Laserfiche WebLink
<br />r--- <br />"'. <br />. '. <br /> <br />t.C <br /> <br />Farmers' Water Development Company. 1990 Operations <br /> <br />;.. <br /> <br />Forewarned of the potential magnitude and the potential consequences of the drought, the <br />Farmers' Company initiated drought operations early in the season. The runoff forecasts <br />provided by the Soil Conservation Service (SCS) gave an indication of the potential severity of <br />the drought. The projected shortages under various operating scenarios provided by the <br />operations model gave an indication of the consequences of the drought. Key eiements of the <br />drought operations implemented were the delaying of reservoir releases until mid-May and <br />elimination of the free-water period. <br /> <br />Reservoir releases were delayed until May 15 even though crops in the lower portions of the <br />service area could have used the water two to three weeks earlier, This was done primarily to <br />save water for use later in the season by physically keeping it in the reservoir, In addition, this <br />mode of operation was intended to conserve water by making larger releases when releases <br />began, thereby producing lower ditch transit losses. <br /> <br />Elimination of the free-water period put the system on a user-call basis immediately. This <br />allowed individuals greater flexibility in using their water in the manner they chose once releases <br />commenced on May 15. Many individuals used their water rapidly, apparently hoping to <br />produce as much forage as possible as early as possible before the grass went to seed or <br />became dormant. Other individuals apparently chose to ration their supply more uniformly <br />across the season or to use their water in blocks in selected periods. Irrigators who chose to <br />ration their water over the season were reportedly targeting coverages of approximately 20 to <br />50 percent of their iand. These percentages were generally in-line with the projected 20 to 30 <br />percent coverage necessary to provide late season water through July determined on the basis <br />of the runoff forecasts and operations model results. Other individuals, primarily absentee <br />shareholders, chose to forego any irrigation at all. Releases from Gurley Reservoir were cut.off <br />on July 26, 1990, except for a continuous small release of approximately 1 cfs to supply the <br />WMRWS, <br /> <br />Records of the selected mode of operations on a shareholder by shareholder basis were not <br />compiled for this report. Average daily inflows, outflows, and storage volumes at Gurley <br />Reservoir were compiled to illustrate the overall system operations over the period of April <br />through August. This data were obtained from ditch company personnel and from the CWCS, <br /> <br />The data are displayed in Table 1, with average and peak reservoir inflows and outflows in cfs, <br />reservoir stage in feet, and reservoir storage content in acre-feet on a daily basis provided. The <br />average daily inflows and outflows are displayed graphically on Figure 1, The reservoir storage <br />contents are displayed graphically on Figure 2. These data and figures reflect the operations as <br />described above. <br /> <br />Examination of the inflow and storage records show that approximately 8600 acre-feet of runoff <br />were captured between April and July. A volume of 1600 acre-feet of carryover storage and <br />winter inflow was in place on April 1 for a total volume of approximately 10,200 acre-feet <br />available during the irrigation season, The actual April to July inflow volume matched the value <br />of 6700 acre. feet predicted for the Gurley system by the March and April SCS forecasts <br />