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HomeMy WebLinkAbout1986-05-20; City Council; 8617-1; Implementation of the Beach Erosion Committe Report'b 4 p I 0 Y 8 Lt: e Q cc .. z 0 6 $ a z 3 0 0 ClTPF CARLSBAD - AGENDeiLL ax I AB# x& Ir7-+/ TITLE: DEP MTG. 5/20/86 IMPLEMENTATION OF THE CITY BEACH EROSION COMMITTEE REPORT DEPT. CM CITY RECOMMENDED ACTION: By motion, adopt recommendations directing staff and/or Beach Erosion Committee to implement the proposals contai in this Agenda Bill. ITEM EXPLANATION On May 6, 1986 the City Council heard the report by the Be Erosion Committee which had been commissioned by the Coun in September of 1985. By motion, the Council received report, continued the existence of the Beach Erosion Commit with its existing members and City staff, and requested st to bring to the Council recommendations for implementation the report. The following are the recommended actions, extracted from the report: 1. City Council should substitute the existing Beach Eros Committee for the permanent committee as outlined Recommendation No. 3 of the report. Committee to meet the direction of the BEACh representative, but not 1 than quarterly to review new developments in be erosion, formulate strategies, and make suggestions to applicable persons, agencies or powers. Said committee be composed of no less than three (3) active members f the community and two appropriate staff members. 2. The Beach Erosion Committee should be charged with responsibility of researching the availability, co3J work program of a professional consultant or firn conduct a series of beach profile surveys yearly. Th surveys should provide data necessary for general public information projects, to determine where best place sand nourishment and how, and as a source of c for BEACh. 3. The Beach Erosion Committee should be charged with task of obtaining possible existing data on the E content of the middle and inner lagoons at Aqua Hedior and furthermore to work in cooperation with SDG&E and Army Corps of Engineers on the proposed project to dre those lagoon areas. Such data will be useful in provic recommendations on the placement of sand upon beaches. 4. The BEACh representative from the City Council shoulc given support to continue in his/her efforts to orgar the BEACh organization. 0 * ir, 4 Page 2 of Agenda Bill No. Jb/7-&/ 5. And finally, the Beach Erosion Committee should be char! with the responsibility to continue to monitor areas interest to the City such as beach erosion fundj sources, sand rights legislation, bluff protectj projects, and seminar or convention participation on SI topics as the Oceanside Littoral Cell, etc., and repr such significant developments to the Council in a time manner. FISCAL IMPACT None at the present time. However, the potential for futt expenditures will be created by this Agenda Bill regard beach profile surveys, sand coring samples, and possi participation in conferences or seminars, either independen or in conjunction with BEACh. EXHIBIT 1. Agenda Bill No. 8617. Note: If approved, the City Manager will assign Mike Brooks, Admini Assistant in Engineering to work with the Committee. Chris Sa will also meet with the Committee to consider including this wor the Redevelopment Program. r ' G .I4 0 z rl u rd U G QI 2 .rl M G *I4 W Fc M Fc G -d (d Fc 0 u -4 (d 9) 0 u fi F: 5; GO =rW .rl G 3 ,: Fcg h(d UG QIaJ 00 uo 9) WFc QI om FcU u9) QIU 2 3 3QI uu mo I (60 us WU cd cno a co I rD I m .. z 0 E a d 0 2 3 0 0 I Cl..e()OF CARLSBAD - AGENWBILL AB# 8% 17 TITLE: DEP CIT'r MTG. 5/6/86 BEACH EROSION COMMITTEE REPORT DEPT. CM CIT'r 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 erosj the problems of the Carlsbad coast line. At that time, tt Council charged the committee with delivering a report t you on/or about six months later. The following scope ( was outlined: 1. To review prior studies, articles, and materials. 2. To obtain current irlput from available sources. 3. To enumerate, evaluate, and study the beach erosion pi specific to Carlsbad's coast line. 4. To relate and coordinate the lagoon and coastal I area. 5. To develop plausible solutions to mitigate the beach problems and identify possible sources of funding. 6. To report these findings to the City Council. The letter of transmittal and report with attachments atta this agenda bill is the result of the Beach Erosion Comm efforts over the past half-year and is presented forthw your evaluation. EXHIBITS 1. Letter of transmittal from Mario Monroy, Committee Ch, dated March 28, 1986. 2. Carlsbad Beach Erasion Report , EXHIBIT 1 i 0 0 7 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 ar 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 befol building permits are granted for dams in CaliPornia rivei they be required to include plans for sand bypass ai transport to the beaches as part of the architecturi design. 7. The City Council, through BEACh, should sponsor region conferences on coastal erosion. 8. The City Council should continue to protect the bluf from erosion. 9. The City Council should finance coring of the Ag Hedionda Lagoon to determine sand content for future bea nourishment. 10. The City Council should adopt a policy that insures th any beach quality material dredged from City lagoa should be placed on beaches within the City only. r f e 0 City Council Carlsbad Beach Erosion Committee Report March 28, 1986 Page: 2 11. The City Council should lobby through our electec officials in Sacramento for recognition by the State Park: and Recreation Department of added recreational value 01 Southern California beaches because of the warmer air anc water. 