Idaho Water to Benefit Fish: The Lemhi River Minimum Stream Flow and Water Supply Bank

In May 2000, irrigation water withdrawals left the lower Lemhi River dry.  Fisheries biologists found three dead Chinook salmon smolts (out-migrants) in the dry channel.  Although this was just the latest in a long history of impacts to fish and their habitat in the Lemhi Subbasin, the fact that Chinook salmon, along with Lemhi River steelhead and bull trout, were now protected by the Endangered Species Act set a series of agency actions in motion and mobilized the traditionally proactive Lemhi Valley irrigators, resulting in Idaho legislation establishing a minimum stream flow and water supply bank for the Lemhi River.  Although the water supply bank prescribed by the legislation has been modified by the agencies and irrigators, the lower river has not dried since its passage.  However, the effectiveness of the minimum stream flow is judged differently, depending upon whom you ask.  The relationship between entities in the Lemhi Valley community adds to the complexity of the water and anadromous fish conservation issues and is a dominant factor to conservation successes and continued challenges.  The application of a minimum stream flow to other watersheds in Idaho depends on the water users’ proactive and cooperative nature, the degree of a sense of community, and society’s continued acceptance of the gradual privatization of some water resources.