2019-2021 Spill Agreement for Dams Was Successful, Agencies and Tribes Say
- January 04, 2021
- John Harrison
The second year of an innovative, two year agreement regarding spilling water at lower Snake and Columbia river dams was a success in terms of fish passage and downstream survival, and also hydropower sales, representatives of the agencies and tribes that negotiated the agreement told the Council at its December meeting. Whether the flexible spill operations improved fish survival in terms of producing more adult fish won’t be known for at least two years, when fish begin returning from the ocean.
The 2019-2021 Flexible Spill Agreement called for increased spill to aid juvenile passage when power prices are low and reduced spill to allow additional power generation when prices are higher. In general, spill was decreased for 16 hours of the day and increased for eight hours. The amount of increase and decrease depended on river conditions. In 2020, an average water year in the Columbia River system, the U.S. Army Corps of Engineers, which operates the dams, managed the spills under terms of the agreement to dissolved gas limits in the dam tailraces, with only a few exceptions.
Because of the innovative spill, juvenile fish passed the dams faster than usual, fish survival through the system was higher than usual, fewer fish were transported downriver in barges, and fewer fish passed the dams through the turbine pits, thus decreasing the “powerhouse encounter probability,” an important measure of fish survival. The turbulent water and high pressure of the turbine pits can injure or kill the tiny fish. In terms of hydropower, the flexible spill regime increased income for Bonneville by about $4.7 million. One issue the Corps will study further is whether the spill increases caused any damage in the tailrace area below each dam.
Ben Zelinsky, senior policy advisor, Bonneville Power Administration, said the operations met goals in the agreement for fish benefits, power benefits, and operational feasibility. Implementation of the agreement also avoided litigation while federal agencies completed an environmental impact statement and biological opinion on Columbia and Snake river dam operations, a stipulation of the agreement.
The agreement was signed in December 2018 by representatives of the states of Oregon and Washington, the Nez Perce Tribe, Bonneville, the U.S. Army Corps of Engineers, and the Bureau of Reclamation. The agreement and the specific commitment to the flexible spill operation included in the agreement ended in 2020. But, the preferred alternative in the 2020 Columbia River System environmental impact statement and the 2020 NOAA Fisheries biological opinion on river operations to protect ESA-listed salmon and steelhead included the flex spill operation as a baseline operation in 2021, to be adaptively managed in future years.
While no lawsuits challenging river operations were filed during the two-years of the agreement, a coalition of environmental and fishing groups, the State of Oregon, the Spokane Tribe, and the Coeur d’Alene Tribe all sent notices to the federal agencies announcing their intent to file litigation over the 2020 Biological Opinion and Environmental Impact Statement – which include the flexible-spill operations. The environmental and fishing groups and the Spokane and Coeur d’Alene tribes subsequently filed petitions for review with the Ninth Circuit reserving their challenges against the Bonneville Power Administration for judicial review. No litigation has yet been filed in federal district court.
In response to a question about why Oregon sent the 60-day notice letter, despite being a party to the agreement, Ed Bowles of the Oregon Department of Fish and Wildlife said the agreement was considered interim while federal agencies worked on the EIS and new biological opinion, and that, in the state’s view, the resulting documents cannot satisfy the Council’s objectives for fish survival. He said Oregon would continue to work with others to address its concerns with the EIS and the biological opinion, including in a four-state collaborative process convened by the Governors to improve salmon survival.
Guy Norman, a Washington member of the Council, called the spill agreement “groundbreaking in terms of collaboration, working through technical challenges and policy issues.” Ted Ferrioli, an Oregon member of the Council, praised the collaborative spirit of the agreement, which brought together groups and agencies that have opposed each other in past lawsuits. “If I were looking for how adaptive management is supposed to work in something as complicated as the Columbia River system, this would be a great presentation to make, showing how adaptive management can work,” he said.