WESPEN Online Order Form print this page
US Fish & Wildlife Service FieldNotes

CONSERVATION PARTNERSHIPS:Fish and Flood-Friendly Culverts: Spotlight on Tyonek, Alaska!

Region 7, June 1, 2013
Indian Creek flows through the Native Village of Tyonek, ~40 air miles from Anchorage, Alaska.
Indian Creek flows through the Native Village of Tyonek, ~40 air miles from Anchorage, Alaska. - Photo Credit: n/a
The road washed out with spring flows in 2012 and was fitted with a 2 ft temporary culvert.
The road washed out with spring flows in 2012 and was fitted with a 2 ft temporary culvert. - Photo Credit: n/a
A new 8ft diameter fish and flood friendly culvert, designed by the Service's Alaska fish passage engineer, was installed in October 2012.
A new 8ft diameter fish and flood friendly culvert, designed by the Service's Alaska fish passage engineer, was installed in October 2012. - Photo Credit: n/a
The streambank downstream of the new, bigger culvert was revegetated with native willow clippings in June of 2013.
The streambank downstream of the new, bigger culvert was revegetated with native willow clippings in June of 2013. - Photo Credit: n/a

The Native Village of Tyonek (NVT), with a population of less than 200, is located 40 air miles from Anchorage, on the western shore of Cook Inlet.

 Indian Creek flows through Tyonek into Cook Inlet and supports important subsistence fisheries for salmon and rainbow trout. During the heavy spring flows of 2012, the creek washed out a 4ft diameter road culvert. The road was rebuilt and fitted with a temporary 2ft culvert.

Washouts and chronic road maintenance where roads and streams converge are a common symptom of too-small culverts: there is just too much water for the culvert to handle and the water has nowhere else to go but over (or through) the road. These too-small culverts also cause big problems for migrating fish by constricting the stream flow and causing high velocity conditions that juvenile fish can’t move beyond. These conditions often also result in a growing “perch” at the culvert's outlet that fish can’t jump into.

In October 2012, Indian Creek was fitted with a much larger (8ft diameter) fish- and flood-friendly culvert designed by the U.S. Fish and Wildlife Service’s Alaska fish passage engineer. Habitat through fish-friendly culverts mimics the natural stream channel, allowing fish to pass through similar conditions under the road that they’d encounter elsewhere in the stream. Culverts designed to let juvenile salmon move freely among important rearing habitats not only boost fish production, but are also immensely valuable from a road maintenance and public safety perspective...they keep fish habitat and communities connected, no matter what the weather!

“For the first time in a long time, this creek crossing did not wash out during the spring melt,” said Christy Cincotta, Executive Director of the Tyonek Tribal Conservation District (TTCD) in 2013. “NVT machinery operators did a great job and this project provided a great opportunity for local operators to learn the techniques involved with installing a fish-friendly culvert.”

Following the culvert upgrade, fish habitat was further improved along the Creek in early June 2013 by layering 100 feet of live willow clippings just downstream of road-stream crossing. Vegetated streambanks provide habitat for fish and wildlife, as well as bank protection and erosion control.

TTCD hopes to continue to work with NVT and other partners on future culvert installation projects. With this kind of example, interest in fixing more culverts in and around tribal lands has increased.

As typical with habitat restoration projects, a variety of partners worked together to make it happen—this particular fish passage project is an outgrowth of a strategic planning project completed by Tyonek Tribal Conservation District (TTCD) and funded by the U.S. Fish and Wildlife Service’s Alaska Coastal Program. The plan identified a wide range of potential habitat improvements and helped TTCD develop a partnership with the Service’s Fish Passage Program and the Alaska Department of Fish and Game to remove fish passage barriers. The strategic planning process also resulted in TTCD becoming involved with both the Kenai Peninsula and Mat-Su Basin Fish Habitat Partnerships. This project is a good example of the Alaska Region’s Habitat Conservation Partnership Programs complimenting each other to achieve on-the-ground conservation benefiting fish and wildlife and the needs of our partners.

Contact Info: Katrina Mueller, 907-786-3637, katrina_mueller@fws.gov