rates will be assessed, and the two most promising techniques will
be applied at the FRF.

Later stages of a seaward limit of effective sediment trans-
port study will involve field determinations of such a limit, and
the Facility will provide supportive data for this study.


The objectives of the Nearshore Placement of Sediment for
Beach Nourishment Study are to examine changes in profile shape
and sediment distribution along the nearshore profile in rela-
tion to winds, waves and currents, and to provide guidelines for
placing sand in the nearshore zone for beach nourishment purposes.
Much of the field work for this study will be done at the site.

Little is known about shore response to offshore dredging.
Therefore, guidelines are being developed for determining the
optimum distance from shore, the shape, and the water depth of a
dredged hole, such that it will not adversely affect the shore.
Plans call for qualitatively determining the rate of sediment
transport at various locations in the nearshore zone at the site,
and to quantify the processes controlling these rates.












The following Nearshore Sediment Transport studies at the
Facility are desirable: wind blown sediment transport; time scale
of beach response; response of nearshore bottom to storms; barrier
island migration; occurrence and stability of various sand sizes on
beach profile; develop low cost seismic reflection technology for
surf zone; effect of temperature on field sediment transport;
evaluate movable bed model technology; and sediment budget for
the FRF.

In the coastal ecology subprogram, CERC studies concern use of
vegetation for bank erosion control in Currituck Sound, and assess-
ing the effects of pier construction on the environment.

In remote sensing, a SEASAT-A evaluation is being conducted
by CERC and many other agencies. Data from instruments located
on the satellite and aboard airplanes will be compared with ground
truth data from sensors on the pier and with various radars under
development by CERC, the Naval Research Laboratory and NASA. An
evaluation of the state-of-the-art of remote sensing techniques
for coastal engineering may utilize the pier site to meet its
objectives.

The final group of supplemental studies are those which do
not readily fall into the previous groups. The basic environmental
measurements program and North Carolina inlet research are two
inhouse efforts. The others are less directly connected with the
CERC program, and therefore are proposed for outside funding. These
include studies of the tidal characteristics of ocean and sound, wind
characteristics and changes near the shoreline, temperature and
salinity characteristics of ocean and sound, solar radiation
characteristics, and sea/air interaction.

6. Summary.

The purpose and capabilities of the Field Research Facility
have been reviewed, and the research program outlined. CERC
encourages the use of the facility by outside investigators, for
we feel it offers a unique opportunity to study coastal phenomena
during both normal and storm conditions.

ACKNOWLEDGEMENT

This paper was prepared under the Coastal Engineering Research
program of the U.S. Army Corps of Engineers.




























EMERGENCY BEACH PROTECTION FOR

COUNTIES, CITIES, AND TOWNS













Jon T. Moore
Project Engineer
Dames & Moore
500 Sansome Street
San Francisco, CA 94111














ABSTRACT

Coastal erosion management has not directed much attention

to emergency beach protection methods. The extent of private
shoreline ownership in the country exempts many developed areas of
the coastal zone from public assistance. Consequently,
implementation of protection measures to combat storm erosion
events are generally ill conceived and plagued by a confusion of
who is responsible for coping with the problem. This paper
suggests that erosion contingency plans be authorized to develop,
with multidisciplinary input, preselected plans of action to handle
future erosion events. In this manner, intelligent management
decisions can be made as to appropriate storm erosion mitigation
measures to adopt thereby contributing to a most efficient program
of action.


INTRODUCTION

Storm related erosion is an ever present threat to coastal

structures located in vulnerable backshore regions. The gradual
rise in sea level has perhaps aggravated the problem in recent
years, but it is coastal storms coincident with high tides which
cause the worst damage. Traditionally, shoreline erosion is dealt
with by long term mitigation measures such as beach nourishment
programs to replenish lost materials or coastal structures such as
seawalls to cease further encroachment landward. Coastal storm
erosion is often concentrated within relatively short periods of
time which implies that emergency measures to arrest a particular
storm events) may be feasible in protecting property from damage.
By investigating the coastal processes of a region and projecting
the return period of probable erosion events, a systematic program













of appropriate action could be adopted ahead to time to protect
threatened structures. Decisions concerning the emergency
mobilization of materials and labor could be pre-established such
that the most feasible and practical utilization of funds and
effort would be expended corresponding to the severity of the storm
event.

The need for such a planning program is evident from the
extent of coastal erosion in the United States, as about one-forth
of the nation's shoreline is significantly affected by erosion.
The Corps of Engineers has reported in its National Shoreline
Inventory that critical erosion occurs along 2700 miles of
coastline (1). Located mainly on heavily populated Atlantic and
Great Lakes shores, the problem is caused by a combination of
natural and man-induced factors such that shoreline recessions of
less than one foot per year may be destructive. Not all areas are
equally threatened since the significance of the erosion depends
upon the population of the coastline. Consequently, areas in the
Pacific Northwest, Alaska, and Hawaii suffer the least social and
economic loss from erosion. More than 75 percent of the country's
total citizens resides in the coastal states, and growth estimates
indicate population within one mile of shorefront areas has been
increasing at more than three times the national rate (2). Average
annual losses due to erosion are high and stems mostly from damage
to private homes, beaches, and shore protection structures. As the
shoreline continues to attract industry, offshore continental shelf
support activities, power plants, and second home owners and
retirees, the damage costs are certain to increase (3).

Approximately 70 percent of shoreline lands are privately
owned and herein lies the dilemma and controversy. This ownership
criteria disqualifies the property from receiving public assistance











for shoreline protection, and this often results in privately
coordinated erosion protection schemes that are ill conceived and
aggravate the situation (4). There is generally no clearly
established responsibility or program available to cope with
erosion events, and panic can prevail to compound and delay
mitigating the desperate situation.

The author suggests that multidisciplinary contingency
planning for future erosion events may be a prudent policy to
enact. The coastal engineer, environmentalist, economist, and
regulatory official could, with geographic specificity, analyze the
particular characteristics of a coastal region, determine what
storm erosion mitigation measures could be utilized, and establish
the financial and managerial responsibility for their implemen-
tation. In this manner, the very least the property owner would
receive, would be a document clearly describing the risk he assumes
at his property and the acceptable and specific steps he could take
to combat a storm erosion event.


EROSION MECHANISM

The severity of beach erosion is generally attributed to the
degree and duration of short period wave attack on the beach in
conjunction with the stillwater level (astronomical tide level plus
wind tide or storm surge). A schematic diagram illustrating the
process may be seen in figure 1-7 of Reference 5 which basically
shows the removal of the protective beach berm to an offshore bar
thereby exposing the backshore areas to erosion. Domurant and
Moore summarized in their respective papers the characteristics and
affects of a series of severe winter storms which impacted on the
California coastline in 1978 (6,7). In general the erosion
progressed from erosion of the beach berm sands to exposure of













backshore areas which were commonly attacked in a toe undermining
process. This type of erosion is feasible to arrest and has been
successfully accomplished in California.

The intensity of the storm and the degree of storm surge
governs the practical limits of protection of coastal structures.
As an extreme upper limit, the coastal storm of March 1962 which
devastated Fire Island, New York was so overwhelming that no
emergency methods could have been economically or feasibally
mobilized to combat the situation. Review of record storm surges,
storm erosion, and damage for several east coast areas (8) also
implies that little short term measures could be enacted to combat
the severe event, but a statistical evaluation of the probable
return periods for less intense storms may conclude that emergency
measures would be economically viable. Furthermore, the general
characteristics of the beach profile before and after a Class 3
hurricane in Florida indicates that toe erosion was a typical
mechanism of shoreline retreat (9), and that it may have been
feasible to mitigate recession had coastal structures been
threatened.


EMERGENCY BEACH PROTECTION METHODS

Edge et al have summarized the current devices and methods
that have been proposed for low-cost shoreline protection (10).
These methods were specifically addressed for demonstration in
sheltered waters (wave height less than 6 feet at coastal shores)
and represent the variety of alternatives available to resist
erosion until long period waves begin to restore the depleted
shoreline. From an emergency mobilization standpoint, feasible
methods would probably be limited to a form of revetment or
seawall. Graded rock riprap is the most common material that can











be placed, and if properly sized, can resist storm erosion. Other
means such as longard sand-filled tubes have been effective in
arresting dune erosion.

Under a storm erosion event, one can be limited to workable
conditions only during time of low water since the presence of
structures and soil stability criteria may preclude the necessary
heavy construction equipment from the bluff top. Therefore,
depending on the specific site conditions, the particular method of
erosion protection will be limited to its availability and
placement time. At Stinson Beach, California, a combination of
longard sand-filled tubes and rock riprap was placed over a 5 day
period to protect 600 feet of severely threatened homesites (11).
Had a specific plan of action been thought out prior to the winter
storms, a more timely and less costly program of action could have
been carried out with the same success.


EMERGENCY EROSION CONTINGENCY PLANNING

The basic concept of emergency erosion contingency planning
(ECP) is patterned after that already adopted for spills of oil or
hazardous substances. The specific area in question is analyzed
for its particular characteristics and carefully thought out
mitigation measures and decision points are preplanned for
implementation as the situation warrents. Thus, in the case of
coastal erosion, the characteristics of a shore are appraised,
feasible protection methods preselected, cost-benefit analysis and
environmental consequences evaluated, and a detailed plan of action
formulated outlining the series of steps to be followed.













Such plans could be incorporated as part of the shoreline
erosion elements of state and local coastal programs. At present,
there is generally no recourse available to the private property
owner to address the situation until it is too late. The Federal
Insurance Administrative has labored hard over the question of
equitable insurance programs for coastal zone flood damage (12),
and has encountered difficulty in establishing proper set back
distance criteria and insurance rate concept so that the property
owner might insure his structure against probable loss. The ECP
would perhaps help in clearing this question by offering an
alternative method of approach via its study results. The ECP
would address itself to the specific behavior of a coastal area
with an estimated probability of events that could occur together
with the degree of feasible methods, if any, that might protect the
property during the storm period. By evaluating the cost-benefits
of the area and its protection plan, the regulatory official can
then make intelligent decisions regarding the worthiness of
government sponsorship to underwrite the developed shore.

The basic steps of an ECP would be as follows:
1. Document the area's shore erosion history
2. Statistically determine return periods of coastal storms
3. Formulate most probable scenarios of light, moderate,
and severe storm erosion
4. Analyze and determine most feasible emergency measures
to combat storm erosion.
5. Conduct cost-benefit analysis to compare construction
costs with socioeconomic benefits to be derived.














6. Prepare detailed ECP with step by step procedural plan
of action for implementation of various levels of
emergency action corresponding to storm intensity.
7. Adopt level of government sponsorship, i.e. the degree
of funds to be appropriated and support to be offered.

Formulation of ECP's requires the bringing together of
various disciplines to address the task. Coastal engineers will be
called upon to stretch state-of-the-art technology in making
decisions regarding erosion prediction and mitigation. Economists
and insurance adjusters will be needed to evaluate and compare the
different levels of emergency action in terms of benefits gained.
Environmentalists will need to comment on the different
alternatives proposed for action so that the quality of the
shoreline is not damaged. Finally, the regulatory official will
need to adopt the appropriate legal action to enact an equitable
program that once and for all lets the property owner know exactly
where he stands.

The extremes of policy procedure are as follows:
1. Full government construction funding of emergency
protection measures.
2. Non-intervention and zero funding, but sponsorship of
the preparation of the ECP offered for private
implementation.
It is likely that the final program would fall somewhere between 1
and 2. In the opinion of the author, all the components are
available to make reasonable professional estimates, and therefore
it would be appropriate to adopt ECP's for the nation's shoreline.
As a result, it may be concluded that emergency measures, feasible
at one location, are totally useless at another, therefore leading
to long term measures as the only adoptable means of coastal





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LIST OF REFERENCES

1. US Army Corps of Engineers, "Report on the National Shoreline
Study." U.S. Govt. Printing Office, Washington D.C., 1971.

2. Sorensen, John H., and J. Kenneth Mitchell, "Coastal Erosion Hazard
in the United States, a Research Assessment", Institue of
Behavioral Science, The University of Colorado, 1975.

3. US Department of Commerce, "Natural Hazard Management in Coastal
Areas", Institute of Behavioral Science, The University of
Colorado, November 1976.

4. Mitchell, James K., "Issues Involved in United States Beach
Preservation and Protection Programs", Paper based on address
delivered at the Panel on Beach Preservation and Protection,
Marine Technology Society 10th Annual Conference,
Washington D.C., Sept. 23-25, 1974.

5. US Army Corps of Engineers, "Shore Protection Manual", US Army
Coastal Engineering Research Center, 1975.

6. Dormurat, George W., "Selected Coastal Storm Damage in California,
Winter of 1977-78", Shore & Beach Vol. 46, No. 3, July 1978.

7. Moore, Jon T., "Emergency Erosion Protection and Contingency
Planning", Ibid.

8. Burton, lan, and Robert Kates and Rodman Snead, "The Human Ecology
of Coastal Flood Hazard in Megalopolis", Department of Geology,
University of Chicago, 1969.

9. Chiu, T.Y., "Beach and Dune Response to Hurricane Eloise of
September 1975", Proceedings of Coastal Sediments 77, ASCE,
November 1977.

10. Edge, Billy L. and John G. Housley and George M. Watts, "Low-Cost
Shoreline Protection", Proceedings of the 15th Coastal
Engineering Conference, ASCE, July 1976.

11. Moore, Jon T., "Emergency Protection of Eroding Shores, "Proceedings
of Coastal Zone 78, ASCE, March 1978.

12. Department of Housing and Urban Development, "Proceedings of the
National Conference on Coastal Erosion", Federal Insurance
Administration, July 1977.


























LOW COST PROTECTIVE DEVICES


FOR EROSION CONTROL

AN OVERVIEW OF ACTIVITIES.

