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CITPF CARLSBAD - AGENDWILL
AB# h% 17 TITLE: DEP
CITY MTG. 5/6/86 BEACH EROSION COMMITTEE REPORT
DEPT. CM CITY
RECOMMENDED ACTION:
City Council to receive Final Report from the Beach E
Committee.
ITEM EXPLANATION
On August 27, 1985 the City Council appointed the Beach E
Committee, consisting of seven members to study beach erosi
the problems of the Carlsbad coast line. At that time, th
Council charged the committee with delivering a report b
you on/or about six months later. The following scope o
was outlined:
1. To review prior studies, articles, and materials.
2. To obtain current input from available sources.
3. To enumerate, evaluate, and study the beach erosion pr
specific to Carlsbad's coast line.
4. To relate and coordinate the lagoon and coastal p
area.
5. To develop plausible solutions to mitigate the beach e
problems and identify possible sources of funding.
6. To report these findings to the City Council.
The letter of transmittal and report with attachments attac
this agenda bill is the result of the Beach Erosion Commi
efforts over the past half-year and is presented forthwi
your evaluation.
EXHIBITS
1. Letter of transmittal from Mario Monroy, Committee Cha.
dated March 28, 1986.
2. Carlsbad Beach Erosion Report
EXHIBIT 1
r 1) e t
March 28, 1986
TO: CITY COUNCIL
FROM: Mario Monroy, Chairman
Beach Erosion Commmittee
CARLSBAD BEACH EROSION COMMITTEE REPORT
Attached is the Beach Erosion committee Report which yo
authorized on August 27, 1985. The recommendations of th
report are summarized as follows:
1. The City of Carlsbad should continue to support the BEAC
Joint Powers Committee.
2. The City of Carlsbad should hire a consultant to conduct
yearly series of beach profile surveys.
3. The City of Carlsbad should establish a permanent Beac
Erosion Committee.
4. Through BEACh, the City Council should become direct1
involved in conducting necessary public information an
education on beach erosion and its solutions.
5. The City Council should work through BEACh in tt-
continued development of "sand rights".
6. The City Council, through BEACh, should lobby that befor
building permits are granted for dams in California river
they be required to include plans for sand bypass ar
transport to the beaches as part of the architecturE
design.
7. The City Council, through BEACh, should sponsor region2
conferences on coastal erosion.
8. The City Council should continue to protect the bluff
from erosion.
9. The City Council should finance coring of the AgL
Hedionda Lagoon to determine sand content for future beac
nourishment.
10. The City Council should adopt a policy that insures th2
any beach quality material dredged from City lagoor
should be placed on beaches within the City only.
J t c e
City Council
Carlsbad Beach Erosion Committee Report
March 28, 1986 Page: 2
'81. The City Council should lobby through our electet
officials in Sacramento for recognition by the State Park:
and Recreation Department of added recreational value oi
Southern California beaches because of the warmer air anc
water.
12. The City Council should pursue the formation of BEACh eve!
if all of the originally proposed members do noi
participate. The principles of BEACh are essential to thi
solutions to beach erosion.
MRM:lch
1 I EXHID1 0 e
CARLSBAD BEACH EROSION REPORT
March 18, 1986
As requested by the Carlsbad City Council on August 27, 1985
Beach Erosion Committee has reviewed previous studies
articles. The committee was very fortunate in getting exp
input from those listed below on their respective subjects:
Ron Flick Oceanographer for the California Department
Boating and Waterways assigned to Scri
Institute of Oceanography - "Sea Level and
Effects on Beaches and Erosion."
Bill Fait State Department of Parks and Recreat
-Policies.
Dan Muslin Army Corps of Engineers - Projects the Cc
has worked on in Southern California.
Douglas Inman Director, Center for Coastal Studies, Scri
Institute of Oceanography - "History of C2
fornia Beaches."
W. G. Dyson SDG&E - Dredging Aqua Hedionda Lagoon
E. Aguardo Professor of Geography, San Diego St
University - Weather.
SUMMARY OF CURRENT INFORMATION
Beach erosion in the Oceanside Littoral Cell, which exte d
Dana Point to La Jolla (see Figure I), is well documented.
On a local basis the Federal. Government has assumed respor
bility for funding mitigation of beach erosion at Oceans:
This erosion was caused by the construction of the Del Mar I
Basin on Camp Pendleton in '1942 (see Figure 2). The Del
jetties have interfered with the gross longshore transport
about 810,000 cubic yards OF sand per year to the south\
during the winters and 550,,000 to the northwest during
summer. While the general dynamics of sand movements
somewhat understood, detailed studies of the Carlsbad beac
have not been made. Even minor changes in the weather, tides
wave patterns can have significant effects on sand flow, mal
it almost impossible to determine what is happening in spec
areas.
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This interference with the natural course of sand flow has b
in addition to the construction of numerous flood control bas
and the persistent sand mining in the upstream beds of the
Luis Rey and Santa Margarita Rivers which greatly diminish
natural source of sand for the beach. The sand flow to
beaches from the San Luis Rey River has been diminished si
1922 by the construction of Lake Hensh8w dam and in the Sa
Margarita River since 1949 by 'Vail Lake.
In the period between 1957 and 1961 the Federal Governm
further aggravated beach erosion to the south of the Del Mar B
Basin by the extension of the jetties and the construction of
jetties and groins for Oceanside Harbor. This construction
only created a larger sand trap but it also diverted the s
further offshore, These harbor jetties have interfered with
net southerly migration of abalut 260,000 cubic yards of sand
year in the Oceanside Littoral Cell. The Federal Government
not assumed responsibility f13r the effects of longshore s
transport south of Oceanside.
Over the past 25 years between 1957 and 1982, about 11 mill
cubic yards of material has been dredged from Oceanside Har
and placed on Oceanside beaches. However, this sand nourishm
program was not as effective as it could have been because
breakwater had a double effect. First it was trapping more s
north of the harbor and secondly the longshore transport co
pick up sand in the newly nourished beaches south of
breakwater. This, to the bei7efit of Carlsbad's beaches, ac
to further accelerate a transfer of the dredged sand to
south. All this, plus the fact that prior to 1978 there
minimal beach erosion because of relatively mild weather,
protected Carlsbad's beaches until then.
Carlsbad's beaches have begun to disappear more seriously dur
their cycles, with the sand completely eroded during the storms
1983. In subsequent summers, sand deposition on Carlsbad beac
has been minimal.
