Water Measurement and Management Initiatives in the Pioneer Irrigation Ditch

The Pioneer Irrigation Ditch diverts water from the North Fork of the Republican River in northeastern Colorado near the town of Laird. The project was originally constructed in the 1890's and features 15 miles (24 km) of main canal which crosses the state line into Nebraska before terminating near the town of Haigler. With typical diversion rates ranging from 11 to 37 ft³/sec (0.31 to 1.0 m³/sec), the ditch provides water for approximately 2,600 irrigated acres (1100 ha) and 22 landowners in Yuma County, Colorado and Dundy County, Nebraska. Flow measurement for management and accounting purposes has historically been limited to diversion measurements near the project headworks, interstate transfer measurements in the main canal at the state line, and return flow measurements at the tail end of the project. These measurements are all accomplished using Parshall flumes. In 2003, extended drought conditions and recurring water shortages prompted the district to request assistance from the Bureau of Reclamation. Specifically, the district sought help with implementing water measurement and management practices throughout the system that would enhance water conservation and the equitable distribution of limited water supplies among the project recipients. A variety of low-cost flow-measurement options to quantify turnout deliveries were suggested to and implemented by the district over the following two years. These included simple weirs, submerged orifices, elbow meters, long-throated flumes, propeller meters, and home-made venturi meters. This effort resulted in decreased waste within the system and a more equitable distribution of water throughout the system—particularly to the users at the tail-end of the system who had typically borne the brunt of any water shortages in the system.