OF THE CORPS

OF ENGINEERS IN THE SHORELINE EROSION

CONTROL DEMONSTRATION PROGRAM







John H. Cousins
Colonel, Corps of Engineers
Director, U.S. Army
Coastal Engineering Research Center
Fort Belvoir, VA

and

John R. Lesnik
Hydraulic Engineer, U.S. Army
Coastal Engineering Research Center
Fort Belvoir, VA










LOW COST PROTECTIVE DEVICES FOR EROSION CONTROL
An Overview of Activities of the Corps of Engineers
In The Shoreline Erosion Control Demonstration Program
by

John H. Cousins*
John R. Lesnik*


ABSTRACT

The pressures of increased recreational use and development
of the shorelines has led to public demands for effective shore-
line erosion control. Federal involvement in this problem began
in 1930 with the formation of the Beach Erosion Board. This
involvement has expanded through the years as evidenced by the
Shoreline Erosion Control Demonstration Act of 1974. This Act
appropriated $8 million to be spent over 5 years in demonstrating
means of "low-cost" shore protection (including vegetation) in
sheltered waters. The Act also authorized the formation of a
Shoreline Erosion Advisory Panel to assist the Chief of Engineers
in carrying out this program. With the assistance of this
15-member panel, the Chief of Engineers approved demonstration
projects at 15 sites on the coastlines of the Delaware Bay, the
Atlantic, the Gulf of Mexico, the Pacific, Alaska, and the Great
Lakes. Six of the sites are located on Delaware Bay (as required
by the legislation) and the remaining coastlines will each have
two. One site remains to be chosen for the Atlantic which will
make a total of 16 demonstration sites. These sites are described
briefly with emphasis given to noteworthy devices which are being
demonstrated. Construction should be complete at 14 sites by the
end of this year and all 16 sites should be finished by the sum-
mer of 1979. If enough funds remain, approximately 20 additional.
sites with existing shore protection devices (constructed by
others) will be monitored to gather additional data.

INTRODUCTION

Increased development and usage of our coastlines for
recreational purposes, which began early in this century, spawned
a continuing public demand for shoreline erosion control. The
formation and long distinguished history of the ASBPA testifies
of this interest in beach erosion control.



*Colonel, Corps of Engineers, Director, U.S. Army, Coastal
Engineering Research Center, Fort Belvoir, Va.
*Hydraulic Engineer, U.S. Army, Coastal Engineering Research
Center, Fort Belvoir, Va.












FEDERAL INVOLVEMENT IN BEACH EROSION CONTROL


The early history of Federal involvement in beach erosion
control began in 1930 with the establishment of the Beach Erosion
Board. The function of the Board however, was limited to studying
beach erosion problems; the Federal government was not yet in-
volved in construction. In 1936, Congress granted authority for
Federal participation in construction, but only where Federal
lands or investments required protection.

Federal participation in beach erosion projects was author-
ized in 1946. The Federal share of the costs however, was limited
to one-third of the total. This was later changed, in 1965, to
50 percent; 70 percent if public parks or conservation areas are
involved. Also, in 1963, the Beach Erosion Board was replaced by
the Coastal Engineering Research Center and authorization was
given for the formation of the Coastal Engineering Research Board.

The Federal government therefore, has been relatively slow
in stepping into the problem of beach erosion; at least in funding
construction of mitigation measures. A critical problem which
still remains is that the erosion which is most conspicuous occurs
along highly developed shorelines, and most of these are privately
owned.

Briefly consider the damages which occurred on the east coast
as a result of the February storm this year. For instance, Dune-
wood, which was typical of much of Long Island, suffered severe
beach erosion and a prominent scarp was formed. The Scituate-
Marshfield area in Massachusetts also suffered severe and exten-
sive damage.

Congressman Jack Kemp of New York has been a supporter of
Federal involvement in shoreline erosion control. In a statement
to the Congress on 20 May 1976 when he introduced legislation to
allow tax deductions for losses from shoreline erosion, he noted:
".... the experiences of the past several years have convinced me
that anything more than a minimally acceptable Federal commitment
to shoreline erosion damage relief is unlikely in the near fu-
ture." and, ".... Federal progress in controlling beach and shore-
line erosion has been slow. Of a total of 64 projects authorized
since 1946 on the Federal level, only 20 have been completed. The
average time to complete the 20 projects or project segments has
been about 10 years from the date of the local request."










Two Federal beach erosion control projects typify recent
Corps involvement in beach erosion control. At Lakeview Park,
Lorain, Ohio, three segmented, detached breakwaters were con-
structed to stabilize and retain a beachfill behind them. Project
costs were $1.4 million. One year of monitoring has shown that
the beach has been effectively stabilized.

Rockaway Beach, New York is primarily a beach fill project
with periodic renourishment required, particularly after major
storms. For a beach fill project such as this one which cost
$14 million, critics often complain about the great amount of
sand, hence money, which can be washed away by one major storm.
The only response is, "What would have happened if the project
had not been built?" The presence of the beach prevented what
may have been extensive damage to back shore developments.
Because of the high monetary value of those developments, this
damage could easily have approached several million dollars.

THE SHORELINE EROSION CONTROL DEMONSTRATION ACT OF 1974

The private landowner cannot normally afford such protective
projects, and even if he could, his small section of shoreline
might not lend itself to such measures. In response to this
need, Congress passed the Shoreline Erosion Control Demonstration
Act of 1974. This Act is Section 54 of the 1974 Water Resources
Development Act. The program operates for 5 years with total
funding equaling $8,000,000. Recognizing that "low cost" pro-
tection was not consistent with the requirements on the open
coast, Congress emphasized control on sheltered or inland waters.
In that light, the use of vegetation (as well as structures) was
specified as an erosion control device. This led to the require-
ment that the Corps cooperate with the Department of Agriculture
on plans for utilizing vegetation.

The program permits construction on private or public lands
if the non-Federal sponsor will contribute 25 percent of the
initial construction costs. This requirement has caused problems
at several sites which were subsequently dropped from the program
for that reason. The local sponsors must also assume operation
and maintenance responsibility upon termination of the study. No
Federal funds can be used for land acquisition.

A significant aspect of this legislation was the formation
of the Shoreline Erosion Advisory Panel. Its general purpose is
to advise the Chief of Engineers on how to best implement the












Section 54 program. This would include recommendations on site
selection criteria and procedures needed to secure the coopera-
tion of non-Federal sponsors. The panel is also required to per-
form periodic progress reviews as well as recommend ways to best
disseminate the results of the study to the public. Throughout
the course of the program it may also be called upon to perform
other duties in support of the Chief of Engineers.

The panel consists of 15 members who are not employed by the
Corps. They were chosen to represent a broad spectrum of geo-
graphic areas and fields of expertise. Mr. Joseph Caldwell, the
Panel Chairman, is the former Chief of Engineering at the Office
of the Chief of Engineers.

Because of the size of the Panel, it was broken into
Committees. The Committees sought the advice of the Corps'
District Engineers, the States, and other personal contacts to
identify erosion problems that might be typical of the various
regions. At Panel meetings, several companies and private indi-
viduals gave presentations on concepts, materials, and inventions
for controlling erosion. Many of these devices were included in
the demonstration program as will be discussed later.

The Panel was also subdivided into working groups for each
of the coastlines of the Atlantic, Pacific, Gulf of Mexico and
Great Lakes. These working groups visited many sites which were
recommended by various sources and reported their observations
to the full Panel. The Panel in turn, recommended possible sites
to the Chief of Engineers.

The site selection criteria involve legal, social, environ-
mental and economic considerations. The legal criteria must
obviously be met, a principal consideration being that the site
is on sheltered or inland waters. This means that the waves
breaking on the shores have been limited by natural conditions to
a significant height that does not preclude the use of low cost
protective measures. The Panel generally considered waves of
about 6 feet or less as being acceptable, but a specific height
criterion was avoided. Also, the law specified a minimum of two
sites per coastal region including Alaska.

The social or public relations criteria was primarily con-
cerned with accessibility to the public. If erosion protection
is being demonstrated, the public must be able to visit and ob-
serve the project throughout its life.










Environmental considerations include such things as: Is the
site representative of a large number of areas facing coastal
erosion in a region?

The economic criteria address the use of low-cost protection
methods. The Panel has defined "low-cost" as $50 per foot of pro-
tection for materials, if no heavy equipment is required and $125
per foot, for materials and placement with heavy equipment. The
protection is designed for a 10-year life with only minimum
maintenance required provided no storm occurs with a recurrence
interval greater than 25 years. The cost figures used are mid-
1975 levels and the Panel has found it difficult to keep project
costs within these limits.

DEMONSTRATION SITES

The Chief of Engineers, based on recommendations of the
Panel, has chosen 16 sites, nationwide, for demonstration projects.
There are six sites in Delaware Bay and two each on the coastlines
of the Atlantic, Gulf of Mexico, Pacific, Great Lakes and Alaska.
The six sites in Delaware Bay reflect the influence of a local
Congressman who was instrumental in getting the legislation
enacted. They are the only sites specifically identified by the
Act for inclusion in the program. The remaining ten sites are
distributed, two each, around the remaining coastal regions.

DELAWARE BAY SITES

The six Delaware Bay sites are Bowers, Broadkill Beach,
Lewes, Pickering Beach, Slaughter Beach and Kitts Hummock, all in
Delaware. Bowers, Broadkill Beach, and Lewes are already pro-
tected by Federal or State erosion control projects and therefore,
will not receive additional erosion control devices as part of
this program. These existing projects will be monitored during
this study.

Pickering Beach, Delaware

The planned demonstration at Pickering Beach will be a
floating, rubber-tire breakwater. Two different designs will be
tested. The Type I design will be a "Wave Maze" and the Type II
will be a "Goodyear" design. Different breakwater widths are
being tested in an attempt to determine how their wave transmission
characteristics vary.












The structures will be anchored with concrete blocks about
1100 feet from shore. The depth at the structures will be approx-
imately 6 feet at MHW. The tires in the Goodyear modules will be.
bound with conveyor belt edging which will then be fastened with
nylon bolts and nuts. Foam is used for flotation.

In the "Wave Maze" module the individual tires are bolted
together and the planform of the completed breakwater is a
parallelogram.

Kitts Hummock, Delaware

At Kitts Hummock, a series of three detached breakwaters are
planned. One structure will be conventional rubble-mound, one
will be sand-filled bags and the third will be constructed with
a row of large, precast, rectangular concrete manhole sections,
ballasted with sand. The structures will average about 700 feet
from shore and they will be submerged at MHW. The sand bag
structure will employ filter cloth and the rubble structure will
rest partly on filter cloth and partly on graded stone.

Slaughter Beach, Delaware

A perched beach will be demonstrated at Slaughter Beach.
The sill will be constructed with a segment of sand-filled bags,
one of wood sheetpiling and a third of rectangular concrete man-
hole sections ballasted with sand. The crest elevation of this
sill will be at MLW and the beach will be an artificial fill
rather than the product of natural accretion. The sand bags will
only be one bag high and they will be placed on filter cloth.

ATLANTIC COAST SITES

Fort Raleigh, North Carolina

Bull Island, South Carolina was originally planned as one of
the Atlantic Coast sites. The Department of Interior however,
withdrew their support of the project because of objections which
arose concerning the placement of structures on an undeveloped
barrier island. A search for an alternate site was then neces-
sary. Fort Raleigh, North Carolina, on Roanoke Island, is now
tentatively planned as a replacement demonstration site. No
specific plans have yet been reviewed by the full Panel however.










Jensen-Stuart Causeways, Florida


The other Atlantic coast site is at the Jensen-Stuart Cause-
ways, between Fort Pierce and West Palm Beach, Florida. There are
a number of test sites for this project located on the north and
south sides of the two causeways connecting Hutchinson Island with
Jensen Beach and Stuart. A main cause of erosion at this site has
been the Australian pines which are not a native specie. The
shade of these trees has killed the native beach grasses, and
since, the roots of the pines are not effective for soil reten-
tion, erosion has resulted.

Numerous vegetative plans will be tried at this site. In
some of these, the pines will be removed from the beach area and
other species will be planted. At one vegetation site, a float-
ing tire breakwater will be temporarily installed to determine if
it encourages the establishment of the new plantings.

Revetment construction will also be tried using Monoslab,
Turfstone and Lok-Gard blocks, all of which are patented. Con-
ventional concrete masonry units will also be used for a section
of revetment.

GULF COAST SITES

Basin Bayou, Florida

Basin Bayou, located on Choctawhatchee Bay in the Florida
panhandle is one of the Gulf Coast sites. The site is character-
ized by a bluff, fronted by a narrow sand beach. Among the
structures to be tested will be a Longard tube, installed as an
offshore breakwater. Another offshore breakwater will be con-
structed in three sections with different types of sand-filled
bags. A third offshore breakwater will be a "Surgebreaker,"
which is a patented device. It is constructed of precast, per-
forated, concrete modules which are usually placed by helicopter.

A "Sandgrabber" will also be constructed at the site. The
Sandgrabber is horseshoe-shaped in plan, and is constructed of
individual concrete blocks fastened together with steel tie rods.
Vegetation will also be tested and an attempt will be made to
stabilize the eroding bluff with a bulkhead. It will be con-
structed with sand-filled bags retained by hog-wire fence
stretched between timber piles.












The second Gulf Coast site was originally Sand Point, Texas.
It had to be dropped from the program however, because the local
sponsors could not meet the required 25 percent contribution of
the project costs.

Fontainebleau, Louisiana

The second Gulf Coast site is on Lake Ponchartrain at Fon-
tainebleau State Park, Louisiana. The relief is low with a nar-
row sand beach fronting extensive marsh lands. The plan of
demonstration includes concrete block revetments, a timber-tire
breakwater, filter-cloth revetments and extensive vegetative
measures. The concrete block revetments will utilize various
arrangements of Gobi blocks and Gobi mats. The breakwater will be
constructed offshore with timber piles upon which rubber tires
will be stacked. The tires will be held down with timbers strung
along the tops of the piles.

PACIFIC COAST SITES

Alameda, California

One Pacific Coast site is located on San Francisco Bay at
Alameda, California. This site is located in the most highly
developed area of any of the SEAP demonstrations and should
therefore be easily accessible to large numbers of people. The
site is characterized by a flat sandy beach fronting a bluff at
the top of which is a large road. Broken concrete pavement sec-
tions are strewn along this bluff in a half-hearted attempt at
shore protection. A large part of this demonstration will in-
volve the reuse of this rubble to construct more formal revet-
ments. In some cases, the concrete will be broken into more
blocky pieces before reconstruction to determine if that improves
performance. Other measures to be undertaken include an arti-
ficial tombolo which will be stabilized with vegetation and a
Longard tube offshore breakwater, a sand bag sill to protect
newly planted vegetation and a sand bag groin to retain a small
beach fill.

Oak Harbor, Washington

The other Pacific Coast site is at Oak Harbor, Washington.
The problem at the site is bluff recession which occurs during
high water levels. Demonstration devices include a gabion
revetment, a timber pile rubber tire bulkhead, a treated timber










bulkhead, an untreated timber bulkhead and a sand-cement bag
revetment. All of the devices utilize filter cloth for half of
their length and graded stone filter for the other half.

The timber pile-rubber tire bulkhead is similar in construc-
tion to the structure at Fontainebleau, Louisiana where it is used
as an offshore breakwater.