Prior to 1978 - 1979 Carlsbad had beaches, at least in the no
end of the city, as wide 'as seventy or eighty feet.
thickness of the sand beach was seven feet at the foot of
bluff. Now there is no sand at high tide and a maximum thickn
of sand of only three feet during the summer. (See Appendix A)
The fact that Oceanside hasn't done any sand nourishment si
1982 may prolong the recovery period for the Carlsbad beach
Consequently, until Oceanside resumes a sand replenishm
program the damage to Carlsbad beaches and bluffs by mild sto
could be severe. At the present time, due to the lack of be
profile data, it is not known whether the sand is offshore as
the past to nourish the beaches naturally in the summer.
there is no sand offshore, which is likely because of a long t
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deficiency in the supply of sand, Carlsbad's beaches will !
progressively narrower and narrower.
The City of Carlsbad is fortunate to have three lagoons (5
Appendix B), two of which could be used as a source for s:
replenishment of the Carlsbad beaches. They are all silting
and will need to be dredged. Currently plans are being develoF
for dredging the Batiquitos Lagoon which could provide as much 2.5 million cubic yards of sand. This is enough to lay a blanE
of sand 5.3 miles long, six feet deep and 400-feet wide. Tt
volume of sand may not be available for another thirty yea However, to effectively utilize this volume of sand, be(
profile data is needed to determine where to place it so as
best retain it (see Appendix C). Presently the feeling of
Scripps people who spoke to us, is that the beaches becc
progressively steeper to the south. If this is the case, 1
southern beaches are unlikely to retain sand for any length
time.
Another source of sand, of course, is the Aqua Hedionda Lagoi
This consists of outer, inner and middle lagoons. The in1
lagoon is east of 1-5 and the middle lagoon is between 1-5 t
the railroad trestle. The outer lagoon which is dredi
periodically by SDG&E has furnished an average of 116,000 CUI
yards of sand per year since 1955. It is estimated that
entire lagoon could provide at least 128,000 cubic yards of s per year for beach nourishment. (This is about half of the
southward longshore transport of 260,000 cubic yards.)
The beaches of Carlsbad will also be replenished by the Oceans
Sand Bypass, if effective. This bypass is an experimental sys
in its development stages which will be monitored for five ye
by the Corps of Engineers. Therefore, this source of repleni
ment may take some time to affect Carlsbad beaches. The syst
if successful, will have the capacity to move 400,000 cubic ya of sand per year. However, the sand replenishment could
delayed if Oceanside beaches have become too steep to retain
sand. This sand bypass is supposed to be operational in
spring of 1986 at a cost to the Federal Government of $
million.
If the Oceanside sand bypass is not effective it may be necess
to build structures to retain sand and protect property, blL
and highyays. Studies for Oceanside by the U. S. Army Corps
Engineejjs and by consultants Douglas L. Inman and Scott 1
Jenkins have considered various types of structures. SE
Table I. The review of these studies shows that, besides
sand bypass, serious consideration for protection of the beac
has been given only to groins and offshore breakwaters.
Inman-Jenkins study suggested a series of groins, some temporz
while the Corps of Engineers favored an offshore breakwat
Based upon the similarities between Oceanside and Carlsbac
combination of these types of structures could be a possibil
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for the protection of Carlsbad's beaches if sand nourishm
cannot be provided. In order to retain replenished sand,
possibility of installing such sand traps before be
replenishment should be considered.
Prof. Douglas L. Inman in his presentation and writings
indicated that sand is a natural resource just as water is.
points out that dams benefit populations and agriculture and h
coastal communities and beaches. Therefore "the cost
nourishing beaches with the sand intercepted by 5the dams sho
be a legitimate part of the cost of using water."
There gppears to be nothing in the State Parks and Recreat
policy that will prevent them from conducting beach restorat
projects. This agency recognizes the scenic value of
California beaches. However, their funding priority to rest
and protect the beaches does not reflect the fact that San Di
state beaches also provide an extremely important recreat
facility because of the warm air and waters in this area. T policy has the highest impact on the youth and lower inc
population.
CONCLUSIONS
1. Sand on the beaches is the best protection against be
erosion and property damage.
2. Protecting beaches and property solely by sand nourishment
an expensive way to accomplish this because replenishrr
must be renewed again and again to be effective.
3. Douglas C. Inman stated that there are only about fift
years of sand supply on the beaches north of the Oceans
Harbor for the sand bypass.
7 4. Review of the Corps of Engineers studies and manuals
shore protection show that offshore breakwaters can be
most cost effective way of protecting beaches from \
action under the right conditions. However, offst
breakwaters by their nature will severely affect the si
interfere with boating and diving, and can be politic2
unpopular, as Oceanside found out.
5. Although groins are effective in retaining sand 1
longshore littoral transport 9 they are not effective aga:
sand losses from onshore-offshore sand movements. They
create dangerous riptides but seem to improve surfing.
are esthetically unattractive to the public and unsafe
children.
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6. The regional flood control system within the Oceanside L
toral Cell is blocking the natural transport of sand to
ocean. Sand mining of the rivers is further aggravating
short age.
7. Because beach erosion is a regional problem, only a regio
political organization can stand up to the environment
legal and political challenges which can be made to effo
to protect the beaches.
8. Because beach restoration or protection requires very la
capital expenditures in addition to regular maintena
expense, the most effective way of lobbying for funds f
the various state and federal agencies (see Table 11) wo
be through a regional organization such as BEACh which
political clout.
9. In discussions with the State Parks and Recreation Depa
ment, it becomes evident that funding to mitigate be
erosion is a low priority within this agency.
RECOMMENDATIONS
1. The City of Carlsbad should continue to support the BE
Joint Powers Agreement and SANDAG's subcommittee on be
erosion. Without the political clout of a regional approa
it is impossible to compete for a share of funding froi
fixed budget, whether state or federal.
2. The City of Carlsbad should hire a consultant to conduc
yearly series of beach profiles surveys (see Table I
because:
a. Without data it is impossible to convince the public
agencies that there is a problem.
b. Funding such a survey would demonstrate to other agenc
and to the public that the city recognizes the econo
impact of erosion.
c. The profile data would help the city to determine wh
best to place sand nourishment from the lagoons
determine the effectiveness of any nourishment project
d. These survey results would be a source of valuable d
for BEACh.
3. The City Council should establish a permanent Beach Eros
Committee consisting of no more than three citizens and
city staff, one from Engineering, and one from Buildinc
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Planning. This committee should also serve as an advisor
the City Council's representative on BEACh.
