HomeMy WebLinkAbout; ; Beach Erosion; 1994-02-01A LAYMAN'S
GUIDE
TO
BEACH
EROSION
FRANK ALESHIRE
CARLSBAD February 1994
Figure 1
CRITICAL SHORELINE EROSION PROBLEM AREAS
Camp Pendleton
Oceanside
Imperial Beach
MEXICO
Carlsbad
:>
Encinitas
5»
Solana Beach
Mar
'Shoreline Preservation Strategy for the San Diego
Region? Sandag, 1992.-3-
INTRODUCTION
SHORELINE STUDIES
In 1983 the Corps of Engineers began a study of the 85 miles of
coastline between Dana Point and the Mexican Border. The purpose
of the study was to learn what is happening along this coast. The
study produced 41 technical reports and a Final Report in Sept
1991. The entire program is called "Coast of California Storm and
Tidal Waves Study" (CCSTWS) or "COAST OF CALIFORNIA STUDY."
The information in the study was used by SANDAG (San Diego
Association of Governments) in the preparation of a report which
came out in July 1993 entitled "SHORELINE PRESERVATION STRATEGY FOR
THE SAN DIEGO REGION." The report reviews the problems of the
coastline and recommends specific policies and actions for local
government.
The Corps of Engineers reports are highly technical and nearly
impossible for the public to use or to understand. The Sandag
report is more readable but still difficult for the layman. I read
these reports while working with a junior high school student who
was doing a science project on beach erosion. I researched the
local libraries, and materials published by the Corps of Engineers,
Scripps Institution of Oceanography, the Coastal Commission, Sandag
and others and was unable to come up with material suitable for
students. The material available - and there is plenty of it - is
written by engineers and scientists for their own consumption.
It is my belief that one of the responsibilities of government is
to educate the public about complicated issues so that citizens can
know what is going on. What could be more important in San Diego
than an understanding of the beach and its problems? We need
books, pamphlets, reports with pictures, diagrams and cartoons
suitable for school children. Why can't our local beach erosion
commissions dedicate some of their time and effort to stocking our
library with readable material. The Coast of California study cost
over six million dollars of taxpayers' funds. Scripps and others
are spending millions every year studying the ocean. I think some
of that money could be devoted to public information and
development of better educational materials.
The Christophers once said, "It is better to light a candle than to
curse the darkness." So be it. I hope others more qualified than
I will carry on the work of explaining beach erosion in layman's
language.
Shore Zone-
Nearshore
Shelf
Edge
Figure 1.1. Definition sketch of coastal zone nomenclature for coasts
similar to the California coast (from Inman and Brush, 1973).
BEST ORIGINAL
REPORT ON BEACH EROSION
WHAT DO BEACH STUDIES TELL US
The seashore is a rare and important part of the quality of life in
San Diego County. Did you know that our beaches and seacliffs have
been steadily eroding? Did you know that the ocean level is
slowly rising and attacking the land? The Coast of California
Study concluded that beach erosion and property damage will
continue into the future. It recommends that man must do something
to deal with shoreline erosion problems.
What can we do?
Unfortunately it is not easy to change the ocean. But there are
some actions that could protect our beaches and perhaps enhance our
quality of life. Here are some of the things SANDAG suggests that
we consider doing:
1. Nourish and rebuild eroded areas by putting
large amounts of sand on the beach.
2. Build structures to dampen the waves and hold
sand in place such as groins, seawalls and berms.
3. Develop rules and regulations concerning the use
of the shoreline and construction of urban
developments near the beach.
4. Coordinate shoreline preservation policies between
local, state and federal agencies.
5. Raise the money to carry out the policies and to
manage the shoreline as a benefit to the region's
economy and recreation.
WHAT DO WE REALLY KNOW ABOUT THE OCEAN?
"In the beginning God created the heavens and the earth.
And the earth was without form and void.
And darkness was on the face of the deep...."
Scientists today are studying the record of the earth and trying to
figure out how the earth has grown and changed since its creation.
Most scientists believe the earth was formed from rocks and
metallic fragments left over from the construction of the sun. The
material floating around in space heated up as gravity pulled it
together. As the mass grew larger and hotter the heaviest metals
sank to the molten center. Lighter rocks like granite and lava
floated to the surface forming into layers. Mountains rose on the
surface and formed into continents. Between the continents were
deep and broad lowlands. The lowlands became ocean basins.
