The US Bureau of Reclamation (USBR), US Army Corps of Engineers (USACE), Central Valley Flood Protection Board, and the Sacramento Area Flood Control Agency (SAFCA) have completed the second phase of a project to improve dam safety and reduce flood damage at the Folsom Dam, with the third phase due to start this month.
The first two phases of the Joint Federal Project (JFP) were completed by USBR on schedule and approximately $70M under budget. The work involved the excavation of approximately 2.5M cubic yards of material from the spillway and the construction of haul roads, staging and batch plants and other key infrastructure. The timely completion of Phase II was critical to ensuring a seamless transition to the Corps and establishing a strong base for continued project success.
“We are very proud of our partnership with the Corps, SAFCA and the state on this critical public safety project. Reclamation is committed to supporting completion by the Corps of their portion of the JFP in order to meet our mutual objective of protecting the citizens of Sacramento and surrounding communities and their property,” said Mike Finnegan, Area Manager for Reclamation’s Central California Area Office.
USACE will initiate Phase III, construction of the control structure, this month. The USACE Sacramento District awarded a $125.9M contract to Granite Construction Company of Watsonville, California, to build the structure, expected to take 45 months. USACE is currently finalizing design on the final two phases, which will line the spillway chute, construct a stilling basin to reduce the speed of the water and build an approach channel that will connect the auxiliary spillway to Folsom Reservoir.
“We’re excited to be starting on the remaining phases of the project,” USACE project manager Jason Magness said. “Reclamation did a great job getting the project to this point, now it’s our job to take it to completion.”
The cornerstone for more than $1B in dam safety and flood damage reduction improvements at the Folsom facility, the JFP is a new auxiliary spillway consisting of a 2400ft spillway chute, a concrete control structure with six submerged tainter gates, a 1100ft-long approach channel and other main features. Altogether, the JFP is estimated to cost $1B less and be completed faster than the three separate projects originally authorized by Congress to reduce the risk of flooding and mitigate the dam safety hydrologic risk to the Sacramento region.
“The Folsom JFP is a major component of SAFCA’s goal to provide a minimum 200-year flood protection to the region. On behalf of SAFCA, I commend our federal and state partners for working diligently and cooperatively to continue to advance this project,” said Richard Johnson, SAFCA interim executive director.
During construction of the JFP, Reclamation has continued to operate Folsom Dam and Reservoir for water supply, power generation, fish and wildlife mitigation and enhancement and other required purposes. Additionally, some one million annual visitors have experienced only minor impacts to recreation at the Folsom facility during this time.