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There continues to be great concern that microbial pollution by grazing livestock degrades water quality on multiple-use rangelands, threatening human and ecological health.� Given the importance of clean water on these shared landscapes and the impending changes to federal and state recreational water quality standards, there has been growing stakeholder interest in research on relationships between microbial water quality and common resource use activities on public lands. Fecal indicator bacteria (FIB), such as Escherichia coli (E. coli) and fecal coliform, are commonly used as indicators of microbial water quality and risk to human health. We will discuss several recent studies that quantified FIB concentrations in watersheds containing U.S. Forest Service public lands grazing allotments throughout the Sierra Nevada and Cascade mountain ranges in California. Results of these studies were used to characterize FIB concentrations throughout multiple-use watersheds and to assess the compatibility of current land uses with state and federal water quality standards. Examined primary land uses included livestock grazing, recreation, and rural residential areas. Sampling took place during the summer grazing-recreation season to capture the peak period of human and livestock interaction. Samples from stream sites throughout each watershed were collected regularly over the sampling periods and were processed according to established protocols. Results from these studies indicate that well-managed livestock grazing, recreation, and clean water can be compatible goals on National Forest grazing allotments.