4. Through BEACh, the City Council should become direct
involved in conducting necessary public information i
education on beach erosion and its solutions.
5. The City Council should work through BEACh in the contint
development of 'Isand rights" under the Public Trust Law i
restrict sand mining in coastal flood plains except for be;
nourishment.
6. The City Council through BEACh should lobby for a change
building codes for dams in California rivers to require pli
for sand bypass and transport to the beaches as a condit.
for issuance of a building permit.
7. The City Council through BEACh should sponsor regio
conferences on coastal erosion such as the one held in
Diego on February 6-8, 1985.
8. The City of Carlsbad should continue to protect the blu
from erosion by diverting storm drains away from both pub
and private beaches per its Master Storm Drain Plan.
9. The City Council should finance coring of the Aqua Hedio
inner and middle lagoons to determine their sand content
future beach nourishment.
IO. The City Council should adopt a policy that ensures that
beach quality material dredged from City lagoons should
placed on beaches within the City.
11. The City Council should lobby through our elected offici
in Sacramento for recognition by the State Parks and Recr
tion Department that the warmer air and water of San Di
Coastal State beaches gives them an added recreational va
not available in the north. At the present time there is
funding for the restoration of southern public beach
Under their present funding priorities the Parks and Recr
tion Department is not carrying out its responsibilities the fullest. BEACh and SANDAG should support the City
Carlsbad on this point.
12. The beach communities under the supervision of their resp
tive county and city governments and with guidance f
appropriate state and local agencies from a joint commit
empowered to:
A. Superficially investigate the beach erosion problems
the Oceanside littoral cell.
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€3. Engage the services of coastal process expe
(scientific, engi neering, legal and administrative)
that they may closely examine the problems and possil
solutions for the Oceanside lottoral cell.
<T, &
DAVID CASTEL
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TABLE I1
FINANCING EROSION CONTROL
I. STATE FUNDS
A. State Lands Commission
8. Department of Boating and Waterways
C. Department of Parks and Recreation
D. State Coastal Conservancy
E. Department of Fish and Game
11. FEDERAL FUNDS
A. United States Corps of Engineers
B. 99th Congress, 1st Session (Calendar No. 152) S 959
(Report No. 99-71) to amend the Coastal Zone Managem
Act of 1972 to provide authorization ou appropriatio
and for other purposes. Distribution of federal fun
coming to the state from offshore drilling.
C. U. S. Fish and Wildlife Service.
D. Direct Congressional funding.
111. REGIONAL FINANCING ALTERNATIVES
A. Assessments
B. Fees
C. Taxes
D. Bonds
IV. CARLSBAD: Transient occupancy tax
V. UTILITY COMPANY - SAN DIEGO GAS & ELECTRIC
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TABLE 1x1
BEACH SAND LEVEL MEASUREMENTS
Carlsbad, California
1. Six range lines (profiles) surveys
2. Data collection
a. Land Surveyors - every two months - to maximum wad
depths at low tide.
b. Offshore surveys on three of the land surveys to 40 f
depth every two months.
3. Estimated cost: $25,000 per year
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REFERENCES
1. Sea Cliffs, Beaches, and Coastal Valleys of San Diego Coun
by Gerald G. Kuhn and Francis P. Shepard, 1984.
2. Progress Report on Beach Erosion Control Study, San Di
County, California in Vicinity of Oceanside by Los Ange
District U. S. Army Corps of Engineers, January 1977.
3. Oceanographic Report for Oceanside Beach Faciliti
Prepared for the City of Oceanside by Douglas L. Inman
Scott A. Jenkins, 1983.
4. Putting the Beach Back at the Oceanside. A Case Study
Locally Initiated Beach Restoration, by Larry M. Bagley
Dana H. Whitson. Journal of the American Shore and BE
Preservation Association. Vol. 50, No. 4, October 1982.
5. Budget of Sediment in Southern California: River Disch:
versus Cliff Erosion by Douglas L. Inman. Californj
Battered Coast. Proceedings from A Conference on Coaz
Erosion, San Diego, February 6-8, 1985, pg. IO.
6. Beach Erosion - A Planning Perspective and Appendix Secret
for Resources Policy for Shoreline Erosion Protection. St
Parks and Recreation Department.
7. Shore Protection Manuals, Volumes I and 11, U. S. Army Cc
of Engineers, 1984.
8. Oceanographic Report for Community Facility District Beach Facilities for the City of Oceanside, Douglas
Inman, July 21, 1983.
8 e 0
EVALUATION AND ENUMERATION OF CARLSBAD BEACH EROSION
by Sally Vigil
INTRODUCTION
This in an outline description of beaches and cliffs designa
as Areas A, B, C, D and E on enclosed map. Also, note cha
citing deepwater direction and shore erosion from Santa Margar
River to Agua Hedionda Lagoon. Finally, only each area's uni feres pertinent t o erosion are described along with corn
characteristics.
Common Characteristics
Beach areas A, B, half of C, D and half or most of E lie at ba
of cliffs, popularly called The Bluffs. It all represents
Santiago formation with terrace deposits on top. They cont
hard, gray clayey material and much silt sandstone. terr
deposits are sand and cobbles. Silica sand and some mica nour
beaches from lagoons and few remaining bluffs not yet fortif
by cement or rock.
I. Area A is privately owned to mean high t'de mark - a va
legal setting unchanged since 1967. h) Four pub
accesses within six city blocks are city-owned
maintained by Parks and Recreation, under jurisdiction
Carlsbad Police. Three accesss in addition are owned
maintained by California Coastal Conservancy or priv
property associations. All are heavily trafficked
tourists, residents of Carlsbad (both townspeople and th
living in beach structures as renters or owners)
representing general public. All beach areas suffe
similar erosion problems plus cobbles, but Area A recove
faster in 1983 for these reasons:
A. Oceanside sand dredging replenishes Area A sooner.
6. South to north littoral drift works well since 19
although there is some dispute as to whet??? or
this has become variable since 1980. T
controversy needs study.
C. Mild winter storm activity from 1983 until Novemb
1985.
APPENDIX
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1. Scripps predicts bad year as being 1987 and or two others into year 2000.
D. Experimental Longard Tube, financed by property own
to retain and build up sand, and rebuff waves in A
A, is now gone after two mild winters and two
storms.
