Nearshore Biological Baseline and Fisheries Assessment at Marine Corps Base Camp Pendleton; A Regional Data Source to Supplement Site-Specific Impingement and Entrainment Assessments

One of the more challenging components of any fisheries impact assessment is collecting the appropriate level of data to accurately characterize existing baseline conditions. Site-specific data are usually preferred to capture the unique conditions present at most facilities. However, other local or regional data may act as a useful supplement to help assess the “calculation baseline” characterization of impingement and entrainment impacts. Such data are particularly useful in demonstrating how the placement or design of an intake structure (location, depth, velocity cap, etc.) may reduce impacts from the baseline condition.  Regional data also provide regulatory agencies an opportunity to compare site-specific conditions to the larger marine ecosystem.  The cooling water intake structure of the San Onofre Nuclear Generating Station (SONGS) is located offshore of Marine Corps Base Camp Pendleton (MCBCP), in southern California. Site-specific impingement and entrainment data have been collected at SONGS almost continuously since 1979. Recently, in an unrelated effort, MCBP conducted a habitat characterization and biological survey of the nearshore area along MCBCP’s 17 miles of coastline out to a distance of approximately 3 miles. The assessment included finfish, invertebrate, and kelp bed habitat surveys as well as bathymetric and sediment surveys; all within the vicinity of SONGS intake/discharge location. The nearshore area along the coast of MCBCP is a critical amphibious beach training and operational area; yet, prior to this survey, little baseline data exist for the marine resources associated with MCBCP.  This presentation will provide an overview of the findings from this survey, framed within the larger context of a regional perspective of the Southern California Bight.  A discussion of how the facilities that withdraw water from offshore intakes in the region might use such data in characterizing baseline conditions.  It is reasonable to expect, given MCBCP and SONGS proximity to one another, that these regional data are complementary and could be used to supplement site-specific data.  In this manner, the MCBCP survey provides a regional perspective for SONGS, a proposed desalination plant, and other Southern California generating stations with offshore intakes regulated by the California Regional Water Quality Control Boards.