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Levee Repair - Bathymetric Surveys

DWR Levee Repairs Program
Department of Water Resources

3310 El Camino Avenue,
Suite 140
Sacramento, CA 95821

Mailing Address:
P. O. Box 219000
Sacramento, CA 95821-9000

For public comments or questions e-mail:

leveerepair@water.ca.gov

Survey vessel collecting data on the Sacramento River, with sonar instrument deployed underwater (center). Bathymetric surveys were conducted in December 2007 and January 2008 along sections of levees on portions of the Sacramento, American, San Joaquin, and Calaveras Rivers. Bathymetric surveys (bathymetry) are underwater explorations conducted on a shallow draft, jet-drive boat, equipped with special multibeam sonar. This survey method provides detailed topographic data of the riverbed and riverbanks that form the base of the levee systems. Highly sensitive multibeam sonar imagery is used to reveal any underwater erosion of the riverbanks that is not clearly visible from above the river surface.

An example of the results of a Multibeam Hydrographic Survey of the Freeport area of the Sacramento River. Similar surveys have been conducted over rivers and canals along the DWR urban levee system. This data is being combined with the LiDAR data from the land-side of the levees to give scientists a comprehensive "picture" of the levee surfaces. During the recent surveys, sonar data was collected along the levees as near to the water's edge as possible. The data collected in the bathymetry surveys will supplement the above-water topographic data collected during the LiDAR surveys conducted last year. Together, these data are being used to assist in the geotechnical evaluation of the levees.

Bathymetry Fact Sheet
Survey Map