Multivariate Study of Fecal Indicator Bacteria Concentration in the Malibu Lagoon and Nearby Reaches in Malibu, CA

ABSTRACT\ud MULTIVARIATE STUDY OF FECAL INDICATOR BACTERIA\ud CONCENTRATION IN THE MALIBU LAGOON AND\ud NEARBY BEACHES IN MALIBU, CA\ud by\ud ?? Jeanne M. BenVau 2011\ud Master of Science in Environmental Science\ud Professional Science Master Option\ud California State University, Chico\ud Summer 2011\ud The present study investigates the influences of the natural environment on\ud detected concentrations of fecal indicator bacteria (total and fecal coliform, and Enterococcus\ud faecalis) in the Malibu lagoon (Malibu, CA), Surfrider Beach and surrounding\ud beaches. Focused study is needed to identify the underlying factors that influence pollution\ud transport. Data on the following environmental factors that influence bacterial levels\ud were gathered from various water quality agencies: wave height and period, precipitation,\ud tide height, lagoon temperature and depth, sand berm condition, and Malibu creek\ud discharge rate. Surfrider Beach and adjacent Puerco Beach were found to have significantly\ud lower average fecal indicator bacteria than Malibu Pier, also adjacent to Surfrider\ud Beach. High precipitation and elevated wave power density, associated with a storm\ud event, increased bacterial concentrations at Surfrider Beach. The combination of precipitation\ud and Malibu Creek streamflow caused an increase in fecal indicator bacteria concentrations\ud in Malibu Lagoon. During the winter, high concentrations of bacteria are caused by\ud urban runoff from high precipitation and to a smaller degree from waves that churn up\ud bacteria. During the summer, high levels of bacteria occurred during low tides, where\ud lagoon water contaminated with bacteria flowed into the nearby ocean with the falling tide.CSU, Chic