12. The City Council should pursue the formation of BEACh eve1 if all of the originally proposed members do noi participate. The principles of BEACh are essential to thc solutions to beach erosion. MRM:lch txN\D t e 0 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 exF input from those listed below on their respective subjects: Ron Flick Oceanographer for the California Departmeni Boating and Waterways assigned to Scr Institute of Oceanography - "Sea Level and Effects on Beaches and Erosion." Bill Fait State Department of Parks and Recreai -Policies. Dan Muslin Army Corps of Engineers - Projects the Cc has worked on in Southern California. Douglas Inman Director 9 Center for Coastal Studies, Scr Institute of Oceanography - "History of C8 fornia Beaches." W. G. Dyson SDG&E - Dredging Aqua Hedionda Lagoon E. Aguardo Professor of Geography, San Diego S 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 respo bility for funding mitigation of beach erosion at Oceans This erosion was caused by the construction of the Del Mar Basin on Camp Pendleton in 1942 (see Figure 2). The Del jetties have interfered with the gross longshore transpor 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 nunderstood, detailed studies of the Carlsbad bea have not bee made. Even minor changes in the weather, tides wave patterns can have significant effects on sand flow, mE it almost impossible to determine what is happening in spec areas. !il,% r 0 0 - This interference with the natural course of sand flow has t 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 Hensh$w dam and in the SE Margarita River since 1949 by Vail Lake. In the period between 1957 and 1961 the Federal Governn further aggravated beach erosion to the south of the Del Mar r 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 i further offshore. These harbor jetties have interfered with net southerly migration of about 260,000 cubic yards of sand year in the Oceanside Littoral Cell. The Federal Government not assumed responsibility for the effects of longshore : transport south of Oceanside. Over the past 25 years between 1957 and 1982, about 11 mil. cubic yards of material has been dredged from Oceanside Hal and placed on Oceanside beaches. However, this sand nourish1 program was not as effective as it could have been because breakwater had a double effect. First it was trapping more : north of the harbor and secondly the longshore transport CI pick up sand in the newly nourished beaches south of breakwater. This, to the benefit of Carlsbad's beaches, a 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 du their cycles,with the sand completely eroded during the storm 1983. In subsequent summers, sand deposition on Carlsbad bea has been minimal. Prior to 1978 - 1979 Carlsbad had beaches, at least in the n 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 thick of sand of only three feet during the summer. (See Appendix A The fact that Oceanside hasn't done any sand nourishment s 1982 may prolong the recovery period for the Carlsbad beac Consequently, until Oceanside resumes a sand replenish program the damage to Carlsbad beaches and bluffs by mild st could be severe. At the present time, due to the lack of b profile data, it is not known whether the sand is offshore a the past to nourish the beaches naturally in the summer. there is no sand offshore, which is likely because of a long I f e * - 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 develo for dredging the Batiquitos Lagoon which could provide as much 2.5 million cubic yards of sand. This is enough to lay a blan of sand 5.3 miles long, six feet deep and 400-feet wide. T 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 bec progressively steeper to the south. If this is the case, southern beaches are unlikely to retain sand for any length time, Another source ,of sand, of course, is the Aqua Hedionda Lago This consists of outer, inner and middle lagoons. The in lagoon is east of 1-5 and the middle lagoon is between 1-5 the railroad trestle, The outer lagoon which is dred periodically by SDG&E has furnished an average of 116,000 cu 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 Ocean: Sand Bypass, if effective. This bypass is an experimental sy~ in its development stages which will be monitored for five YE by the Corps of Engineers. Therefore, this source of replenj ment may take some time to affect Carlsbad beaches. The syst if successful, will have the capacity to move 400,000 cubic YE of sand per year. However, the sand replenishment coulc 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 1 million. If the Oceanside sand bypass is not effective it may be neces: to build structures to retain sand and protect property, bli and highyays. Studies for Oceanside by the U. S. Army Corp: Enginee3s and by consultants Douglas L. Inman and Scott Jenkins have considered various types of structures. SI Table I. The review of these studies shows that, besides sand bypass, serious consideration for protection of the beai has been given only to groins and offshore breakwaters. Inman-Jenkins study suggested a series of groins, some tempor while the Corps of Engineers favored an offshore breakwa Based upon the similarities between Oceanside and Carlsba combination of these types of structures could be a possibi I I e e - 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 Sthe dams sho be a legitimate part of the cost of using water." There eppears 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 Dj state beaches also provide an extremely important recreat facility because of the warm air and waters in this area. 1 policy has the highest impact on the youth and lower inc population. CONCLUSIONS ?. Sand on the beaches is the best protection against bi erosion and property damage. 