1. Northern section had one huge tube, of infer
material, which was torn apart anyway very ea
after only one season of mild wave action.
a. Cobbles penetrated; it literally bur
after being observed tearing like rot
cloth.
2. Tubes at southern area are double, small, pic
back types which are successful in Australia.
3. It is a noticable buffer but does not withst
storms. Replacement necessary.
a. Lost insurance after first damage.
b. February 6, 1986 storm took all the rest.
E. Since Areas 5, D and E are usually cobbled, Area A
more users of beaches.
1. No lifeguards, no consistent maintenance
supervisory authority other than police dui
summer.
11. Years from 1963 to 1986 have seen heavy level
construction of buildings, seawalls, rock revetment
accessways. This has revealed to engineers a ro:
coaster type topography made up of hard-pan - a crust
hard material not quite bedrock. This may exp:
variations in beach stability regarding construction
erosion on all areas. The following conclusions were di
in 1980 when massive building occurred:
A. Sand is still the number one protection against w
and erosion threatening bluffs and property.
5. At least erosion due to small animal burrowing
solved by building.
C. Individual storm drains should be at street level.
APPENDIX
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D. Cobbles hold sand but endanger property too.
E. Most suprising to engineers is the fact that oti
areas may not be at all like Area A nor like ei
pfver. (Not all have been surveyed geologicall'
1. Some bluff areas seem to be edrock but cruml ( 49 when wet as in rain erosion.
2. Areas D, C and E are mostly sandstone with si
mica.
111. Storms of 1983 coincided with rare high wave action I
occurring since, thus sand renewal. However, the six f
drop in sand level is not really changed since late 1970
Storms of February, 1986 have not changed this view as
February 18, 1986.
A. Encouraging footnote is as follows: "Fut
astronomica component of extreme tides still wo
exceed those of 1982-83 by more than 0.06 -0.09M.
This can give room for hope plus incentive to reth
as to remedies. Since in fifteen years there will
no more 290,000 cubic yards per year drifting f
Oceanside to be lost in La Jolla Canyon and Carls
Canyon, entrapment and recycling of dredged sand
Aqua Hedionda must be a long term option and in s
agreement with SDG&E.
IV. The top end of Area A is Buena Vista Laqoon.
A. No beach sand, just silt and fine sediment.
6. Water at weir is released once a year causing eros
at north end of Carlsbad beach called The Point.
1. The sand return by summer has been the best
all beaches.
2. November and February storms of 1986 cat
breakdown of weir as water poured over j
ocean. (See news picture.) Released sand shc
be observed and monitored.
C. St. Malo development (north of lagoon and across 1
to Oceanside) has properly designed rock revetn
according to Dr. Doug Inman.
APPENDIX
2 0 m
-
1. Protects propety without (gyusing scouring
sand, thus negligible loss.
D. Inman suggestion: Original Scripps study of E
drift can continue or be reinstated while sand stor
is pondered, especially that from Batiquitos Lagoor
1. The Point at Buena Vista outlet to the sea is
good spot since sand placed further north tE
longer to drift south and should be retained
recycled on a short term plan as suggestec
opening pages dealing with short term and 1
term solutions as to erosion.
2. The Committee considers it a plus that sand nc
of Power Company jetties gets trapped in 1
Hedionda. Better use should be made of ii
recycling at dredging period. As example
should be stored in berm on and against bluffs
(11) 3. Refer to Carpenteria Solution again.
a. Berms can be destroyed in one storm,
consultation necessary.
AREA B
I. Carlsbad State Beach, a state owned public beach i
called Tamarack, maintained by Parks and Recreation witk
structures left on beach since 1980-83 storms. State pl
no remedial improvements even though replenishment of E
was fairly good summers 1983-84. In those summers, be
was comparatively unused because of poor access and park
limitations.
A. Beach B terminates at jetty at Aqua Hedionda and PC
plant.
1. Lagoon used by power plant as cooling out1
also is popular small boat and fishing area.
8. Sandy beach due to proximity to jetty at time
dredging lies south of second jetty.
C. Third jetty is at sewage disposal just before Carl$
Submarine Canyon.
APPENDIX
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1. No jetty is extended enough to trap sand.
2. CanyB’f, controversial as to whether enlarging
0. Committee agreed that cost of dredging could be s
not.
as cost of jetty extensions.
1. January dredging does not help sand retent
because of sf,rns. Dredging no help with
south jetties.
2. Dredging could be done more often at right ti
in cooperation with City and State.
11. Power Plant interest in sandy beaches is absent.
A. On record as saying they do not want sand placed nc
of jetties, or even north of Batiquitos Laqoon in c
south-north return of sand enters lagoon.
8. Officialf9ytate lack of desire for Oceanside by-F
to work.
AREA C AND HALF OF D
I. Flats to bluffs to flats again describe the beaches, ov
in part by private home owners at beach area cal
Terramar and Carlsbad State Beach also called Sc
Carlsbad and Ponto Beaches.
A. Sea cliffs with narrow, fragile beach, rnoc
sandstone.
1. Many cliff failures due to ground water.
blockfalls betweeen 1978-83.
2. At this writing all cobbles, no sand due
February 1986 storms. Some sand re.
expected.
11. Area D shares state beach land with Area C and terrnin
at sewage disposal.
A. More cobbles and eroding bluffs.
APPENDIX
* e
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B. Some narrow flat areas with water from Encinas Cr
behind beach and bringing gravely material to beach
C. February 1986 saw little rain erosion on bluff area
AREA E
I. South Carlsbad State Beach, the "Largest cobble beach
Southern California". It is at the base of high cli fading down to the longest Carlsbad flat land beach cal
Ponto thence to the mouth of Batiquitos Laqoon. St
Parks and Recreation operate an R.V. park at the top bluffs. Storm drains severely gully bluff face and cau
landslides in 1980 and 1983. Road closed in 1983
cobbles moved on shor(el.O) Flat beach subject to flood
from San Marcos Creek.
Finally, at this writing, all beaches are cobbles because
storms February 18, 1986.
APPENDIX
0 0
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BIBLIOGRAPHY
1. Flick, Ron, seminar with Beach Erosion Committee, Oct.
1985.
2. Griggs, Savoy, Livinq With The California Coast, D
University Press, Durham, NC, 1985, p. 351.
2b. Kuhn, Gerald, Sea Cliffs, Beaches , Coastal Valle
University Press, Los Angeles, CA, p. 63.