The heat of the earth melted rocks and minerals and released gasses
and chemical compounds into the air. Clouds and winds blew across
the planet carrying water vapor. Rains fell onto the hot rocks
forming steam. Rivers flowed down the mountains to the lowlands
filling the ocean basins with sediment and water. From the
beginning the rains and rivers eroded the rocky land and carried
dirt and mud and grains of sand down the valleys to the sea.
Beaches were formed along the edges of the continents. A poem
tells us what happened.
Little drops of rain
Little grains of sand
Ran away together
And took away the land
It is well to remember that what you see at the seashore is not the
rim of the ocean basin. The true ocean begins away off shore where
the edge of the continent dives steeply into the abyss. The surf
you see is shallow. The oceans have an average depth of 15,000
feet (three miles deep). Great waves race across the sea at high
speeds. When these waves approach the shore they are slowed and
compressed by the drag of the bottom and they tumble onto the land.
The energy of waves moves the sand on the beaches, cuts into the
cliffs and constantly pounds and shapes the shoreline.
The shoreline you see is never the same.
Between every wave the beach changes a little.
FRACTALS
The quantum physicists of today call the seashore a "fractal." It
is a place that cannot be precisely measured because it is always
changing. Watch a wave as it rushes up the beach and then retreats
back to the ocean. What is happening? The waves stir up the
pebbles and grains of sand on the beach and toss them about with a
chattering sound. It is like playing musical chairs. All the
grains of sand race around until the wave returns to the sea. Then
each grain settles down in a new place until the music of the surf
begins again.
Listen.
You hear the grating roar of pebbles
which the waves draw back and fling,
at their return, up the high strand.
Begin, and cease, and then again begin.
Sophocles long ago
heard it on the Agean Sea. Matthew Arnold
The scientists are learning that many things in nature cannot be
measured because they are dynamic - always in motion. Clouds are
like that; and the ecosystem of a wetland; and the surges of blood
and air in your body. They are all fractals. Next time you see
the waves and the beach think about fractals. Everything is
changing, including you.
WAVES
What are waves? Think of a puddle of water that is still and
smooth. Toss in a pebble. What happens? A circle of ripples
begins where the pebble hits the water. The ripples spread out in
all directions and smoothly flow outward until the first ripple
waves reach shore where they are reflected backwards. Now the
pattern is not so simple. Waves interfere with each other and form
curious patterns. For awhile the whole puddle is all mixed up.
Then slowly the puddle flattens out and returns to its original
mirror-like calm.
What you see is energy traveling in waves, which bump into each
other and rearrange the molecules of water. It is a simple thing
to do, but even scientists have a hard time explaining exactly what
happens.
Waves are far more complicated in the ocean than in the puddle.
For one thing all the water on earth is influenced by gravity. The
earth's gravity drags water down to the ocean depths. The sun and
moon call to the water and try to pull the oceans away from the
earth. This causes tides that follow regular movements to and fro
across the oceans of the world. And wherever there are tides,
there are waves.
Waves come from many different sources. Winds blow all over the
earth and strike the ocean at many different places. Waves, once
started, often travel clear across the ocean. As they go they bump
into waves that started in other places. Waves are affected by
islands and sea canyons and ships and whales. Storms and
earthquakes often start huge tidal waves that produce fifty to a
hundred foot high crests. When they approach shore they break and
crash, exploding their energy in foam and turbulence that is
awesome to behold.
"As long as there has been an earth, the moving masses of air
that we call winds have swept back and forth across its
surface. And as long as there has been an ocean, its waters
have stirred to the passage of the winds. Most waves are the
result of the action of wind on water. There are exceptions,
such as the tidal waves sometimes produced by earthquakes
under the sea. But the waves most of us know best are wind
waves." Rachael Carson
Questions about the way waves are born, develop, travel and die can
best be answered by oceanographers and scientists who spend their
lives studying these powerful forces of nature.
WHAT IS HAPPENING TO OUR BEACHES?
People who have been around for a long time will tell you about
the wide sandy beaches that used to be along the San Diego coast.
If you walk the shore today you will see that many of our beaches
have lost their sand. Along the Camp Pendelton coast there are
wide, beautiful sandy beaches. There is a lot of sand in Coronado.
But from Oceanside to La Jolla you are more apt to find cobbles and
cliffs and very little sand. How come this is so?
There are three reasons why our beaches are eroding:
1. the ocean level is rising;
2. storms and waves are attacking the land;
3. urban development has cut off the natural flow of sand to the
beaches.
