Gunnison River

The Gunnison River is located in western Colorado and it is one of the largest tributaries of the Colorado river. The 180 mile long river flows east to west and has a drainage area of 7,923 square miles according to the USGS. The drainage basin of the Gunnison River collects water from different habitats, such as forests and alpine meadows, located the along Continental Divide. As the river flows westward it carves through the San Juan Mountains. The Gunnison River flows into the Colorado River at Grand Junction. In addition, the Gunnison River Basin is popular for recreational activities such as fishing, rafting, boating, camping, hiking, and rock climbing.
Contamination of the Gunnison River with selenium and mercury results from irrigation of high-selenium soils derived from the Mancos Shale and mineral mining. The region surround the Gunnison River is also part of the Colorado Mineral Belt. Contamination of the Gunnison River with selenium and mercury is a conservation concern for the bonytail chub, Colorado pikeminnow, humpback chub, and the razorback sucker whose critical habitat includes the lower Gunnison River.

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