The massive landslide, near Sitka, Alaska, on May 13, 2013, blocked a stream which fed into Redoubt Lake and destroyed a U.S. Park Service cabin.
The stream, which is vital to the sock-eye salmon that run through the area in early July, It is now blocked by 20 feet of mud, timber and debris. However, park officials have determined that the run will not be affected and the salmon will be able to make it through the falls that were created.
“It’s not really a waterfall. It’s a low enough gradient that they should be able to get up that,” says Perry Edwards, an ecosystem biologist for the Sitka Ranger District.
“It’s really not a lot different than the outlet falls to the lake that go into salt water. So there’s a short area where they’ll really have to motor to get up through there. The fisheries biologist was confident that sockeye should easily be able to get up there, to ascend to that upper lake area and into the stream. And some of them may be able to spawn in that new lake that’s been created up there,” Edwards said.
Whether the newly formed, 55-acre lake will be permanent, is another story.
“Only time is going to tell. There’s a lot of material that came down in that slide. Old growth trees that were 3 feet in diameter, the full length crossing in there like pixie sticks. It’s really going to take some energy between that and some boulders the size of Volkswagens that came down in there. It may be there for the long haul. Or large flows may come down and carve through that. We’re really not going to know until time goes by,” Edwards said.
The blocked stream created a small lake they’ve called Little Redoubt Lake, which might serve fish and fishermen as well.
“This upper lake, if it stays there, it could become very good rearing habitat for sockeye,” Edwards said.
All good news considering the scale of the slide and the potential danger to the ecosystem!