As glacier recedes, a chance for Alaska's biggest hydroelectric project to expand

Oct 23, 2021

The dam at Bradley Lake.
Credit Courtesy of Homer Electric Association

The Dixon Glacier, on the other side of Kachemak Bay from Fritz Creek, is rapidly receding.

That’s true for glaciers around Alaska, and the world. But what’s special about Dixon is it sits just a few miles from Bradley Lake, a source of hydropower that supplies the Railbelt with about 10 percent of its energy needs.

And as the glacier keeps retreating, the Alaska Energy Authority, which owns the project, said it can expand the project’s capacity using the water coming off the glacier. 

“If you're talking in terms of geologic time scales, it’s definitely rapidly retreating," said Bretwood Higman, a Seldovia-based geologist. "I mean, it’s something that, if you went and visited the glacier two years in a row and stood right next to it, it’d be pretty obvious it was different."

Dixon Glacier has receded enough in the last five years so that there’s now an exposed stream on state land. It’s appealing to the Alaska Energy Authority, which has been eyeing ways to expand the 120-megawatt Bradley Lake Project. 

Bradley Lake is the largest hydroelectric facility in Alaska and sends power to utilities across the Railbelt. Its power is also cheaper than other sources, at 4 cents per kilowatt hour.

Alaska Energy Authority Executive Director Curtis Thayer said diverting water from Dixon could bolster the project’s capacity by 50 percent.

"If Bradley can produce — now it produces 10 — but if it could produce 15 or 16 percent of renewable on the Railbelt, that’s huge," Thayer said.

The corporation recently wrapped up another expansion project, a three-year effort to divert runoff from Battle Creek into Bradley Lake. That project grew the production capacity of the facility by 10 percent.

Higman said, in a broad sense, energy providers can anticipate changes in the amount of water that becomes available for hydropower projects as glaciers continue to melt. And he said it could be valuable for them to anticipate how that changing landscape might affect their portfolios. 

"Bradley’s already a critical part of our power infrastructure," he said. "And it would be really nice to know how we might expect that to change as we’re doing things like developing wind that might be balanced against Bradley.”

An Alaska Energy Authority analysis from earlier this year places the Dixon project price tag at $125 million. Thayer said Alaska Energy Authority is considering a few ways to do the glacier project.

“We could divert it into Bradley Lake," Thayer said. "Or maybe even do what we call a run-of-river [hydropower], where we put a generator on the river that’s currently outflowing and create power and ship the power off and let the water still continue to go out into Kachemak Bay.”

He said it could be up to a decade before the Alaska Energy Authority brings the glacier project online. By then, there’s no telling how much more melted the Dixon Glacier will be.

This article has been updated to fix a transcription error.