Laserfiche WebLink
<br />Even though the amount of usable surplusiwat!lr may be limited, <br />there are opportunities to increase the supply by more efficient utiliza- <br />tion. Substantial saving could be made by ~ore efficient application of <br />water for irrigation. Irrigators should apply only enough to provide for <br />plant growth plus the excess needed to. carry away dissolvedmineral.s, <br />Investigations of the relation of water application to optimum producti- <br />vity, followed by an educational program, might result in substantial <br />saving of water as well as improvement in ~rop yield. Industries have <br />effected substantial savings by condensing '"team, recirculating cooling <br />water, and by treating and re-using water. The cost of these measures <br />may be small compared with the cost of new water. Industries along the <br />Gulf Coast utilize water from brackish streams and bayous in p,rocesses <br />where good quality of water is not essential and reserve gOOd water for <br />the processes that require it. Domestic sewage, properly treated, can <br />be used in industry or agriculture with perfect safety. <br /> <br />Water might be conserved by utili2;inga larger proportion of pre- <br />cipitation for man's benefit. On the average, about 70% of precipitation <br />is lost by evaporation or transpiration. BElcause precipitation is erratic, <br />storage is essential in making water availa;ble for beneficial use. <br />Streams are dammed by man to store watet until needed. Nature's <br />groundwater reservoirs dwarf man-made surface reservoirs, and do not <br />lose water by evaporation. A substantial amount would be salvaged if <br />more water from surface reservoirs were artificially introduced into <br />groundwater reservoirs. Water loving plants, called phreatophytes, <br />transpire great quantities of water and thus reduce the amounts available <br />for beneficial uses. They also concentrate the mineral.s in the remaining <br />water, making it less desirable for downs~ream use. T. W. Robinson <br />has estimated the total use by phreatophyt~s in the 17 western states at 2.0 <br />to 25 million acre-feet a year, a substantial part in the Colorado River <br />. Basin. Better control of forest growthlikewise offers opportunity for <br />salvaging water. The Forest Service reports that periodic thinning and <br />harvesting of young trees could permanently increase water yield 250/0. <br />Substituting grass for brush cover would save water. <br /> <br />" <br /> <br />. <br /> <br />.' <br /> <br />. <br /> <br />Many western streams are polluted ]:>y brine springs. Clifton <br />Springs feeds 70 tons of salt daily into Gila River .and only two acre-feet <br />of water. Preventing these .brines from r~aching the rivers would increase <br />the total supply suitable for irrigation, T:ransmountain diversions will <br />affect the quality of water downstream. 'I'he upper tributaries of <br />Colorado River have dissolved solids undElr 100 parts per million, where- <br />as water flowing into Lake Mead has about 600. What will be the effect <br />on water in downstream reaches if lOa-part water is taken out of the <br />Ba sin? <br /> <br />There is hope that more efficient use of water can be made because <br />understanding of the hydrology of water r~sources shows radical. improve- <br />ment. Deficiencies in basic data, recognized by every group that has con- <br />sidered national water problems, are slowly being corrected with full <br />support from the people. It is my belief that if we make the most <br />efficient use of our water resources, they will be adequate for our needs <br />indefini tel y . <br /> <br />., <br /> <br />. <br /> <br />-36- <br />