2. Protecting beaches and property solely by sand nourishmen an expensive way to accomplish this because replenish1 must be renewed again and again to be effective. 3. Douglas L. Inman stated that there are only about fif years of sand supply on the beaches north of the Ocean 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, offs breakwaters by their nature will severely affect the s interfere with boating and diving, and can be politic unpopular, as Oceanside found out. 5. Although groins are effective in retaining sand longshore littoral transport, 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. 1 V e 0 - 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 shortage. 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) wc be through a regional organization such as BEACh which political clout. 9. In discussions with the State Parks and Recreation Dep: ment, it becomes evident that funding to mitigate bt erosion is a low priority within this agency. RECOHUENDATIONS 1. The City of Carlsbad should continue to support the Bt Joint Powers Agreement and SANDAG's subcommittee on bc erosion. Without the political clout of a regional appro; it is impossible to compete for a share of funding frc 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 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 agen and to the public that the city recognizes the econ impact of erosion. c. The profile data would help the city to determine w best to place sand nourishment from the lagoons determine the effectiveness of any nourishment projec d. These survey results would be a source of valuable for BEACh. 3. The City Council should establish a permanent Beach Ero Committee consisting of no more than three citizens and city staff, one from Engineering, and one from Buildir 1 I 0 0 -( Planning. This committee should also serve as an advisor the City Council's representative on BEACh. 4. Through BEACh, the City Council should become direcl involved in conducting necessary public information : education on beach erosion and its solutions. 5. The City Council should work through BEACh in the contin development of "sand rights" under the Public Trust Law 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 pl 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 blL 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 Hedia inner and middle lagoons to determine their sand content future beach nourishment. 10. The City Council should adopt a policy that ensures that beach quality material dredged from City lagoons shoulc placed on beaches within the City. 11. The City Council should lobby through our elected offic: in Sacramento for recognition by the State Parks and Reci tion Department that the warmer air and water of San D. Coastal State beaches gives them an added recreational vi not available in the north. At the present time there i: funding for the restoration of southern public beact Under their present funding priorities the Parks and Reci tion Department is not carrying out its responsibilitie: the fullest. BEACh and SANDAG should support the Cit] Carlsbad on this point. 12. The beach communities under the supervision of their res1 tive county and city governments and with guidance appropriate state and local agencies from a joint commi empowered to: A. Superficially investigate the beach erosion problem the Oceanside littoral cell. I I a 0 - B. Engage the services of coastal process expe (scientific, engi neering, legal and administrative) that they may closely examine the problems and possi solutions for the Oceanside lottoral cell. 7, & kQ&U*I/ DAVID CASTEL SALLY VIGIC GZiL2Q.e.- PEARL E. 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STATE FUNDS A. State Lands Commission B. 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. 0. Direct Congressional funding. 111. REGIONAL FINANCING ALTERNATIVES A. Assessments 8. Fees C. Taxes D. Bonds IV. CARLSBAD: Transient occupancy tax V. UTILITY COMPANY - SAN DIEGO GAS & ELECTRIC x L 0 0 TABLE 111 BEACH SAND LEVEL MEASiUREMENTS Carlsbad, California I. 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 I I I - - I ! ! ! i I I - i ! I B i ! ~3t1 sin1 NVS $9 L2%\\ 514 i II P Hl:lB! ps 2????2? i . . . .. .. . .. .. .% , ’. ’ . .. . c w W LL 0 0 (1 0 4 18 2 4 z ‘X < W W m Q Q I 4 V z a .. I 0 0 - REFERENCES 1. Sea Cliffs, Beaches, and Coastal Valleys of San Diego Cour by Gerald G. Kuhn and Francis P. Shepard, 1984. 2. Progress Report on Beach Erosion Control Study, San Dj County, California in Vicinity of Oceanside by Los Ange District U. S. Army Corps of Engineers, January 1977. 3. Oceanographic Report for Oceanside Beach Facilit Prepared for the City of Oceanside by Douglas L. Inman Scott A. Jenkins, 1983. 4. Putting the Beach Back at the Oceanside. A Case Stud) Locally Initiated Beach Restoration, by Larry M. Bagley Dana H. Whitson. Journal of the American Shore and 81 Preservation Association. Vol. 50, No. 4, October 1982. 