ANALYSIS OF THE EFFECTS OF BEST MANAGEMENT PRACTICES IMPLEMENTED WITHIN THE BELLE FOURCHE IRRIGATION DISTRICT

摘要

The Belle Fourche River is a natural stream that drains parts of Butte, Lawrence, and Meade Counties in South Dakota with the headwaters located in Wyoming. The river flows into the Cheyenne River in southern Meade County and ultimately to the Missouri River. The Belle Fourche River Watershed in South Dakota is approximately 2,100,000 acres (3,300 square miles) in size. The Belle Fourche River and Horse Creek, a tributary, are identified in the 1998 and 2002 South Dakota 303(d) Waterbody Lists and the 2004 and 2006 Integrated Report for Surface Water Quality Assessment as impaired because of elevated total suspended solids (TSS). A TSS Total Maximum Daily Load (TMDL) was approved by the Environmental Protection Agency in 2003 for both streams. The Belle Fourche Irrigation District (BFID), identified in the TMDL as a significant contributor to TSS loading, delivers water to 57,183 acres of farmland through its 94 miles of open main channel and 450 miles of open lateral ditches. This paper will discuss the complete water management system that was developed for the BFID. This system was designed to reduce the amount of sediment-laden flows entering the streams by increasing the overall delivery efficiency of the BFID. The components of this management system include automated check structures, head gates, and flow-measuring devices along the main canals and laterals; software to automate the water order and billing system; water master software to calculate a water mass balance needed to support water orders and compare to actual measurements; software to automate the water order and billing system; and Web-based irrigation scheduling software. Many of the automated structures are connected via radio network to the BFID headquarters, which allows personnel to monitor and control settings in real-time. Before the development of the complete water management system, the BFID operated the canals manually and performed all calculations to determine water orders, water billing, and water mass balance by hand. This was extremely laborintensive and led to inefficiencies in the transport of the water from the dam to the farmer's fields. The new water management system provides timely information to support the decision-making process. The system allows BFID personnel to assess and manage the entire system to better offset fluctuations in deliveries caused by rainfall, heat, or equipment malfunctions while substantially reducing the amount of time and effort required to perform their daily tasks.