Tuesday, August 28, 2018

Hawley Creek fish habitat work, Lemhi Valley

Chinook salmon by the thousands used to leave the Pacific Ocean to struggle 800 miles up the Columbia, Snake, and Salmon rivers. Where the Continental Divide blocked their way, they hung a left and swam up the Lemhi River and its tributaries to spawn. Spawning fish jammed the waterways. Their thrashing and splashing kept the human residents of the valley away at night.
The Lemhi River south of Salmon, Idaho, in summer.
Europeans settlers changed the waterways of the Lemhi Valley. They rerouted tributary streams and the mainstem Lemhi to irrigate the hay fields that grow winter feed for cattle. Returning salmon found earthen dams and dry river bed blocking their way. Young fish, starting their trip to the ocean, found the same.
Angus cattle in the Lemhi Valley.
Bruce Mulkey, a rancher and chair of the Lemhi Soil Conservation District sounded the alarm in the 1980s. He urged the group (now the Lemhi Soil and Water Conservation District) to do what they could to help salmon. I wrote about ranchers saving Salmon's salmon for Hakai Magazine last fall.
The Lemhi River north of Leadore, Idaho, in fall.
Today, the LSWCD works with federal and state agencies and private landowners to return streams to their original channels and reconnect them to the mainstem Lemhi. The groups install more efficient irrigation structures and systems, which leave more water in the streams for fish.

In June, 2018, the LSWCD hosted a tour of improvements on Hawley Creek, near Leadore, Idaho. This tributary of the upper Lemhi has been returned to its original channel, after being diverted to a ditch, which left the creek bed dry for more than a century.
The LSWCD tour started where Hawley Creek enters the Lemhi Valley.
A new structure on upper Hawley Creek sends irrigation water through a pipeline to center pivot irrigation systems in the Lemhi Valley. The new pipeline loses less water during the trip than the open ditch it replaced. The pipeline delivers water directly to the center pivots, saving thousands of dollars per year formerly spent to pump water out of the ditch and onto the hay fields.
Paddle wheels power rotating drum fish screens to keep salmon out of the pipeline--and fields.
Center pivot irrigation uses less water and is far less work than flood irrigation, the former method. Flood irrigation required hours of hand work—hands with shovels in them. Ranchers also find that hay crops grow more evenly and that yields are higher with center pivots.

The pipeline and center pivot systems take less water out of the creek than the systems they replaced. This leave more water in Hawley Creek, which now adds more water to the Lemhi River.

Cumulatively, improvements on tributaries and the mainstem river have greatly increased flows in the Lemhi system. The reconnected waterways provide spawning sites for chinook salmon, steelhead, and resident trout, and nursery areas for young fish. The numbers of native fish in the Lemhi Valley are steadily increasing.
Sack lunches; come and get 'em.
Trampled grass at Homo spaiens feeding area.

The Upper Salmon Basin Watershed Program (USBWP) is installing beaver dam analogs (BDAs) in Hawley Creek, where it flows across the broad Lemhi Valley toward the mainstem river. These post and stick structures create pools that provide excellent fish habitat. Young cottonwoods trees are protected inside wire cages.
USBWP manager, Daniel Bertram, describes beaver dam analogs (BDAs) on Hawley Creek.
The last tour stop overlooked lower Hawley Creek where it has been returned to its original, winding channel. Willows trees still lined the original channel when the work started. Skilled backhoe drivers scooped up each willow, moved it out of the way, and replanted it after excavating work was done in the redesigned channel.  Light-colored gravel now fills the straight ditch, through which Hawley Creek used to flow.
Replanted willows line the original--and current--channel of lower Hawley Creek. 
Leadore rancher, Merrill Beyeler, listed five or six local families that are being supported by work on the numerous fish habitat projects in the Lemhi Valley. These families are able to stay in the Lemhi Valley and raise their children here.
Rancher Merrill Beyeler shares his local knowledge.

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