Basins and Subbasins of the Sacramento River Hydrologic Region
To access only the basin and subbasin descriptions for this Hydrologic Region, click on the individual basin/subbasin number below. To view a map of basin and subbasin boundaries and download individual or all basin and subbasin descriptions for this Hydrologic Region, go to DWR's Integrated Water Resources Information System (IWRIS) web site. IWRIS is a GIS-based web application that allows the user to access, query, integrate, and visualize different sets of data. For the instructions on how to view groundwater basin and subbasin maps, and download basin and subbasin descriptions, click on the How do I use IWRIS? link.