Colorado

Little Cimarron River

Re-watering a key tributary of Colorado's Gunnison River

WRC took the first steps toward reconnecting prime trout habitat on a key Gunnison River tributary, the Little Cimarron, when it purchased a former dairy farm above this Colorado stream.
WRC took the first steps toward reconnecting prime trout habitat on a key Gunnison River tributary, the Little Cimarron, when it purchased a former dairy farm above this Colorado stream.
Photography | Russ Schnitzer
This stretch of the Little Cimarron often runs dry during late summer. WRC is working to reestablish perennial flows, reconnect vital fish habitat and reduce overall stream temperatures.
This stretch of the Little Cimarron often runs dry during late summer. WRC is working to reestablish perennial flows, reconnect vital fish habitat and reduce overall stream temperatures.
Photography | Russ Schnitzer
Western Rivers Conservancy has partnered with Colorado Water Trust and Colorado Open Lands and acquired a farm that will allow us to place water in-stream and ensure perennial flows where today the Little Cimarron runs dry.
Western Rivers Conservancy has partnered with Colorado Water Trust and Colorado Open Lands and acquired a farm that will allow us to place water in-stream and ensure perennial flows where today the Little Cimarron runs dry.
Photography | Dawn Reeder
The upper reaches of the Little Cimarron are teeming with naturally reproducing rainbow and brook trout. The area is cherished by fly anglers for its outstanding fishing.
The upper reaches of the Little Cimarron are teeming with naturally reproducing rainbow and brook trout. The area is cherished by fly anglers for its outstanding fishing.
Photography | Richard Durnan
The Little Cimarron flows from the Uncompahgre Wilderness and joins the main-stem Cimarron just upstream from its confluence with the Gunnison River.
The Little Cimarron flows from the Uncompahgre Wilderness and joins the main-stem Cimarron just upstream from its confluence with the Gunnison River.
Photography | Richard Durnan
Spring runoff keeps Little Cimarron flowing strong during spring and early summer.
Spring runoff keeps Little Cimarron flowing strong during spring and early summer.
Photography | Richard Durnan

The Little Cimarron River is one of the jewels of Colorado’s West Slope. It tumbles from the Uncompahgre Wilderness, bound for the Black Canyon of the Gunnison, 33 miles to the north. For the first 13 miles, the Little Cimarron has all the qualities of a Gold Medal Trout Stream, its waters cold and clear and teeming with trout. Once the river reaches the irrigation ditches of the lower valley, though, it is alternately dried up, re-watered and dried up again by irrigation diversions from mid-July to September. A great trout stream becomes little more than a rocky ditch.

This is the fate of many streams in the Rockies, and their quality can only be restored by keeping the water—the cold Rocky Mountain water—in the streambed. This in turn can only be done by buying land with senior water rights to dedicate them for in-stream use.

In 2012, Western Rivers Conservancy set out to do just this by purchasing a 214-acre farm on a stretch of the Little Cimarron that gets drained nearly or totally dry in late summer and fall. The farm possesses 5.76 cubic feet per second of senior water rights to the Little Cimarron, enough to keep the river flowing year-round if kept in stream during those drier, hotter parts of the year.

In early 2014, we conveyed these water rights to the Colorado Water Trust, which successfully pursued an irrigation plan to allow for continued agricultural operations while keeping the water in the Little Cimarron when the river needs it most. Six years later, in 2020, we sold the land to a neighboring farmer who shares WRC and CWT’s conservation vision. The new irrigation regime now functions for the benefit of both local agriculture and the Little Cimarron and its fish.

In the end, our goal was to guarantee year-round flows in the Little Cimarron all the way to the Black Canyon of the Gunnison, dramatically increasing this priority stream’s adaptability to a changing climate, while allowing native Colorado cutthroat trout to re-colonize a former part of their range. With the river now perennially unbroken, we made great strides toward accomplishing that goal.

We believe that this can be a model for other such streams, not only in Colorado but throughout the West.

Funding for the Little Cimarron River Project was made possible through generous contributions from multiple sources, including the L. P. Brown Foundation, The Conservation Alliance, ExxonMobil and with the generous support of many additional individuals, foundations and businesses.

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