OCR Text |
Show The water from the front streams and Provo River is high quality, suitable for municipal and light industrial uses. The Utah Lake and Jordan River waters are of lower quality and are suitable only for irrigation and heavy industrial use due to the concentration of dissolved solids which exceeds 1,000 mg/ 1.93, 150 During the water years 196U- 68 the mean annual surface inflow to Jordan Valley was U63,000 acre- feet, and the outflow discharged to Great Salt Lake was 32^, 000 acre- feet. Total diversions from surface sources during this period were l^ fOOO acre- feet plus an additional 205,000 acre- feet diverted for wildlife use at the lower - end of the valley. Thus, it is evident that there is considerable use and reuse of irrigation return flows , surface wastewater from the valley floor and groundwater entering the Jordan River system. All flows available within present municipal and industrial and irrigation demand patterns are presently utilized. Only the high runoff or flood flows, winter flows, and other wastewater is discharged to the Great Salt Lake. The contribution by the mountain front streams for the period from 196U through 1968 was 1^ 9,^ 00 acre- feet annually. Of this amount 5^ » 000 acre- feet are diverted for municipal and industrial use and U0,000 acre- feet for irrigation. Irrigation rights on these streams are being exchanged for municipal and industrial use by replacement with Utah Lake water. It is expected that this trend would continue until all of the usable water is so exchanged. Water is also available to Salt Lake County from the Provo River system and is delivered by the Salt Lake Aqueduct, Provo Reservoir Canal, and by the Utah Lake Distribution Company Canal in accordance with exchange agreements. The Metropolitan Water District of Salt Lake City has a normal allocation of about 56,800 acre- feet of storage capacity in Deer Creek Reservoir. In a " normal year" more water is available than is used. However, in dry years deliveries in excess of supply are made from the carryover storage. In order for a municipal supply to be firm, it must be available during a series of dry years. This requires storage capacity that can be filled during above normal runoff years and used during drought periods. As the municipal demand increases, the requirement for carryover storage must also increase if the supply is to remain firm and without shortage. 174 |