ALASKA SITES

Kotzebue, Alaska

The two Alaska sites will be at Kotzebue and Ninilchik.
Kotzebue is located north of the Arctic Circle at the tip of the
Baldwin Peninsula. The site is firmly ice bound most of the year
with open water occurring only during the summer months. The
shoreline is gravel and is heavily used by Eskimo fishermen who
beach their small craft there. The demonstration will utilize
steel fuel barrels which are found in abundance at the site.
These have been used as bulkheads in the past and the demonstra-
tion will involve their use as revetments and groins. Similar
structures will also be constructed of gabions containing gravel-
filled bags. The bags are necessary because there is no native
rock large enough to be retained by the gabion mesh. One groin
will be constructed of gravel-filled bags alone to study the
effects of ice on the structure.

Ninilchik, Alaska

These same materials will be used for groins at Ninilchik to
protect the toe of an existing log revetment. Ninilchik was
chosen as an alternate site after Seward had to be dropped from
the program due to lack of funds for the 25 percent local con-
tribution.

GREAT LAKES SITES

Port Wing, Wisconsin

One Great Lakes site will be located on Lake Superior at
Port Wing, Wisconsin and the other at Geneva State Park, Ohio.
The Port Wing site consists of a high eroding bluff with a high-
way near the top edge. The demonstration plan includes a bulk-
head constructed of railroad ties placed between vertical steel
H-piles, and revetments constructed with rubble tires, concrete
blocks and conventional riprap.












Geneva, Ohio

The Geneva site is situated on the south shore of Lake Erie.
The plan for this site includes three detached breakwaters and
vegetation. One of the breakwaters will be constructed of gabions,
one of Sta-Pods and the third will be a Z-Wall.

PROGRESS OF THE PROGRAM

The Corps' Divisions and Districts are now making final
plans for construction. The Oak Harbor site is already completed
and all but two of the sites should be constructed by the end of
1978. The Jensen-Stuart demonstration site will be completed
early in the spring of 1979. The Fort Raleigh site is still
being studied and has not yet been approved but if plans proceed
as expected, it too, could be completed early in 1979.

In addition to constructing demonstration projects, the pro-
gram will include monitoring of devices at other sites. In these
cases, the structures or vegetation have already been installed
by other interests. The panel has nominated 22 sites for moni-
toring, and they are:

Atlantic Coast

Charleston, SC
Buckroe Beach, VA
Pine Knolls Shores, NC
Hampton Nat'l. Wildlife Preserve, VA
Duck, NC
Uncle Henry's Fish Camp (Wilmington) NC

Gulf Coast

Key West, FL
Shoreacres, TX
Holly Beach, LA
Beach City, TX
San Leon, TX

Pacific Coast

Kualoa Regional Park (Oahu Island), HI
Siuslaw River, OR
Sunnyside Beach (Steilacoom), Puget Sd., WA












Great Lakes

Muskegon State Park, Tawas City, MI
Port Sanilac, MI
Sanilac Sec. 11 (Lake Huron), MI
Sanilac Sec. 26 (Lake Huron), MI
Tawas Point (Lake Huron), MI
Ashland, WI
Lincoln Twp. (Lake Michigan), MI
Little Girl's Point, MI

The exact number of monitoring sites will not be known until
it is determined how much money is left following construction of
the demonstration projects. The costs at many of the sites are
running higher than expected. The bids on the floating tire
breakwater at Pickering Beach, Delaware, for instance, had to be
rejected and the plans modified to reduce costs.

We are confident however, that the program will yield valu-
able information for the proper design of low-cost shore protec-
tion structures in sheltered waters.






























ENVIRONMENTAL MONITORING


OF THE

BEACH RESTORATION PROJECT

FOR THE

CITY OF DELRAY BEACH, FLORIDA








Mr. Richard H. Spadoni
Ocean Engineer and Biologist
Arthur V. Strock & Associates, Inc.
829 S. E. 9th Street
Deerfield Beach, Florida 33441










ABSTRACT


In 1978 a Maintenance Beach Restoration Project was completed in
Delray Beach, Florida. As part of the beach restoration project,
an environmental monitoring program was conducted which investi-
gated the effects of dredging on nearby coral reefs. Five reef
monitoring stations were established and monitored prior to, during,
and after the construction stage of the project. Water and sedi-
mentation samples were collected and evaluated throughout the moni-
toring period. Photography and photogrammetry were used to provide
visual records of the reef stations in determining if dredging was
affecting the reef. In addition to the monitoring stations, diver
surveys were conducted over the entire reef to investigate the pos-
sibility of reef damage due to contact with the dredge cutter head
or positioning anchor. Evaluation of the photographic and physical
evidence collected during the monitoring period suggested that tur-
bidity and sedimentation had no observable effect on the reef cor-
als. Diver surveys, however, revealed that reef damage had occurred.
The damage appeared to have been caused by a dredge anchor and anchor
cable.


INTRODUCTION

In recent years there has been increasing concern for the effects
of mankind's activities on the environment. Preservation of the
environment is now an important consideration in any of man's en-
deavors. Coral reefs living in the ocean waters of Florida may
be affected by attempts to preserve yet another natural resource;
the beaches.

Since the 1950's the State of Florida has experienced an astound-
ing growth rate, particularly in the coastal regions. Once barren
shorelines are now highly developed areas extensively used by resi-
dents and tourists alike.

Wide beaches provide recreational area and protect coastal develop-
ment from flood damage in the event of a major storm. Presently
many miles of Florida beaches are in a state of critical erosion
because they lack the dimensions to provide either ample recreation-
al area or storm protection.

A number of measures are available to control beach erosion and to
restore beaches. The dredge and fill operation is the most accep-
ted method of acccaplishing beach restoration in Florida. It is
common practice to obtain the sand needed for beach fill from off-
shore areas where large accumulations of sand occur in depressions
in the continental shelf. The fill is removed from these areas,
referred to as borrow areas, by dredging and placed on the eroded











beaches. The advantages are obvious in that the required recrea-
tional space and storm protection are provided with the construc-
tion. After the completion of construction an aesthetically pleas-
ing beach ,remains, similar in appearance to the beach prior to ero-
sion. However, turbidity and the subsequent sedimentation created
during dredging can have detrimental affects on nearby coral reefs.

Environmental monitoring of a reef system in close proximity to a
dredge-and-fill operation is an important addition to the engineer-
ing inspection and supervision. An environmental monitoring program
can provide for early warning of possible sedimentation damage to
nearby coral reefs. Inspecting and supervising engineers can then
institute directives to modify or cease potentially damaging dredg-
ing operations. During the 1978 beach restoration project of Del-
ray Beach, an environmental monitoring program was conducted on the
coral reef adjacent to the dredge borrow area.


DELRAY BEACH EROSION CONTROL PROJECTS

The City of Delray Beach has a recent history of severe beach ero-
sion. In the early 1970's major storms had reduced the beach width
over 100 feet and portions of Ocean Boulevard, the coastal state
roadway, were undercut and damaged. A concrete revetment was then
constructed but was not successful in stopping the advancing ocean;
Ocean Boulevard and the new revetment were damaged during a series
of Northeast storms in 1972.

A beach restoration project was undertaken in the summer of 1973.
Approximately 1.6 million cubic yards of beach fill were dredged
from an offshore borrow area onto the eroded beach. The initial
construction shifted the average Mean High Water Line 180 feet sea-
ward. The wide beach provided the recreational area and storm pro-
tection that Delray Beach had sought.

In 1978 a maintenance beach restoration project was completed;
570,000 cubic yards of beach fill placed over 1.7 miles of shore-
line. Beach fill was again obtained by utilizing an ocean borrow
area located approximately one-half mile offshore. The dredging
began in December of 1977 and continued through May of 1978.

The environmental monitoring program conducted during the 1978
beach restoration project began in October of 1977 and is still
underway as of this writing. It is the environmental monitoring
program, especially the investigations of the effects of the dredg-
ing on the coral reef, that is the subject of this paper.
























































































Dredging operations during the 1978 Beach Restoration Project in
Delray Beach, Florida


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Uil













THE CORAL REEF


Coral reefs are found primarily in warm, clear waters of tropical
seas. Tropical corals require water temperatures in excess of 160
centigrade and a relatively low rate of sedimentation to survive.
Coral reefs adjacent to southeast Florida are composed primarily
of soft corals, sponges and a minor proportion of hard, reef-build-
ing corals. These coral reefs are usually found offshore and in
deep water where sedimentation and temperature fluctuations are
minimal.

A coral reef lies to the east of the Delray Beach coastline. Many
of the tropical corals which presently grow on the reef are depen-
dent upon the Florida Current, a major warm-water current which
sweeps along the Florida coast from the Caribbean Sea. Delray Beach
is situated near the northern limit of the range of many tropical
corals; the influence of the Florida Current maintains warm-water
temperatures allowing for coral existence.

The western edge of the coral reef lies at a distance of approxi-
mately 4,000 feet offshore. In many locations steep, 15-foot ledges
rise up from approximately 60-foot depths of water to 45 feet on the
reef top, while in other locations the reef crest is only a few feet
above the ocean bottom. Live coral colonies grow on the surface of
an ancient coral reef, elevated above the sandy ocean floor. Ap-
proximately 10% of the reef surface is covered by live reef-building
(hard) corals. The most common species to be found include large
star coral, Monastrea cavernosa, brain coral, Meandrina meandrites,
star coral, Dichocoenia stokesii, large flower coral, Mussa angulosa
and same scattered patches of staghorn coral, Acropora cervicornis,
among others. The most abundant organisms growing on the reef are
the soft corals including gorgonians, sea whips and sea fans, and
numerous sponges.

The borrow area for the 1978 Delray Beach Erosion Control Project was
situated parallel to the coastline, extending from the northern City
limit to the southern City limit, a distance of 6,600 feet. The east-
ern edge of the borrow area, closest to the reef, was approximately
400 feet from the reef edge (see Plate No. 1). The primary threat to
the reef environment stemmed from the potentially damaging sedimenta-
tion which resulted directly from dredging. Those organisms which
were most susceptible to this type of damage were the benthic marine
invertebrates, especially the hard corals, which could not move out
of the area as could fish or other motile creatures. Also, the mor-
phology of many species of hard coral is such that sediment can ac-
cumulate in depressions on the coral colony. Since hard corals are
inflexible, the possibility of currents or other water movements re-
moving sediment from the organism was less than with soft corals


























































Brain Coral found on the reef oif of Lhe Delray Beach coastline.











42












which could sway and shed the sediment which had settled on them.
Sediment can smother the coral polyps, interrupting respiration
and feeding resulting in the death of the organism. A second po-
tential threat to the reef during the project was the possibility
of physical damage due to accidental collision of the dredge cut-
ter head or dredge positioning anchors with the reef.


THE ENVIRONMENTAL MONITORING PROGRAM

Reef Monitoring Procedures. Initially, diver surveys utilizing un-
derwater photography were conducted along the natural reef and with-
in proximity of the borrow site to determine the general overall
make-up of the reef community. Sediment thickness and water depth
charts were used in the location of the natural reef with reference
to the borrow site. Five monitoring stations were chosen on the
basis of two criteria: first, the general location of the stations
were selected to situate three stations adjacent to the borrow area,
with two more stations, one north and one south of the borrow area.
The stations were spaced at approximately equal distances along the
project area (Plate No. 1). The second criterion was to select the
station locations to include a variety of hard coral species.

The stations were staked out on the reef as a 10 foot by 10 foot
square, providing 100 square feet of reef surface to monitor. A
comprehensive program of photography and photogrammetry was conduc-
ted at each monitoring station. Each station was photographed pri-
or to, during, and after completion of the dredging project. These
photographs provided visual records of the monitoring stations from
the pre- to post-construction period. Individual coral colonies
were also photographed and rephotographed with a macro-closeup cam-
era which allowed both identification and detailed information as to
the relative well-being of the organism.

Sediment jars were placed at each reef station and periodically col-
lected and analyzed as to content. Background information was col-
lected beginning ten weeks prior to dredging and continues to be col-
lected after the completion of dredging operations to establish the
natural rates of sedimentation. In conjunction with gathering in-
formation on sedimentation rates, turbidity data was obtained from
water samples taken at each monitoring station. Background turbidi-
ty samples were collected prior to, during, and after dredging to
determine the levels of turbidity normally occurring in the vicini-
ty of the coral reef.

A Littoral Environmental Observation Program was conducted concurrent-
ly with the monitoring study throughout the life of the project. The
ocean variables observed and recorded included data on wave action,










currents, water clarity and weather conditions. This information
was gathered twice daily, seven days a week and recorded on stand-
ardized littoral environmental observation forms, and was used to
correlate ocean conditions and sedimentation rates found on the
reefs.


ANALYSIS

Water Turbidity Evaluation. Water samples were collected at every
station during each visit to monitor the reef. Additionally, wa-
ter sampling and turbidity analysis were conducted by the dredge
contractor in the vicinity of the beach and the dredge cutter head.
All water samples were analyzed with a Hach 2100A turbidimeter.
The results were recorded in Nephelometric Turbidity Units (N.T.U.'s),
a measurement of light reflected by sediment suspended in the wa-
ter sample.

Turbidity measurements taken from water collected on the reef sta-
tions demonstrated no discernible increase in turbidity during
dredging operations when compared to samples taken prior to or af-
ter completion of the project. In only one instance did any of the
water samples register a reading of over 1.0 N.T.U., and it occurred
prior to the commencement of dredging and followed five days of
rough seas. Quite often water samples taken on the reef were found
to be of greater clarity than tap-water samples taken in our of-
fice.

Monitoring station no. 2 had the highest readings in 60% of the oc-
casions when samples were taken. This can be attributed to the
fact that station no. 2 was located on a section of reef which was
low in topography ccpared to the other stations.

Samples taken by the dredging contractor in the vicinity of the
beach were occasionally found to exceed the state water quality
standards for Class III waters of 50 J.T.U.'s (Jackson Turbidity
Units). Samples taken at a distance of 200 feet from the cutter
head conformed to Class III water standards.

Sedimentation Rate Evaluations. Sediment samples were collected
at each monitoring station in conjunction with water sampling for
turbidity measurements. A sediment jar was placed adjacent to
each monitoring station on the reef. As with turbidity, sedimen-
tation samples were collected before, during, and after the con-
struction period.


























































Environmental Monitoring Station prepared for photography








45










Except in one instance, the sedimentation rates during the construc-
tion reflected little change from the natural rates. Sediment sam-
ples collected on February 19, 1978 indicated a higher than normal
sedimentation rate. The greatest increase occurred at monitoring
station no. 2 which was located nearest the dredge. The sedimen-
tation rate prior to the increase was 0.00494 grams/cm2/day but
for the time interval from February 4 to February 19, the rate in-
creased to 0.16395 grams/an2/day. Quality control reports from
the dredging contractor revealed that the pipeline which transpor-
ted dredged materials from the dredge to shore had ruptured on two
separate occasions. The incidents occurred on February 8th and
again on February 16th during rough seas. The combination of the
broken pipeline during a period of active pumping and rough seas
spread sediment on the reef, especially in and around monitoring
station no. 2. Aside from the exceptions of the ruptured pipeline',
sedimentation rates were fairly consistent throughout the monitor-
ing period.