Let's talk about these three things and try to understand the
processes at work along our coast.
OCEAN RISING
"Till the slow sea rise and the sheer cliff crumble,
Till terrace and meadow the deep gulfs drink."
Swinburne
In the past 100 years the sea level off the coast of Carlsbad has
risen by nearly a foot. We are not exactly sure why that is.
Perhaps the polar ice is melting. Perhaps the continent is
sinking into the sea. Scientists expect that the ocean level will
continue to rise in the future and that more of our beaches will
eventually disappear into the sea. The good news is that this is
a slow process and we will have plenty of time to adjust to it.
WAVES AND STORMS
The gentleness of heaven
broods o'er the sea:
Listen ! The mighty Being is awake
and doth with his eternal motion make
a sound like thunder - everlastingly.
William Wordsworth
When you go to the beach, what do you see? The first thing you
notice is how big it is. It is humongous. It goes on, and on as
far as eye can see. The ocean really is the biggest thing on the
face of the earth. Then you notice the waves. They keep coming
on wave after wave after wave. They never stop. They work every
minute of every day and every night. They dance, and surge, and
leap, and crash, and slide, and gush, and rock and roll all over
the place. They seem to have an orderly motion but if you watch
closely they do all kinds of weird things - bounding and swishing
and creating eddies and swirls and turbulence. They are wondrous
to behold.
Every wave is loaded with energy and lots of interesting stuff.
Each wave contains millions of grains of sand, and sea animals, and
shells, and kelp and strange bits of floatsum from the far ocean.
the foaming wave
runnnnns up the beach
slo o o o w s down
unloads.
hurries back
carrying treasures
to the sea again.
All waves do this. They bring things to the beach and take things
away. And somehow amidst all this rushing and churning the ocean
cleans the beach and makes it into the beautiful place we want to
visit.
10
MAP SHOWING RIVERS FEEDING BEACHES, OFFSHORE CANYONS
AND UNDERSEA DEPTHS IN THE OCEANSIDE AREA.
iv \
33°20'H
10"
SCALE IN MILES
SOUNDINGS IN FATHOMS
na°4(r
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118°30'
V \
FIGURE 6-1: LOCATION MAP, OCEANSIDE LITTORAL CELL
11
Waves are seasonal along the San Diego coast. In winter (Oct-Mar)
the ocean current moves from north to south. In summer the current
moves from south to north. In winter the waves are stronger.
They cut the beach and carry sand away. The summer waves are
gentler. They carry sand in and build up the beaches. Some of
the sand that leaves the beaches goes off shore in the winter and
sits beneath the ocean in underwater sand dunes called "shoals."
Then in summer the shoals contribute sand back to the beach.
The ocean acts sort of like a bank account. The summer waves
deposit sand on the beach. The winter waves make withdrawals.
They take the sand away and open a savings account in the offshore
shoals. When summer comes along the waves take sand from the
shoals and deposit it again on the beach. In a normal year the
beaches look the same from summer to summer. The deposits and
withdrawals balance out.
But every so often major storms come along and destroy this
balance. When a big storm hits our coast the waves are violent and
greedy. They gobble up the sand and carry it far out to sea.
Instead of depositing the sand close to shore they dump it in deep
canyons. And it doesn't come back again. When that happens our
beaches erode and permanently lose sand.
Blow winds and crack your cheeks.
Rage ! Blow !
You cataracts and hurricanes spout.
Till you have drenched our steeples,
drowned our cocks. Shakespeare
The weather plays an important part in the process of beach
building and beach erosion. During the past two centuries the
climate in southern California has been mostly stable and the
winters have been mild. But that is not always so.
In 1837 Richard Henry Dana sailed in our area. In his novel, "Two
Years Before the Mast" he wrote about the fierce storms called
"so'easters." Sailors were afraid to go to sea when the wind blew
from the southeast. Huge waves came up accompanied by torrential
rains and strong winds. When Dana came back to Los Angeles twenty
years later he noted that the "so'easters" did not blow anymore.
What happened to the storms?
Meterologists have studied the weather of the past and have learned
that southeast winds do blow up from time to time and cause big
storms. We now call those storms "El Ninos." The scientific name
is El Nino Southern Oscillation or ENDS for short. ENDS storms
have occurred in 1884-89, 1899-03, 1911-15, 1939-42. The greatest
river flooding in 200 years occurred in 1861-62. The weatherman
predicts that over the next 50 years we are likely to experience
four ENDS conditions. I wonder what those storms will do to our
beaches?
