The South Meadow Creek Water Efficiency project was a project created by the Madison Conservation District (MCD) to evaluate aging and failing irrigation infrastructure on South Meadow Creek. Many diversions and head gates along South Meadow Creek are ineffective due to age and poor condition, which leads to difficulty for irrigators to divert their allotted water right. As a result, irrigators are often forced to alter streambed elevations and/or banks which often lead to sediment aggradation, avulsion, bed scour, bank erosion, fish blockage, and long term impacts of water quality and habitat. In addition, past land management practices have impacted the riparian corridor which has resulted in impacts toSouth Meadow Creek as well.
The South Meadow Creek Water Efficiency project analyzed specific diversion structures and developed alternatives to improve or replace irrigation infrastructure to increase irrigation efficiency and improve stream health by improving low water flows. The project goals were to:
• Identify and prioritize irrigation infrastructure sites that may be impacting the water quality and habitat of South Meadow Creek;
• Analyze cost effective modifications or replacement structures that will improve irrigation efficiency and reduce impacts to South Meadow Creek;
• Design and construct recommended replacement irrigation infrastructure; and
• Modify irrigation and land management practices as required to conserve surface water and improve riparian habitat
WET personnel worked with MCD, various agencies, and willing landowners to conduct a priority assessment of ten (10) irrigation structures. Structures were ranked based on various technical, financial, and environmental factors, with the top three (3) structures selected for detailed evaluation. WET personnel collected detailed site data, including geomorphological, riparian vegetation, and structure survey elevations, in order to develop various repair and replacement options for each site.
Results were compiled into a Planned Alternatives Analysis (PAA) report that was used as a basis for the MCD to submit a grant proposal to the Montana DNRC’s Renewable Resource Grant and Loan (RRGL) program. WET assisted with preparation of the grant proposal , and the MCD was successful in receiving a $100,000 grant to complete construction work on the three sites.