5. Budget of Sediment in Southern California: River Disch versus Cliff Erosion by Douglas L. Inman. Californ Battered Coast. Proceedings from A Conference on Coa Erosion, San Diego, February 6-8, 1985, pg. IO. 6. Beach Erosion - A Planning Perspective and Appendix Secre for Resources Policy for Shoreline Erosion Protection. S Parks and Recreation Department. 7. Shore Protection Manuals, Volumes I and 11, U. S. Army C of Engineers, 1984. 8. Oceanographic Report for Community Facility District Beach Facilities for the City of Oceanside, Douglas Inman, July 21, 1983. 0 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, 8, C, D and E on enclosed map. Also, note cha citing deepwater direction and shore erosion from Santa Marqar River to Aqua Hedionda Laqoon. Finally, only each area's uni features pertinent t o erosion are described along with con characteristics. Common Characteristics - Beach areas A, B, half of C, D and half or most of E lie at bi of cliffs, popularly called The Bluffs. It all represents Santiago formation with terrace deposits on top. They con1 hard, gray clayey material and much silt sandstone. teri deposits are sand and cobbles. Silica sand and some mica noui beaches from lagoons and few remaining bluffs not yet forti by cement or rack. I. Area A is privately owned to mean high t'de mark - a v legal setting unchanged since 1967. (?I> Four pu accesses within six city blocks are city-owned maintained by Parks and Recreation, under jurisdictioi Carlsbad Police. Three accesss in addition are owned maintained by California Coastal Conservancy or pri property associations. All are heavily trafficked tourists, residents of Carlsbad (both townspeople and t living in beach structures as renters or owners) representing general public. All beach areas suff similar erosion problems plus cobbles, but Area A recov faster in 1983 for these reasons: A. Oceanside sand dredging replenishes Area A sooner. El. South to north littoral drift works well since 1 although there is some dispute as to whet??? or this has become variable since 1980. controversy needs study. C. Mild winter storm activity from 1983 until Nover 1985. APPENDI: e 0 e ?. Scripps predicts bad year as being 1987 and I or two others into year 2000. D. Experimental Longard Tube, financed by property ownr 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, pig 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 B, D and E are usually cobbled, Area A more users of beaches. 1. No lifeguards, no consistent maintenance supervisory authority other than police dul 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 c' in 1980 when massive building occurred: A. Sand is still the number one protection against b and erosion threatening bluffs and property. 6. At least erosion due to small animal burrowing solved by building. C. Individual storm drains should be at street level, APPEND1 J e 0 -- D. Cobbles hold sand but endanger property too. E. Most suprising to engineers is the fact that otl areas may not be at all like Area A nor like e pfyer. (Not all have been surveyed geologicall 1. Some bluff areas seem to be edrock but crum ( 44 when wet as in rain erosion. 2. Areas D, C and E are mostly sandstone with s mica. 111. Storms of 1983 coincided with rare high wave action 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 astronornica component of extreme tides still w( exceed those of 1982-83 by more than 0.06 -0,09M# This can give room for hope plus incentive to ret1 as to remedies. Since in fifteen years there will no more 290,000 cubic yards per year drifting 1 Oceanside to be lost in La Jolla Canyon and - Carl Canyon, entrapment and recycling of dredged sanc Aqua Hedionda must be a long term option and in 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 ero at north end of Carlsbad beach called The Point. 1. The sand return by summer has been the bes all beaches. 2. November and February storms of 1986 c; breakdown of weir as water poured over ocean. (See news picture.) Released sand st be observed and monitored. C. St. Malo development (north of lagoon and across to Oceanside) has properly designed rock revet according to Dr. Doug Inman. APPEND1 a e - 1. Protects propety without (gyusing scouring sand, thus negligible loss. D. Inman suggestion: Original Scripps study of s drift can continue or be reinstated while sand stor is pondered, especially that from Batiquitos Laqoon 1. The Point at Buena Vista outlet to the sea is good spot since sand Flaced further north ta longer to drift south and should be retained recycled on a short term plan as suggested 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 F Hedionda. Better use should be made of ii recycling at dredging period. As examplf should be stored in berm on and against bluff: (7) 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 , called Tamarack, maintained by Parks and Recreation witi structures left on beach since 1980-83 storms. State p. no remedial improvements even though replenishment of i was fairly good summers 1983-84. In those summers, bc was comparatively unused because of poor access and par1 limitations. A. Beach 8 terminates at jetty at Aqua Hedionda and p plant. 1. Lagoon used by power plant as cooling out also is popular small boat and fishing area. 8. Sandy beach due to proximity to jetty at tim dredging lies south of second jetty. C. Third jetty is at sewage disposal just before Carl Submarine Canyon. APPENDIX e 0 e 1. No jetty is extended enough to trap sand. 2. C""Y$?) controversial as to whether enlarging 0. Committee agreed that cost of dredging could be E not. as cost of jetty extensions. 