California hydrological zone maps

California Hydrologic Regions

Hydrologic regions are a part of a larger hierarchical system of classification adopted by the United States Geological Survey. In this method, hydrologic regions are geographic areas that contain the drainage area of a major river or series of rivers. This information is traditionally mapped upon various types of boundaries including at a national, state, and county level. However, to an individual trying to understand this data with relation to their immediate community, it is often hard to contextualize such large geographic areas. Therefore, we have attempted to map the hydrologic regions of California by ZCTA* boundaries.

Using the Map Data
This map is available for free for non-profit use, if cited properly. Required minimum citation includes the source name, map name, year published, and links back to project page (or displays url). Example: "Source: UC Berkeley CoolClimate Network Hydrologic Regions Map (2012)"

File Download
Download Microsoft Excel Spreadsheet (.xls) Version

Download Tagged Image File Format (.tif) Version