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Show The model predicts that over the next 25 years the demand for public water will increase an average of 2.0 percent per year. The 1995 demand for major public water suppliers of 255,700 acre- feet per year will increase nearly 65 percent by the year 2020 to an annual demand of 419,300 acre- feet. Table 9- 3 compares the projected water demand with the existing water supplies. As can be seen from the table, if the model's projected pattern is correct, Salt Lake County will begin experiencing public water supply shortages after the year 2010. These culinary M& I water projections do not include the effects of water conservation measures. The projected effects of water conservation are expected to reduce the projected water use by about 11.4 percent ( 47,700 acre- feet) by the year 2020. With conservation measures Salt Lake County will not begin experiencing shortages until after 2016. Table 9- 4 summarizes 1995 and projected demands for various use categories. Since water sources are fully developed or at the very least fully appropriated, and the basin is closed to further water rights appropriations, it is assumed there will be virtually no new privately developed water supplies. It may turn out, however, that as agricultural lands continue to be converted to residential property, some of the privately developed agricultural water supplies will be converted to public water supplies. However, the potential for converting agricultural water to culinary water will be limited by water quality concerns with Utah Lake and Jordan River water and the high cost of treatment to M& I standards. Table 9- 5 summarizes the total water diversions and depletions for the years 1995, 2020 and 2050. 9.5 Alternatives for Meeting Water Needs Planning for Jordan River Basin's future water needs has become a complex issue. In the past, water planning primarily meant developing new water sources. In the future, there are a number of potential water sources that can be developed to meet the projected water needs. However, they are all expensive. Ultimately, the citizens may be willing to absorb the cost of developing the new and expensive water sources rather than affecting a change in life- style. It is incumbent upon today's water planners to consider the supply- side approach and the demand- side approach to water planning. Although this section is devoted primarily to the discussion of supply- side alternatives ( i. e. developing new water sources), effective demand- side water planning such as water conservation, reuse, reduced system losses, and improved efficiencies, can reduce the need for additional supplies. A brief discussion of water conservation alternatives is included in this section, but a more thorough discussion is included in Section 17, Water Conservation/ Education. Alternatives for meeting future water needs can be classified in six basic groups: ° Develop Utah Lake/ Jordan River water, ° Develop additional water from the Wasatch Range streams, ° Develop additional groundwater, ° Groundwater recharge ° Bear River Water development, ° Conservation Given today's political and environmental climate, some of the alternatives listed above have more merit than others. Based upon current growth projections, meeting the future water demand will require some combination of the alternatives listed above. Possibly, each alternative may at one time or another play a part in the future. A discussion of each alternative along with its relative merits is included in the subsections that follow. 9.5.1 Develop Utah Lake/ Jordan River Water At the present time, a significant supply of water tributary to Utah Lake flows in the Jordan River. This supply source should continue to increase with time as more agricultural lands are converted to residential and commercial uses. Unfortunately, Jordan River water is of poor quality, and it will prove costly to treat it to M& I standards. Total dissolved solids ( TDS) levels in Utah Lake are already so high that conventional treatment of Jordan River water is not economically feasible. As the Jordan River flows northward toward the Great Salt Lake, TDS levels are further increased along with other pollution parameters, including coliform bacteria, inorganics and heavy metals. These problems make the use of the Jordan River for M& I purposes very expensive. Despite these problems, in 1995 the Salt Lake County Water Conservancy District experimented with treating Jordan River water and blending it with high quality water to stretch existing water supplies. Many odor and taste 9- 6 |