Photographic Evaluations. A program of photography was conducted
throughout the monitoring period. Prior to dredging, the photo-
graphic technique of photogrammetry was employed to visually re-
cord each station. A series of 32 photographs were taken of each
10 foot square station and overlayed to form a visual representa-
tion of the entire station. By utilization of this technique be-
fore and after the construction period, comparisons were possible
to determine if any environmental changes occurred. In addition,
individual benthic organisms were photographed and rephotographed
utilizing close-up techniques. Close-up photography yielded the
detail required for identification of the organism eliminating the
need of relying solely on diver identification or the removal of
the organism for identification purposes.

Great care was taken to leave each station undisturbed. Trisponder
electronic positioning equipment was used to obtain precise loca-
tion of each station. Thus, it was possible to return to each sta-
tion after an extended period of time and determine if any long-
term changes had occurred.

Close inspection of the photographic evidence revealed no observ-
able damage to the reef stations to date. This information sub-
stantiated the results of turbidity and sedimentation measurement
which revealed little change from natural conditions on the reef.

Diver Observation. In addition to the comprehensive investigations
of the monitoring stations, divers periodically swam along the reef
adjacent to the 6,600 foot long borrow area. Diver surveys were
performed to observe the reef lying between the environmental sta-
tions. Of primary concern was the possibility of physical damage
to the reef caused by contact with the dredge cutter head or posi-
tioning anchors.



























































Biologist and Ocean Engineer Richard Spadoni recording the loca-
tion of photographed corals








47












On May 31, 1978, while engaged in a diver survey of the reef, an
area of damaged reef was discovered. The damage consisted of up-
rooted soft corals, fragmented sponges and domed coral heads which
were overturned or scarred by the dredge anchor and anchor cable.
The area damaged was triangular shaped and extended from the west-
ern edge of the reef to a point approximately 350 feet to the east.
The top of the reef appeared to have been scraped and many of the
sessile invertebrates damaged. The most severe damage occurred in
the areas of highest topography while low profile organisms grow-
ing in depressed areas of the reef were undamaged. Also observed
were trenches approximately 6 feet in width and oriented in the
east-west direction near the eastern edge of the damaged area. The
trenches appeared to have been made by the dragging of an extreme-
ly heavy object across the reef.

Further diver surveys found no other areas of the reef damaged.


CONCLUSIONS

There has been no detectable reef damage due to sedimentation or
turbidity during the construction period. Several factors contri-
buted to the lack of turbidity or sedimentation damage to the en-
tire reef system:

1) The location of the limits of the borrow area was no clo-
ser than 400 feet to the nearest reef and typically found 700 feet
from the reef.

2) Currents oriented predominantly in the north-south direc-
tion carried sediment west of, not over, the reef.

3) Water depths in the borrow area and over the reef ranged
from 40 to 65 feet, somewhat deeper than in other beach restora-
tion projects in southeast Florida. Deeper water minimized bottom
turbulence due to wave action which allowed suspended sediment to
settle out in a relatively short period of time. Also, quiescent
weather during the construction period contributed to a fairly
calm wave climate, further reducing bottom turbulence.

Although there was additional sedimentation attributable to the
ruptured underwater pipeline, the area of the reef which received
the majority of the sedimentation, monitoring station no. 2, was
not observably damaged. One reason for this was the low topography
of the reef which was only several feet above the sandy borrow area.
Also, numerous large pockets of sediment existed within the reef
in this area. Under natural conditions the sedimentation rate of
monitoring station no. 2 was approximately 2.5 times greater than





































































Appearance of the.coral reef adjacent to the damaged reef










LQ
























































Port ion of the damaged reef


P
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~~J 'd:












the rates measured on the remaining monitoring stations. The cor-
als living in this area were species which were apparently more
tolerant of sedimentation and were able to survive the increased
sedimentation rates due to the ruptured pipeline.

The reef damage which was discovered by diver survey appeared to
have been caused by an anchor and anchor cable from the dredge.
The reef damaged area occurred directly seaward of the last working
position of the dredge and was discovered within a few days of its
occurrence.

In subsequent observations of the damaged reef it was noted that
algae was beginning to grow in areas which were scraped. Sections
of broken sponge which had littered the area were less evident,
but the absence of large sponges in the damaged area was obvious
in comparison to the adjacent undamaged reef. Numerous gorgoni-
ans were pushed over and lying on the reef but continued to sur-
vive, in most cases retaining some attachment to the reef.

As of this writing, investigations of the damaged reef still con-
tinue. Answers will be sought as to the degree of sessile inver-
tebrate repopulation which can be expected and as to whether the
partially damaged coral heads will survive.

The daily reporting system utilized by the dredge contractor to
provide dredge locations and turbidity measurements proved inade-
quate. Lag times between receptions of reports by the engineers
and questionable dredge positioning accuracy made effective use
of report results difficult. Quality control reports were typi-
cally submitted to the engineers prior to partial payment requests
from the dredge contractor. Daily reports were received as much
as one month after they had been completed. In the case of the
reef damage, quality control reports made no note of anchors hav-
ing been placed in the vicinity of the reef damage.


RECaMMENDATIONS
The following are recommendations which would provide additional
safeguards against the possibility of reef damage occurring dur-
ing beach restoration projects:

1) The monitoring of water quality by turbidity measurements
should be incorporated into a total program to be the responsibili-
ty of the engineers overseeing the restoration project. There is
a certain amount of lag-time between the sampling and measurement
of water quality and reports to the engineer. If turbidity is
high, sedimentation rates on the reef may be unacceptably high dur-











ing this time-lag resulting in reef damage. If turbidity rates are
found unacceptable for State of Florida Class III water quality
standards in the proximity of live reef, the engineer should halt
dredging operations until the situation is corrected.

2) Relocation of the dredge in the borrow area or the move-
ment of anchors should be monitored by the engineers. This will
insure that the dredge remains within the limits of the borrow area
and that anchors are not dropped on coral reefs.

3) A general reef survey should be a requirement of the State
of Florida prior to issuance of construction permits for beach res-
toration. Potential problem areas could be identified in the plan-
ning phase of the beach restoration project and adjustments made
in the borrow area. In this manner, project delays during construc-
tion due to concern over sedimentation damage to nearby reef would
be avoided.

4) Every effort should be made to insure that the construc-
tion period occurs in the sumner months. The ocean is normally
much calmer in the summer months allowing for rapid settlement of
suspended sediment.

























Cn


DRAWING NUMBER:
I48/8.07-10-0O/A
m ARTHUR V. STROCK 8 ASSOCIATES, INC. DA8TE: 10 Y:
DE LRAY BEACH ,UvfE 78 C./s
COMM.N2 40/8d07
PLATE NO.1
53












REFERENCES


1. Smith, F. G. Walton, Atlantic Reef Corals, University of Miami
Press, Coral Gables, Florida, 1948.




























SHORELINE STABILIZATION


AND ITS

IMPACT ON THE RECEIVING WATERS











Cherie Down
County Biologist
Brevard County Health Department
Engineering & Pollution Control
2575 N. Courtenay Parkway
Merritt Island, Florida 32952












ABSTRACT


The United States of America has 58,000 miles of shorelines, in-
cluding seashores, estuaries, rivers, lakes and springs.

Oceanshores, the transitional zone between dunes and the submerged
photic zone, play an important biologic role both to the submerged
and the dune areas.

Estuarine marshes and other intermittent land-water interfaces act
as an exchange medium between the uplands:and the submerged sea-
grass beds.

Since the transitional zone and estuarine shores have a substantial
impact on the receiving waters, stabilization methods play a great
role in their well-being.

Waterfront stabilization using natural vegetation is an effective
and economical way to combat erosion and at the same time, im-
pose the least amount of detrimental effect on the receiving waters.











SHORELINE STABILIZATION


AND ITS

IMPACT ON THE RECEIVING WATERS


The United States of America has 58,000 miles of coastlines, 15,000
of which are erosion-prone and troubled, with 2,700 in critical con-
dition.' These shorelines include miles of rivers, waterways and
other shorefront areas, and the target of 53 per cent of the total
population density of this country.Z

The State of Florida has an approximate 1,300 miles of oceanfront.
Here, we have 30,000 freshwater lakes, approximately 1,700 streams,
and 20 major freshwater springs.2

There are no estimates of the miles of artificially created water-
front canals, but with 34 coastal counties, one might guess at the
numbers.

Today, I would like to focus on the subject of waterfront areas,
what they are, how important they are, and, possibly, how to go
about stabilizing them with using natural methods.

I would like to discuss, in general, two types of shorelines with
erosion problems. First, the ocean shores, with the rise and fall
of tides, storm tides, and hurricanes; and, next, the estuarine
shores with wind-driven tides and subject to seasonal inundation
with periodic effects of lunar tides.

The Atlantic Ocean shores have a series of dunes to serve as their
natural defense system. Depending on the degree and the intensity
of a storm, the destruction or breaching of this system leads to
various degrees of storm damage and erosion.

The erosion barrier function of the dune system, however, is only
one of many functions of the dune line. This area, an immediate
neighbor of the intertidal zone, has a close relationship with
the land-water interface, which is a complex of habitats forming
a productive and fascinating area.

I would like to, briefly, discuss the general components of the
beachfront, forming this system.

The ocean nearshore areas within the photic zone have a complex of
communities which relate to the deeper areas of the sea floor on









one side, and the upland shores on the other. The Atlantic Ocean
nearshore areas, with the influences of the Gulf Stream, have a
complex of sloughs and ridges, reefs, serpulid worm formed rocks,
and bottom vegetation, supporting a complex habitat of marine life.

Utilization, regeneration, and recycling of nutrients are among the
most important functions of this zone of dynamic reefs and nearshore
life cycles.

The continual cycle of binding and releasing of minerals and nutri-
ents and the exchange of the byproducts with the "next,door neigh-
bor" zone organisms, continues in the nearshore areas. This process
takes place in the seaweed and seagrass beds on the reefs, and
eventually within the turbulent wave action areas where waves break
on the shoreline and link this nutrient regime to the intertidal
zone.

Each of these zones helps harbor and feed different life stages of
many species of fish, shrimp and other sea life, all of biological
and eventually economic importance.

Nearshore non-vegetated sloughs, where shrimp are caught, have re-
cently been found to be used by sea turtles for hibernation. With
temperatures at a constant several degrees above seawater, these
sloughs apparently provide a stable area for the wintering sea
turtles.

The intertidal zone supports a different kind of community whose
existence hinges on the periodic inundation by the rise and fall
of tides. This area, with the community complex of little crabs,
coquina clams, washed ashore small fish, and many more organisms,
in turn feed, and are food for shorebirds, and small shoreline
mammals of the shoreline area. These intertidal zone inhabitants
also have a unique relationship with the upland dunes and its animal-
vegetation communities.

The submerged seaweeds through the passage of seasons, have their
turnover and wash ashore. If one would take time to examine a long,
intermittent ribbon of seaweed, one would find on the Atlantic
coast, predominantly seaweeds Sargassum, Gracilaria, hyperea, fresh
or decaying, all rolled together, covered with bryozoans, weighed
down with minute molluscs and crustaceans, mixed with sand and
often covering the length of the shoreline. Each succeeding tide
forms another line of this vegetation and associated organisms.
The highest tide lines drive the vegetation up into the sea oats
and panicum grass complex beginning at the base of the dunes.
This natural action provides organic nutrients to the dune habitat.









Many people mistakenly believe the decaying seaweeds to be offensive,
dirty and not befitting a "clean" beach. In some areas, at much
expense, these weeds have been removed and carried to the city dump.
Such a practice seems to be a waste of public works money. This re-
moval of vegetation further deprives the dunes of naturally avail-
able free nutrients.

Natural systems endure and have evolved through coexistance to the
present time. Just as we take clean air and clean water for granted,
we manage not to notice a stable, intact dune system as nature's
defense mechanism. What goes unnoticed by man is in reality, a very
efficient, complex, and conservative method to allow life on all
possible levels to continue and promote itself.

Man, the newcomer, is an invading species and more often than not,
works to promote man, mostly in ignorance of the natural system
within which he lives. We are fortunate creatures to have the brain
and the technology, and need to develop an awareness of other tech-
nologically sound systems in nature within which, in order to survive,
we must operate.

I would like to return my discussion to the dunes and focus on their
plant life.

Dune plants may appear, conspicuous and green, or may be scattered
and not seem evident.3 In either case, they have a root system under
the top sand layer which holds dirt and sand, traps moisture, and
can fix nutrients, enabling it to support a variety of shoreline
organisms.

Where growth is green and evident, dune line vegetation offers habi-
tat and produces seed food and fruit for birds, small reptiles, crabs,
and a variety of other organisms. In turn, the birds and crabs,
through their living and nesting provide nutrients to the dune ve-
getation.

All natural dune vegetation is salt tolerant, and through the trial
and error method of time is most resistant to the destructive forces
of salt, wind, dessication and invading organisms coexisting with it.
In short, a natural plant system on the dunes is a winning system.
Through the passage of time, the fittest of these plants have sur-
vived. We would learn an important lesson if we mimic nature's
system in dealing with natural problems. There is a reason for sea
oats, panicum grass and railroad vines to grow in the foredunes.
This area is most apt to have salt spray, tidal influence and be
sand blasted. The above vegetation types, with firm roots, can
withstand high winds and not break. In this way they can provide
stability in the interim zone between high tide and the next com-









munity of vegetation of the seagrapes, palmetto complex with taller
and firmer but nore brittle trunks.

Thus, the shoreline, with the submerged and emergent zone form a
stable biological habitat. The degree of stability of this habitat
and its ability to handle storms, determines the amount of natural
protection man may expect, if man plans to live close to the ocean.
Although no biologist claims to ward off hurricane effects with the
growth of vegetation on the dune systems, it has been demonstrated
over and over again that storm effects can be minimized if healthy
dunes and natural dune weeds exist to protect the uplands.

The Brevard County Dune Revegetation program was created on the
basis of the above assumption. In Brevard, a group of biologists
set out and vegetated a manmade dune. Several months after the ve-
getation, a storm came along and washed out much of the beach and
was at the front steps of several nearby homes and condominiums.
The new dune line and vegetation, however, held fast.4 This
finding enabled the County to create a program to eventually re-
build the dunes, close all the dune gaps, and vegetate wherever
vegetation was needed. It also brought us head on with the pro-
blem of ocean access, where we had to create crossovers for pe-
destrians. With substantial State aid, we are now in the process
of creating a crossover at every county-owned footpath, right-of-
way, and street end. These access areas range in width from 6 feet
to 200 feet. In some areas, a ramp and a set of stairs were all
that was necessary. In other areas, small boardwalks with hand-
rails were constructed. Not all of these crossovers have parking
provisions and none have restrooms or other park-type comforts.
These walkways are just what they were supposed to be, an access
to the ocean anJ are used heavily by the neighboring residents
and visitors.
Lately, we have noticed that the walkways also serve as places for
teenage social gatherings. They also serve as the gathering place
for fishermen and families who can be seen sitting on folding chairs
in the evenings, enjoying the sunset. Most of all, however, the
raised wooden access areas protect and promote healthy dunes, with-
out cuts or gaps.

The Dune Revegetation program has received much publicity. The most
important consequence of this publicity has been the awareness created
in the minds of the county residents living on the ocean. We have
groups of condominium residents who have built up their own dunes,
harvested and planted their own sea oats, creating green areas where
there had been none before. We also have oceanfront homeowners who
have considered the duneline as part of their own yard, and have
planted, fertilized and watered the dune vegetation.









In order to maintain and meet the county needs, Brevard County began
a Dune Vegetation Nursery where the staff experimented with different
methods of growing dune vegetation. Some fascinating and very ex-
plicit methods have been developed by the county staff and the re-
vegetation crew including facts such as when to harvest, how many to
put in each pot, how long to grow, and how deep to plant plants for
best results on the beach and under natural conditions. There is
so much progress in this program that an update of our 1976 Dune
Revegetation Report is now in process.

I would like to change the focus of this talk and address a different
type of waterfront: the inland waters.

The State of Florida has 4,308 square miles of inland waters. These
waters include estuarine areas, lagoons, aquatic preserves and shell-
fish harvesting areas. They also include lakes, streams and springs.5

As in oceanfront areas, inland waterfront is a most desirable location
for development. I would like to discuss the inland waters, especi-
ally estuarine areas, including the inshore salt water systems.

The State of Florida enjoys a very extensive tourist industry, much
of which is based on the water resources of the State.

Another important industry of the State of Florida is its commercial
fishing products. In 1975, the approximate dockside value of the
State of Florida's fishing industry, including shellfish, shrimp,
crab, and fish catches, was 73.7 million dollars.0

For their survival, shellfish, shrimp, crabs, and around 80 per cent
of the fish caught in Florida waters depend on the brackish to fresh
water areas, constituting inland waters. The upland, consequently,
bordering on these waters, have a life or death-type effect upon them
and their resources. What we build, how we build, and where we build
can influence and dictate the survival of the very resources that
drew us here in the beginning.

There has been extensive research performed to measure and assess the
value of marshes and wetlands. Fresh or salt, these important bio-
logical "food factories" have been studied for their value as nursery
grounds, their capabilities in water purification, their capacity
as water reservoirs, and many other functions beneficial both to
their neighboring upland, and their neighboring lakes, rivers or
estuaries.

When one thinks of marshes, vast areas of green come to mind, with
birds feeding and tide pools reflecting the sky. Over the years
and with increased growth, much of this picture has changed. Through
dredging and filling, the size of much of our natural marshes has









been reduced. Waterfront development has brought many back yards
to the edge of the river or estuary. By dredging part of the former
marsh, enough fill material is generated to cover and raise the rest
of the marsh for development. The deeper dredged areas are thus
turned into navigable canals, creating fingers of water reaching in-
land. In many parts of Florida, the house foundations meet the mini-
mal flood insurance requirements by a few inches.

I would not care to go into the politics or economics of this type
of waterfront housing, but I would like to focus on the newly created
problems of this type of waterfront development and some possible
solutions to their erosion problems, with minimal detrimental impact
on the receiving waters.

As in the oceanfront, and as in a natural marsh and river system, one
could visualize a mini zone of upland intermittent aid submerged
areas adjacent to waterfront development.

Just as in the oceanfront, nature has a strict and conservative budget
of nutrient uptake and release which ties in the upland, the marsh
system and the submerged areas. Briefly, upland rains bring in moisture,
topsoil nutrients, and minerals to the marshes, where the marsh ve-
getation would take up and store these components in its living tissue.
Vegetation and their root system here helps form a spongy, muddy soup,
serving as a nursery ground for much of the eventual seafood we con-
sume. The seasonal and slow release of the components from the marsh
to the submerged areas in turn promotes underwater meadows, very rich
in seaweeds and seagrasses. These primary producers, in turn, pro-
cess the upland handouts and generate their own food and release
system.

An estuarine area, harboring this submerged vegetation also supports
secondary producers such as amphipods and isopods, and eventually
tertiary life: fish. An eatuary, reaching from the 36+ parts per
thousand salinities of the ocean to the fresh waters oT the upland
river, is responsible for the eventual production of some 80 per
cent of all of our offshore fish, and 100 per cent of the shell-
fish, crabs and shrimp.
Recently, in a joint venture with NASA, Brevard County completed
mapping the submerged grassbeds of the county. Findings indicate
that Brevard County has approximately 78,600 acres of seagrass beds.
These grassbeds are of vast importance to the economy of the county
since, directly or indirectly, they are responsible for the basis
of a substantial commercial fishing industry. In 1975, the whole-
sale income of the Brevard County fishing products was approximately
3.4 million dollars. Add to this figure the sports fishing benefits,
the sale of gas, boats and other water-oriented equipment, and one
would realize the importance of maintaining the integrity of these









inside waters.


An economic analysis of the cost of seagrass restoration conducted
at the University of Miami estimates an approximate price of $8,000
to seed one acre of submerged land.8

How we handle the waterfront has a direct impact on the above re-
sources. Every waterfront industry, every drainage ditch, every
waterfront homeowner exerts an impact on the receiving waters. The
methods used to stabilize waterfront areas can play an impressive
role in the type of impact affecting the water system. A choice
exists in the manner of stabilizing waterfront, a choice not always
evident to many people. Waterfront inhabitants need to be educated
just as the oceanfront residents in Brevard County were educated
in the course of the revegetation program.

A healthy stand of spartina, followed by mangroves and followed by
a narrow zone of natural upland vegetation, if given a chance will
combat erosion in a much more effective way. In erosion-prone areas,
coquina rocks or similar material, and spartina, function more ef-
fectively than vertical seawalls. Seawalls are a case of overkill
in many waterfront areas of the State of Florida. Sometimes sea-
walls, when not needed, seem to resemble a viral infection. When
one is built on a natural shoreline, others follow, at times,
through necessity, more than through choice. Seawalls create
corners which cause erosion on the neighboring properties. If one
could discourage the first seawall from being built, there may well
be no need for any at all.

Any natural method to slow down or trap the upland exotic chemicals
and nutrients will aid the receiving waters by eliminating assimi-
lation workloads. A Central and Southern Flood Control District
study indicated substantial phosphorus and nitrogen removal from
upland runoff when this runoff was allowed to pass and filter
through a vegetation zone. Of course, the slope, intensity and
types of vegetation play a role in the above results.

Many plants, such as mangroves, have a three-fold function for the
zone at the edge of water. Mangroves can combat erosion, uptake
and release nutrients, and provide an important habitat for sub-
merged organisms.

Department of Natural Resources and the Sea Grant program have numer-
ous publications dealing with the planting of mangroves.8

I see a real need for first, defining areas where erosion problems
could be solved by planting of natural vegetation, and, next, a
program to educate the engineer, architect, builder and finally,
the homeowner in his responsibility to his land and his water.









Brevard County has started to grow red and black mangroves in the
nursery for transplant purposes. The causeway waterfront area
bordering our rivers pose as a good candidate for such a transplant
effort.

Another advantage of a natural shoreline is the gradual slope of
the land leading into the water. Homeowners with small children
should find an advantage in the sloping shoreline, versus a drop-
off shoreline created by seawalls.

I would, personally, rather see the accomplishment of better water-
front stabilization methods handled through:public education and
awareness than through regulatory agencies. Given a choice, and
an assurance of the same degree of protection, I believe people
would tend to landscape with natural methods in mind. I believe
it is the job of a regulatory body to make information available
to whoever needs it, publicize that information, and thus provide
the waterfront landowner with a choice.

Many natural systems have existed long before we arrived. Our aware-
ness of these systems may play a major role in our survival on this
planet.













REFERENCES



1. MacNeil Lehrer Report. 1978. Building on the beach.
Educational Broadcasting Corporation.

2. Simon, A. W. 1978. The thin edge. p. 5. In A. W. Simon,
The thin edge. Harper and Row., New York.

3. Clark, J. 1976. The sanibel report. Conservation Founda-
tion, Washington, D. C. 305 pp.

4. Brevard County Dune Revegetation Committee. 1976. Brevard
County dune revegetation report. Brevard County, Florida.


5. Erhart, H., and A. Burt. 1974. A
Erhart, H., and A. Burt, Florida
Burda GmbH., West Germany.


unique place. p 8, In
a place in the sun.


6. National Oceanic and Atmospheric Administration. 1977.
Florida landings, annual summary. 1975. Washington, D.C.
17 pp.


7. Down, C., 1978. Vegetation and other
County bar-built estuaries. NASA.
Dept., Rockledge, Florida 92 pp.


parameters in Brevard
Brevard County Health


Shorhaug, A. and Austin, B. C. 1976. Restoration of seagrasses
with economic analysis. Environmental Conservation
3:(4). 259-262.





























POLITICAL PROBLEMS OF


EROSION CONTROL













Lee E. Koppelman
Executive Director
Long Island Regional Planning Board
Veterans Memorial Highway
Hauppauge, New York 11787

and

DeWitt S. Davies
Principal Planner
Long Island Regional Planning Board












POLITICAL PROBLEMS OF EROSION CONTROL


Lee E. Koppelman
Executive Director
Long Island Regional Planning Board
Veterans Memorial Highway
Hauppauge, New York 11787

DeWitt S. Davies
Principal Planner
Long Island Regional Planning Board



ABSTRACT

The science and technology of shoreline erosion control is fairly
well established. Engineering solutions are available for the
majority of situations. Financing, even when costly, is often
manageable. Implementation of planned projects, however, often
falters due to public opposition that counterposes environmental-
ists vs. engineers; public agencies vs. private interests, and
shoreline property owners against one another. In short, it is
the political aspect of erosion control that is the deciding
factor even in cases that directly affect property and human
safety. This paper examines two examples of current controversy
on Long Island. The first is of long-standing debate involving
the partially completed groin field at Westhampton Beach a pro-
ject that had its genesis in the 1938 hurricane that devastated
the south shore of the Island. The second is a new twist to an
old theme. It deals with an attempt by the National Park Service
to secure Congressional amendments affecting the Fire Island
National Seashore to allow for the establishment of a dune dis-
trict and enable the Service to acquire storm damaged properties
within exempted communities. Examinations of the issues and
tactics in such disputes may offer useful insight for erosion
control professionals.












Introduction

Various shoreline management problems have resulted from
man's use of the shoreline and adjacent land. The natural erosion
of the shore has become a problem where permanent structures,
buildings or roads are threatened with destruction, either because
of long-term shoreline changes, or the short-term effects of hur-
ricanes and northeasterss". Sandmining, channel dredging, stabi-
lized inlets, and shore protection structures have created situa-
tions where the natural rate of erosion affecting both beaches and
marshes has been increased.
People's memories are also short. They fail to remember,
take into consideration, or perhaps are not informed of the devas-
tating shoreline destruction beaches were literally swept clean
of all human development caused by the September 21, 1938 and
August 31, 1954 hurricanes.(1) Loss of life is also a potential
hazard; 45 people were killed or listed as missing on the south
shore of Long Island as a result of the 1938 hurricane. Extensive
development of Long Island's shorelines has occurred without due
consideration for the dynamics of shoreline topography. The re-
sult of this disregard has been increased shoreline damage on an
annual basis.
Shoreline damage caused by wave and tidal action has resulted
in the construction of shore protection devices and the placement
of beach fill. Such projects have been financed by private indi-
viduals, beach associations, local municipalities, the State of
New York and the Federal government, and have often been con-
structed on a piecemeal basis without a comprehensive evaluation
of their potential effects on large segments of the shore.(2) The
practice of constructing groins, seawalls, and bulkheads, as well
as the re-building of beaches by filling with dredged materials is
extremely expensive. The U.S. Army Corps of Engineers estimates
that the initial cost for beach restoration by sandfill is roughly
157 million dollars for the south shore of Nassau and Suffolk
Counties, and 59 million dollars for the shore between Orient and
Montauk Points, and about 103 million dollars along Long Island's
north shore.(3) Unless care is taken during the design of shore
protection devices, they could interfere with the natural equili-
brium of coastal processes, and hence may adversely affect nearby
shore areas by diminishing their supply of sands; they are also
inherently dependent on the dynamics of the littoral zone, and may
not perform their intended function. Ideally, future development
of Long Island's shorelands should be controlled to lessen the
need for coast stabilization measures. Land use planning should
be based on an understanding of the processes affecting the con-
figuration of the shoreline, as well as the factors which cause
the need for shore protection.











Nevertheless, developments are extant and measures to protect
life and property are necessary. Management options can generally
be polarized as to structural versus non-structural solutions.
Land use controls and deliberate deterioration policies (let nature
handle the problem) are obviously more feasible where development
has not occurred. Such benign approaches applied to existing
communities signal an acceptance for the eventual elimination of
buildings by grace of storm or condemnation. The political and
policy issues raised by these choices often overshadow the basic
concern for shoreline protection.
Conversely, structural solutions are not without controversy.
Questions of durability, cost and potential negative impact on
downdrift properties must be successfully addressed.
In general, the science and technology of shoreline erosion
control is fairly well established. Engineering solutions are
available for the majority of situations. Implementation of
planned projects, however, often falters due to public opposition.
In short, it is the political aspect of erosion control that is the
deciding factor.
This paper examines two examples of current controversy on
Long Island. The first involves the partially completed groin field
at Westhampton Beach. The second deals with proposed Congressional
amendments to the Fire Island Seashore Law to create a dune dis-
trict and provide for the condemnation of storm damaged structures
in exempted communities.
The case studies are preceded by a brief discussion of the
erosion problems of the south shore, and a description of the
myriad array of plans, programs, policies, and regulations per-
taining to erosion control for this area.

