Three agencies are considering 13 options as they develop a draft environmental impact statement for operating the federal dams on the Columbia and Snake rivers.
The options range from making no changes to current operations to breaching dams on the lower Snake River.
The study also includes maintaining current barge navigation on the rivers and providing the authorized irrigation water supply for the Columbia Basin Project.
U.S. District Judge Michael Simon in 2016 ruled that federal government plans for operating facilities violated the Endangered Species Act. He ordered the U.S. Bureau of Reclamation, Army Corps of Engineers and the Bonneville Power Administration to study new alternatives to protect threatened and endangered fish.
Under the National Environmental Policy Act, the environmental impact statement must address long-term operations of the 14 federal dams in Idaho, Oregon, Washington and Montana.
The agencies held an update webinar and conference call May 30 to discuss their progress.
The agencies will evaluate the impacts of the alternatives on resources and include potential variations due to climate change, said Lydia Grimm, BPA senior policy adviser.
Among the alternatives under study is one that requires no action, meaning it would maintain current dam operations.
Another alternative would weigh the benefits and tradeoffs of removing the lower Snake River dams, Grimm said.
Environmental groups claim breaching the dams would benefit the fish, while farmers argue it would make the river unusable for transporting wheat downstream to market and transporting supplies upriver.
Navigation is an authorized purpose for the system. The study objective is to maintain navigation, not change or improve it, said Rebecca Weiss, of the corps.
The agencies will use what they learn in the studies to shape a preferred alternative, Grimm said.
“We want to make sure we’re ... getting to the right combination and have the complete answer,” she said.
They will provide another update in the fall.
Some alternatives may not create the needed benefits or could have greater impacts, so the agencies will also consider ways to mitigate them, Grimm said.
During the public scoping process, the agencies received comments on the importance of the river system for agriculture and irrigation, which is being studied, said Sonjoa Kokos, bureau ecosystems analysis program manager.
The public will have the opportunity to comment on the draft EIS in March 2020, she said.
A final EIS is slated for March 2021 with a record of decision set for September 2021.
The objectives of the EIS include improving the survival rates for protected adult and juvenile salmon, resident fish and lampreys and providing an “adequate, efficient, economical and reliable” power supply.
The agencies also want to minimize greenhouse gas emissions from power production and meet the authorized water supply obligations, Grimm said.
“There’s already authorization in the Columbia Basin Project for expanding irrigation for crops, agriculture and other purposes,” she said. “We want to make sure we’re looking at the water operations that will help fulfill that current authorized water supply.”