LIHI Certificate #8 - Nisqually Project, Washington

March 26, 2020 - COVID-19 Update: Tacoma Power is temporarily closing all recreational facilities and wildlife lands to the public at the Nisqually Hydro Project in accordance with Governor Inslee’s Stay Home/Stay Healthy proclamation.

The Nisqually Project consists of two hydroelectric facilities: the 50 MW LaGrande facility and the 64 MW Alder facility.  Each facility includes a dam, reservoir, flowline, powerhouse, and an associated power transmission switchyard.  Both switchyards lead to a single transmission system that extends 26.2 miles to the City of Tacoma.  The Alder facility is operated in a peaking mode and LaGrande is operated as a run-of-river facility.

The Alder facility (river mile 44.2) includes a 285-foot-high concrete arch dam that impounds Alder Lake, a 7.4-mile-long storage reservoir with a maximum surface area of 3,065 acres and an operating storage capacity of 161,457 acre-feet at elevation 1,207 feet.  Adjacent to the main dam structure is a reinforced concrete spillway channel with a total discharge capacity of 80,000 cubic feet per second (cfs).  The Alder powerhouse is located at the base of the dam.  The powerhouse contains two generating units (FERC 1997).

The LaGrande facility (river mile 42.7) consists of a 192-foot-high concrete gravity dam impounding LaGrande reservoir.  The LaGrande reservoir has a surface area of 45 acres and contains 2,700 acre-feet of total storage.  The LaGrande reservoir is situated in a deep, precipitous canyon, extending a distance of 1.5 miles to the base of Alder dam.  LaGrande Dam has a large reinforced concrete spillway with an 80,000-cfs capacity.  The dam diverts flows into a 6,400-foot-long underground tunnel, which terminates at a steel penstock leading to a manifold structure serving five individual penstocks for each of five generating units in the LaGrande powerhouse.  The 1.7-mile-long LaGrande bypassed reach is situated in a deep gorge between LaGrande Dam and the LaGrande powerhouse (FERC 1997).

The project includes about 1,113 acres of land around Alder and LaGrande reservoirs for project operations and related recreation facilities.  Most of Alder Lake's shoreline is contiguous with lands of the Mt. Baker-Snoqualmie National Forest, the Washington Department of Natural Resources (WDNR), and Weyerhaeuser Timber Company.  About 177 acres of project lands are dedicated to developed recreation.  Recreational use at the project is confined to the lands and waters of Alder Lake, which includes about 28 miles of shoreline.  Tacoma operates and maintains three recreation facilities on the northern shores of Alder Lake:  Alder Lake Park, Sunny Beach Point Day-use Area, and Rocky Point Day-use Area.  The WDNR also operates and maintains a campground with a boat launch on the south shoreline of Alder Lake (FERC 1997).

The Nisqually project was relicensed in 1997 based on consultations with state and federal resource agencies and the Nisqually Tribe. These consultations resulted in new operating conditions to provide increased minimum flows in the bypassed reach and modified flows overall to provide for minimum flows in the river below the LaGrande powerhouse. There are anadromous fish (salmon species that spawn in fresh water and migrate to saltwater) in the lower portion of the LaGrande bypassed reach. There are historic barriers to fish passage in the LaGrande gorge. The Nisqually Tribe has treaty fishing rights in the Nisqually River, and operates the Clear Creek Hatchery downstream of the project area.

Project Name Nisqually
LIHI Certificate No. 8
LIHI Certificate Term April 15, 2018 - April 14, 2023
Owner City of Tacoma
State Washington
Location Located between river mile 42.5 and 44.2 on the Nisqually River in Pierce, Thurston, and Lewis Counties, Washington.
Installed Capacity Total: 114 MW LaGrande: 50 MW Alder: 64 MW
Average Annual Generation Total: 573,000 MW LaGrande: 228,000 MWh Alder: 345,000 MWh
Facility Type LaGrande: Run-of-river Alder: Peaking
FERC No. P-1862 issued 1985, expires 2025

Certification History

August 8, 2019: The decision to recertify the Nisqually Hydroelectric Project is final. No appeals were received during the appeal period which closed on May 11, 2019. The certification term for the Project is from April 15, 2018 through April 14, 2023.

April 10, 2019: The Low Impact Hydropower Institute (LIHI) preliminarily approved Low Impact Certification for the Nisqually River Hydroelectric Project, LIHI Certificate #8 for a new 5-year term.

This decision is preliminary pending the 30-day appeal window. Only those who commented on the initial application during the 60-day comment period are eligible to file an appeal. Such appeal needs to include an explanation as to how the Project does not meet the LIHI criteria. Appeal requests can be submitted by email to with “Nisqually Hydroelectric Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Ave, Suite 6, Lexington, MA 02420. All requests will be posted to the website.  The applicant will have an opportunity to respond and any response will also be posted. Requests must be received by 5 pm Eastern time on May 11, 2019.  The full application and reviewers report are available below.

December 10, 2018: The Low Impact Hydropower Institute has received a complete application for Low Impact Re-certification of the Nisqually Hydroelectric Project.  LIHI is seeking public comment on this application.  Specifically, we are interested in knowing whether you think the Project meets the LIHI Low Impact Certification Criteria, as revised in the 2nd Edition Handbook.  Please review the program and criteria in LIHI’s revised Handbook and then review the Project’s application materials below.

Comments that are directly tied to specific LIHI criteria (flows, water quality, fish passage, etc.) will be most helpful, but all comments will be considered.  Comments may be submitted to the Institute by e-mail at with “Nisqually Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Avenue, Suite 2, Lexington, MA 02420.  Comments must be received on or before 5 pm Eastern time on February 8, 2019 to be considered.  All comments will be posted to the web site and the applicant will have an opportunity to respond.  Any response will also be posted.

March 12, 2014: The City of Tacoma’s Nisqually River Hydroelectric Project has been recertified for a third five year term of low impact certification. The effective certification date is April 15, 2013 and it will expire April 15, 2018.

May 15, 2013: LIHI has received an application for recertification of the Nisqually River Hydroelectric Project. The application can be found below in the “Files” section.

August 28, 2008: The Nisqually River Hydroelectric Project has been recertified for a second five year term of low impact certification, as it continues to meet all of LIHI’s eight environmentally rigorous criteria addressing river flows, water quality, fish passage and protection, watershed health, endangered species protection, cultural resources, recreation use and access, and whether or not the dam itself was recommended for removal.

April 19, 2008: The Low Impact Hydropower Institute has received an application for recertification of the Nisqually River Hydroelectric Project, located on the Nisqually River in Washington.

September 17, 2003: The Nisqually River Hydroelectric Project has been certified as low impact for a five year term, effective April 15, 2003 and expiring April 15, 2008. It is the third hydropower facility to earn LIHI certification in Washington State, and the eighth nationwide.