The Erosion Pattern

The south shore of Nassau and Suffolk Counties can be divided
into two physiographic sections: an eastern headlands section
characterized by a narrow beach at the base of a bluff or cliff,
and a western barrier complex formed by a series of barrier islands
and a barrier beach separated from the mainland coast by lagoons
and salt marshes.(4)
The headlands section, which extends 33 miles from Montauk
Point westward to Southampton, has suffered severe erosion. It is
classified as a glacial deposition coast. The headlands are char-
acterized by truncated hills of varying height and steepness
fronted by a narrow beach of gravels and coarse sand.
The barrier complex section stretches approximately 73 miles
from Southampton to the Nassau County/Queens boundary. This
section of the Nassau-Suffolk coast has been shaped primarily by
marine deposition; it is classified as a barrier coast by
Shepard.(5) At the present time, five artificially maintained












tidal inlets -- Shinnecock, Moriches, Fire Island, Jones and East
Rockaway -- break the continuity of this reach. The four barrier
islands separated by the inlets Long Beach, Jones Beach, Fire
Island, Westhampton Beach -- and the barrier beach at Southampton
are near the northern end of the nearly continuous chain of 281
barrier islands and beaches of 100 or more acres each along the
Atlantic and Gulf coasts.(6) These long, narrow strips of sand
vary in width from less than 0.1 mile to over 1 mile in localized
areas and are continually being remolded by waves, wind and cur-
rents. The ocean beach in this section varies in width from a few
feet in the eastern portion to over 500 ft. in localized areas;
the average width is between 100 and 200 ft. Behind the shores
of these barriers, a series of irregular sand dunes rises to 30 ft.
in height. They display steep wind-and wave-eroded slopes on the
seaward side and gentle slopes often stabilized by beach grass on
the landward side. The barriers are separated from the mainland
by interconnected tidal lagoons: Shinnecock Bay, Moriches Bay,
and Great South Bay. West of Fire Island Inlet, the tidal la-
goons are nearly filled with marshy islands and tidal deltas. The
barriers, subject to drastic alteration as a result of storm
events and net westward movement as a result of longshore trans-
port, are extremely unstable. The position and number of south
shore tidal inlets have changed frequently within the historic
past. Catastrophic storms have cut new inlets through the barrier
islands. Some of these inlets have filled naturally due to the
rapid movement of large volumes of littoral sediments from the
east to west along the shore; others have been maintained through
channel dredging and jetty construction. The westward elongation
of Democrat Point at Fire Island Inlet provides a striking mani-
festation of the dynamic character of the barrier.
The longshore transport pattern along the south shore is
strongly unidirectional from east to west. This is due to the
exposure of the south shore to waves generated by winds from the
south and east. Net transport direction to the east occurs only
in the area immediately to the west of Fire Island Inlet where it
appears to be a result of tidal currents and wave refraction.(4)
The rates of longshore transport are also more impressive -
300,000 yds. at Shinnecock Inlet, 350,000 yds. at Moriches Inlet,
600,000 yds. at Fire Island Inlet, and 550,000 yds. at Jones
Inlet. The impact of longshore transport on inlet migration
and spit formation is dramatically shown by a comparison of
historical surveys of Fire Island Inlet. The present location
of the inlet is 4.6 miles to the west of the position it occu-
pied in 1825.(7)
Changes in the position of a shoreline can be grouped accord-
ing to their time scale. Short-term beach changes (measured in
hours or days) result from normal tide and wave action or the oc-











curence of storm events. Intermediate changes (measured in months)
result from the normal seasonal alterations in shoreline configu-
rations represented in summer and winter beach profiles. These
seasonal changes are very apparent along the Island's south shore.
Long-term changes in the position of the shoreline that occur over
a number of years or decades are of primary concern in the develop-
ment of planning recommendations. Such changes reflect the net
effects of the intermediate and short-term processes. Surveys on
long-term trends in the position of the high water shoreline have
been made for the south shore.(4)
Shoreline trend data has been summarized in this paper by the
use of aplot showing net erosion/accretion rates versus shoreline
distance for selected locations. Such plots are useful in making
general comparisons between different shoreline areas. More de-
tailed analysis, with particular attention to the evaluation of
causal factors, is required for evaluating trends on a local basis.
A quick glance at the plot reveals areas that have accreted (ap-
pear as peaks) or eroded (appear as troughs) during the historical
period referenced. Water distances, e.g., at inlets, are not shown
to scale on the plot.
The south shore has numerous areas of accretion and erosion
as shown in Figure 1. The rates of both accretion and erosion are
significant. This is due to the changing form of the barrier is-
lands over time and the influence of tidal inlets on erosion/
deposition patterns; rates at inlet areas are not shown in the plot.
For most of the south shore, rates are shown for two periods
of record: 1838-1933 and 1933-1956. For the earlier period, rates
of erosion generally vary between 2-4 ft./yr. The influence of
tidal inlets is reflected in the erosion rates of 10 ft./yr. or
greater to the east of Gilgo Beach. Three prominent areas of ac-
cretion are shown. The accretion at the Davis Park area and the
area to the west of Gilgo Beach may be the result of shoreline
straightening and inlet filling. The accretion at the Napeague
Beach area is due to the filling of a gap in the Ronkonkoma mo-
raine by littoral drift.
The rates shown for the latter period, 1933-1956, are greater
in magnitude and more variable over a given shoreline distance.
This is probably due to rate calculation based on a shorter period
of record, the occurrence of two catastrophic hurricanes (21 Sep-
tember 1938 and 31 August 1954), and man-induced erosion. The man-
induced erosion was caused by the stabilization of Moriches and
Shinnecock Inlets. The stabilized inlets trapped significant
quantities of littoral drift, resulting in the starvation of
beaches downdrift on Fire Island and Westhampton Beach. Erosion
rates to the west of both inlets were typically 10 ft./yr. or
greater during this period. During the earlier period (1838-1933),
there were no tidal inlets open east of Fire Island Inlet.














































_

o 2















--1933-1951-9 319 6 th i led


















WATE AREAS NO1 TO SCALE
or i









figure I Erosion snd Accretion Rates, South Short of Long Island (based on profile data contained in Taney, 1961)












Recent observations of shoaling within Shinnecock Inlet and
erosion rates on nearby downdrift beaches indicate that more lit-
toral drift is supplied to the west as the inlet shoals grow and
the efficiency of natural sand by-passing increases. This re-
duces the erosion rate. Dredging in the inlet to remove the shoals
can be expected to reduce natural sand by-passing and increase sand
entrapment. Estimates of the amount of littoral drift trapped by
inlets each year along the south shore are 150,000 yds. Shinne-
cock Inlet, 250,000 yds. Moriches Inlet, 400,000 yds. Fire
Island Inlet, and 450,000 yeds. Jones Inlet.(8) This points to
the importance of inlet conditions as a factor in determining
erosion/accretion of south shore beaches. Where sand by-passing
accompanies the dredging and stabilization of inlets, utilization
of downdrift beaches as a source of sand for longshore transport
can be reduced, thus minimizing man-induced erosion.
In recent years beach stabilization, bluff erosion, and prop-
erty development along Nassa-Suffolk shores have become controver-
sial issues, generating social, economic, legal and political
differences. A sense of the irony in the term "development," the
widespread expectation that the shoreline will for some reason
stand still after it's been built on, the rude awakening for de-
velopers, houseowners, and commercial builders when they discover
the shoreline is not static all are part of a shoreline "con-
sciousness-raising" that has been making painful headway. In
addition, the potential for storm-induced erosion damage has
increased greatly in recent years because of shoreline construc-
tion activity in the late 1960's and the 70's. Perhaps this con-
struction activity has been spurred by a false sense of security
arising from the absence of major damage producing hurricanes and
northeasters impacting the Long Island region during this time
period.(9) Indeed, many Long Island residents have had little or
no experience with the effect of storm surge and winds resulting
from a major hurricane.
The U.S. Army Corps of Engineers appraised coastal shore
erosion problems in its National Shoreline Study.(3) Two hundred
seventy nine miles of shoreline in the bi-county region have been
designated as critically eroding. In these areas, the rate of
erosion and character of development justify the use of beach
nourishment or the construction of shore protection devices to
alleviate the erosion problem. The estimated first cost for shore
protection in the form of beach nourishment for the critically
eroding shores is over $300 million. This estimate does not in-
clude the price of annual beach nourishment for maintenance pur-
poses.
Although Nassau-Suffolk total shoreline mileage is only about
half a percent of the total national shoreline mileage, over 10%
of the nation's critically eroding shores are found in the area.
All of the south shore is classified as critically eroding.













Nassau-Suffolk has the distinction of having more critically erod-
ing shoreline, where erosion is likely to endanger life or public
safety, than any coastal state.
Damages from shore erosion include the loss of beaches used
for public and private recreation, the continuing loss of water-
front land, and substantial damage to highways, residences, com-
mercial development, and other waterfront structures. The dollar
magnitude of these damages is substantial, especially where shore-
line areas have been subject to intense use and development. For
the south shore of Long Island, the National Shoreline Study stated
that shoreline regression results in the loss of from one-half acre
to one acre of unprotected beach per mile of shore. Dollar losses
due to land erosion amount to $7,000 $50,000 per mile of shore
per year. The total land losses for the 120 mile shoreline exceed
$1 million annually. When combined with estimates of structural
damage, increased highway maintenance, etc., total annual damages
along the south shore are estimated at about $9 million (about
$85,000 per mile of shore). Estimates of erosion costs from land
loss, repair and maintenance of shore protection devices, and shore
cleanup for New York's Long Island Sound shoreline have been esti-
mated at $4.4 million annually.(2)
The high cost of shore protection is not the only problem
facing the shore home or business owner, the park superintendent,
and the government official. When structures such as groins or
jetties are built, the configuration of the shoreline is changed.
This altered shoreline still remains subject to natural forces;
winds, waves, tides and runoff establish new conditions of shore-
line equilibrium. In all cases, this change has not been to the
benefit of man. Unwanted erosion or accretion may result, es-
pecially in areas adjacent to the sites of the structures. Such
is often the case when shore protection structures, which are in-
herently dependent on the dynamics of the littoral zone to perform
their intended function, are built without enough knowledge of the
littoral processes affecting the shore. There are numerous exam-
ples in the literature cited in this report that illustrate the
beneficial and adverse effects of shore protection both in terms
of magnitude and length of shoreline affected.

Extant Solutions

A plethora of plans, programs, projects, and regulations have
been put forth by every level of government to the extent that the
overlapping and often conflicting proposals constitute a problem
by themselves. The U.S. Army Corps of Engineers has seven pro-
jects in varying stages of completion, and an additional study.
These projects include shoal and channel dredging, dike and jetty
constructions and extensions, groin construction, vegetation
placements, and sand by-passing installations. The policies of











the National Park Service pertaining to erosion control within the
Fire Island National Seashore reflect the desire to preserve the
serenity and natural beauty of the barrier beach, while providing
for lower levels of usage than accommodated at other shoreline
parks under other jurisdictions. Thus, the Seashore policy is
based on a desire to minimize interference with natural shore pro-
cesses, and, in some instances, is diametrically opposed to Corps
authorized project recommendations for the same beach.
The Federal government makes a further input into the some-
what confused situation by the administration of the National Flood
Insurance Act (P.L. 90-488) under the aegis of HUD's Federal In-
surance Administration.
This program provides flood insurance protection to previously
uninsured property owners in flood prone areas. Flood-related
erosion protection was added to the National Flood Insurance Pro-
gram by the Flood Disaster Protection Act of 1973 (P.L. 93-234).
Through the Flood Insurance Program, the Federal government seeks
to reduce flood disaster losses through flood plain management
measures, which encourage or require property owners to locate
outside flood hazard or flood-related erosion prone areas, or to
elevate or flood-proof their homes and businesses to reduce flood
or flood-related erosion damage. Structural or non-structural
methods can be employed in floodplain management. Structural
methods include bulkheading, diking, damming, etc. Non-structural
methods include the enactment of setback requirements, zoning and
subdivision controls, the acquisition of open space, etc. Ironi-
cally, coastal flood hazard areas are desirable for residential
and recreational purposes. Investigations have shown that a large
proportion of homeowners occupying coastal flood hazard lands would
rebuild their homes in the same location if wiped out by flooding.
(10) It is necessary therefore to ask whether federal policy acts
as an incentive or disincentive to locate outside flood hazard
areas. Presently, owners whose structures are damaged substan-
tially beyond repair by flooding may choose to relocate outside
the flood hazard area. In choosing to do so, however, the owner
will receive coverage based on the depreciated value of the
structure as settlement on the claim. Should the owner choose to
rebuild on the same site, the claim will be paid in full up to
policy limits. This disincentive would appear to be counterpro-
ductive to Congressional intent as expressed in the National
Flood Insurance Act of 1968 as amended. This apparent inconsis-
tency can be resolved by requiring the Program to provide full
replacement coverage on structures damaged substantially beyond
repair by flooding, should those insured decide to relocate out-
side flood hazard areas.
The State of New York is also active in erosion control by
providing supplemental funding and directly by initiating projects
to protect state properties. The Department of Environmental Con-












servation assists shore protection construction by funding up to
70 percent of the local share for authorized federal projects, and
up to 70 percent for state projects built at the request of local
government, which must contribute the remaining 30 percent. There-
fore, on major federal erosion control projects for which the
Federal government provides 70 percent of total project costs, the
State of New York could contribute up to 21 percent of total pro-
ject costs. The remaining costs nine percent would have to be
provided by local government.
The Long Island State Park Commission (LISPC) is responsible
for management and maintenance of New York State Parks in Nassau
and Suffolk Counties. The LISPC has implemented a terracing and
planting project to forestall bluff erosion at Montauk State Park
and is investigating the feasibility of using a cut-off ditch to
intercept stormwater runoff before it erodes the face of the bluffs
at Camp Hero.
Storms have eroded the primary dune line along the Jones Beach
barrier island. Parking field #9 has been abandoned for over two
years after repeated beach nourishment projects have failed to main-
tain adequate beach widths. Corps of Engineers sand by-passing and
beach nourishment projects have, however, been successful along
other sections of the beach. Should new inlets breach either
Robert Moses or Jones Beach State Parks, the LISPC would close the
inlets artificially in order to maintain access to the parks via
highway. As a further protection to the beach, the LISPC prohibits
both pedestrian and vehicular traffic over dunes and the destruction
of beach grass and natural vegetation.
The Counties exercise regulatory and operational functions
that often conflict with both the Corps and the Seashore. For
example, Suffolk County park policy differs from that of the Sea-
shore, both in respect to recreational usage and erosion control.
The park department pursues active intervention in order to main-
tain the higher levels of usage characteristic of the county parks.
The County Executive, however, is adamently opposed to groins and
has successfully blocked the completion of the Westhampton groin
project.
Municipalities are also active, particularly in maintaining
regulatory controls over the location, density and types of land
uses on the barrier beaches. They also initiate and control dune
ordinances, and to a lesser extent, conduct restoration programs.
Enforcement though is spotty and little correlation exists in the
policies and practice of the separate jurisdictions.
The following sections discuss in greater detail the impact
of such uncoordinated approaches on Westhampton Beach and the
Seashore.