1. January dredging does not help sand retent because of st@r)ms. Dredging no help witt- south jetties. 2. Dredging could be done more often at right t. 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 ni of jetties, or even north OF Batiquitos Lagoon in south-north return of sand enters lagoon. B. Official tate lack of desire for Oceanside by-1 $9 P to work. AREA C AND HALF OF D I. Flats to bluffs to flats again describe the beaches, o in part by private home owners at beach area ca Terramar and Carlsbad State Beach also called S Carlsbad and Ponto Beaches. A. Sea cliffs with narrow, fragile beach, mo 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 termir at sewage disposal. A. More cobbles and eroding bluffs. APPENDI) b (I) e - 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 Lagoon. St Parks and Recreation operate an R.V. park at the top bluffs. Storm drains severely gully bluff face and call landslides in 1980 and 1983. Road closed in 1983 cobbles moved on shor(elD) Flat beach subject to flooc from San Marcos Creek. Finally, at this writing, all beaches are cobbles because storms February 18, 1986. APPENDIX - m e BIBLIOGRAPHY 1. Flick, Ron, seminar with Beach Erosion Committee, Oct. 1985. 2. Griggs, Savoy, Livinq With The California Coast, C University Press, Durham, NC, 1985, p. 351. 2b. Kuhn, Gerald, Sea Cliffs, Beaches, Coastal Vallf University-Press, Los Angeles, CAY p. 63. 3. Moffatt & Nichols, Engineers, Long Beach, CA, Mr. Dunhan . Property Owners Area A, July, 1983. 4. Willard, Syd, Parks and Recreation Dept., State Geolog speech to Beach Erosion Conference, Santa Barbara, October 3, 1985. 5. Flick, Ron, Journal Waterway, Port, Coastal and Ocean, Enc Div., Amer. SOC. Civil Eng., 1984, to Carlsbad Commit' Oct. 3, 1985. 6. Inman, Doug, Scripps Oceanography, seminar at Carl: Committee meeting, Nov. 7, 1985. 7. Kuhn, Gerald, Sea Cliffs, Beaches, Coastal Valleys, San D County, University Press, Los Angeles, CA, p. 63. 8. Ulman, Dan, Corps of Engineers, to Committee meeting 1985. 9. Dyson, Bill, SDG&E to Erosion Committee, Dec. 12, 1985. IO. Griggs, Savoy, Living With The California Coast, University Press, Durham, NC, 1985, p. 351-53. APPENDIX COASTAL STORM[ AREAS I B?ld.AT STATE - SbGt - 1 WILSON ENGINEERING FIGURE ES - I - - - - - - - - - - - - 7 - 7 - - - - - 7 - T.2 , % -: e' .. - - - - 7 - - - - - - - - - - 7 - - - - - - - - - - - - - - - - - - :?. ; ', - - *= *= m= OG - - - - a= -= - - - - *= a= 7 b= - u= - - -= - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - c_ - 0- - \ / -\ * ;;;*za -3 *gz&s*G -5 E % .z E .s % c G75 c FSP &,kSR am P) U.d rnac m v) IC QQQ v) aal x u a. - c') f- to- - I 9 0 C A R L S B A D L A G 0 0 NI S SOURCE OF BEACH SAND REPLENISHMENT by John Gray IMPACT ON BEACH EROSION During most of the past 6,000 years, Carlsbad's lagoons deliv sand to the beaches. During the past two hundred years, howe Western Civilization has been interfering with this delive This condition is not peculiar to Carlsbd, though. throughout Southern California, beach materials are being trai by 311 water supply lakes and flood fjontrol reservoirs anc additional 77 sand and gravel quarries. DESCRIPTION OF CARLSBAD'S LAGOONS. Carlsbad's three lagoons are, from north to South, Buena Vi Aqua Hedionda, and Batiquitos. All three of them are bridge1 U.S. Highway 101, the railroad track, (and Interstate-5. Buena Vista Lagoon lies between Carlsbad and Oceanside. The limits are a zigzag line which gives the southern half of lagoon to Carlsbad. The entire lagooii is included in the Maxton Brown Bird Sanctuary. The watercshed of Buena Vista La consists of about 19 square miles within the cities of Vi Oceanside, and Carlsbad. Its principal source of water is E Vista Creek, rising in Vista. The lagolon is fresh water, kep by a fixed weir at the mouth of the lagoon. From the wei Jefferson Street on th? east, it is about 1.4 miles long, about 1/35 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 w t r about 200 acres of salt marsh, mud flats, and salt flats. is kept open to the sea by tidal action and periodic dredgin the outer lagoon by the San Diego Gas and Electric Con (SDG&E). Its principal source of fresh water is Aqua Hedj Creek, which drains a watershed from Vista, San Marcos, Calz Lake, and county lands to the south. Batiquitos Lagoon extends about 2-1/2 miles inland from the ( to Camino Real. It is about 1/2 mile wide. Its drainage t includes San Marcos Lake, San Marcos Creek, and Encinitas Crc B %% APPENDI) > e e - 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 Bu Vista Lagoon watershed sediment control plan. During the Pleistocene Epoch, Carlsbad's lagoons were r: valleys, draining into the sea. At the end of the Ice Age : 6,000 years ago, the ocean rose and flooded saltwater into tt river valleys. The river bottoms were covered with teri deposits--sand and gravel and silt whic:h had come down from watersheds. Such erosion continues up t.o this day. During summer months, a berm might be built up blocking the r. mouths, but during the rainy season, flood waters would bi through the berm, carrying sand and gravel to the beaches. Uf 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 Califorr Herds of grazing animals reduced the vegetation on the hillsic Then farmers cultivated the slopes and further denuded t' Then developers graded the slopes and highways were coverec mud slicks as rainstorms washed away the unprotected