The Fishery Foundation of California's Current Projects

 

 

Rooney Dam Restoration

 

Rooney Dam is a small flashboard dam located on the Cosumnes River (RM-25) owned and operated by the Omochumne-Hartnell Water District.  Prior to restoration the dam was a significant barrier to upstream migrating Chinook salmon at flows below 70 cfs.  It had a steep, four foot drop over large boulders on the downstream face of the dam.  This configuration was responsible for a significant stranding event in 2002 and caused many salmon to spawn downstream of the structure in poor habitat.  Temporary measures were taken in 2002 and 2003 to improve passage but those measures were only marginally successful.  In 2009 the FFC received a grant from the USFWS Anadromous Fish Restoration Program (AFRP) to permanently improve passage at the site.  The project improved passage by constructing a four tiered boulder weir which was designed to mimic a low gradient riffle for the salmon to pass through.   Construction commenced in September 2010 and was completed in October 2010.  Post project monitoring documented unimpeded passage at flows as low as 30 cfs last fall.  Passage at flows below this level are still problematic but are expected to improve as the weir fills with sediment over the coming years.