Among these projects is the Dorothy Lake hydroelectric scheme. The 6.4km long glacial lake, high in the mountains east of Juneau, would generate electricity for Alaska’s capital city.

The controversy swirls around eastern brook trout, a non-native species introduced in the early 1900s, whose future could be in jeopardy if the hydro project goes ahead. Habitat biologists said drawing the lake down to provide water for the hydro plant would make it difficult at times for the fish to reach their spawning grounds in a nearby stream.

Murkowski says the habitat protection called for by the biologists was unreasonable and unnecessary.