soil. stage of urbanization caused more erosion of the watersheds deposited more sand, gravel, and silt in the lagoons wl sedimentation could occur in the calm hlater. The lagoons si UP. When the developers built homes and paved streets in subdivisions the erosion process changed. There was not so 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 gr was carried into the lagoons where siltation continued to occ 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. T obstructions restricted the flow into the ocean, and the q water allowed even more silt to settle lout in the lagoons. Buena Vista Lagoon had a weir installed across its mouth in 1 This kept the ocean out until 1969 when a flood washed out weir. It was rebuilt in 1970 and Buena Vista Lagoon becamc APPENDIX > 0 0 - freshwater lake, except for sewage which was dumped into regularly until 1960 and spilked into it sporadically ever sin Buena Vista Lagoon silted up. The San Diego Gas and Electric company bought Aqua Hedio Lagoon, and commenced dredging it in 1952. Most of the follow information has been extracted from the U.?% Army Corps Engineers "Appraisal Report for Aqua 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 prj Nevertheless, SOGdtE has to c&edge the sand bar from the 01 lagoon about every two years. Most of the foliojwing was extracted from the Batiquitos Lac Enhancement Plan, In recent years, Batiquitos Lagoon has t mostly salt flats. It was open naturally most of the time ur the mid-'601s. Since then, it has been opened with a bulldc occasionally to let the stagnant waters out and thus ai flooding the sewage booster plant on the south side. The boi of Batiquitos Lagoon is covered with flLivial material, mostly sand and gravel, topped with a thin layer of clay and s Sedimentation of Batiquitos Lagoon increased rapidly as La C 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 b 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 bea Generally, an upper layer of silt, composed of clayey shales mudstones, will have to be disposed of before the sand useabl beaches can be dredged out. Most often such silt is used landfills, such as in the area just east of Jefferson Stree the former Buena Vista Lagoon. Again unfortunately, such cla not a stable platform for heavy construction. APPENDI) L > 0 0 - From Buena Vista Lagoon, it would be possible to dredge f 10,000 to 100,000 tons of sediment per year, but only 5% 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 2041 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 ir lagoons. No information is available on the contents of middle lagoon, between 1-5 and the railroad trestle. The o( lagoon is dredged periodically by SDG&E to ensure a good flor 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 si waves carry it away. Because Aqua Hedionda is drec periodically to a depth of about 16 feet, tbe sediment is all all ocean sand and not mixed with silt. The outer lac provided an average q& 115,575 cubic yards of sand per ; 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 unkn This rpgterial 'is deposited at the rate of 13,000 cubic yards year. In summary, Aqua Hedionda Lagoon has available for initial b replenishment some 30,000 cubic yards of material plus undetermined materials around the periphery of the inner lag plus the undetermined materials of the middle lagoon sand For annual beach maintenance it could provide 115,000 cubic y from the outer lagoon, 13,000 cubic yards from the inner lag and an unestimated quantity of beach sand from the middle la - more than 128,000 cubic yards per year. Depending upon which lagoon enhancement plan is selected, E quitos Lagoon could provide an initial 3,400,000 cubic yard beach sand after the removal of some 5Ei1,OOO cubic yards of silt which should go into landfill. Thereafter, the prop sediment basin at the east end could provide about 1,000 c yards of beach sand per year. If the tidal prism metho keeping Batiquitos Lagoon is used successfully, there would APPENDI) < . e 0 - little or no s nd available for beach replenishment from the r 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 Agua Hedionda 128,000 cubic yards per year Batiquitos 1,000 cubic yards per year 3 SAND DISPOSAL SITES The net annual movement of sand along Carlsbad's beaches is 1 north to south at the rate of about 280,000 cubic yards per YE It, therefore, seems logical to deposit beach replenishment : 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 1 the proposed siltation basins at the east end of Batiqui Lagoon is a trip of 9 or 10 miles by highway. A hydraulic p: line would probably follow about the same route. SDG&E woulc reluctant to pump dredge spoil from Aqua1 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 t.o deposit sand from lagoons on the beaches nearest them. This would be I economical in terms of transportation costs, and would also c fewer ecological and other environmental disruptions objections. Therefore, Buena Vista sand should be depositec Carlsbad's northernmost beach; Agua Hedionda sand should deposited on the beach south of the inlet jetties, and Batiqu sand could be carried perhaps as far north as Ponto. Since the City of Carlsbad owns none of these beaches, permis to replenish them would involve negotiations with a number regulatory agencies, and include also the property owners wI beaches would be affected. TRANSPORTATION OF SAND The two most common methods of transporting sand from lagoo beach are trucking and hydraulic