3. Moffatt & Nichols, Engineers, Long Beach, CA, Mr. Dunham
Property Owners Area A, July, 1983.
4. Willard, Syd, Parks and Recreation Dept., State Geologi
speech to Beach Erosion Conference, Santa Barbara,
October 3, 1985.
5. Flick, Ron, Journal Waterway, Port, Coastal and Ocean, Eng Div., Amer. SOC. Civil Eng., 1984, to Carlsbad Committ
Oct. 3, 1985.
6. Inman, Doug, Scripps Oceanography, seminar at Carls Committee meeting, Nov. 7, 1985.
7. Kuhn, Gerald, Sea Cliffs, Beaches, Coastal Valleys, San D;
County, University Press, 10s Angeles, CAY p. 63.
8. Ulman, Dan, Corps of Engineers, to Committee meeting P
1985.
9. Dyson, Bill, SDG&E to Erosion Committee, Dec, 12, 1985.
IO. Griggs, Savoy, Living With The California Coasti, [
University Press, Durham, NC, 1985, p. 351-53.
Invite member of California Lifesaving Association to show slides and lecture about procedures at Carpenteria before, during and after stor Stephen Lane, PO Box 445, Carpenteria, CA 93013. Telephone (805) 684
11.
APPEND1 X
e 0
Staff Photo By ROBERT FAABORG
WATER boils out of a rain-filled Buena Vista Lagoon Saturday,
spilling over the weir into the Paclfic.
COASTAL STORMI
AREAS - ?ENAT
STATlS - %Gi-
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FIGURE ES- I
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-
i f,
A. -:
..
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..
- ..
- - - - - - - - -
i ',
- -
- - ez e= m=
d= a= -= K= w= &E
OE w= m= -
b= __.
- - - -
- - - - - -= - - - - - - - - - - - 7 - - - - - - - - - - 7 - - - - - - - - - - - - - - - - - c_ - -
0- -
i. / -\ /,
z
4 v::.~;~*;~o.ra--' Q,Qclv) % .9 E .s g c cda,~v)aaaoox b5G Q, V.d rd v) 3s v) &a @%
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EARLSBAD LAGOONS
SOURCE OF BEACH SAND REPLENISHMENT
by John Gray
IMPACT ON BEACH EROSION
During most of the past 6,000 years, Carlsbad’s lagoons delive
sand to the beaches. During the past two hundred years, howevc
Western Civilization has been interfering with this deliver
This condition is not peculiar to Carlsbd, though.
throughout Southern California, beach materials are being trap1
by 311 water supply lakes and flood cijontrol reservoirs and
additional 77 sand and gravel quarries.
DESCRIPTION OF CARLSBAD’S LAGOONS.
Carlsbad’s three lagoons are, from north to South, Buena Vis
Aqua Hedionda, and Batiquitos. All three of them are bridged
U.S. Highway 101, the railroad track, and Interstate-5.
Buena Vista Lagoon lies between Carlsbad and Oceanside. The c
limits are a zigzag line which gives the southern half of
lagoon to Carlsbad. The entire lagoon is included in the
Maxton Brown Bird Sanctuary. The watershed of Buena Vista Lag
consists of about 19 square miles within the cities of Vis
Oceanside, and Carlsbad. Its principal source of water is Bu
Vista Creek, rising in Vista. The lagoon is fresh water, kept
by a fixed weir at the mouth of the lagoon. From the weir
Jefferson Street on th? east, it is about 1.4 miles long,
about 1/3 mile across, Buena Vista Lagoon includes about
acres controlled by the California Department of Fish
Game.
Aqua Hedionda Lagoon extends 1.7 miles inland and is about
mile wide. It comprises about 230 acres of open salt watgr-
about 200 acres of salt marsh, mud flats, and salt flats. ’ ”
is kept open to the sea by tidal action and periodic dredging
the outer lagoon by the San Diego Gas and Electric ComF
(SDG&E). Its principal source of fresh water is Aqua Hedic
Creek, which drains a watershed from Vista, San Marcos, Calab
Lake, and county lands to the south.
Batiquitos Lagoon extends about 2-1/2 miles inland from the oc
to Camino Real. It is about 1/2 mile wide. Its drainage bE
includes San Marcos Lake, San Marcos Creek, and Encinitas Cree
b
APPENDIX
e
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The lagoon is only opened to the sea by bulldozing the berm
its entrance when storm runoff threatens the sewage pump
station there. Much of the lagoon's 526 acres are dry salt fl;
most of the year.
PERTINENT HISTORY
Most of the following was extracted from the qummary of the BUI
Vista Lagoon watershed sediment control plan.
During the Pleistocene Epoch, Carlsbad's lagoons were ri
valleys, draining into the sea. At the end of the Ice Age s
6,000 years ago, the ocean rose and flooded saltwater into th
river valleys, The river bottoms were covered with terr
deposits--sand and gravel and silt which had come down from
watersheds. Such erosion continues up to this day.
During summer months, a berm might be built up blocking the ri
mouths, but during the rainy season, flood waters would br
through the berm, carrying sand and gravel to the beaches. Up
the advent of civilization the watersheds were protected
vegetation, and the erosion of the hills was minimized.
About 200 years ago, Western Civilization came to Californ
Herds of grazing animals reduced the vegetation on the hillsid
Then farmers cultivated the slopes and further denuded tt-
Then developers graded the slopes and highways were covered
mud slicks as rainstorms washed away the unprotected soil. E
stage of urbanization caused more erosion of the watersheds
deposited more sand, gravel, and silt in the lagoons wh
sedimentation could occur in the calm water. The lagoons si1
UP-
When the developers built homes and paved streets in
subdivisions the erosion process changed. There was not so n
sand and gravel to wash down into the lagoons, but the water
a higher velocity as it ran down the gutters. So it eroded
remaining stream beds. Their mud, silt, clay, sand, and grf
was carried into the lagoons where siltation continued to OCCL
Across the lagoons, roadbeds were built for the railroad,
Highway 101, and for Interstate-5. Buena Vista Lagoon
another barrier at its east end carrying Jefferson Street. Tt
obstructions restricted the flow into the ocean, and the qi
water allowed even more silt to settle out in the lagoons.
Buena Vista Lagoon had a weir installed across its mouth in I!
This kept the ocean out until 1969 when a flood washed out
weir. It was rebuilt in 1970 and Buena Vista Lagoon became
APPENDIX
i * m
-
freshwater lake, except for sewage which was dumped into
regularly until 1960 and spilked into it sporadically ever sin1
Buena Vista Lagoon silted up.
