Project Description
This project aims to improve fish and other aquatic organism passage into the Eyak Lake basin by replacing a weir located at the outlet of the lake. Partners include the Copper River Watershed Project, the Alaska Department of Transportation, the U.S. Forest Service, and U.S. Fish and Wildlife Service.
Eyak Lake is within the Exxon Valdez Oil Spill (EVOS) affected geographic area of concern, situated in the northeast corner of the EVOS Area Boundary. Eyak Lake is recognized as ecologically significant by the Alaska Coastal Policy Council as an “Area Meriting Special Attention.” The habitat of Eyak Lake and its watershed are used by injured resources that include, but are not limited to, Sockeye Salmon (Oncorhynchus nerka), Cutthroat Trout (Oncorhynchus clarkii clade), Dolly Varden (Salvelinus malma), and Pink Salmon (Oncorhynchus gorbuscha). A fifth species, Coho Salmon (Oncorhynchus kisutch) also uses the habitat offered by the Eyak watershed and all five of these species are targeted by subsistence, commercial and/or recreational harvesters.
The weir is located at the head of the Eyak River, just upstream of the Copper River Highway. The weir impedes upstream passage of juvenile salmon and other aquatic organisms and has structural concerns with the potential for further adverse effects on the ecosystem if not addressed. The streambanks at the weir, and about 17 miles of upstream lake shore, are EVOS acquired lands managed by the U.S. Forest Service.
The weir was installed to mitigate the effects of the 1964 Good Friday earthquake. The surrounding area uplifted by approximately six feet and the lake-level subsided during the earthquake, leaving behind mudflats. In 1972, a sheet pile weir was installed at the outlet of Eyak Lake to re-establish the water surface to pre-earthquake levels. The weir was originally designed to provide passage to small, motorized vessels. In addition, anglers used the weir platform for fishing access. Currently, the weir is largely impassible to vessels and unsafe for fishing access.
Since the weir was installed, damage to the integrity of the structure has occurred from environmental elements including freeze-thaw events. Additionally, there have been advances in understanding the importance of restoring ecological connectivity and aquatic restoration practices have evolved since the weir was installed. This project seeks to restore upstream aquatic organism passage into the lake, and to preserve and improve the productivity of the salmon and Cutthroat Trout spawning and rearing that the Eyak Lake watershed supports.
Restoration Land Ownership
Other Federal; State; Tribal; US Forest Service
Parties Implementing Restoration
Alaska Department of Transportation; Copper River Watershed Project
DOI Project Representatives
Fish and Wildlife Service