March 3, 2023
U.S. Army Corps of Engineers Recommends Safe Flood Storage at Seattle’s Skagit Dams
Corps Recommendation Backs Unified Skagit Flood Request
Seattle City Light is currently seeking a new 50-year federal license for its Skagit Hydroelectric Project from the Federal Energy Regulatory Commission (FERC).
Over the past year, Skagit County, the cities of Burlington, Mount Vernon, Anacortes, Sedro-Woolley and La Conner, Skagit Public Utility District No. 1, the Skagit Dike District Partnership and the Skagit Drainage/Irrigation Districts Consortium (the “Skagit Community”) have all formally requested that Seattle provide a safe level of flood storage at Ross Dam, the uppermost of the three dams at Seattle’s Skagit Hydroelectric Project. The Upper Skagit Indian Tribe has also expressed support with FERC for the unified Skagit flood request.
On March 24, 2022, Skagit County and the Skagit Dike Partnership filed a request with FERC, asking that Seattle be required to draw down Ross Reservoir to provide 200,000 acre/feet of flood storage by November 1 of each year. The current license requires only 120,000 acre/feet of Ross drawdown by December 1, a dangerous situation given that many large Skagit floods occur well before December 1.
While Ross is usually drawn down to augment stream flows for fish in the fall anyway, a safe level of flood storage drawdown is not a mandatory part of Seattle’s current FERC license. As such, safe flood storage and the needs of salmon are not only compatible, but mutually reinforcing.
Flood storage at Ross is the most important flood risk reduction measure in the Skagit Valley, and flood control is the Skagit Project’s first operational purpose. Without flood storage, the Army Corps of Engineers reports the November 2021 Skagit flood would have been 8’ higher at Mount Vernon, creating catastrophic flooding in Burlington, Mount Vernon, and throughout the Skagit Valley, potentially causing loss of life and billions of dollars in damages.
In Seattle’s Draft License Application, filed with FERC on November 30, 2022, Seattle rejected the Skagit Community’s flood request without comment or analysis.
On February 6, 2023, Skagit County and the Skagit Dike Partnership filed a comment letter on Seattle’s Draft License Application with FERC, again asking for 200,000 acre/feet of Ross flood storage drawdown by November 1, demonstrating that the requested additional flood storage will have little to no impact on either salmon or Seattle’s financial interest in power production.
On February 23, 2023, the U.S. Army of Engineers filed a letter with FERC recommending that Seattle’s new federal license require 200,000 acre/feet of flood storage by November 1 of each year.
“On behalf of the Skagit County Board of Commissioners, I’d like to express our community’s gratitude to the U.S. Army Corps of Engineers for their expertise, wisdom, and sound judgment,” said Skagit County Commissioner Peter Browning. “Safe flood storage at Ross is one of our community’s top priorities.”