Thursday November 11, 2021
The Register-Guard —
The U.S. Army Corps of Engineers is reporting a large outmigration of juvenile salmon from Fall Creek Reservoir this year, an improvement over recent years due partly to luck and human efforts to bypass the dam that blocks migration routes.
The Corps is estimating about 50,000 juvenile Chinook salmon, a species threatened in the Willamette River system largely because dams block spawning habitat, passed Fall Creek Dam during a recent draw down meant to facilitate their migration to open ocean.
Dams play a large part in the decline of local salmon populations. With low juvenile fish passage counts at Fall Creek Dam in recent years, as few as 10,000 salmon have headed to sea.
The Corps built 13 dams on Willamette Valley rivers between 1938 and 1969 to control flooding. The dams cut salmon off from many places they once used as breeding grounds and contributed to altering rivers in a way that further reduced salmon habitat.