Open-File Report 2011–1091
Each year, over 550 million people visit California's public beaches. To protect beach-goers from exposure to waterborne disease, California state law requires water-quality monitoring for fecal indicator bacteria (FIB), such as enterococci and Escherichia coli (E. coli), at beaches having more than 50,000 yearly visitors. FIB are used to assess the microbiological quality of water because, although not typically disease causing, they are correlated with the occurrence of certain waterborne diseases. Tests show that FIB concentrations occasionally exceed U.S. Environmental Protection Agency (USEPA) public health standards for recreational water in Malibu Lagoon and at several Malibu beaches (Regional Water Quality Control Board, 2009).
Scientists from the U.S. Geological Survey's (USGS) California Water Science Center are doing a study to identify the distribution and sources of FIB in coastal Malibu waters (fig. 1). The study methods were similar to those used in a study of FIB contamination on beaches in the Santa Barbara, California, area (Izbicki and others, 2009). This report describes the study approach and presents preliminary results used to evaluate the distribution and source of FIB in the Malibu area. Results of this study will help decision-makers address human health issues associated with FIB contamination in Malibu, and the methods used in this study can be used in other coastal areas affected by FIB contamination.
First posted May 13, 2011
Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.
Izbicki, John, 2011, Distribution of Fecal Indicator Bacteria along the Malibu, California, Coastline: U.S. Geological Survey Open-File Report 2011-1091. 8 p.
Potential Sources of FIB
Overview of Sample Collection and FIB Concentrations)
Seasonal and Tidal Influences on FIB Concentrations
Identifying Wastewater and Groundwater Discharge
Identifying Sources of Fecal Indicator Bacteria (FIB)