Thursday, Oct. 11
6A — SANDAG – Toucan
“Getting to Construction: The 2012 San Diego Regional Beach Sand Project” — Shelby Tucker, SANDAG
The San Diego Association of Governments (SANDAG) approved a Coastal Regional Sediment Management (RSM) Plan in 2009 that calls for large- and small-scale nourishment over time. Regional sediment management is necessary to counteract effects of an existing coastal sediment deficit, projected sea level rise, and likely occurrence of future El Nino events in the face of increasing demand for beach recreation and need for shore protection. SANDAG is committed to large-scale nourishment in the future as an element of RSM, while local agencies implement small-scale nourishment.
As a big step toward large-scale nourishment, SANDAG plans to implement a second regional beach sand project (RBSP) within the San Diego region. This is the second in a series of efforts to nourish multiple littoral cells with sand. The 2001 RBSP was the first of its kind effort on the west coast and provided a successful opportunity to perform large-scale nourishment with minimal adverse effects. This 2012 RBSP will begin in August 2012 and place over 1.4 million cubic yards of beach quality sand on regional beaches from Oceanside to Imperial Beach. During the planning and engineering of the 2012 RBSP, SANDAG built upon the first project taking advantage of RBSP I lessons-learned. As the Project moves forward toward construction in August 2012 it has faced funding challenges, primarily dealing with rising costs that exceed funding levels. The status of the SANDAG RBSP II will be presented, including the planning, engineering, and funding components the 2012 RBSP.
“San Diego’s Regional Beach Sand Project – Environmental and Permitting Challenge” — Cindy Kinkade, AECOM
SANDAG implemented the Regional Beach Sand Project (RBSP) in 2001, in which approximately 2 million cubic yards (mcy) of sand were placed on 12 San Diego region receiver beaches between Oceanside and Imperial Beach. That project, while successfully providing additional sand to a regional littoral system that is calculated to have up to a 30-mcy deficit, did not eliminate the regional sand deficit. Now, 10 years later, RBSP II is placing up to 1.4 mcy on many of the same beaches. While postconstruction monitoring of RBSP I confirmed no long-term significant impacts to offshore resources, the environmental and planning process has been as high profile as the initial effort. An EIR/EA was prepared for the project and certified/approved in spring 2011. Over the last year, one of the primary tasks has been to obtain permits from a wide range of natural resource and coastal regulatory agencies. This presentation will take a closer look at the environmental approval process for RBSP II, as well as the permitting context for a coastal regional project such as RBSP II. Topics will include lead agency involvement, stakeholder interests, and permit coordination. It will provide an introduction to more technical discussions on the same project regarding coastal processes modeling and monitoring requirements for the project as it moves through construction.
“Shoreline Monitoring Strategy for SANDAG’s Regional Beach Sand Project II” — Greg Hearon, Coastal Frontiers Corporation
Introduction
The San Diego Association of Governments (SANDAG) plans to conduct a second Regional Beach Sand Project (RBSP II) during the summer and fall of 2012. As currently designed, the nourishment project will provide 1.4 million cubic yards (cy) of beach-quality sand to eight receiver sites. As implied by its name, the RBSP II is a follow-up effort to a similar nourishment program which provided 2.1 million cy to twelve sites in 2001 (RBSP I). The placement and subsequent dispersal of the beach nourishment material produced shoreline advances and sediment volume gains, some of which that have persisted to this day.
Shoreline Monitoring
SANDAG has sponsored a regional beach monitoring program since 1996. The program has evolved to meet changing needs and budgetary constraints, most notably the monitoring requirements associated with the RBSP I and RBSP II. The RBSP II monitoring program was developed using the lessons learned from the RBSP I monitoring effort, and includes two primary components - beach monitoring and lagoon entrance monitoring. The beach monitoring consists of beach profile surveys and oblique aerial photography, while the lagoon entrances are evaluated through oblique aerial photos, monthly inspections, and an assessment of maintenance and closure records. The beach profile surveys are conducted along 60 shore-perpendicular transects from the back beach to a location beyond the estimated depth of closure.
Anticipated Outcome
While an evaluation of the effectiveness of the RBSP II is premature, the findings of the RBSP I provide insight into the anticipated outcome of RBSP II. The beach profile survey results were used to document the evolution of the County’s beaches following the placement of the RBSP I nourishment material. The analysis focused primarily on changes in shoreline position and sediment volume.
The placement and subsequent dispersal of the RBSP I beach nourishment material produced shoreline advances and sediment volume gains, some of which that have persisted to this day. The reasons for these improvements appears to have been the RBSP I fills, and the relatively mild wave conditions that prevailed for several years following the project. The outcome of the RBSP I varied among the littoral cells, and in the case of the Oceanside Cell (where approximately 85% of the material was placed), the outcome differed by sub-reach. This was partly attributable to the individual fill characteristics and the relative locations of the placement sites. As expected fills comprised of coarser sand persisted longer than those with finer material, and larger fills tended to last longer than smaller fills. In many regions, larger areas were enhanced as closely spaced fills tended to merge.
“Environmental Monitoring for the 2012 San Diego Regional Beach Sand Project” — Lawrence Honma, Merkel & Associates, Inc.
The 2001 Regional Beach Sand Project (RBSP) was the first of its kind on the west coast and considered a pilot project. The environmental analysis suggested that no significant environmental impacts would occur, but because it was a pilot project, SANDAG took a protective approach to ensure that the project would not have any long-term significant impacts. While there was the prescriptive and required monitoring as required through various permits, there was also supplemental monitoring that SANDAG supported to assess project performance and to further support the conclusions of the environmental analysis. Results from the monitoring program indicated that no long-term significant impacts occurred, and it also suggested that several of the monitoring elements, while informational, were not critical to assess potential impacts. For RBSP II, no significant impacts are also anticipated; however, SANDAG still intends to conduct monitoring, with the primary difference being optimization of the monitoring by eliminating monitoring elements that did not meet the needs or objectives of the program or may not be required, or by combining elements to improve information return. The presentation discusses the various monitoring elements, and the general framework for the monitoring proposed for RBSP II.
*Note some abstracts have been edited for brevity; the full abstracts are available for download on the main ASBPA site.
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