Project Information

Title: Eyak Lake Weir Restoration 23220612

Project Year and Number: 2023: 23220612

Other Fiscal Years and Numbers for this Project: 2024: 24220612 , 2022: 22220612

Principal Investigator (PI): Kate Morse (Copper River Watershed Project)

Managing Agency: USFS

Assisting Personnel: None

Research Location: Cordova

Restoration Category: General Restoration, Habitat Protection

Injured Resources Addressed: Cutthroat Trout, Dolly Varden, Pink Salmon, Sockeye Salmon

Abstract:

Eyak Lake is within the Exxon Valdez Oil Spill (EVOS) affected geographic area of concern, situated in the north east corner of the EVOS Area Boundary (Figure 1). It is recognized as ecologically significant by the Alaska Coastal Policy Council as an “Area Meriting Special Attention.” The streambanks at the project site and about 17 miles of upstream lake shore are EVOS acquired lands managed by the Forest Service. The habitat of Eyak Lake and its watershed are used by injured resources that include, but are not limited to, Sockeye Salmon, Cutthroat Trout, Dolly Varden, and Pink Salmon. A fifth species, Coho Salmon also uses the habitat offered by the Eyak watershed and all five of these species are targeted by subsistence, commercial and/or recreational harvesters.

Resultant of the 1964 Good Friday earthquake, the surrounding area uplifted by approximately six feet and the lake-level subsided. 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 is located at the head of the Eyak River, just upstream of the Copper River Highway (Figure 2 and 3). 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.

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 proposal 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.

This project was approved for the FY22-FY26 funding cycle.


Proposal: View (1,179 KB)

Reports:
FY23 Q1 Report: View (331 KB)
FY23 Q2 Report: View (397 KB)
FY23 Q3 Report: View (305 KB)
FY23 Q4 Report: View (389 KB)

Publications from this Project: None Available

Resolutions: