Flows will change in the American River this week while federal officials install a fish weir below Nimbus Dam to prepare for the fall salmon migration.

Overnight Wednesday, the U.S. Bureau of Reclamation planned to drop American River flows from 2,500 cubic feet per second to 1,000, then return to 2,500 during the day. This is planned so crews can do maintenance on the weir structure.

Then on Friday starting at 1 a.m., flows will be dropped again to 1,000 cfs to install the weir, and increased back to 2,500 cfs by afternoon.

These actions will change the river elevation by about 14 inches, as measured in Fair Oaks. People recreating and traveling along the river are advised to use caution near the water’s edge.

The weir is installed across the river annually to guide spawning fall-run Chinoook salmon into the Nimbus Hatchery fish ladder.