California's growing demand for clean water makes potential negative water quality impacts due to erosion, leaching and transport of pathogens subjects of great concern. The influence of rangeland management on the State's water supply is of particular importance due to the threat pollutants associated with livestock production can pose to public health and to endangered species habitats. Many studies have discretely addressed these issues; however, a comprehensive, large scale water quality survey assessing potential water contamination across California while accounting for its complex topography, soil conditions, climatic zones, land cover and land use is needed to further optimize research, regulatory and management practices. Responding to this circumstance, this study revisits a previously collected water quality dataset for 16 rangeland streams from a spatial perspective, using recently available open-source geospatial data to help interpret regional trends in water quality and associated biogeochemical factors that may influence runoff.