Switzler Reservoir Water Storage Project 

Switzler Reservoir Water Storage Project

The Project

A new Columbia River off-channel storage reservoir to be constructed in Switzler Canyon (Reservoir). The Reservoir would have a peak storage capacity of approximately 44,000 acre-feet through construction of a concrete-faced rockfill dam approximately 325 feet in height and located approximately 1.1-miles upstream of the confluence of the Switzler drainage with the Columbia River. Water would be delivered to the Reservoir from the Columbia River during periods when water is available (regulatory instream flow minimums are met), which is limited during dry water years and some months during average water years. Water would be released from the Reservoir as mitigation to offset new water uses during periods when new water use is otherwise not available in the Columbia River because of low flows.

The Reservoir would occupy the majority of Switzler Canyon, located at approximately Columbia River Mile 302 within the McNary Dam pool (Lake Wallula) in Benton County. This site is situated approximately 16 miles south of Kennewick and 11 miles east of Plymouth, Washington, and Umatilla, Oregon. The area of inundation created by the Reservoir would occupy approximate 415 acres.

Vicinity map


Switzler Canyon, Benton County


Klickitat County, Benton County, and Department of Ecology’s Office of the Columbia River

New Water Supplies

This project would make available meaningful volumes of water for instream and out-of-stream uses in the McNary Dam Pool on the Columbia River, both upstream and downstream of the Reservoir.

The estimated capacity of the Reservoir would be 31,000 to 44,000 acre-feet of new water for both instream and out-of-stream uses.

The project would create new economic opportunities from mitigated (water budget neutral) water right permits on the Columbia River.

Environmental Benefits

  • One-third of water anticipated to be used for instream flow benefit in proportion to Office of the Columbia River funding

State Environmental Policy Act (SEPA) Review

Under WAC 197-11-360 and 197-11-410, the project partners initiated SEPA scoping to evaluate the environmental impacts of Switzler Reservoir Water Storage Project. Written scoping comments will be accepted through October 22, 2018. Written scoping comments on the project can be direct to:

Klickitat County Department of Natural Resources and Economic Development

Attention:  Dave McClure, Director

127 West Court Street

Goldendale, WA  98620

or via email at kcnaturalresources@klickitatcounty.org by Oct. 22, 2018.

You can help shape the EIS by participating in one of the following public meetings:

Sept. 19, 2018, 4 p.m. to 7 p.m.
Klickitat County PUD Building
1313 S. Columbus Avenue
Goldendale, WA 98620.

Sept. 20, 2018, 4 p.m. to 7 p.m.
Benton County Fairgrounds – Building 4
1500 South Oak Street
Kennewick WA 99337

The links below provide additional documentation of the SEPA process.

Determination of Significance https://fortress.wa.gov/ecy/publications/SummaryPages/1812012.html

Co-Lead MOA: https://fortress.wa.gov/ecy/publications/SummaryPages/1812013.html

SEPA Checklist https://fortress.wa.gov/ecy/publications/SummaryPages/1812014.html

Supporting Documents

Several supporting studies have been completed related to this proposal.  

Supporting Documents