Steps Towards Bacteria TMDL Compliance: The Proposed Inner Cabrillo Beach Natural Source Exclusion
The number one water quality beneficial use impairment along California’s coastline is for fecal indicator bacteria (FIB). Numerous total maximum daily loads (TMDLs) have been developed and implemented over the past decade, in an effort to reduce these FIB-caused water quality impairments. Unfortunately, many TMDLs have not resulted in compliance with water quality objectives, and agencies have reached a plateau of feasible source control measures. The key question many public agencies are asking is, “What Next?” This talk will present findings of a study developed to assess sources of FIB at Inner Cabrillo Beach, a low wave-energy beach located in the Port of Los Angeles (POLA) harbor complex, with the intent of pursuing a Natural Source Exclusion (NSE). Since 2000, the POLA and City of Los Angeles (City) have implemented extensive corrective measures to reduce sources of FIB in accordance with the Los Angeles Harbor Bacteria TMDL at Inner Cabrillo Beach (ICB). These measures include both institutional programs and physical improvement projects. Despite these activities, concentrations of total coliform, Escherichia coli, and enterococci along the ICB shoreline continue to exceed the TMDL criteria, and are localized to the shallow area just offshore. It is postulated that non-human fecal sources (i.e., birds) and natural ecological conditions providing non-fecal sources of FIB (i.e., eelgrass, sand, sediment) are the predominant sources of elevated levels of FIB. The Los Angeles Regional Water Quality Control Board (LA Regional Board) Basin Plan includes language providing an option to evaluate sources of FIB to determine if a water body may be eligible for a NSE. In 2011, the LA Regional Board requested POLA to develop a transparent, scientifically sound process to potentially establish NSE eligibility at ICB that did not predetermine the final NSE decision. This presentation will provide findings of the work conducted toward a NSE from 2012-2015, an adaptive strategy for the design, development and implementation of sanitary surveys utilizing molecular source tracking (MST), pathogen detection, and studies to explore the impact of non-fecal bacteria on beach conditions. Attendees will be provided with a framework useful for moving forward with a NSE, an understanding of current challenges associated with development of a NSE program, and useful information necessary to understand how a NSE may or may not be applicable to their individual situation. The audience will be engaged through interactive questions and answers to ensure that the delivery of the presentation is useful to those in attendance.
Ms. Crumpacker has been working on water quality issues in Southern California for over 10 years, focused primarily on the areas of NPDES and TMDL compliance. She is currently leading several important bacterial source investigation projects, including the Inner Cabrillo Beach NSE and City of Oceanside Loma Alta Microbial Source Tracking CBI Grant-funded study. She is passionate about improving water quality by finding stakeholder-driven solutions to complex environmental problems. Ms. Crumpacker has a bachelor's degree in biology from Truman State University, and a Master of Science degree in environmental engineering and statistics from Rice University.