Andy Couch

For the past 60 years those first two words have mostly referred to salmon which fishermen have caught at the Eklutna Power Plant Tailrace, however, more than 90 years ago one of the largest abundance of salmon in Knik Arm may have been migrating up Eklutna River to spawn in the headwaters with juveniles rearing in Eklutna Lake.

That would certainly help explain the current location of the native village of Eklutna near the river’s confluence with Knik Arm. After all, what better place to locate the village than near an abundance of five species of salmon.

In 1929 a dam was first placed across the Eklutna River, stopping all upstream migration of salmon from reaching Eklutna Lake. In a short number of years, this likely greatly diminished the abundance of salmon returning to Eklutna River, however, Traditional Knowledge of Eklutna Fish Resources recorded on the Eklutna Village website mentions salmon of all species were abundant in Eklutna River before this first dam, with further mention of abundant salmon of all species into the 1950s. The water volume flowing through Eklutna River, at that time, is thought to be similar to what currently flows down Eagle River, closer to Anchorage now.

On July 1, 1955, the new Eklutna Power Plant with a 4.5-mile tunnel drawing water from the lake went online. This project effectively diverted all lake outflow water away from Eklutna River. The river channel directly below the upper dam at the outlet of Eklutna Lake no longer has any water flow except during extremely rare high water events. It has been estimated the current water volume of Eklutna River where it passes under the Glenn Highway is now 80% water from Thunderbird Creek with just a little water coming down the Eklutna River channel tributaries upstream from Thunderbird Creek. While annual salmon migrations continue into what is left of Eklutna River, with loss of the water, salmon numbers have greatly diminished.

More recent developmentsDuring the 1990s the Federal Eklutna Hydroelectric Project was purchased by Southcentral Alaska utilities with an agreement that mitigation would occur for affected fish and wildlife. The mitigation steps were postponed in starting for 25 years to ensure profitability for the utilities.

The Conservation Fund spearheaded an effort to remove the lower dam on Eklutna River that took four years (2014–2018) and $7.5 million to accomplish. With removal of the dam salmon could once again migrate all the way to the dam blocking the river outlet from Eklutna Lake if and when stream flow is restored below the dam. Many Alaskans may have seen several new articles about the dam removal, and wonder what has happened since.

Ron Benkert, habitat supervisor with the Alaska Department of Fish and Game (ADF&G), in conjunction with the Native Village of Eklutna has been documenting current instream flow conditions and documenting abundance of fish species present. During 2020 the first few juvenile coho salmon were documented upstream of the old dam site.

Next up is a study planning process to identify how much water may be needed to adequately mitigate for adult salmon and juvenile salmon migration needs and juvenile rearing habitat needs — the results of which will be submitted to Gov. Mike Dunleavy. Benkert was hopeful that instream flow studies with actual water flows immediately below the Eklutna Lake dam could start by April 2020.

ConsiderationsAbout 10% of current water drawn from Eklutna Lake is used for drinking and waste water needs in Anchorage. The working group plans to continue providing for these needs.

Approximately 90% of Eklutna Lake water draw has been used for electricity generation at Eklutna Power Plant. Adequate water to mitigate for fish migrations and habitat needs will need to be provided. Water draws for electricity generation may need to be dramatically altered to provide adequate instream flows during winter months. Brad Meiklejohn with the Conservation Fund identified possible minimum instream flow levels of 50 cubic-feet per second during winter and spring months and 100 cubic-feet in summer and fall months. The plan is to continue outflow and some level of power generation, however, adequate instream flow during winter and spring months may necessitate changing power draw timings.

Sport fisheries for stocked king salmon and coho salmon currently occur at the Eklutna Power Plant tailrace, and ADF&G hopes to continue these popular fisheries, so adequate water through the power plant tailrace will need to be maintained in the late May through September timeframe. Benkert felt that some of the salmon smolt released at the Tailrace may choose to migrate up Eklutna River when instream flows are re-established from Eklutna Lake. This may serve to help jump-start additional abundances of salmon into the Eklutna River and Lake. The opposite flow of salmon would also likely occur in the future — where sockeye smolt after rearing and migrating from the lake would likely return as adults to outflows of Eklutna Lake water in Eklutna River and also at the Eklutna Power Plant tailrace.

I talked with three individuals in developing this story: Ron Benkert, Brad Meiklejohn, and Austin Williams with Trout Unlimited, and all three agree that the potential for seeing the greatest amount of salmon production from this system was only realized with salmon migration past the Eklutna Lake dam and into the lake where sockeye in particular could make use of the lake’s rearing habitat, before migrating to the ocean and back. Each one of these individuals also mentioned important tributary stream habitat for salmon upstream of the lake.

What size future salmon returns might occur from Eklutna Lake/River system?Future returns would likely have to build up over time, but for comparison there are four lake systems with ADF&G sockeye salmon escapement goals in Northern Cook Inlet: Judd, Larson, Chelatna, and Big Lake (Fish Creek). In terms of surface acres Eklutna Lake has more than any of the four, although there are additional lakes in the Big Lake / Fish Creek system. To me, it therefore seems, with the right salmon mitigation efforts, Eklutna Lake/River system has the potential to once again produce salmon returns on par with the heavyweight systems of Northern Cook Inlet. I fully support efforts to rewater the Eklutna River and bring Eklutna salmon stocks back to their former abundance levels.

Andy Couch is a member of the Matanuska Susitna Borough Fish & Wildlife Commission and the Matanuska Valley Fish and Game Advisory Committee, however, opinions he expressed in this article are his own, and have not been considered by these groups.

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