The San Diego Gas and Electric company bought Agua Hedio
Lagoon, and commenced dredging it in 1952. Most of the follow
information has been extracted from the U,qb Army Corps
Engineers "Appraisal Report for Agua Hedionda".
By 1954 the outer lagoon had been dredged to a depth of ten f
and a tidal prism flowed through it to provide clear ocean wa
to cool the condensers of the Encina Thermal Power Plant. T
dredging produced about 4,278,000 cubic yards of sand initial
1,024,000 yards from the outer lagoon and 3,254,000 cubic ya
from the middle and inner lagoons. This sand was dumped on
beach. An inlet and an outlet further south, both protected
short twin jetties, provide circulation for the tidal pri
Nevertheless, SDG&E has to q$edge the sand bar from the ou
lagoon about every two years.
Most of the follgwing was extracted from the Batiquitos Lag
Enhancement Plan. In recent years, Batiquitos Lagoon has b
mostly salt flats. It was open naturally most of the time un
the mid-'60's. Since then, it has been opened with a bulldo
occasionally to let the stagnant waters out and thus av
flooding the sewage booster plant on the south side. The bot
of Batiquitos Lagoon is covered with fluvial material, mostly
sand and gravel, topped with a thin layer of clay and si
Sedimentation of Batiquitos Lagoon increased rapidly as La Co
and the San Marcos valley were subdivided.
LAGOONS AS A POTENTIAL SOURCE Of BEACH SAND.
If Carlsbad's beaches are to be replenished to combat be
erosion, they should be nourished periodically. The lagoons
provide a handy and continuing source of sand, if they
dredged periodically.
Unfortunately, not all the sand in the lagoons is usable on
beach.If the sand is too light, the ocean will float it awa)
Silt or clay-sized materials won't stick on the beac
Generally, an upper layer of silt, composed of clayey shales
mudstones, will have to be disposed of before the sand useable
beaches can be dredged out. Most often such silt is used
landfills, such as in the area just east of Jefferson Street
the former Buena Vista Lagoon. Again unfortunately, such cla)
not a stable platform for heavy construction.
APPENDIX
a v
-
From Buena Vista Lagoon, it would be possible to dredge f
10,000 to 100,000 tons of sediment per year, but only 5L to
of that would be sand suitable for beach nourishment.
A weight test on Aqua Hedionda sand indicated a cubic yard wo
weigh 2,565 pounds, or 1.3 tons. The maximum annual sand prod
tion of Buena Vista Lagoon would be 20% x 100,000 tons + 1.
15,385 cubic yards of sand. The minimum annual sand product
would be 5% x 10,000 tons + 1.3 = 385 cubic yards.
Whether it produces only 385 cubic yards or 15,385 cubic yards
sand per year, something must be done perjodically to prevent
Buena Vista Lagoon from silting up again.
Aqua Hedionda Lagoon consists of outer, middle, and in
lagoons. No information is available on the contents of
middle lagoon, between 1-5 and the railroad trestle. The ou
lagoon is dredged periodically by SDG&E to ensure a good flow
clear water through the plant's cooling system. The sand
consists of "flour sand" which is discharged directly onto
beaches south of the inlet jetties where it sticks until st
waves carry it away. Because Aqua Hedionda is dred
periodically to a depth of about 16 feet, tBe sediment is alm
all ocean sand and not mixed with silt. The outer lag
provided an average 78 115,575 cubic yards of sand per y
between 1955 and 1972.
The inner Aqua Hedionda Lagoon is that portion east of 1-5.
sand bar consisting of about 30,000 cubic yards of sediment
formed at the west end of the lagoon. How much of this
useable beach sand and how much is land-fill mud is unkno
This y8terial is deposited at the rate of 13,000 cubic yards
year.
In summary, Aqua Hedionda Lagoon has available for initial be
replenishment some 30,000 cubic yards of material plus
undetermined materials around the periphery of the inner lago
plus the undetermined materials of the middle lagoon sandt
For annual beach maintenance it could provide 115,000 cubic YE
from the outer lagoon, 13,000 cubic yards from the inner lagc
and an unestimated quantity of beach sand from the middle lac - more than 128,000 cubic yards per year.
Depending upon which lagoon enhancement plan is selected, BE
quitos Lagoon could provide an initial 3,400,000 cubic yards
beach sand after the removal of some 581,000 cubic yards of f
silt which should go into landfill. Thereafter, the propc
sediment basin at the east end could provide about 1,000 CL
yards of beach sand per year. If the tidal prism method
keeping Batiquitos Lagoon is used successfully, there would
APPENDIX
I 0 w
-
little or no synd available for beach replenishment from the I
of the lagoon.
In short, the total maximum estimated capability of Carlsba
lagoons to nourish Carlsbad's beachhes averages, per year:
Buena Vista 15,385 cubic yards per year Aqua Hedionda 128,000 cubic yards per year Batiquitos 1,000 cubic yards per year
SAND DISPOSAL SITES
The net annual movement of sand along Carlsbad's beaches is f
north to south at the rate of about 280,000 cubic yards per ye
It, therefore, seems logical to deposit beach replenishment E at the north end in order to obtain the full use of it as
migrates south toward La Jolla Canyon.
To transport sand to Carlsbad's side of the Buena Vista weir I
the proposed siltation basins at the east end of Batiqui
Lagoon is a trip of 9 or 10 miles by highway. A hydraulic pi
line would probably follow about the same route. SDG&E would
reluctant to pump dredge spoil from Aqua Hedionda Lagoon nortt
the entrance jetties, since it is probable that sand north of jetties drifts into the entrance channel and forms the sand
just inside the lagoon.
For these reasons, it seems logical to deposit sand from
lagoons on the beaches nearest them. This would be n
economical in terms of transportation costs, and would also c;
fewer ecological and other environmental disruptions
objections. Therefore, Buena Vista sand should be deposited
Carlsbad's northernmost beach; Aqua Hedionda sand should
deposited on the beach south of the inlet jetties, and Batiquj
sand could be carried perhaps as far north as Ponto.
Since the City of Carlsbad owns none of these beaches, permiss
to replenish them would involve negotiations with a number
regulatory agencies, and include also the property owners wt
beaches would be affected.
TRANSPORTATION OF SAND
The two most common methods of transporting sand from lagoon
beach are trucking and hydraulic piping. It is also possible,
course, to pile it near the source.
APPENDIX
0 I
-f
In the case of Buena Vista, if the sand were to be deposited
Carlsbad's northern beach, a pipeline would probably be mc
appropriate. Similarly, the existing hydraulic pipeline would
appropriate to move sand from Aqua Hedionda to the neai
beaches. The huge initial volume of sand from Batiquil
enhancement plans would probably be most easily and cheaply mo\
by pipeline. The small annual increments predicted from 1
eastern end of Batiquitos might be stored and then moved
truck.
The dredge used by SDG8tE can be disassembled and installed in
of Carlsbad's lagoons. SDG&E is considering leasing it dur
the long intervals when it is not needed to clear the channel
Aqua Hedionda. Other, smaller dredges are available for close
work near the bridges. They would probably need booster pumps
the sand is to be transported any great distance. The SD
dredge can be used as a booster to move fluidized sand for ab
two miles. a
COSTS OF SAND
The consensus of opinions is that it costs around $4/cubic y
to move sand by hydraulic dredge, and if a booster pump is nee
to increase the distance of transport, additional costs
incurred. Some of that expense can be offset by selling
sand,,,;gich has been estimated to be worth about $2.50 per cu
yard. There remains the problem of determining who owns
sand, and who wants it?
FUNDING BEACH NOURISHMENT
Beach replenishment is an expensive proposition. Some sources
funds, guch as federal grants, are expected to dry up in the r
future. Although the Corps of Engineers has funds for proje
which are restorations of former conditions, Carlsbad's beac
may not meet that criterion; historically, they have been nar
and cobbled,
State funds come through various agencies, but the Parks
Recreation Department is generally opposed to impeding the cou
of nature, so they might offer significant opposition
replenishing Carlsbad's beaches, most of which come under tt
jurisdiction.
The newest regional consortium, BEACh, may in the future pro\
some funding, but lagoon manipulation might be considered a 1(
problem not sufficiently rewarding to the entire Ocean:
littoral cell.
APPEND I X
: 18 0 v
-
Because Carlsbad City owns no beach, it will be difficult
overcome taxpayer resistance to spending city funds to restc
beaches. If the city were to attempt funding, two aveni
suggest significant possibilities. Formation of a Commun;
Facilities District such as was contemplated for Oceanside wok
provide varyingl.+ax rates depending on the distaqSe of propel
from the beach. The Sand Rights legal doctrine could enat
the City to obtain or sell lagoon sand. Finally, beachfrr.
property owners might be required to finance their own be:
nourishement.
ENVIRONMENTAL CONSIDERATIONS
The "natural" historical condition of these lagoons--bef
Western Man interfered with them--was as river mouths empty
into the sea during winter rains and floods. Often they w
brackish marshes when a sand berm built up blocking the ri
mouth during summertime and dry periods. The rivers then
freshwater flora and fauna.
Buena Vista Lagoon has been restored to a brackish, freshwa habitat; the other two have not. The question arises, what
the Proper condition of these lagoons? Pre-historic, fr
flowing fresh water? Free-flowing tidal prism ocean estuary?
their "current" condition?
"Current" conditions include riparian eastern ends, fresh wa
marsh, salt water marsh, mud flats, saltwater sports areas, an
tidal prism channel.
The biological resources of a "restored" lagoon,4are described
the appraisal report for Aqua Hedionda Lagoon . They incl
pickleweed, various indigenous plants on the banks, and eelgr underwater. They include some 55 species of water birds and
species of land birds, including some rare or endangered speci
44 species of fish, untold species of clams and other underwa
invertebrates, and some cultural resources in archaeologi
sites.
Impacting on this ecological community are human activiti
including water sports and industrial use of the water.
In his presentation "Are Estuaries Really Necessary?", Ogle
commented in 1973:
"All the food organisms that man takes from estuarie
are dependent upon the integrity of the salt marsh--E
grass mudflat system, known as the DETRITUS FOOD CHB
Disruption of the detritus food chain will diminish i
APPENDIX
k '1 0 T
-
fisheries dependent upon estuaries ... once wetlands
tidal flats are destroyed, they can be regained only great expense. I11 2
ENVIRONMENTALIST REACTIONS
Envrionmentalist rections to any proposed modification of
status quo can be expected to be varied and intense. The gro
will not always focus on the same perceived problem, nor w
their positions always be complementary.
The California Coastal Commission in 1981 adopted a "Statew
interpretive guideline for wetlands and other wet environmenta
sensitive habitat areas." This requires an exhaustive effort
determine the answers to pertinent questions, and2 to prop
remedial answers to unsatisfactory perceived results.
The Batiquitos Lagoon Enhancement Plan of 19853 includes a 1
sequential list of steps necessary in the formulation
execution of a modification to a lagoon. It cites the agenc
from whom agreement and/or permits are necessary before a p
can be implemented.
The plan also suggests sources of funds for lagoon modificatio
As was evident in the Batiquitos Lagoon hearings, after all
necessary criteria have been met, there will still be m
challenges to the results. An EIR will not quiet
environmental uproar.
OTHER INLAND SOURCES OF SAND
Since the rivers have been dammed, sediment has been accumulat
behind the dams. According to Dr. Douglas Inman, the state
the art now can enable the removal of this sediment and
transport downstream. This sediment is the same sand and gr:
which used to be discharged onto the beaches by the rivers. F
the sandpiles below the dams, trucks could haul the sand
Carlsbad. The approximate mileage from various dams to Carl2
is:
Calavera Lake 6
Lake San Marcos 11
Lake Hodges 18
Dixon Lake 21
Lake Wohlford 23
Lake Sutherland 41
Lake Henshaw 47
APPENDIX
. <t 1 0 v
I -
Flood control basins are another inland source of be;
materials. These catchments fill up with sand and gravel 4
have to be cleaned out. In Los Angeles County, the Engini
trucks this siltation to county beaches, where the ocean conve. it to beach sand.
R E C 0 M ME,N D A T I 0 N S
1. The sediment in Carlsbad's lagoons should be used to coml
erosion on Carlsbad's beaches.
2. By programmed, selective removal of lagoon siltation,
broad beach could be established and thereafter nouris
periodically from the lagoons.
3. While providing beach nourishment, lagoons could be modif
to meet popular demands ranging from "natural" conditi
to water-sports/picnic areas.
4. A planned program should be initiated to continue
maintenance of the lagoons and the replenishment of
beaches in the future.