piping. It is also possible course, to pile it near the source. APPENDIX < 9 e 0 - In the case of Buena Vista, if the sand were to be deposited Carlsbad's northern beach, a pipeline would probably be mi appropriate. Similarly, the existing hydraulic pipeline would appropriate to move sand from Aqua Hedionda to the nea beaches. The huge initial volume OF sand from Batiqui enhancement plans would probably be most easily and cheaply mo by pipeline. The small annual increments predicted from eastern end of Batiquitos might be stored and then moved truck. The dredge used by SDG&E 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 at two miles. a COSTS OF SAND The consensus of opinions is that it costs around $4/cubic ; to move sand by hydraulic dredge, and if a booster pump is net to increase the distance of transport, additional costs incurred. Some of that expense can be offset by selling sand,,$ich has been estimated to be worth about $2.50 per c yard. There remains the problem of determining who owns sand, and who wants it? FUNDING BEACH NOURISHMENT Beach replenishment is an expensive proposition. Some source funds, guch as federal grants, are expected to dry up in the future. Although the Corps of Engineers has funds for proj which are restorations of former conditions, Carlsbad's bea may not meet that criterion; historically, they have been na and cobbled. State funds come through various agencies, but the Parks Recreation Department is generally 0ppo:jed to impeding the co of nature, so they might offer significant opposition replenishing Carlsbad's beaches, most of which come under t jurisdiction. The newest regional consortium, BEACh, may in the future pro some funding, but lagoon manipulation might be considered a 3 problem not sufficiently rewarding to the entire Ocear littoral cell. APPEND11 it 9 0 0 - Because Carlsbad City owns no beach, it will be difficult overcome taxpayer resistance to spending city funds to rest beaches. If the city were to attempt funding, two aven suggest significant possibilities. Formation of a Commun Facilities District such as was contemplated for Oceanside wo provide varying.,+ax rates depending on the distaq5e of prope from the beach. The Sand Rights legal doctrine could ena the City to obtain or sell lagoon sa17d. Finally, beachfr property owners might be required to finance their own be nourishement. ENVIRONMENTAL C-ONSIDERATIONS 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 b brackish marshes when a sand berm built up blocking the r: mouth during summertime and dry periods. The rivers then freshwater flora and fauna. Buena Vista Lagoon has been restored to a brackish, freshw: habitat; the other two have not. The question arises, what the proper condition of these lagoons? Pre-historic, fi flowing fresh water? Free-flowing tidal prism ocean estuary? t he i r lrc u r r en t 'I con d it ion? "Current" conditions include riparian eastern ends, fresh w marsh, salt water marsh, mud flats, saltwater sports areas, a tidal prism channel. The biological resources of a "restored" lagoon14are describe1 the appraisal report for Aqua Hedionda Lagoon . They inc pickleweed, various indigenous plants on the banks, and eelg underwater. They include some 55 species of water birds an( species of land birds, including some rare or endangered spec 44 species of fish, untold species of clams and other underw invertebrates, and some cultural resources in archaeolog sites. Impacting on this ecological communit.y are human activit including water sports and industrial use of the water. In his presentation "Are Estuaries Really Necessary?", Ogl commented in 1973: "All the food organisms that man takes from estuari are dependent upon the integrity of the salt marsh-- grass mudflat system, known as the DETRITUS FOOD Ct Disruption of the detritus food chain will diminish APPENDI) 1 (r b 0 0 - fisheries dependent upon estuaries .. . once wetlands tidal flats are destroyed, they can be regained only great expense." 12 ENVIRONMENTALIST REACTIONS Envrionmentalist rections to any propclsed modification of status quo can be expected to be varied and intense. The gro will not always focus on the same perceived problem, nor k their positions always be complementary. The California Coastal Commission in 1981 adopted a "Stater interpretive guideline for wetlands and other wet environment: sensitive habitat areas." This requires an exhaustive effort determine the answers to pertinent questions, and2 to pro1 remedial answers to unsatisfactory perceived results. The Batiquitos Lagoon Enhancement Plan of 1~85~ includes a 1 sequential list of steps necessary in the formulation execution of a modification to a lagoon. It cites the agent from whom agreement and/or permits are necessary before a I can be implemented. The plan also suggests sources of funds for lagoon modificatic As was evident in the Batiquitos Lagoon hearings, after all necessary criteria have been met, there will still be 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 accumula behind the dams. According to Dr. Douglas Inman, the statc 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. the sandpiles below the dams, trucks could haul the sand Carlsbad. The approximate mileage from various dams to Carl is: Calavera Lake 6 Lake San Marcos 11 Dixon Lake 21 Lake Wohlford 23 Lake Sutherland 41 Lake Henshaw 47 Lake Hodges 18 APPENDIX , I* , Io * - Flood control basins are another inland source of be materials. These catchments fill up with sand and gravel have to be cleaned out. In Los Angeles County, the Engin 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 corn 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-ra 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 - - (C, e e REFERENCES 1. Applegate, J. & ASSOC., & Williams, P. & Assoc. 