12
During the storms of 1970, the beach sand was rapidly removed by storm
surge, and the cobbles were withdrawn by the waves and thrown like artillery
against houses at Oceanside (Kuhn and Shepard 1980). The cobbles became a
destructive element again in the winter of 1980, contributing to the undermin-
ing and collapse of the beach road (figs. 24a, 245) and to the damage to
apartments and homes along the shore (figs. 25a, 25b). In south Oceanside,
roofs collapsed and windows were broken as the cobbles again became pro-
jectiles (fig. 26), although the waves were consistently less than six feet in
height. Even where riprap protected the shore, the cobbles moved as far as
twenty feet up the beach (fig. 27a). The stones were seen to move along the
shore and by June 1978 had largely disappeared (fig. 27b).
The Army Corps of Engineers (Hales 1978:27-32) suggested several
alternatives for stabilizing the sand and creating a buffering beach at Ocean
side. These included rock revetments, concrete seawalls, groin systems, sand-
fills, breakwaters, and a permanent sand bypass system. At the present time
sand-fills are the only method being attempted.
Figure 24a.
September 1979 view looking north along The Strand at
Oceanside. The structure and road were located on the
former beach. Riprap was placed to protect the concrete
seawall and road. Photo: G. Kuhn.
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Figure 24*.
February 1980 view looking at the same site as that in 24a.
The road and seawall were undermined and collapsed
between 12 and 15 February 1980; the waves were less than
six feet high. Photo: G. Kuhn.
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13
Big storms do two things when they hit. The wind kicks up massive
waves which are angry and powerful. When they explode on the beach
they tear and rip anything in their path. They cut huge chunks
out of the land and feed it to the ocean. At the same time the
downpour of rain on the land erodes away the sea cliffs. High up
in the mountains and along the coastal plain the rain washes away
loose dirt and rocks and sends them in a raging flood to the
beaches. There the waves chew up the sediments, spread them along
the beach and take most of the material out to sea.
It is an awesome sight to watch the war between the ocean and the
land in a major storm.
Usually the waves are kind and gentle and fun to play in. But
great damage can be done when the wind and the rains come. Other
disasters like earthquakes and volcanos and tidal waves can
drastically change the beach in one mighty upheaval.
URBAN DEVELOPMENT
There isn't much man can do about rising sea levels or storms. We
have to learn to live with the forces of nature and learn to
understand them. We need to pay more attention to how our urban
developments affect the beach. As we build our cities inland from
the beaches we have found out that we sometimes damage the beach or
cause problems without realizing it. For example look what we do
to the natural rivers. We build dams and reservoirs which block
the flow of sediment down to the beach. We mine the river sand and
use it to make concrete. We build concrete drainage channels to
stop erosion. We reroute rivers and change the way nature works.
So the supply of sand that used to feed our beaches has been
stopped and the beaches are starving.
We build houses and roads along the seashore and on top of the sea
bluffs. To protect these developments we harden the beaches with
rock and concrete in order to stop the waves from damaging our
houses. We have learned that building seawalls, and groins, and
jetties and revetments along the beach often makes the problem
even worse. All of these protections may have a good purpose in
the short run but in the long run the ocean will have its way.
There are many examples of where man has built a house on a sea
bluff and found out later that the waves have undercut the cliff
and caused the house to fall into the ocean. We need to study the
effects of building along the beach and be more careful how we do
it.
14
COBBLE BEACHES
In southern California beach cobbles are derived from two sources: from rivers
as the result of floods, and from sea cliff erosion (Emery 1955). The longest
cobble beach in southern California is found in south Carlsbad (Emery
1960:184) (fig. 23a). During the storms of January 1983, the beach cliff eroded
six to ten feet in places (fig. 23b). In 1960, Emery noted that the cobbles of this
beach, which is presently owned by the State of California, were the result of
local cliff erosion. Today, however, the cobbles are much larger and were most
likely dredged from the Oceanside small-boat harbor to the north, as early as
1963.
O
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CO
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Figure 23a.
April 1981 view from the Palomar Airport Road looking
south along the beach. Photo: G. Kuhn.
Sea Cliffs, Beaches and Coastal Valleys
of San Diego County, Gerald Kuhn.
FWs^hw^l SS^ssasw^- ij
Figure 23fe.
February 1983 view from the same vantage point as that in
23a. Note the extensive cliff erosion. Photo: G. Kuhn.
