The Sacramento River Geomorphic Atlas (1896–2012) (SRGA) documents the geomorphology of the middle reach of the Sacramento River from Red Bluff to Colusa, California, shown in Figure 1. The SRGA was created using a combination of geologic maps, U.S. Geological Survey (USGS) topographic maps, U.S. Department of Agriculture (USDA) and National Agriculture Imagery Program (NAIP) imagery, light detection and ranging (LiDAR) data, other aerial imagery, historical data, and fieldwork performed by California Department of Water Resources (DWR) staff.

The data are presented in a series of maps and imagery showing Pre-Shasta Dam Meanders (Series A), Post-Shasta Dam Meanders (Series B), All Meanders (Series C), Geology (Series D), DEM/LiDAR (Series E), Bank Erosion Characterization (Series F), and Pre- and Post-Shasta Dam Bank Erosion survey sites (Series G). Channel locations are approximate and subject to cumulative errors in the original mapping, scanning, georectification, and digitization process. Depending on the series of maps, other data are also shown, such as bank protection, levees, river mile markers, meander scrolls, paleo channels, and the modern and historical meander belts. Figure 2 shows the general legend and the geologic legend for the map series. For reference, Figures 1 and 2 are also shown at the beginning of each map series. Additional data presented in the SRGA include meander avulsion identification, bank protection identification, river sinuosity, and centerline length.

Copies of this document are available from:

California Department of Water Resources Attention: Publications Office P.O. Box 942836 Sacramento, California 94236-0001 Phone: (916) 653-1097

If you need this publication in alternate form, contact the Public Affairs Office at (800) 272-8869.