Jefferson River, MT

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The Jefferson River project, located in southwestern Montana, was the first Home Rivers project established west of the Mississippi River and was initiated in 2001.  Although the Jefferson is relatively intact, it suffers largely from a single problem, insufficient water.  The recent 8-year drought and past aggressive water appropriations for agriculture have severely reduced river flows.  This has contributed substantially to the drop in the resident brown and rainbow trout populations, which have declined by 75% since 1985.  In the 1980’s, the Jefferson supported wild populations of trout that numbered more than 700 per mile.  Today populations have fallen below 200 per mile in some reaches.

Trout Unlimited is working with NRCS, the Jefferson River Watershed Council (JRWC) and the state of Montana to restore this storied river to its former condition.  The goal of this project is to improve the coldwater fishery to its previous healthy state by improving streamflows; increasing tributary recruitment of young salmonids through stream restoration work; and restoring the hydrograph to a more natural flow regime.  Today the Jefferson River provides a real opportunity to demonstrate collaborative problem resolution in the water-poor West.

Improving stream flows is the primary objective of the project.  During average flow years trout numbers remain steady, but when drought and upstream demand reduces flows, impacted reaches were completely dewatered.  The JRWC, with TU support, has initiated a voluntary Drought Management Plan to maintain minimum flows of 50 cfs., which while less than ideal allows fish passage from pool to pool in the mainstem.  At several agreed upon “trigger points” irrigators and anglers take various levels of conservation action including reducing irrigation diversion and closing the river to angling.

NRCS has become a partner and has committed $400,000 for an engineering study of the 58 miles of irrigation canals, a groundwater/surface water interaction study and irrigation demonstration projects.  During the late winter and early spring of 2008, two major irrigation control structures along the 28 mile Parrot Ditch were completely replaced and a third structure was equipped with steel control gates.  This work was identified in the engineering work, will allow refined management of water within the ditch system and will directly save about 6 cfs.

The Jefferson River has only 12 tributaries along its 80 mile course.  Successful spawning occurs in very few of these tributaries.  TU and Montana Fish, Wildlife and Parks are working to increase recruitment through tributary restoration.  To date, Willow Springs has again been improved since the original work (2005), Parson’s Slough and the first section of Fish Creek were restored in 2007, with a second section of Fish Creek re-worked in 2008.  Several more restoration projects are in various stages of development.

The restoration efforts are clearly showing positive results.  Since 2003, rainbow trout numbers have been steadily increasing in the Waterloo section of the Jefferson River.  This mainstem reach includes two of the restored tributaries and was accomplished during the recent drought (2000 through 2007).