Groins To Be or Not


The New England Hurricane of 1938 struck the south shore of
Long Island less than 10 miles west of Westhampton Beach at about
2:30 p.m. on the afternoon of 21 September about 3.5 hours before
the predicted high tide. Travelling at a forward speed of 60 miles
per hour with sustained wind speeds of over 80 miles per hour (an
extreme gust of 186 miles per hour was recorded in Massachusetts),
this storm produced waves 10 to 12 feet high along the south shore
on a storm surge, or increase in the stillwater elevation of the
ocean in excess of that caused by normal tides, of 10 feet. In a
few hours, the waves and surge of this hurricane leveled sand dunes
on south shore beaches up to 30 feet high that had taken a century
to build. Eight inlets were cut in the barrier bar in the vicinity
of Westhampton Beach (only one inlet Shinnecock remains open
today). Overwash fans deposited in the bay adjacent to the breaks
in the bar nearly filled the Intracoastal Waterway channel. How-
ever, impacts other than those relating to geomorphology were of
greater concern to the residents of the region. Forty-five people
were killed in the storm; many more lives probably would have been
lost had the hurricane occurred a few weeks earlier before the end
of the summer vacation season. One thousand houses were damaged
or destroyed between Fire Island Inlet and Southampton. At West-
hampton Beach 24 people lost their lives (seven additional people
were reported missing) and 150 homes were destroyed.
What would happen if another '38 hurricane (a 40 year storm)
hit the south shore of Long Island today? The loss of life prob-
ably would not be as great because of better advance warning of
the storm's approach, but because of the extensive residential/
resort related growth that has occurred along the shoreline
between Fire Island Inlet and Montauk Point during the last gener-
ation, physical damages would be tremendous.
State and local beach stabilization efforts at Westhampton
Beach after the occurrence of the '38 hurricane were limited to
dune rehabilitation through sand fencing and planting American
beach grass and the construction of jetties and revetments at
Moriches and Shinnecock Inlets. Damage to the barrier and prop-
erty continued, however, as a result of hurricane Carol in 1954
and the East Coast Atlantic Storm of March 6-8, 1962. As a result
of the latter storm, the area was declared a national disaster.
The U.S. Army Corps of Engineers was asked by New York State
to study the problem of erosion control along Long Island's Atlan-
tic Ocean shorefront in the mid 1950's. In 1960, the Fire Island
Inlet to Montauk Point Beach Erosion Control and Hurricane Pro-
tection Project was authorized by Congress. This project pro-
vided for: widening the beaches along developed areas between
Kismet and Mecox Bay to a minimum width of 100 feet at an eleva-
tion of 14 feet above mean sea level; raising the 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; planting grass on the dunes; constructing interior drain-
age structures at Mecox Bay, Sagaponack Lake, and Georgica Pond;
construction of not more than 50 groins, if needed; and Federal
participation in the cost of beach nourishment for a period not to
exceed ten years from the year of completion of a useful nourish-
ment unit. The estimated total cost of the project was $137,864,000
of which the Federal share is estimated at $91,180,000, and the
estimated annual cost for nourishment is $846,000 of which the
Federal share was estimated at $70,000 (October 1976 price level).
(11)
To date most construction activity of this project has oc-
curred in Reach 2 Moriches Inlet to Shinnecock Inlet, which in-
cludes the Westhampton Beach area. Because this erosion control
work involves political, social, economic, engineering and environ-
mental issues, it has become the most controversial coastal pro-
tection project in the Long Island region.
With the support of County Executive H. Lee Dennison and the
Suffolk County Board of Supervisors at the local level in the 1960's,
two segments of work were completed in Reach 2. The first segment -
construction of 11 groins at Westhampton Beach was completed in
October 1966 at a cost of $2,334,955. Contrary to original Corps
plans, the groins were not constructed in sequence from west to
east, starting at Moriches Inlet, nor were the groin compartments
filled. The change in construction schedule resulted from several
factors, including strong homeowner pressure for immediate relief
at the eastern end of the project. Since it was assumed that the
entire project would be finished, the change did not seem impor-
tant at the time. The predictable result increased erosion down-
drift of the groin field and subsequent damage to private and
municipal property occurred. Affected property owners pressed
public officials for relief.
A second segment, completed in November 1970 at a cost of
$3,663,455, involved the construction of four additional groins
and the placement of 6,000 feet of dunes and beach fill west of
the original 11 groins. Even though these groin compartments were
filled, the impacts of inlet stabilization at Moriches and Shinne-
cock without sand bypassing and the interception of longshore drift
in the unfilled groin compartments again caused insufficient natu-
ral nourishment of the beach to the west of the four new groins.
Again, man-induced erosion downdrift from the extended groin field
becomes a serious problem. Support was generated for the construc-
tion of an additional six groins to complete original plans for
the stabilization of Westhampton Beach and to prevent creation of
a new inlet to Moriches Bay.
However, the policy of Suffolk County regarding financial
participation in erosion control projects changed dramatically











with the election of County Executive John V.N. Klein in 1972.
Mr. Klein's posture was one of non-interference with natural shore-
line processes, and hence, he has consistently opposed the con-
struction of additional groins at Westhampton Beach. The 18-member
Suffolk County Legislature, which replaced the Board of Supervisors
in 1970, has often been at loggerheads with Mr. Klein over County
participation in erosion control projects. Heikoff describes in
detail the intergovernmental relations and technical considerations
involved with this project and the construction of the 15 groins at
Westhampton Beach.(12) Many technical considerations were ignored
in arriving at policy decisions to reduce project costs. The ulti-
mate cause of the man-induced erosion problem is, according to
Heikoff, failure to complete the Corps project as initially designed.
Today, an extremely serious erosion problem persists to the
west of the existing groin field. Extensive damage to development
and a breach in the barrier occurred here as a result of the severe
1978 winter weather. The problem is exacerbated by unstable shore-
line conditions at Moriches Inlet. Scouring along both bay and
ocean shores has narrowed the barrier adjacent to the east jetty to
such an extent that the jetty may be outflanked in the near future.
An emerging nourishment project financed by Suffolk County may fore-
stall this event for a short period of time.
The Long Island Regional Planning: Board has developed stra-
tegies for erosion control along the Long Island shoreline as part
of its Coastal Zone Management Program. The strategies for the
south shore are outlined below(13):
Accept the natural, long-term shoreline regression that is
occurring along the headlands section of the south shore as
a phenomenon that is beyond man's present capability for
practical, effective control. Emphasize non-structural
solutions to coastal erosion problems here.
SStabilize the south shore inlets (Shinnecock, Moriches, Fire
Island, Jones, East Rockaway) at approximately their pre-
sent locations and implement sand by-passing programs. New,
natural inlets that breach the Long Beach, Jones Beach, Fire
Island and Westhampton Beach barrier islands and the South-
ampton barrier beach as a result of severe storms and/or
shoreline regression should not be maintained. If longshore
transport does not repair a natural breach, steps should be
taken to close it artificially.
SArtificial manipulation and public investment designed to
stabilize the Atlantic Ocean shoreline along Fire Island
and the Southampton barrier beach should be minimized.
Maintain the general position and configuration of the
Atlantic Ocean shoreline along the entire south shore of
Nassau County, and along that portion of the Jones Beach
barrier island located within Suffolk County. The Atlantic
Ocean shoreline along the Westhampton barrier island should
also be maintained.












To foster these strategies, the Board recommends that the
County and State support (both morally and financially) the autho-
rized federal projects for improvement of Shinnecock and Moriches
Inlets, including installation of sand by-passing programs. Most
of the Fire Island Inlet to Montauk Point Beach Erosion Control
and Hurricane Protection project should not be implemented as
authorized, with the exception of a modified nourishment program
for the central and western end of the Moriches Inlet to Shinnecock
Inlet Reach. To maintain the general shoreline configuration of
the Westhampton Beach barrier island, the existing 14 groin compart-
ments should be filled as appropriate, and fill should be added to
restore that section of the beach immediately to the west of the
existing groin field, which is in jeopardy of inlet breaching. The
combination of sand by-passing at Shinnecock Inlet and filling the
existing groin field may restore the net rate of longshore trans-
port along the Westhampton Beach barrier island to that which
existed prior to stabilization of the beach and Shinnecock Inlet.
The New York District of the Corps has completed preliminary
planning for filling the groin field and nourishing the downdrift
beach. About 8 million yds. of fill will be needed. The fill will
be obtained from offshore borrow sites. Total costs amount to about
$20 million of which the County share would be about $1.8 million.
The Corps appears to be waiting for State and local initiative on
this aspect of the project. Political aspects again arise:
"The Corps assumes leadership in the coordination of project
plans and in obtaining required local cooperation to imple-
ment a Congressionally authorized project. Since authoriza-
tion of the Fire Island Inlet to Montauk Point Project,
however, the opinion of Suffolk County has frequently varied
between opposition and approval. The project is sufficiently
extensive and complex that frequently only one small element
of the project is desired by the County at any particular
time: for example, the next increment of work at Westhampton
Beach. For this reason we have given responsibility for the
initiation of construction to local interests. In other
words, we will not undertake further construction on the
project unless requested by the State and County."(14)
Thus, despite decades of study, imminent potential hurricane
destruction, and general agreement that coastal protection must
be assured implementation remains mired in political contro-
versy.

The Fire Island National Seashore (FINS)

The Long Island Regional Planning Board, in the development
of its Coastal Zone Management Plan, has emphasized non-structural
approaches in dealing with coastal protection problems, wherever
feasible. A number of planning guidelines were developed to











assist local governments in the formulation of public policy and
decision-making. The guidelines are helpful to planning commis-
sions in their review of subdivision design and in municipal
planning, to zoning boards in their formulation and amendment of
zoning ordinances and building codes, and to conservation advisory
councils in their review of both public and private development
projects to assure the maintenance of an aesthetic balance between
man and the natural environment. Government agencies in charge of
projects which can have significant effects on coastal resources
should use the guidelines during the design phase of such activi-
ties to lessen possible adverse environmental impacts. Table 1
summarizes the major recommendations.(15)
In particular, coastal construction setback lines were pro-
posed for controlling the location of new development along
eroding shoreline areas. Two coastal erosion hazard zones were
defined by the setback lines:
a. bluff and coastal dune hazard zone the area seaward of
a line located 100 ft. landward from the top edge of a
coastal bluff or headland, or the top of the seawardmost
rank of coastal dunes.
b. barrier island and barrier beach primary dune hazard zone -
the area seaward of a line located 40 ft. inland from the
14 ft. elevation contour on the landward flank of the
primary dune; or where applicable, oceanfront areas where
primary dunes are absent or are lower than 14 ft. in
elevation, including historic overwash areas.
The latter setback recommendation was considered by the National
Park Service (NPS) in the development of the General Management
Plan for the Seashore.(8) The philosophy expressed in their plan
is compatible with it. Table 2 summarizes the general management
policies.
Although the Board's barrier island primary dune hazard zone
is more restrictive than the FINS dune district, the power and
intent of FINS to condemn and purchase properties (given Con-
gressional appropriations) located within the district more than
compensate for the difference and should provide protection of
Fire Island primary dunes from adverse structural development.
Another proposed FINS policy currently before the Senate con-
cerns the acquisition of property within the 17 exempted communi-
ties following major storm damage. The FINS General Management
Plan proposed a legislative amendment to permit the NPS to acquire
private lands within exempted communities if major storm activity
destroys 90 percent or more of all structures within a community,
and damage to each structure is in excess of 50 percent or more of
its fair market value. Lands where structures were destroyed
would be acquired in fee by the NPS. Structures that were not de-
stroyed would remain in private ownership as inholdings exempt
from condemnation. These properties would not be acquired unless








TABLE 1: SUMMARY OF PLANNING GUIDELINES FOR COAST STABILIZATION AND
PROTECTION (15)

1. Control development on those lands contained in the InteAmediate Regional
Tidal Flood PZain* by use of Zlood plain zoning, land use management concepts
and other regulatory tools. Uses other than those requiring shorefront loca-
tions and those related to recreation, as well as the expansion of existing
uses, should be discouraged. Non-conaotming u6e status should be applied to
existing development. Necessary future construction on the flood plain should
be located in accordance with the establishment of sufficient set-back tines,
so as to avoid damage from short-term shoreline changes. Such construction on
the flood plain should include, as a minimum, elevation of first floors of
such structures above the Intermediate Regional Tidal Flood Plain level, and
floodproofing of utilities and equipment serving such structures. Consult the
National Flood Insurance Program as amended by the Flood Disaster Protection
Act of 1973 for flood plain insurance eligibility, floodproofing, and land use
management requirements.
2. Prohibit construction on ptimary dune lines.
3. Adopt btluf hazard zoning in those shoreline areas, especially along the
north shore of Long Island, which are backed by eroding bluffs. Discourage
construction in the zone 100 feet landward from the top seaward edge of the
bluff defined by an abrupt increase in slope.
4. As a general rule, discourage expenditure of public monies for the design
and construction of shore protection work and beach nourishment on private
lands unless substantial benefit to the public or public lands can be sub-
stantiated.
5. Accept the natural, long-term shoreline regression that is occurring along
Long Island's north shore as a phenomenon that is beyond man's present capabi-
lity for practical, effective control. Maintain heavily used beaches and rec-
reation areas and, when the need exists, establish new beach areas by means of
sand nourishment techniques in locations where historical records indicate
either accretion or low to moderate erosion of the shore. Maintain existing
navigation channels connecting major embayments with the Long Island Sound.
6. Emphasize dune stabilization and beach nourishment techniques, compatible
with natural processes, as the primary means of minimizing storm breaching
of the Long Island south shore barrier islands, and thus protect the environ-
ments of the south shore bays from sudden short-term changes.
7. Prohibit dredging of sand from the outer baA and from any area between the
bar and the beach.
8. Support research designed to develop the required technology for economi-
cal transfer of sand from deep water sources to the shore for beach nourish-
ment purposes.
9. Stabilize existing southshore inlets (East Rockaway, Jones, Fire Island,
Moriches and Shinnecok) at approximately their current dimensions and loca-
tions. Permit drastic changes in the inlet characteristics only when expli-
citly justified by analysis of consequent changes such modifications will pro-
duce in the bays.
10. Advocate the implementation of Federal projects for sand bypassing sys-
tem6 at Shinnecock, Moriches and Fire Island Inlets.
11. Prohibit the construction of gOaintl and other shore protection devices
either by government or private persons unless it can be demonstrated that
such structures will not adversely affect adjacent property.
* Those lands covered by a tide having an average frequency of occurrence on
the order of once in 100 years, although the tide may occur in any year.











