| OCR Text |
Show I sreelsen, Maughan and South: Irrigation Companies 35 Class II. Supply is below Class I, but more than one-half ade quate for irrigation season, with usable amounts avail able in low-water season of average Class III. Supply is below Class II, amounting to no more than a hiqh-water supply or the equivalent. Irrigation System years. _ The survey lists 13 reservoirs with a combined storage ca pacity of 27,216 acre-feet belonging to six companies in Sanpete County. The needs for additional storage water and plans for construction of reservoirs have been pointed out. However, the additional water provided by feasible reservoir construction will fall short of satisfying the needs for supplemental water. This, then, emphasizes the importance of utilizing other means of sup plying the deficit. Foremost among these possibilities is to in crease the efficiencies in diverting, conveying, delivering, and utilizing available supplies. In general. it may be said that irrigation systems in Utah are only in fair working condition. Some are badly run down, while some are demonstrating efficiency of operation. Conoeqence losses may not be easy to detect and may' escape unnoticed unless systematic effort is made to ferret them out. The most setisjec tory method is by water meesurement=-to determine through measurement the diversions to the company and by the same method, the delivery of water to users. Without careful mees utements excessive losses may be sustained indefinitely without detection. The canals of the 28 larger companies in Sanpete County have an average capacity of 41.3 second-feet, ranging from three to 200 second-feet per company. The combined capacity of all is 1,158 second-feet. The total length of these canals is 138 miles with an average of 4.9. They range from less than a mile to 20 miles in length. The main laterals under these canals in size from 4 to 20 second- feet, and from less than one mile vary to 30 miles. (The total length of all is 173 miles.) Irrigation companies report 20 miles of canals and laterals in need of lining to reduce seepage losses and 46 miles requiring major cleaning, enlargement or realignment to place them in ade quate working condition. The need of improvements in canal The diversion, control, and measurement require diversion structures, weirs, siphons, flumes, dividers, gates, and other similar devices built for that pur pose. These structures often represent the "critical links" in the distribution system and they may be the controlling factors in the efficiency of water diversion, conveyance and delivery. Economic Aspects The irrigation company reveals that few structures is extensive. of water in the canal ... study companies |