1985. Bu Vista Lagoon Watershed Sediment Ca'ntrol Plan. (Califor State Coastal Conservancy). 2. California Coastal Commission. 1981. Statewide Interpret Guideline For Wetlands and Ottier 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 far 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, R. 1985(?). Community Facilities District for 61 Facilities, Oceanside Pier. (Cost Estimates). 12. Oglesby, L.C. 1973. Are Estuaries Really Necessary? 13. Stone, K.E., & Kaufman, 6. 1985. Sand Rights. A 11 System to Protect "The Shores of the Sea". 14, U.S. Army Corps of Engineers. 1985. Appraisal Report Aqua Hedionda Lagoon. Carlsbad, California. APPEND1 X ' 4- * e e t 2/20/ Carls Dear Mario: This will serve as my input to the Carlsbad Beach Erosion Comm tee report to the Carlsbad City Council. It is not intended t this be a stand alone document, rather that it be incorpora into the committee's final report. It may, however, be inclu 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 COL governments and with guidance from appropriate st agencies, from a joint committee empowered to: 1. Superficially investigate the beach erosion problem: the Oceanside littoral cell. 2. Identify sources of funds available for dealing v beach erosion problems. 3. Using funds available from No. 2, engage the service: coastal processes experts (science, engineering, le5 so that they may closely examine the problems possible solutions (if any) of the Oceanside cell. 4. Submit the conclusion and recommendation of the at consultants to the resp&ive city and county governme for appropriate follow up action. 8. Short term action: I. The City of Carlsbad independently, or in conjunci with the state or other neighboring communities, unc take a program of beach profile surveying. This dat, essential to any long term stucly. 2. The City of Carlsbad retain the services of a coal processes expert to advise the City on the distribu of lagoon dredging materials along the Carlsbad coas' APPE a**, e I) If any of the above recommendations will be considered by City, then the committee will have made a major contributior understanding the processes that influence the beach behac along the Oceanside littoral cell. The problems and difficulties experienced by the City of CarlE beaches have been adequately described in reports the Commit has amassed throughout its tenure. In addition, nume1 speakers have discussed the phenomenon responsible for present state of this fragile land-sea interface. Since t information will be presented in the appendix, it will not repeated here. It is interesting to note, however, that accumulated evidence points to man's interference with natuI processes as the cause of the semi-permanent state of denL beaches that we' witness today. The problems of the coast line along the Carlsbad City beac are- the problems of the Oceanside littoral cell. These probl are shared by the communities to the north and south of Carlst It is the consensus of many experts in the field of coat 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 CF Proposed solutions, which may or may not benefit one area, more than likely to effect beach responses in neigh-boring zor There is ample evidence that a piece-meal approach compartmentalized solutions will eventually have detrimer results on the problem as a whole. The committee report n 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 v likely act to exacerbate the existing problems. This has t 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 t together to form a cohesive political body. It is only thrc this kind of political unity that sufficient resources ma) brought to bear on the issue. Emphasis on this approach ma) the greatest contribution this committee may make to the I Council. A logical progression may involve the following step A. Form a consortium of coastal communities effected by the c (such as BEACh). APPE ** *s e Q B. This body appoint, engage or hire a yroup of beach proc experts to conduct a long term comprehensive study into problems and possible solutions of the Oceanside litto cell, These consultants should have a proven track record and sho involve professionals from the academic and engineering fie To be successful, these individuals must be provided with cl and definite objectives. Their recommendations should returned within a reasonable time frame. It must be recogniz however, that there is a distinct possibility that there exi no economically feasible or practical solution to the be 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 inves gators must have a comprehensive data base. This is a necessary for determining the effectiveness of any implemer solution. Unfortunately, there is very little data wt describes beach behavior along the cell. The situation, b respect to wave climate, is somewhat better but could st improvement. It is strongly reecommended that the ( 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 imme ately engage the services of coastal experts so that they determine the spacial and temporal distribution of this SF material. This is not a large or complicated task and coulc completed in short order. DAVE CASTEL DC:lch APPE