Mashel River Restoration Project

posted in: WRIA 11 Nisqually | 0

As the largest and principal salmon producing tributary to theNisquallyRiver, theMashelRiversupports many species of salmon including endangered Chinook and steelhead. It is located inPierceCountyjust southwest of Eatonville and its sub-basin drains an area of approximately 83 square miles. The Mashel has over 20 miles of main stem river plus 67 miles of associated streams.

40yrs ago the Mashel was known as one of the premier steelhead rivers in the Pacific Northwest, but overfishing and extensive timber harvest in the 1970s and 1980s deteriorated key habitat areas and fish populations plummeted.

In 2004 SPSSEG and the Nisqually Indian Tribe placed 7 Engineered Log Jams (ELJs) in the lower 0.7 miles of the river, using a total of 40, 20-30ft long logs. These jams were monitored to determine their success in increasing the quantity and quality of gravel and pool habitat.

Following the success of the 2004 ELJs, a new restoration plan spanning 2.4 miles of river and consisting of three construction phases in 2006, 2007, and 2009 were completed. The plans included an additional 13 ELJs to create pools, collect large woody debris (LWD), reduce water velocity and increase bank stabilization. In Boxcar Canyon reach ELJs were installed to provide in-stream functions as well as re-connecting the lost floodplain and its historic side channel habitat.  The construction of the Mashel River Restoration Project was completed in October 2007 and was followed by a riparian planting, revegetating 3 acres.

The logjams won the American Council of Engineering Companies’ highest award for WA State Projects: a Gold Award in the category of “original or innovative application of new or existing techniques” with the engineering designs of Herrera Environmental Consultants.

Funding for the Mashel River Restoration Project was provided by SRFB, NFWF, FAF, and USFWS. Partners include Pierce Conservation District, Pierce County, Stream Team, Town of Eatonville, Nisqually Land Trust, Nisqually River Foundation, Nisqually Indian Tribe, USFWS, SRFB, and Fish America.