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J'o. C') ~ For sections where discharge rating equations were to be developed, the cross section was surveyed using a transit. For sections where simply the maximum capacity was to be C evaluated, the cross section was usually surveyed using a hand level. In both cases a surveyors rod with 0.01 foot gradations was used for differential leveling and a 1oo-foot cloth tape was used for measuring distances. At the Ulylands bifurcation structure, a flow of approximately 20.5 cfs was measured corresponding to a stage of 0.54 feet on the staff gage. This value corresponds very well to the value expected for a suppressed, sharp-crested, rectangular weir with a 15 foot crest length even though the Ulylands bifurcation structure is a broad-crested weir. For conversion of stages (H, ft) reported in the operating records to discharges (0, cfs), the following equation for a standard, 15-foot, suppressed rectangular weir was used: 0= 49.95 (H) 1.5. Measured flows of 4.8 cfs in the North Lateral and 15.7 cfs in the South Lateral at the bifurcation structure confirmed that the automatic flow splitter was proportioning the flow in a 20-80 split. Extrapolation from the measurements made indicate that a flow of 50 cts could be accommodated at this location. Measurement of the outflow from Lilylands Reservoir upstream of the bifurcation structure later that day indicated a release rate of approximately 13.2 cfs. Because the measurements at the reservoir and bifurcation structures were instantaneous values and do not reflect flow routing effects or the dynamic nature of flow rates in the system, one cannot quantify overland inflows from these measurements. Extrapolation from the measurements made indicate that a flow rate of approximately 200 cfs could be accommodated at this location, far in excess of the canal capacity downstream. At the Lone Cone Reservoir inflow flume, flows of approximately 8.0 and 13.7 cfs at stages of 0.45 and 0.57 feet, respectively, were measured. Comparison of the flume dimensions measured to those for a standard 8.0 foot Pa~shall Flume show that the throat and diverging section lengths as constructed are longer than standard dimensions. Comparison of the measured discharges to those predicted by the Parshall Flume Equation for a standard 8.0 foot flume show the values to be close, however. Adjustments of the measured stage by + 0.02 foot for use in the calculations brings the measured and predicted flow values into agreement in both cases. The rating equation used to convert stages (H, feet) reported in the operation records to discharges (0, cfs) for the Lone Cone inflow flume was, therefore, as follows: 0= 32.0 (H + 0.02) 1.6066. At the Gurley Reservoir inflow gaging station, flows of approximately 57.5 and 109.6 cfs at stages of 0.5 and 1.0 feet were measured. The section at the gaging station is approximately rectangular with a maximum top width of 26.4 feet. The sides of the channel at the gaging station are vertical concrete walls. The bottom of the channel at the gaging station is excavated to rock, with the floor cut in a slight V-shape and very irregular. Application of Manning's Equation and consideration of the measured flows and channel geometry, led to the development of the following rating equation to convert stages (H, feet) greater than 0.54 feet reported in the operating records to discharges (0, cfs): 0= (1.49/0.06) (23.7 + 26.4 (H-0.54)) 5/3 (26.6 + 2 (H-0.31)) -2/3 (0.0133) 1/2. 2