One of the most interesting projects along the San Diego coast is
the Oceanside Harbor. The harbor was started in 1942 to provide a
boat basin for the marines at Camp Pendelton. The harbor was
expanded and changed several times in recent years. The Harbor
was a financial success and has provided a popular boating and
recreational facility but it has caused a significant problem along
the coastline south of the Harbor. North of the Harbor sand has
been building up on the beach. Those beaches are among the finest
in Southern California. But south of the Harbor the once wide and
sandy beaches have been eroding. In the southern part of
Oceanside, beach residents have imported huge rock boulders to
protect their houses. The sandy beach is gone. Further south in
Carlsbad you will find the longest cobble beach in Southern
California. Many of the cobbles in Carlsbad came from the
Oceanside Harbor project. The Corps of Engineers study shows that
the beaches north of the Oceanside Harbor jetty are adding
(accreting) sand at a rate of two feet per year. The beaches south
of the Harbor are losing sand at a rate of one foot a year on the
average.
Oceanside and the Corps of Engineers are trying to deal with this
problem. When they dredge the Harbor they spread the sand on the
beaches to the south. They have also put in a sand bypass system
which is supposed to pump sand from north of the jetty to the south
beaches. So far it hasn't worked too well. This experience shows
that we have much to learn about how to manage our beaches.
SO WHAT CAN WE DO?
The Coast of California Study concludes that our beaches in San
Diego County will continue to erode in the future. The places
which will have the worst erosion are between Oceanside and La
Jolla and in Imperial Beach. The study recommends that we carry
out beach nourishment projects to feed sand to the beaches in order
to make up for the erosion we are experiencing. We really need
more studies to learn how, where and when to place sand on the
beach. It is not enough just to cover the cobbles with sand. We
need to find out how to keep the sand and not have it wash away in
the next big wave.
So we also need to build structures on the beach and offshore to
try to hold the sand in place and to capture and save more sand
from the waves. We need to experiment with sea walls, revetments,
berms, breakwaters, jetties and groins to learn how to build these
projects so that they will protect and enhance the beach. That
won't be easy. It will take a long time to gain the necessary
experience and it will take a lot of money. We already know that
the war between the ocean and the land is expensive and is a long
term process.
16
If the formerly predominant southern transport of sand is not restored, it is
difficult to estimate what will happen to the large quantities of sediment found
off portions of the inner shelf south of the San Diegulto River (Fischer et al.
1981). At any rate, the beaches from Leucadia south to La Jolla grew during
February 1982. An explanation is elusive at this point, but it may have some-
thing to do with the change of the longshore current direction. Erosion of the
beaches and cliff retreat accelerated during the stormy months in early 1983. At
Carlsbad Beach, where concrete restroom facilities and lifeguard towers were
built directly on the beach prior to the 1978 storms (fig. 30a), in 1983 two
concrete restrooms were undermined and bombarded by cobbles and small
riprap, and eventually collapsed and subsequently were removed. The adjacent
cliff retreated by as much as fifteen to twenty feet during one storm (fig. 30b).
The coast highway near the Carlsbad Encino Power Plant was severely
damaged and collapsed in places during this storm. Most of this very rapid
erosion occurred during the storms of late January and early February 1983,
which coincided with the perigean spring tide, a ten- to twelve-foot swell
coupled with extremely strong winds.
BEST ORIGINAL
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Figure 30a.
January 1978 view looking north along Carlsbad beach.
Photo: G. Kuhn.
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Figure 30i. *"
February 1983 view at the same site as that in 30a. The
lifeguard tower is gone, the restroom and the stairway have
buckled and collapsed, and the cliff has retreated fifteen to
twenty feet. Photo: G. Kuhn.
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17
Many beach protection projects have been built in the past with
mixed results. A sea wall was built in San Diego to protect the
Sunset Cliffs. Carlsbad and the State of California built a
seawall in 1985 to protect homes and public improvements along
Carlsbad Blvd. Mission Bay was a major dredging project which
turned a wetland swamp into a prime public recreation area.
Oceanside Harbor has provided boating and recreation and may
ultimately prove the feasibility of bypassing the sand flows to
feed southern beaches. The San Diego Gas and Electric Company
regularly dredges the Agua Hedionda Lagoon to nourish Carlsbad
beaches. The Batiquitos Lagoon Enhancement project proposes to
dredge over 3 million cubic yards of sand to restore beaches in
Carlsbad and Encinitas.
