Water
Klamath River Renewal Project
Oregon and California
Klamath River Renewal Corp. selected Kiewit Infrastructure West Co. to decommission and remove four hydroelectric dams on the Klamath River to restore river connectivity and improve fish passage.
The program included:
- Removal of four dams: J.C. Boyle, Copco No. 1, Copco No. 2 and Iron Gate
- Demolition of 100,000 cu yd of concrete
- Removal of 1.3 million cu yd of earth
- Removal of 2,000 tons of steel
- Replacement of the City of Yreka waterline crossing prior to reservoir drawdown
- Construction of two 260-foot single-span bridges to provide access across the river at two locations
The team coordinated reservoir drawdowns and flow management to align with environmental and dam safety constraints, including winter drawdown windows and staged removal sequencing to manage sediment and downstream conditions.
Completed in October 2024, the project returned 35 river miles to free-flowing conditions and reopened more than 400 miles of habitat for salmon passage as the largest dam removal effort in U.S. history.