Dam projects improve migration of salmon

Improvements at all eight federal Snake and lower Columbia River dams boosted the safe migration of juvenile salmon and steelhead last year, a federal study says.

Army Corps of Engineers officials said completion of improvements such as spillway weirs, also called fish slides, help speed young fish downstream past dams by keeping them near the water surface, where they naturally migrate.

For example, tests at Little Goose Dam on the Snake River found 99.4 percent of yearling chinook, 99.8 percent of steelhead and 95.2 percent of sub-yearling chinook passed the dam safely.

The assessment report says in-river survival of juvenile Snake River steelhead migrating to the ocean in 2009 reached its highest level in 12 years, a sign the fish are benefiting from improved surface passage.

The report describes the second year of progress by the corps, U.S. Bureau of Reclamation and Bonneville Power Administration in implementing NOAA-Fisheries' biological opinion for the federal Columbia River power system.

The so-called bi-op outlines protections for fish affected by the federal dams.

According to the assessment, the agencies in 2009 reopened nearly 265 miles of spawning and other salmon and steelhead habitat that had been blocked by impassible culverts, diversions or other obstacles.

Since 2005, the agencies have restored access to a total of 845 miles of habitat.

"Fish are returning in numbers we haven't seen in decades and to places they haven't been for decades," said Lorri Bodi of the Bonneville Power Administration.