Ten years ago the cities of Del Mar and Carlsbad experimented with
the Longard Tube. It was a long sausage shaped sleeve of sand laid
along the beach to capture and hold the wave sand. It worked for
awhile but eventually was ruptured and bled its sand back to the
ocean.
Scientists now think one of the most promising ideas is to pump
sand out of the deep, offshore canyons and put it back on the
beaches where it came from. There are tons, and tons of sand not
far offshore in a long term bank account.
Nobody knows for sure what will work. The ocean is so powerful and
changeable that most of the works of man are soon swept away. We
know one thing for sure. The waves will continue to break upon our
shores. And the rains and winds will come when they will come.
And everything will eventually change. We know each seacoast is
different. What works in one place may not work in another.
But we always hope that man will have dominion over the earth and
that we will find out how to tame the ocean beast or at least we
will learn to live with nature in harmony.
"The inner peace that comes with the quiet
contemplation of a beach on a still calm
morning, or the feeling of exhilaration that
comes from riding a great wave in a small boat,
is more reward than most men ever know.
Fortunately the beaches of the world are cleaned
every night and every wave is a masterpiece of
originality. It will ever be so. Go and see."
Willard Bascom
Beyond all things is the ocean. Seneca
18
NEARSHORE(littoral) ZONE
UPLAND
BLUFF'or "'.''•'.'• '\
ESCARPMENT
BEACH SCARP.
(extends through breaker zone)
HIGH WATER LEVEL
LOW WATER LEVEL
CREST OF BERM
PLUNGE POINT-
BOTTOM-
Figure 6 An Idealized Beach Profile
[U.S. Army Corps of Engineers (1977a)
How Development Initiates Lanslides
Cliff Fails, Waves
Eventually Cut a
New Cliff Line
Cliff Slides
.*•'.. Along Slip ZoneWater Weakens
Soils
and Creates a
Slip Zone at
Clay Boundary
Overwatering
Saturates
Permeable
Cliff Strata
How Development Increases Erosion
The Gully
Washes
and the
AGullyStarts to
Form
Development
Concentrates
Runoff ' '• "., /'/''','/'•'
Natural
Runoff "•
Spreads Out '
Along Cliff ",
I low development can initiate landslide activity und cliff erosion
h v chiin^inv, gronndwuH'r conditions and concentrating surface riino/J.
US AAmt Co^p4 oi Engine.zx.4 Annual RepoA^t 1986-8?
19
A LAYMAN'S TQ BEACH
GUIDE EROSION
For more information on Beach Erosion read:
BASCOM, WILLARD, WAVES AND BEACHES
A fine general text for the beginner.
CARSON, RACHAEL, THE SEA AROUND US
A classic and well written book about the ocean and its
relation to man. 1951
U.S. ARMY CORPS OF ENGINEERS, 300 N. Los Angeles Street, LA 90012,
(213) 688 5320
"CCSTWS STUDY. FINAL REPORT 1991"
Tells all about the seven year study of the San Diego Coast.
Very technical.
"LOW COST SHORE PROTECTION" 1981
A property owners guide . Good basic description of waves and
causes of erosion on beaches.
KUHN, GERALD, SEA CLIFFS. BEACHES AND COASTAL VALLEYS OF SAN DIEGO
COUNTY. 1984. University of California Press
Some amazing stories and horrifying implications of storm
damage. Good photos and current examples of beach erosion.
INMAN, DOUGLAS, Scripps Institution of Oceanography 1980
"Man's Impact on the California Coastal Zone"
Good diagrams and descriptions of coastal processes and how
structures such as groins work.
GRIGGS, GARY
"The Case For/Against Coastal Protection" 1982
Ocean Studies Symposium, California Coastal Commission
245 W. Broadway, Long Beach, CA
SANDAG (San Diego Association of Governments), 401 B St, San
Diego, CA 92101, 619-595-5300
"SHORELINE PRESERVATION STRATEGY FOR THE SAN DIEGO REGION"
JULY 1992
"SEACLIFFS, SETBACKS AND SEAWALLS." Feb 1992.
LA COUNTY
DEPT OF BEACHES AND HARBORS
LOST AND FOUND
An outstanding video explaining beach erosion and renourismment
projects in Los Angeles County. Non technical, educational.
A picture better than a thousand words.
13837 Fiji Way, Marina Del Rey, CA 90292
Greg Woodell (310) 305 9537
20
FRANK ALESHIRE CARLSBAD February 1994