TABLE 2: FIRE ISLAND NATIONAL SEASHORE GENERAL MANAGEMENT POLICIES
RELATING TO BEACH EROSION CONTROL AND PRIMARY DUNE PROTECTION(8)

1. Encourage the immediate installation of the authorized sand by-
pass systems at Moriches and Shinnecock Inlets.
2. Recommend spoiling sites for material dredged from Shinnecock,
Moriches and Fire Island Inlets, and from the Intracoastal Water-
way to the Corps of Engineers.
3. Prohibit the artificial opening of new inlets within Fire
Island National Seashore boundaries. Should new inlets open
naturally, they will be evaluated. If adverse impacts outweigh
benefits, new inlets may be closed by the Corps of Engineers.
4. Assess sand nourishment proposals. As a general principle,
dune construction and direct beach replenishment will not be
undertaken in the large Federal tract east of Watch Hill. How-
ever, if research and analysis of environmental impacts show that
man's intervention is essential for perpetuating the barrier and
its natural resources, such activities may be undertaken.
5. Prohibit the installation of additional groins, bulkheads,
revetments and other artificial beach stabilization devices
(existing inlet jetties are exempted). Permit snow fences for
stabilization purposes in areas where vegetation is sparse, rapid
erosion is occurring and where dune buildup is desired.
6. Repair and restore ocean-facing dunes as needed. Planting
with native perennial dune stabilizing species to encourage re-
vegetation will be initiated throughout the Seashore. Dune blow-
outs and other naturally occurring bare sand areas will be repaired
and replanted when compelling considerations, such as threat to
development, dictate such action.
7. Refrain from disturbing washovers in the natural areas of the
Seashore because washovers aid in perpetuating the barrier island
system.
8. Establish a dune preservation district extending landward for
a distance of 40 ft. from a line representing the primary natural
high dune crest as determined from November, 1976 aerial survey
maps. Such a district will include the primary dune system, or
the primary dune area if no dunes exist. The seaward limit of
the district is the mean high water mark. Future use of the dune
preservation district will be severely limited. No new structural
development or stabilization devices other than snow fences will
be permitted. Elevated dune crossings for pedestrian-and essen-
tial vehicles will be allowed. The approximately 250+ unimproved
properties included within the dune district will be acquired,
when necessary, to prevent development from occurring. The struc-
tures on the other 257 improved properties in the dune district
will be permitted to remain indefinitely unless they are damaged
by storms in excess of 50 percent of their fair market value.











they too were destroyed by a storm at some future time.
Property owners within the exempted communities vigorously
responded to these proposals. More than 1000 letters opposing the
amendments were received by Senator Jacob Javits (R.-N.Y.) George
Biderman, Chairman of the original Fire Island Seashore Committee,
and an affected homeowner, raised the sole voice of support. He
contended that the ultimate good must include the maximum expan-
sion of the Seashore. Such altruism is rare indeed. The Long
Island Regional Planning Board subsequently added its support for
the amendments. The Board indicated that the Senator was unduly
sensitive to a letter-writing campaign, especially where the
interests of millions of citizens are concerned.
Actually, the situation is a tempest in a teapot. The amend-
ments do not go far enough. Even the 1938 hurricane did not destroy
90 percent of all structures. The basic problem originated with
the vacillation on the part of Congress in adopting the 1964 legis-
lation which established the Seashore. They yielded to local pres-
sure and exempted communities within the proposed boundaries of the
Seashore. They could have set a specific tenure to cater to the
desires of the seasonal property owners after which the properties
would be subject to condemnation.
The outcome of this debate may well set the tone for the future
of the Seashore.

Conclusion

The politics of erosion control is simililar to many public
policy debates. Implementation does not occur solely on the basis
of technical rationality. Regardless of the severity of the ero-
stion problem, or the technical merits of proposed solutions, imple-
mentation involves mediation between diverse groups and individuals
who seek to influence land use and environmental decisions. Thus,
erosion control must be understood to be funadmentally a political
activity. It is political in the following ways: it is a govern-
mental process presumably set up to formulate and execute policy on
erosion activities. Administratively, erosion projects are primar-
ily governmental in concept and execution. The interactions between
public agencies and private citizens require mediation and compro-
mise the very essence of politics.
This reality is not necessarily negative. Politics herein, is
held to be the conduct of the public business in non-partisan fash-
ion, or perhaps more accurately stated, multi-partisan. However it
is viewed, implementation of erosion control will be more success-
ful if it is conducted with the public involved, rather than for
the people.











REFERENCES


1. Allen, Everett S., 1976. A Wind to Shake the World. Little,
Brown and Co., Inc., New York, N.Y.

2. Koppelman, Weyl, Gross and Davies, 1976. The Urban Sea: Long
Island Sound. Praeger Publishers, New York, N. Y.

3. U. S. Army Engineer Division, No. Atlantic Corps of Engineers,
1971. National Shoreline Study Regional Inventory Report,
North Atlantic Region, Vol. 1. North Atlantic Div., New York.

4. Taney, N.E., 1961. Geomorphology of the South Shore of Long
Island, N. Y. Beach Erosion Board TM 128. U.S. Army Corps of
Engineers, Washington, D. C.

5. Shepard, Francis P., 1973. Submarine Geology, 3rd edit.,
Harper & Row, New York. pp. 111-121.

6. Clark, John R. and R. Turner, 1976. "Barrier Islands: A
Threatened Fragile Resource," August 1976 edition of the
Conservation Foundation Letter, Conservation Foundation,
Washington, D. C.

7. Wolff, Manfred P., 1975. "Barrier Island Accretion Features,
Democrat Point, Fire Island," pp. 73-88 in Guidebook to Field
Excursions, 47th Meeting of the New York State Geological
Association, Manfred P. Wolff, ed. N.Y.S. Geological Assn.,
Syracuse, N. Y.

8. U. S. Dept. of the Interior, National Park Service, 1977.
General Management Plan Fire Island National Seashore, NPS
876B. National Park Service, Denver Service Center, as a-
mended by addendum dated March 1978.

9. Nersesian, Gilbert, 1974. "Federal Beach Erosion Control
Activities on Long Island," pp. 73-107 in Proceedings of the
Seminar on Dredging and Dredge Spoil Disposal and Coast
Stabilization and Protection, Regional Marine Resources
Council, Hauppauge, N. Y.

10. Miller, H. Crane, 1977. "Coastal Flood Hazards and the
National Flood Insurance Program." Paper prepared for
Federal Insurance Administration, Dept. of Housing & Urban
Development, HUD Purchase order 1442-77.











11. North Atlantic Division, Corps of Engineers, 1977. Water
Resources Development in New York. U. S. Army Corps of
Engineers, New York, N. Y.

12. Heikoff, Joseph M., 1976. Politics of Shore Erosion:
Westhampton Beach. Ann Arbor Science Publications, Inc.,
Ann Arbor, Mich.

13. Nassau-Suffolk Regional Planning Board, 1978. A Coastal
Erosion Subplan for Nassau and Suffolk Counties. Report
prepared for N.Y. State Department of State under Contract
D125991. Hauppauge, N. Y.

14. U.S. Army Engineer District, New York, 1977. Final
Environmental Impact Statement for Fire Island Inlet to
Montauk Point, New York, Beach Erosion Control and Hurricane
Protection Project. Vol. 1. (with amendments dated May 1978).
U.S. Army Corps of Engineers, New York, N. Y. p. 13.

15. Regional Marine Resources Council, 1973. Guidelines for
Long Island Coastal Management. Nassau-Suffolk Regional
Planning Board, Hauppauge, N. Y.




























NATURE ASSISTED BEACH


ENHANCEMENT


Morton Smutz
Mark E. Leadon
John Griffith
Yu-Hwa Wang
Coastal and Oceanographic Engineering Department
336 Weil Hall
University of Florida
Gainesville, Florida 32611













ABSTRACT


NABE (Nature Assisted Beach Enhancement) is proposed as a
technique for enhancing a sandy beach by using the forces of
nature to bring additional sand ashore. Laboratory tests have
shown that under certain conditions additional sand can be
brought ashore by allowing the beach to come to an equilibrium
state several times following successive berm removals. It is
proposed that the additional sand be moved to the dune area
and stabilized by vegetation.










INTRODUCTION


The ever-changing nature of a beach is well known. In "Beaches
and Coasts," by King and McKay (1) state "A beach is one of the most
variable land forms; it can be there one day and gone the next."
Johnson (2) states, "In the first place, it must be borne in mind
that the beach is merely a temporary deposit, slowly making its way
to deeper water."

Methods employed to date to maintain and enhance beaches
include (1) devine supplication, (2) construction of jetties and
groins, (3) establishment of construction control lines, and (4)
artificial beach nourishment. The latter method is generally
accepted as the surest and quickest way of reestablishing a beach
once it has disappeared. It would be good if a method could be
found to achieve the same objective by a natural beach nourishment
technique.

Inman and Bagnold (3) describe the migration of sand grains
by bed-load transport and develop an equation for the average
migration speed. Yalin (4) provides a rigorous discussion of
suspended-load transport. Komar (5) reviews these two methods and
concludes that bed-load transport will normally dominate over
suspended-load transport.

It has long been recognized that so-called sumner (or swell)
beach profiles differ from winter (or storm) beach profiles.
Extensive laboratory and field studies have been conducted on both
sand transport directly to-and-from the beach and along the beach.
Tanner (6) has introduced the concept of an equilibrium beach where
there is a balance between the forces tending to bring sand to and
from a beach.

Figure 1 shows the general features of a beach. Special note
should be made of the berm which is defined as the near horizontal
portion of the beach formed by the deposition of sediment by the
receding waves. The breaker zone is the portion of the nearshore
region where the incoming waves become unstable and break.

Pilkey and Field (7) made a thorough study of the onshore
transport of sediment from the continental shelf off the south-
eastern Atlantic coast of the United States and concluded that
beach and estuarine sands "are derived in part from the adjacent
continental shelf." King and Williams (8) carried out tank tests
under a variety of wave and beach slope conditions and concluded
that the transport of sand seaward of the breaker zone was always
toward shore. Shoreward of the breaker zone the direction of
sediment movement depended on the test conditions.


















-200' -- 220' 150'
24


20 ..-..








8
16 .. .



.. .' .* Storm Tide Level



S. Mean Low Tide I *
0
0 60 120 180 240 300 360 420 480 540 600

Beach Length (Ft.)


Figure 1








A criteria for determining when the net transport of sediment
would be toward the shore has been shown to be the ratio of wave
height to wave length. The exact relationship depends upon the
scale of operation, grain size and other factors. Dean (9)
approached the criteria on the basis of sediment settling velocity
and found that his method correlated the data of 189 experiments
with 89% consistency. Per Bruun and Gunbak (10) discuss the
influence of wave period and slope angle to the stability of
permeable and impermeable sloping-faced wave-protection structures.
The principles obviously apply to sandy beaches which are nature's
structures that protect the land from further intrusion by the sea.

In summary of previous work, for sandy beaches like those in
Florida, large quantities of sand move to and frcm the beach area
in response to the characteristics of the waves and currents. The
transport is opposed by the force of gravity and resistances
encountered by the sea bed and beach area. When these forces are
in balance, a steady-state or near equilibrium condition results.
Under conditions favorable to accretion of sand and when the con-
trolling resistance to accretion is the slope of the beach, it
should be possible, in principle, to accumulate more sand on the
beach by altering the slope.
NABE

Nature Assisted Beach Enhancement (NABE) is a proposed means of
enhancing or maintaining a beach by using the forces of nature to
bring additional sand to the beach. The principle of the technique
is quite simple. Under conditions that favor the movement of sand
to the beach, the slope of the beach is altered to encourage more
sand to accumulate. The additional sand can then be moved to the
dune area and appropriate vegetation planted to stabilize it.

Skeptics of the concept are quick to point out that there is
only a finite amount of sand in the system and, if one beach area
benefits, it must be at the expense of sand supply in another part
of the system. Bowen and Inman (11) provide scme indirect evidence
that this may not be a serious problem. They found that it was not
possible to estimate the amount of sand accumulated on a beach by
measuring the changes that occurred in the offshore bathymetry
because the changes were so small and the area was quite large.

LABORATORY TESTS

Three series of runs were made to determine (1) whether or not
it was possible for us to demonstrate in the laboratory that an
equilibrium beach could be obtained, (2) whether or not it was
possible to accumulate more sand on the beach by the NABE technique,
and (3) the mechanism by which the sand moves from offshore to the








berm area. Figure 2 is a photograph of the basin used in the first
two series of runs. Figure 3 is a photograph of the basin used in
the third series.

Table I shows the values of the test variables for each series
of runs.

APPROACH TO STEADY STATE

At the beginning of the experiment the sand (0.2rm average
diameter) was smoothly distributed throughout the basin with a
uniform beach slope. As soon as the wave maker was turned on, ripples
began propagating seaward and beach berm began to form. The ripples
eventually filled the entire basin and the berm grew to full size. A
near steady-state condition developed in about eight hours.

The topography between the upper limit of the wave run-up
and the breaker-line was characterized by (1) a berm with a smooth
surface and a single uniform slope stretching across the basin,
(2) a depression or trough at the foot of the berm, (3) a longshore
bar situated seaward of the trough, and (4) the breaker-line located
a short distance seaward.

As the running time increased various troughs, bars and
depression areas formed offshore. These uneven topographical
configurations were due to the interaction between incident waves
and discrete seaward rip currents. The offshore shelf region
still maintained its slope and general features.

The time required for the model to reach steady state obviously
depends upon how close the starting conditions resemble the final
values. Figure 4 shows the beach profile as a function of time
after five hours when the original beach slope was 1:20.

BERM REMOVAL

In the second series of runs, the beach was allowed to cane to
a near equilibrium state several times following successive berm
removals. Each time the beach reestablished itself when operations
were continued. Data concerning the running time and the amount of
sand removed are shown in Table II.

The variation in the amount of sand removed was due in part
to the difficulty in scraping wet sand to a particular slope.

The 49.3 cubic feet of sand moved to the beach and removed
from the basin in 148 hours of running time by one inch waves
amounts to over three tons of dry sand per week.



















































Figure 2.





















































Figure 3.













94














TABLE I OPERATING CONDITIONS FOR MODEL RUNS.



Run Series 1 2 3


d 7" 9" 36"
o
H 0.75" 1" 2"

L 42" 55" 110"

T 1.4 sec. 1.5 sec. 1.9 sec.

Hb =1.5" =2.0" 2-1/4"

Initial Slope 1 : 20 1 : 24 1 : 14


*Subscript "o" refers

d

H
o
L

T

Hb


to deep water; i.e., near wave paddle

water depth

wave height

wave length

wave period

wave height at break point







0.5




0.4


LL.
,- 0.3-
I
0
I
z 0.2-



o., -
0.1-




0.5 1.0 1.5 2.0

BEACH LENGTH (FT)


Il-


HOURS
5
5 ---------
6 ----
7 ---


3.0


Figure 4


3.5




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