California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project Study Areas and grid cells for assessment of groundwater resources used for public drinking-water supply

The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide, comprehensive assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is being implemented by the California State Water Resources Control Board. The USGS is the technical lead for the Priority Basin Project (PBP), one of the components of the GAMA Program. The initial focus of the GAMA Priority Basin Project in 2004 to 2012 was on assessment of water-quality in groundwater resources used for public drinking water supply (Belitz and others, 2003; 2015). Groundwater basins and sub-basins (472 in total) were prioritized based upon a number of factors (Belitz and others 2003). Two hundred [...]