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Backgrouad The District owns and operates Empire Reservoir located west of Fort Morgan in Weld and Morgan Counties, between I-76 on the south and US Highway 34 on the north. It provides irrigation water to a 19,177-acre service area in Morgan County, located between the reservoir and the City of Fort Morgan. The District levies an annual assessment per acre based on benefits received. In addition to the Reservoir, the District owns and operates the diversion structure/headgate on the South Platte River for the Empire Intake Canal as well as a reservoir outlet canal. Annual District headgate diversions are 50,970 acre-feet, and delivery from Empire Reservoir is about 15,900 AF (0.83 AF/acre). The District's diversion structure consists of two components: 1) the ditch intake structure, which consists of a structure with 5 steel radial gates to adjust flows into the Empire Intake Canal, and 2) the river diversion structure, used to divert flow into the ditch intake structure. The diversion structure had suffered extreme damage in times of high flow in the river. It previously used a removable board system to control water levels in the river, which had lost its effectiveness due to large sand build-up on the upstream side. The diversion also had problems with debris, mainly trees getting caught in the structure, requiring continual maintenance. The original intent of this project was to make repairs to the river diversion portion of the structure only, by constructing a 100 foot long Bladder Gate, located immediately adjacent to the ditch intake structure. Discussion ~ Due to additional work not programmed in the original cost estimate, due to unforeseen site conditions encountered in the field, the overall cost of the project has increased significantly. Upon removal of the 100-foot section of diversion structure located adjacent to the intake structure it was discovered that the remaining 180-feet of structure had been severely undermined. The extent of the void was unknown and given the cost of replacing the entire structure, the District first elected to fill the void with concrete. After the placement of 100 cubic yards of concrete and no visible improvement to the problem, the District realized that full replacement of the structure would be required. The replacement structure consists of 100-feet of 5 foot high Bladder Gates and 180 feet of concrete rollover dam. Additionally, it was decided in order to adequately address the sand and debris problem, the intake structure would need to be reconstructed and realigned. Currently, the structure does not align perpendicular to the river and creates a sediment trap next to the intake structure. Therefore, to allow the gates in the river to function as designed, the location and configuration of the intake needs to be modified. The new intake structure will be modified to align with the river and the five existing steel radial gates will be replaced with two 25-foot wide Bladder Gates. The total cost for the improvements described above is $1,206,760. These improvements were not included in the original cost estimate. A comparison of the total cost of the project with that originally estimated is summarized below in Table 1. Nation Engineering, Fort ~torgan, Colorado, completed the cost estimate for the project in August of 2007. The estimated total cost of the project at the time of loan approval was $720,000.