Several streams south of Petersburg are getting some major restoration work this summer. The goal is to mimic natural processes to bring back topsoil and improve fish habitat.
Two excavators were digging out part of the east fork of Ohmer Creek, a salmon stream that runs under Mitkof Highway about 21 miles south of Petersburg. They were moving huge logs, many with rootwads still attached, and placing them in the streambed.
Six decades ago, the trees along this stream were logged and many stumps removed.
“When you lose the wood out of the stream, you lose the fish habitat out of the stream,” said Heath Whitacre, a hydrologist with the U.S. Forest Service. “And the hard part to overcome is, you have a long time to wait until the trees that were logged in the flood plain come back to a size that will create more habitat in the future.”
This project aims to rebuild some of that fish habitat on an area of about 20 acres around east Ohmer Creek, along with the north and south fork of a tributary to that called Lumpy Creek.
The Forest Service has contracted with Petersburg company Rock-N-Road Construction to cut trees and truck them in from a different part of the island. In mid-July, they started using those logs to create deep pools for salmon and trout.
“We’re just basically creating a structure that will create that pool,” Whitacre said. “All that power that comes down in the water is going to basically flush out a nice deep pool.”
The repairs also stretch out into the forest, where the water flows when the streams top their banks. When it was logged, the area was also a source of gravel for crews extending the nearby Mitkof Highway. When they removed that gravel, they also took topsoil that would normally help new trees grow.
The Forest Service is partnering with the Southeast Alaska Watershed Coalition on this project. Kelsey Dean is a watershed scientist with the coalition.
“There’s a lot of areas where this happened in the 60s, and normally you would see trees be two times the size they are now, but they’re really stunted in growth because they lack that topsoil, that nutrients,” she said. “We’re also looking to restore the flood plains and recruit that soil back in by placing large wood there so that trees can grow bigger and not be this stunted.”
The watershed coalition purchased additional wood from a local company that will be dropped into the flood plain. The project also means re-engineering part of one of the creeks to divert flow into an area that’s been cut off.
The cost of the work is just over $400,000 dollars. The Forest Service is paying around $91,000 of that. The watershed coalition pays around $120,000 dollars from a compensatory mitigation fund it has. Another $155,000 comes from federal funding for projects on National Forest land, while the Alaska Sustainable Salmon Fund pays $40,000 of the project cost.
Sig Burrell owns the Petersburg contracting company Rock-N-Road. He said it’s not the first stream restoration they’ve done for the Forest Service, and they like doing the work.
“I think it will last,” Burrell said. “We did that one out on Kuiu (Island) and one on Prince of Wales (Island). Heath and these guys know what they’re doing, tell us where to dig them in and how to build these structures.”
The Forest Service did some prior restoration work at Ohmer Creek a couple decades ago, adding some rearing ponds for smaller fish. Those are showing signs of working.
The crews will be building around 15 structures in the creeks and the work should be done by early August. The Forest Service will monitor the progress one year, three years and five years after. Although the benefit for tree growth may not show up for much longer.