Upper Hawley Creek Irrigation Improvement

Project Narrative

A fish passage barrier (headgate) was removed resulting in 1.4 miles of additional access upstream for all life stages of ESA-listed salmonids and other resident species in Hawley Creek. Through this project, 2.1 miles of an unscreened open ditch water conveyance system was converted into a screened pipeline. A new pivot irrigation system to increase in-stream flow in Hawley Creek by approximately 5.3 cfs or 3,841acre-feet/year was installed. To accomplish this objective, a point-of-use (POU) transfer was completed to realign the irrigation configuration to conform to the existing 521.7-acre water right without expansion of irrigation. As part of the new irrigation system the following were installed: by-pass weir, a new headgate, and one fish screen. The fish screen was installed by Idaho Department of Fish and Game and the flow rate of that screen is 10 cfs. As a result of the irrigation improvement, approximately 7.1 miles of stream will have improved flow as a result of decreased/eliminated water withdrawals. To compensate for the elimination of the open ditch and delivery of the BLM stockwater right, twelve livestock watering troughs were installed off stream. Continuing actions relative to this project will be the treatment for noxious weeds in the fall of 2015 and potentially subsequent years by the Lemhi County Weed Department. Idaho Department of Fish and Game will monitor the fish screen on a regular basis and conduct seasonal red counts. Other projects downstream of this project site are in various phases of planning permitting with the goal of fully reconnecting Hawley Creek. Project actions are expected to eliminate the current physical barrier at POD Hawley Creek 3, allowing passage for all life stages of ESA-listed salmonids and other resident species and will restore a more natural condition to the Hawley Creek channel at this location.