USGS scientists enumerated bacteria, including bacterial pathogens, from surface water and sand/sediment collected at an intertidal site (mudflat) near the outfall the Palo Alto Regional Water Quality Control Plant (RWQCP). This site has been monitored for metal concentrations and benthic invertebrate community for the last 30 years. Continued efforts to document changes in pollutant concentrations, forms, and types over time is critical to assess ecosystem health. Environmental water and sand samples were analyzed at U.S. Geological Survey Michigan Bacteriological Research Laboratory for enumeration of halophilic bacteria, total coliforms, Escherichia coli, and enterococci, and the enrichment and isolation of Vibrio spp.