5, Funding for lagoon/beach enhancement should be sought f
agencies outside Carlsbad. It is unlikely that reside
could be persuaded to support the expensive, long-rE
program.
6. A permanent commission should be formed to oversee
beach/lagoon enhancement program. It should be broad-bas
including residents, merchants, hoteliers, enginee
financiers, sportsmen,and environmentalists.
APPENDIX
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0 L (' ,
REFERENCES
1. Applegate, J. & ASSOC., & Williams, P. & Assoc. 1985. Bu
Vista Lagoon Watershed Sediment Control Plan. (Califor
State Coastal Conservancy).
2. California Coastal Commission. 1981. Statewide Interpret
Guideline For Wetlands and Other Wet Environmenta
Sensitive Habitat Areas.
3. California State Coastal Conservancy. 1985. Batiqui
Lagoon Enhancement Plan.
4. City of Carlsbad Planning Department. 1976. Dr
Environmental Impact Report. Aqua Hedionda Lagoon Speci
Plan.
5. City of Carlsbad. 1976. Aqua Hedionda Specific Plan.
6. City of Carlsbad. 1980. EIR for Buena Vista Desiltation.
7. City of Carlsbad. 1982. Aqua Hedionda Land Use Plan.
8. Dyson, Bill. 1985. Comments during dredge tour, Nov.
1985. (Dyson is Project Officer for SDG&E dredging).
9. Griggs, G., & Savoy, L., Editors. 1985. Living With
California Coast.
10. Komar, P.D. 1976. Beach Processes and Sedimentation.
11. Noble, I?. 1985(?). Community Facilities District for Be
Facilities, Oceanside Pier. (Cost Estimates).
12. Oglesby, L.C. 1973. Are Estuaries Really Necessary?
13. Stone, K.E., & Kaufman, B. 1985. Sand Rights. A Le
System to Protect "The Shores of the Sea".
14. U.S. Army Corps of Engineers. 1985. Appraisal Report
Aqua Hedionda Lagoon. Carlsbad, California.
APPENDIX I
b W' 4 4P W
2/20/a
Carlsb
Dear Mario:
This will serve as my input to the Carlsbad Beach Erosion Commi
tee report to the Carlsbad City Council. It is not intended tt-
this be a stand alone document, rather that it be incorporal
into the committee's final report. It may, however, be incluc
as an appendix.
The following paragraph will summarize my recommendations to '
committee:
A, The beach communities along the Oceanside littoral ce'
under the supervision of their respective city and COUI
governments and with guidance from appropriate sti
agencies, from a joint committee empowered to:
1. Superficially investigate the beach erosion problems
the Oceanside littoral cell.
2. Identify sources of funds available for dealing w.
beach erosion problems.
3. Using funds available from No. 2, engage the services
coastal processes experts (science, engineering, leg
so that they may closely examine the problems
possible solutions (if any) of the Oceanside cell.
4. Submit the conclusion and recommendation of the ab
consultants to the resp&ive city and county governme
for appropriate follow up action.
B. Short term action:
1. The City of Carlsbad independently, or in conjunct
with the state or other neighboring communities, und
take a program of beach profile surveying. This data
essential to any long term study.
2. The City of Carlsbad retain the services of a coas
processes expert to advise the City on the distribut
of lagoon dredging materials along the Carlsbad coast
APPE
c .* 6 e W
If any of the above recommendations will be considered by t
City, then the committee will have made a major contribution
understanding the processes that influence the beach behavj
along the Oceanside littoral cell.
The problems and difficulties experienced by the City of Carlst
beaches have been adequately described in reports the Committ
has amassed throughout its tenure. In addition, numerc
speakers have discussed the phenomenon responsible for t
present state of this fragile land-sea interface. Since tk
information will be presented in the appendix, it will not
repeated here. It is interesting to note, however, that t
accumulated evidence points to man's interference with naturi
processes as the cause of the semi-permanent state of denul
beaches that we witness today.
The problems of the coast line along the Carlsbad City beacl
are the problems of the Oceanside littoral cell. These problc
are shared by the communities to the north and south of Carlsb,
It is the consensus of many experts in the field of coas
studies and civil engineering in the oceans that technical
administratively and operationallly these problems must
considered in the context of the activities of the whole ce
Proposed solutions, which may or may not benefit one area,
more than likely to effect beach responses in neigh-boring zonc
There is ample evidence that a piece-meal approach
compartmentalized solutions will eventually have detrimen
results on the problem as a whole. The committee report mi
emphasize the fact that from a technical, functional and ope
tional aspect the problems of the cell are shared by all the c
communities. Unilaterial solutions by individual entities w
likely act to exacerbate the existing problems. This has b
demonstrated on both a macro scale where individual be
property owners have acted to protect their investment to
detriment of their fellow property owners and on a global sc
where projects undertaken by one city have deprived the next c
of the natural sediment replenishment process.
If the problems off the Oceanside cell are to be solved by
cell communities, it is essential that these communities b
together to form a cohesive political body. It is only thro
this kind of political unity that sufficient resources may
brought to bear on the issue. Emphasis on this approach may
the greatest contribution this committee may make to the C
Council. A logical progression may involve the following step
A. Form a consortium of coastal Communities effected by the c
(such as BEACh).
APPE
e a&& i, v
8. This body appoint, engage or hire a yroup of beach proce
experts to conduct a long term comprehensive study into t
problems and possible solutions of the Oceanside littor
cell.
These consultants should have a proven track record and shot
involve professionals from the academic and engineering fie1
To be successful, these individuals must be provided with cle
and definite objectives. Their recommendations should
returned within a reasonable time frame. It must be recognize
however, that there is a distinct possibility that there exis
no economically feasible or practical solution to the beE
erosion problems as we now perceive them.
There are two other near term issues which must be addressed.
determine the scope and magnitude of the beach problems invesi
gators must have a comprehensive data base. This is a:
necessary for determining the effectiveness of any implemeni solution. Unfortunately, there is very little data wh.
describes beach behavior along the cell. The situation, w.
respect to wave climate, is somewhat better but could Sti
improvement. It is strongly reecommended that the C.
immediately embark upon a program of surveying the local be;
profiles.
The issue of lagoon dredged sediment distribution must
resolved. It is recommended that the City of Carlsbad immec ately engage the services of coastal experts so that they I
determine the spacial and temporal distribution of this sp material. This is not a large or complicated task and could
completed in short order.
DAVE CASTEL
DC:lch
APPEF