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Introduction The central coast of California is internationally known for its incomparable shoreline. Travelers come from around the world to enjoy outstanding recreational opportun-ities including swimming, surfing, diving and kayaking; to view the spectacular coastal scenery; to observe wildlife resources such as sea otters, whales, and seabirds; and to enjoy the seemingly pristine beauty of the ocean. In 1992, public concern over the conservation of this exceptional resource led Congress to designate the Monterey Bay National Marine Sanctuary for its ecological significance and singular beauty. During the designation of the Sanctuary in 1992, eight key water quality agencies within the Sanctuary region entered into a Memorandum of Agreement (MOA) to provide an ecosystem-based water quality management process. The agreement led to the development of the Sanctuary’s Water Quality Protection Program (WQPP), a partnership of 25 federal, state and local agencies, public and private groups, dedicated to protecting and enhancing water quality in the Sanctuary and its watersheds. This partnership of MOA signatories, additional public agencies, non-governmental and private organizations are working as members of the Water Quality Protection Program Committee which oversaw the development of four action plans entitled Implementing Solutions to Urban Runoff; Regional Monitoring, Data Access, and Interagency Coordination; Marinas and Boating; and Agriculture and Rural Lands. Since the designation in 1992, runoff and spills along the MBNMS’s coastline have periodically resulted in high levels of coliform bacteria being detected in coastal waters, resulting in hundreds of beach closures or warnings annually. The Beach Closure and Microbial Contamination plan was initiated to address the issue of beach closures and will constitute the fifth action plan as part of the Water Quality Protection Program. Microbial Contamination Coliform bacteria are used as indicator organisms, and while they may not cause disease in humans, their presence tells us that water may be contaminated with organisms that do cause health impacts ranging from fever, flu-like symptoms, ear infection, respiratory illness, gastroenteritis, cryptosporidiosis, and hepatitis. Not only can humans be affected, but research into the cause of an alarming rise in mortality among the threatened southern sea otter population, shows that infectious agents have been associated with these deaths. Preliminary data suggest that many of these deaths are caused by protozoal parasites and bacteria that are spread by fecal contamination of near shore marine waters by terrestrial animals. The local economies are also affected Sources of contaminated water include runoff from urban, suburban and rural areas, an aging sewer infrastructure system pressed to meet increasing demands, contaminated flows from creeks and rivers and unidentified sources. Contributing factors that generate these sources include illicit storm drain connections, improper disposal of materials which clog pipes and cause overflows, cracked or damaged pipes, overflow of sewer systems during storm events, septic system leaching, non-point pollutant loading exposed to storm runoff, and various domestic and wildlife sources. Beach Closures and Warnings Beach closures or warnings result from a known discharge of sewage or laboratory results that indicate that the probable number of indicator organisms contained in a water sample exceed water quality standards. Since the identification of pathogens such as viruses in ocean water is difficult, time consuming, and expensive, current water quality testing methodology relies on the usage of the more readily detected and quantified coliform and fecal streptococci bacteria as indicator organisms. These organisms include total coliform, fecal coliform and enterococcus. County Health Officers can take three discrete actions including closing a beach, issuing a warning, or announcing a rain advisory based on beach water quality monitoring data, sewage spills, and storm events.
It is important to recognize that there is a fundamental difference between beach closures and beach warnings. Beach closures result from known sewage spills or repeated exceedances of standards from unknown sources, whereas beach warnings are a result of an exceedance of standards, but where there is no known source of human sewage. Domestic discharges account for a high percentage of beach closures, but closures occur less frequently than warnings. Beginning in 1999, AB411 required local health officers to conduct weekly bacterial testing between April 1 and October 31 of waters adjacent to public beaches having more than 50,000 visitors annually and are near storm drains flowing in the summer. This increased monitoring is responsible for a pronounced jump in the number of beach closures and postings between 1998 and 1999. Since this initial jump, MBNMS beaches have continued to suffer from hundreds of closures or postings annually. While California has instituted the most comprehensive water quality monitoring programs in the nation, the program is compromised because current methods of enumerating indicator bacteria are too slow to provide full protection from exposure to waterborne pathogens. The methods used to monitor and post beaches are insufficient to accurately detect contamination and warn the public accordingly. Indicator bacteria assays take 18 to 36 hours to complete and during this time beachgoers may be exposed to harmful pathogens. By the time the beach is posted, the indicator bacteria may no longer be present in the near shore waters. Thus a beach may be open when it is contaminated, and posted when it is clean. Also, this lag time makes it difficult to track sources of microbiological contamination as the source has often become dispersed over a wide area by the time investigators arrive on the scene. Beach water quality monitoring is also temporally and geographically limited. Resources preclude environmental health departments from monitoring entire stretches of beaches, and at most, these locations are monitored bi-weekly. Recently published data show that temporal changes in indicator bacteria levels in beach water occur much more rapidly. Many types of animals produce the indicator organisms, and a high percentage of beach closures and warnings are the result of unknown or diffuse sources. Data contained in the 2000 California Beach Closure Report shows statewide sources of contamination.
Domestic discharge represents an increased risk to human health and an emphasis will continue to be placed on the prevention of sewage spills through maintenance, repair, and illicit discharge detection from publicly owned sewage collection and treatment facilities. However, discharges from these facilities account for a small proportion of the total number of closures and postings. The majority of closures and postings are caused by diffuse or unknown sources, and strategies have been developed that effectively reduce the bacterial loading to these sources. A wide range of potential risks of disease are also associated with the diffuse nature of these sources, illustrating the need for strategies that further research and develop analyses that better characterize near shore pollution and its effect on human and marine health. How is the Sanctuary involved? ADDITIONAL RESOURCES:
PHOTO CREDITS: (1) Heather Cauldwell (MBNMS), (2) MBNMS Staff, (3) MBNMS Staff
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by beach closures. Tourism is the second largest industry in the Central California region after agriculture. Although definitive statistics are lacking, because much of the tourism is related to the coast, an image of closed or contaminated beaches could be a multi-million dollar threat to the local economy. 
