GRANTS PASS, Ore. (AP) – With water scarce in Northern California’s Klamath Basin, a federal agency is again releasing cool clean water into the Klamath River to prevent a repeat of the 2002 fish kill that left tens of thousands of adult salmon dead.

The U.S. Bureau of Reclamation said releases started Friday from Lewiston Dam on the Trinity River, the Klamath’s primary tributary, and would continue into late September. Similar releases were done the last three years. They come from water that is shared with farms in the Central Valley.

The releases were sought by the Hoopa Valley and Yurok tribes and Humboldt County to prevent an outbreak of a gill-rotting disease known as Ich, which spreads in low, warm water. The cooler and rising water spurs salmon to swim upstream to spawn.