San Joaquin District
Department of Water Resources

(559) 230-3300

Street and Mailing Address:

3374 East Shields Avenue
Fresno, CA 93726-6913

Location Map:
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Background

The Magneson Project, built in 1996, was a pond isolation project on the Merced River near Cressey, California at River Mile 30. The project area consisted of about 3,000 feet of channel and a ten acre pond. The river captured the pond in recent decades during high flow events that led to the failure of the levee. The project involved rerouting the river channel around the captured gravel mining pit.

Current Status

The berm separating the river channel from the pond was rebuilt in 1996. In early 1997, a relatively large flood event occurred that damaged a portion of the berm that had not been part of the reconstruction the year before. During the summer after the flood event, Dept. of Fish and Game and Dept. of Water Resources worked together to design and construct a permanent repair to the failed berm section. Using 6 to 8 inch cobble and 1/4 ton rocks, the berm was restored in a way that allowed flow through the porous structure during large events, but did not allow fish to travel to and from the pond. This was the River Management Section's prototype saddle structure later used in the Ratzlaff Project.

Monitoring

Although monitoring cross sections were established in 1997 and pebble counts were conducted on those sections the same year, no formal physical monitoring plan was developed or funded for this project. The Dept. of Fish and Game has monitored the berm for damage or failure after high flow events. This project has since been identified by 4-Pumps for monitoring work to be done by DWR. The work will satisfy physical evaluation and maintenance plan design requirements for these sites, and is scheduled for 2005 and 2006.

Reports

Currently, no published reports for this project exist on the Publications section of this website.

Links

More information about the 4-Pumps Agreement is available on the DWR 4-Pumps website.

Additional Photos

More photographs of this project can be found here.