Tuesday April 2, 2024
KATU —
The U.S. Army Corp of Engineers says they will begin spilling more water over Columbia River Dams this year following a stay in the Columbia River Basin litigation for up to 10 years. Federal water managers will spill more water over spillways instead of through turbines during its annual “spring spill” operations at dams on the lower Snake and Columbia Rivers, officials said.
The spill operations reduce the time that juvenile salmon and steelhead move through the system of dams on their way to the Pacific Ocean. Spilling water over the spillways provides the fish with another non-turbine passage route.
“This is an important component of the agreement with Tribes, States, and other parties to implement a long-term, durable path forward,” said Tim Dykstra, USACE’s Northwestern Division Fish Policy lead. “We’ve been using spill as an important tool for fish passage since the mid-1990s to improve migratory conditions for juvenile salmon and steelhead and we will evaluate the impacts of the increased spill to inform our decisions in the future.”
Officials say the spring spill levels vary at each of the eight dams, but all projects have an upper limit that protects water quality from high levels of total dissolved gas. “Even though this additional water is valuable for fish passage, managers must reduce spill amounts to keep from exceeding 125% TDG limits that state water quality agencies set, and EPA approved in Washington, which adds more intricacy to water management in the basin,” the Corp said in a press release.