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Corps begins Willamette Valley System evaluation

Published March 19, 2019
Cottage Grove Dam and Reservoir sits on the Coast Fork of the Willamette River, south of Eugene, Oregon. Cottage Grove is one 13 dams and reservoirs in the Willamette Valley System and the Corps’ continued operations and maintenance of the facility will be evaluated in the system-wide Environmental Impact Statement slated to kick-off this spring.

Cottage Grove Dam and Reservoir sits on the Coast Fork of the Willamette River, south of Eugene, Oregon. Cottage Grove is one 13 dams and reservoirs in the Willamette Valley System and the Corps’ continued operations and maintenance of the facility will be evaluated in the system-wide Environmental Impact Statement slated to kick-off this spring.

Foster Dam and Reservoir manages water coming from the South Santiam River, and is located in Sweet Home, Oregon. Foster Dam and its accompanying facilities will be part of the Willamette Valley System Environmental Impact Statement. Additional facilities included at Foster are an Adult Fish Collection Facility and a fish hatchery.

Foster Dam and Reservoir manages water coming from the South Santiam River, and is located in Sweet Home, Oregon. Foster Dam and its accompanying facilities will be part of the Willamette Valley System Environmental Impact Statement. Additional facilities included at Foster are an Adult Fish Collection Facility and a fish hatchery.

PORTLAND, Ore. — Almost three million people, or about 70 percent of Oregon’s population live in a fertile valley on the state’s western side, according to Portland State University figures. This number has doubled since 1970 – and people are still squeezing themselves into the roughly 150 mile-long valley, which is bracketed by mountain ranges and dominated by a powerful and deceptive force – the Willamette River.

This influential river has had a long history of devastating flooding, which spurred the people of Oregon and the U.S. Congress into action in the 1930’s. Congress granted the U.S. Army Corps of Engineers the authority to build a system of dams on the Willamette River’s tributaries for flood control purposes.

“This system allowed communities in the Valley to be more stable and prosperous, and in general, contributed greatly to quality of life,” said Erik Petersen, Willamette Valley operations project manager. “So much has changed since the system was built and it’s time to engage the public, to help them understand the stake they have in how we operate and maintain the project.”

“I'm looking forward to this exciting process.”

With Congressional authority and funding, the Corps went to work in the valley – as busy as beavers – completing the last dam, Blue River, in 1969. Since then, the Corps estimates that the system of 13 Willamette Valley dams have saved the region $25 billion in flood damages. However, this massive savings has been costly in other areas said Rich Piaskowski, fisheries biologist.

“The dams have blocked a substantial amount of spawning habitat for Chinook salmon and steelhead and altered hydrology and water quality in the basin,” said Piaskowski. “Without sufficient habitat to spawn and rear, fish populations have been significantly affected; although, other factors affect these populations, including land-use practices, hatcheries, and fisheries”.

In the system’s 50-year history, there have been many modifications and changes at individual dams. For instance, the Corps built and rebuilt adult fish collection facilities below several dams and it made adjustments to how the Corps operates it as a whole, like keeping downstream flow targets for fish. However, major changes in the Willamette Valley, most notably the listing of several endangered fish and the passage of time since the 1980 Environmental Impact Statement, have prompted the Corps to start a new EIS, which will address the continued operations and maintenance of the system, said Mike Turaski, Willamette Valley Systems Operations EIS project manager.

“This is an opportunity to have a conversation with the public and other resource agencies about the benefits and trade-offs of different approaches to operating and maintaining the system to meet multiple purposes and Endangered Species Act requirements,” said Turaski. “Professionally, it’s an interesting challenge and one that doesn’t come along too often, to evaluate a system that is so complex and important to the public.”

The EIS process stems from the National Environmental Policy Act and includes outreach to the public, stakeholders, government agencies, etc. Corps staff will begin providing and collecting information from the public, as part of a “scoping” process.

“As an agency, we have an obligation to ensure we have considered and taken into account public concerns,” said Suzy Hill, environmental resources specialist. “The operations management of the Willamette Valley Project has an impact on everyone that lives and works in the Willamette Basin, and it’s really important that we engage with the public, and for the public to engage with us on this project.”

 The Corps is planning on issuing a Notice of Intent to start the EIS in March and will hold public outreach meetings in May and June to give and receive public input to help the Corps inform its decision-making about the Willamette Valley System.