Alkali Creek Reservoir Project

In 2007, Stakeholders in the Nowood Watershed Drainage approached the Wyoming Water Development Office (WWDO) about concerns of late season irrigation water shortages. In 2008, WWDO contracted Anderson Consulting Engineers (ACE) to begin a Level I Study. The purpose of the Level I Study was to evaluate and describe the Watershed and to develop a Watershed Management Plan. Through the course of the Level I Study, ACE & WWDO developed recommendations for irrigation system conservation and rehabilitation, livestock and/or wildlife upland watering opportunities, grazing management opportunities, other upland management opportunities and stream rehabilitation. The Level I Study concluded that late season water shortages exist. During this study 35 sites were identified for potential storage reservoirs. A Level II, Phase I Study was conducted by Trihydro in 2010 to expand on the Level I Study findings and identified 5 additional potential storage sites. In addition, the study estimated potential water shortages, estimated water available for storage, investigated and evaluated potential storage locations, and assessed the capability of the highest-ranked storage locations to meet water shortages and provide other Watershed benefits. During this study, Meadowlark Lake & Alkali Creek were ranked the highest for providing late season irrigation storage. In 2012, WWDO contracted Trihydro to complete a Level II, Phase II Study and further evaluate the Alkali Creek storage. The proposed Alkali Creek Reservoir is an off-channel site, filled with spring runoff from Paint Rock and Medicine Lodge Creeks through the enlargement and modification of an existing irrigation ditch. The Reservoir will have a total capacity of approximately 8,000 acre-feet, of which 6,000 acre-feet will serve as a supplemental irrigation supply for the Nowood River Watershed Improvement District, leaving a 2,000 acre-foot minimum pool for habitat, fishing and recreational use. Additionally, the Reservoir will provide some flood control and by enhancing stream flow, have the potential to positively influence downstream riparian vegetation for the benefit of fisheries and wildlife. The project has not yet begun due to the rising cost to build the reservoir.