Lower Mokelumne River Spawning and Rearing Habitat Improvement Project

The project is a long-term habitat restoration project to support fish populations on the Lower Mokelumne River, a tributary to the Sacramento-San Joaquin River Delta. This reach of the river is known to support fall-run Chinook salmon and steelhead spawning and rearing.

Availability of spawning gravel in this section of the Mokelumne River is deficient because historic mining operations removed hundreds of thousands of tons of gravel annually and upstream dams limit gravel transport to the area. Juvenile salmon rearing habitat is also limited because of channel incision.

The project will result in the placement of 2,500 to 5,000 cubic yards of spawning gravel annually for 3 years at two sites. In addition, there will be 500 to 1,000 cubic yards supplemented annually, as part of the long-term restoration program implemented since 2001. Rearing habitat would be improved by the creation of small (less than an acre) floodplains that will seasonally inundate EBMUD’s Mokelumne River Day Use Area. Gravel would be sourced from local quarries, quarries in neighboring watersheds or existing cobble piles on EBMUD lands, based on availability and permitting.

Workplan and schedule

Work will be conducted each year over a period of 1 week within the months of August and September. Exact dates of work will be dependent on operations and releases from Camanche Dam.


Ed Rible, Fisheries & Wildlife Biologist II
EBMUD Fisheries and Wildlife
Phone: 209-263-6370
Email: Ed Rible

Published studies and other resources

EBMUD has assessed the potentially significant environmental impacts resulting from the construction of this project and has determined that a Mitigated Negative Declaration (MND) is the appropriate level of California Environmental Quality Act review. EBMUD developed an action plan to reduce potential impacts to a less than significant level. The mitigations are summarized within the MND. The EBMUD Board of Directors adopted MND at its August 12, 2014 meeting.

Document Type Size
Initial Study and Mitigated Negative Declaration PDF 2.6 MB