Klamath River Flows Returned To Historic Path At JC Boyle Dam Site, Fish Passage Restored

Above Photo: JC Boyle Cofferdam Breach. Credit: KRRC

Last week crews broke through the cofferdam at the JC Boyle Dam site, returning the Klamath River to its historic path and restoring fish passage in that reach of the river. JC Boyle Dam is one of the four dams slated for removal as a part of the Klamath River Dam removal project. It is the only dam to be removed in Oregon as part of the project.

Klamath River Renewal Corporation staff was joined by representatives and elders from the Klamath Tribes and Modoc Nation to view the moment the river broke through the cofferdam and joined the waters downstream.

“While there is still work to be done, today is a historic day for this reach of the Klamath River,” noted Mark Bransom, CEO of the KRRC. “It was an honor to be able to witness this reach of river coming back to life alongside area Tribes. Each milestone brings the river into a healthier state.”

JC Boyle Dam was an earth-fill dam with a concrete spillway. The earthen portion of the dam extended over the original path of the river, while the concrete portion was constructed outside the river’s path. The reservoir waters were drained back in January. Since that time, construction crews used the cofferdam, a smaller dam built behind the larger dam during the dam’s construction in the 1950’s, to route the river through the base of the spillway while the earthen portion of the dam was deconstructed.

Crews finished the removal of the earthen portion last week, allowing them to break the cofferdam on Tuesday, restoring the river in that reach to a free-flowing state that will allow volitional fish passage.

“Watching a river return to its channel, that had been buried for over 70 years, was truly inspiring,” said Dave Coffman, Klamath Restoration Director for Resource Environmental Solutions, the company overseeing the restoration of the former reservoir lands. “It has made me, and all of our folks working on this restoration project that much more excited about revitalizing this landscape.”

Crews will continue deconstructing the concrete spillway in the coming weeks. Once that is completed, they will restore the natural slope on the river’s left side and conclude construction activities related to JC Boyle Dam removal.

The removal of Copco No. 1, Iron Gate, and JC Boyle Dams are expected to be complete sometime this fall, in time for the Fall run of Chinook salmon. Copco No. 2 Dam was removed last summer. The restoration of the former reservoir footprints is currently underway and will continue for several years until vegetation is successfully established and water clarity has returned to baseline conditions.

Also see:

–CBB, Nov. 18, 2022, FERC Approves Removal Of Klamath River Dams By End Of 2024; Once Third Largest Salmon Producing River On West Coast https://columbiabasinbulletin.org/ferc-approves-removal-of-klamath-river-dams-by-end-of-2024-once-third-largest-salmon-producing-river-on-west-coast/