STATE OF CALIFORNIA -- NATURAL RESOURCES AGENCY ARNOLD SCHWARZENEGGER, Governor CALIFORNIA COASTAL COMMISSION SOUTH CENTRAL COAST AREA 89 SOUTH CALIFORNIA ST., SUITE 200 VENTURA, CA 93001 Filed: 4/3/09 (805) 585-1800 180th Day: 9/30/09 Staff: S. Hudson Staff Report: 6/25/09 W 8b Hearing Date: 7/8/09 STAFF REPORT: REGULAR CALENDAR APPLICATION NO.: 4-08-006 APPLICANT: Santa Barbara County Parks Department AGENTS: Dave Ward, Santa Barbara County Planning and Development Department Chris Webb, Moffatt & Nichol McCabe and Company Chambers Group PROJECT LOCATION: Goleta Beach County Park at 5986 Sandspit Road, Santa Barbara County PROJECT DESCRIPTION: Construct an approximately 500 ft. long, 20 ft. wide, permeable pier sand retention system as an addition to the existing Goleta Beach Pier consisting of 250 – 330 timber or composite fiberglass piles (18” – 20” in diameter) and timber decking. The project also includes seasonal installation of an approximately 1,200 ft. long, 3-5 ft. high winter sand berm for a period of five years after initial development commences; removal of approximately 1,500 linear ft. of existing rock rip rap upcoast of the existing restaurant on site; repair of approximately 650 linear ft. of existing revetment at the downcoast end of the park, and offshore dredging of approximately 500,000 cu. yds. of sand and placement of dredged material on the beach immediately upcoast of the pier for the purpose of initial beach nourishment; and the implementation of an Adaptive Management and Monitoring Program that may include periodic adjustments to add or remove piles from the permeable pier sand retention system and periodic offshore dredging/beach nourishment on an as-needed basis not exceed 100,000 cu. yds. of material/year. MOTION & RESOLUTION: Page 8 SUMMARY OF STAFF RECOMMENDATION Staff recommends approval of the proposed development with 18 special conditions outlined on pages 9 - 30 of this staff report. The proposed permeable pier sand retention system and beach nourishment program presents complicated coastal resource, planning, and public policy issues and is proposed by the County of Santa Barbara as a solution to an on-going, long-term coastal erosion problem at Goleta CDP 4-08-006 (Santa Barbara County Department of Parks & Recreation) Page 2 Beach County Park that has generated tremendous public interest and controversy for many years. Following is a summary of the main issues raised by the project and how they are resolved by staff’s recommendation: The primary purpose of the proposed project is to create a widened public sandy beach at Goleta Beach County Park to reduce the potential for periodic wave-caused erosion to upland park areas and facilities and enhance public access and recreational opportunities while also maintaining existing sediment supplies to all areas downcoast of the project site to ensure that the project does not result in any increased erosion of downcoast beaches and bluffs. An approximately 1,500 linear ft. rock revetment has been constructed on the upcoast (western) portion of the park in response to the long- term shoreline erosion problem at Goleta Beach (Exhibit 2). Approximately 250 linear ft. of the existing 1,500 linear ft. revetment was installed in the 1980’s without the required coastal permit and an approximately 1,350 linear ft. portion of the revetment was constructed between 2002 – 2005 pursuant to the Commission’s approval of CDP 4-02-251 (as amended twice), which authorized that portion of the revetment on a temporary basis only until January 2008. Although authorization for the approximately 1,350 linear ft. portion of the revetment has expired, Special Condition One of CDP 4-02-051, as amended, also specifically required the applicant to obtain a new coastal permit for either removal or permanent authorization of the revetment. This application was submitted in January 2008, in compliance with the requirements of Special Condition One of CDP 4-02-051 (which specifically allowed the applicable timelines for removal of the revetment to be extended until the Commission acts on this pending application). As part of this project, the applicant is now proposing to remove the entire approximately 1,500 linear feet of rock revetment located on the upcoast (western) portion of the park (as shown on Exhibit 2). The primary issues raised by this project are: the need for the permeable pier sand retention system and the potential for the system to result in increased erosion of downcoast beaches and bluffs and changes in the frequency and duration of Goleta Slough mouth opening/closure events. With respect to the need for the system, opponents to the proposed project believe that feasible alternatives exist that would be environmentally preferable to this project, including the use of a “managed retreat” alternative. In regards to alternatives to the proposed project, both the applicant and the Environmental Defense Center (EDC), which is opposed to the proposed project, have both evaluated a range of managed retreat alternatives