Gravel Pit Isolation

The SJRRP Predation Small Interdisciplinary Group (SIG) developed a draft Pit Prioritization Process document that outlines the general approach to prioritizing gravel pits in Reach 1. Several studies have collected data and a pit delineation report that inventories pits is in progress. MAP study 2016-8 will continue to synthesize collected data, identify data gaps and initiate a pit prioritization strategy. Future MAP studies will include collection of data gaps and working with the fisheries agencies to refine and finalize the pit prioritization.

As a result, Sycamore Island/Pit 46e was chosen a the first undertaking of its kind for the Program. Environmental review for the project was completed and construction began in 2016. Isolating the ponds helps salmon by keeping them in the river channel and away from predatory fish habitat in the pond. The project repaired a berm breach and isolated a gravel pit pond from the river channel by creating a pervious saddle and gravel road on top of the saddle and berm. In addition to habitat improvements for Chinook salmon and newly created floodplains for fish habitat on both sides of the San Joaquin River, the project increased vehicle access at the Sycamore Island Recreation Area. Construction was completed in 2018.

To learn more about the Sycamore Island/Pit 46e project, read the final summary here.

Contractors for the Department of Water Resources shore up levee improvements at Pit 46e/Sycamore Island in order to isolate former gravel mining pits that pose potential predation risks for juvenile salmon.