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Show use patterns go unchanged, the existing total M& I use for Salt Lake County is expected to increase from 331,500 acre- feet in 1995 to 496,500 acre- feet in the year 2020. The average annual irrigation diversion needs ( 1995) for the Jordan River Basin are 126,500 acre- feet. Due to the growing residential development and declining amount of agricultural land, it is anticipated that irrigation diversions and depletions will decrease to 71,000 acre- feet bv the year 2020. ( See Section 10) 17.3 Water Conservation Opportunities The 1992 Central Utah Project Completion Act ( CUPCA) requires 39,325 acre- feet of water conservation within the project service area by the year 2007. The CUPCA authorized the appropriation of $ 50 million of federal funds for conservation measures. To date, less than $ 4 million has been appropriated. This money is available on a 65- 35 percentage cost share with the 65 coming from project funds. This section includes a discussion of municipal and industrial ( M& I) conservation and agricultural water conservation practices. Agricultural water is untreated water, usually of poorer quality used specifically for production of crops. By definition, M& I refers to all public water use. Therefore, untreated " secondary" water is included in the broad category of municipal and industrial water. The vast majority of M& I water is treated culinary water as a part of the public water systems. It is used for residential, commercial and industrial purposes, and is treated to meet the strict regulations of its highest use - drinking water. Consequently, M& I water is expensive, especially when compared with the price of agricultural water. Obviously, water conservation strategies for these two different types of water use are varied. 17.3.1 Agricultural Water Conservation A land use inventory for Salt Lake Valley completed in 1994 determined irrigated agricultural lands covered 25,300 acres. The current water rights allotment is five acre- feet per acre. This means approximately 126,500 acre- feet of water are diverted annually for agricultural irrigation. Of the five acre- feet duty ( allotment), about 2.3 acre- feet per acre is used for crop consumption. The remaining 2.7 acre- feet per acre is for conveyance and application losses. Clearly, there is potential to conserve agricultural irrigation water. Irrigation diversions can be reduced by eliminating conveyance losses such as canal seepage, and improving irrigation scheduling during the growing season. Canal operation and maintenance is a constant activity of irrigation companies. Sprinkler irrigation may improve on- farm efficiencies. But studies have shown that Utah Lake water, when sprinkled on leaves, creates a salt toxicity danger to crops. In addition, decreasing the Utah Lake duty on farmlands reduces the flushing in the root zone, which can create a salt toxicity build- up and damage crops. Although there is a real potential to conserve Jordan River irrigation water, there is no real incentive to do so. As pointed out in previous sections ( See sections 5, 7 and 10 for details), there is sufficient agricultural irrigation water supply for the existing demand. There is no foreseeable need for additional agricultural water. Also, because Jordan River water quality is poor, it is not presently economically feasible to treat it for municipal use. 17.3.2 Municipal and Industrial Water Conservation Conservation of municipal and industrial water is an appropriate and feasible way to meet part of the future water requirements. However, satisfying all of the projected growth through conservation is not possible. The county population is projected to increase about 62 percent ( 495,100 people) by the year 2020 ( See Section 4). Coupled with the current water consumption rate, this projected growth will increase the M& I water demand from 331,500 acre- feet to 496,500 acre- feet by the year 2020. This increased water demand will most likely be met through a combination of actions including water conservation, new wells, water import from outside the basin, and treating additional surface water. Some effective water conservation measures could be employed to significantly reduce municipal water use. Unmetered water use and system losses amount to 21,400 acre- feet. This figure is projected to increase to about 40,000 acre- feet over the next 25 years. Although the unmetered uses include fire fighting and park watering,- the potential still exists for conserving residential water through maintenance and monitoring. The city of West Jordan recently computerized its lawn watering system for 150 acres of parks, cemeteries and recreational areas. The city 17- 2 |