The D.M.A.D. dam and reservoir are located on the Servier River northeast of Delta, utah, and serve as a stroage reservoir for the winter and spring flows of the Sevier River below Sevier Bridge Reservoir. The D.M.A.D. dam has been constructed with two outlet works, one for feeding Canal "A", which serves the Delta and Melville Irrigation Companies, while the other canal serves the Abraham and Desert Irrigation Companies.
A gaging station located along Canal"A" has been used for many years to obtain flow measurements. The gaging station measurements appeared to be very inconsistent, and consequently, in 1963 a study was made to evaluate the accuracy of the station. The results of the study (Figure 1) showed that for a constant depth of flow, the flow rate might vary more than a foot. The flows conveyed by this canal range from 15 to 500 cfs.
Canal "A" is five miles in length and has a total drop in grade of five feet, the average slope therefore being one foot per mile. Regulation of the end of the canal will cause backwater effects over the entire length of the canal. The backwater effects will result in increased seepage losses. The installation of a Parshall flume was contemplated for measuring the flows conveyed by Canal "A" but it would be necessary to place the floor of the flume 2.75 feet above the canal grade to insure free flow over the entire flow range. The use of such a flume would significantly increase the seepage losses between the measuring station adn the dam for all flows below the design discharge of 500 cfs. Since the D.M.A.D. reservoir is used primarily for regulation, increasing the water levels in Canal "A" would reduce the regulating head and the usefulness of the lower storage levels in the reservoir for the Delta and Melville Irrigation Companies.
Skogerboe, Gaylord V.; Walker, W. Roger; and Robinson, Lawrence R., "Design, Operation, and Calibration of the Canal "A" Submerged Rectangular Measuring Flume" (1965). Reports. Paper 77.