including full retreat beyond the expected range of wave attack, partial retreat with a new “backstop” revetment, and a managed retreat option without use of a rock revetment that would include a strategic reconfiguration of the facilities within the park to avoid or minimize the loss of any critical park uses such as parking facilities (Exhibit 18). Each of these managed retreat/reconfiguration options are relatively similar in that they would involve: (1) removal of approximately 1,500 linear ft. of as-built revetment on the upcoast end of the park, (2) retention of some or all of the existing rock revetment seaward of the existing restaurant and parking lot at the east (downcoast) end of the park and (3) provide for the removal and/or landward relocation of the seawardmost located existing facilities CDP 4-08-006 (Santa Barbara County Department of Parks & Recreation) Page 3 and structures within the park to minimize or avoid the potential of wave caused damage. However, each of the identified managed retreat alternatives would still result in the loss of approximately 1.3 acres of existing upland area within the park which would effectively be converted to sandy beach environment. Although this would not result in a reduction of actual park area, it would result in the conversion of upland recreational area to sandy beach recreational area. Moreover, if increased narrowing of the beach due to sea level rise occurs, then this expanded beach area would most likely be lost due to inundation in the future as well. Upland areas of the park that would be lost include portions of the grassy lawn area, picnic area, and parking lot areas. Although the managed retreat alternative is feasible and would avoid any potential adverse impacts to the marine environment and downcoast areas, this alternative would also result in the removal of approximately 1.3 acres of upland areas of the park that currently provide important public access and coastal recreational opportunities. In regards to potential downcoast effects of the project, the permeable pier sand retention system is designed to effectively function as a “permeable groin”. Similar to a regular groin, the proposed device will function by trapping sand on its upcoast side in order to create a wider beach condition. However, unlike a regular groin, the proposed “permeable pier sand retention system” is designed to be permeable allowing a percentage of the sand within the littoral system to pass through openings in the structure (the spaces between the piles), thus regulating the rate of sediment exchange, while maintaining current sand supply volumes for downcoast areas within the littoral cell. The permeable design of the structure is intended to avoid any additional erosion of downcoast beaches and bluffs. The County has submitted a coastal engineering analysis for the proposed project by their engineering consultant, Moffatt and Nichol, analyzing the potential downcoast effects of the project utilizing computer modeling. Based on the results of the modeling, the County’s engineering consultants predict that the project will not result in any significant increase in the rate of downcoast erosion of the shoreline and will not have any measurable effect on the frequency of openings or closures of the Goleta Slough mouth. However, the EDC, has also submitted an analysis by their engineering consultants, Philip Williams & Associates (PWA) disputing the results of the applicant’s modeling and asserting that the project would likely result in increased erosion of downcoast areas (Exhibit 19). Thus, there is clearly a disagreement between the engineering consultants retained by the County and the EDC regarding the adequacy of the modeling performed for the project and the potential effects of the project. Commission Staff Coastal Engineer, Lesley Ewing, has reviewed the results of the County’s modeling and the concerns raised by PWA and concluded that the modeling performed by the applicant’s engineering consultants is generally adequate from an engineering perspective although it must also be noted that all predictive models include some inherent possibility for error and can not guarantee certainty in regards to predicting the effects of any project. In addition, both the engineering consultants for the applicant and for the EDC agree that actual physical modeling should be performed prior to construction to CDP 4-08-006 (Santa Barbara County Department of Parks & Recreation) Page 4 ensure that the appropriate percentage of permeability is achieved and to ensure that downcoast erosion is avoided. Therefore, in order to ensure that the proposed permeable pier sand retention system is constructed in a manner that ensures downcoast erosion would be avoided, Special Condition Two (2), Section A.(2) requires the applicant to implement physical modeling of the permeable pier sand retention system in an appropriate laboratory acceptable to the Executive Director, prior to issuance of the permit.
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