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Show OCCURRENCE OF UNDERGROUND WATER. 41 can be obtained at 10 to 50 feet from the surface. The effect of irrigation on ground water in this area, as elsewhere, is marked. Before irrigation was practiced the depth to water was considerably greater than at present; for instance, it is reported that the average level of ground water in several wells in T. 2 S., R. 1 W., now lies 30 to 65 feet nearer the surface than formerly. Besides this more permanent'effect, the ground- water level fluctuates annually from 10 to 15 feet. It is also stated that the quality of ground water has deteriorated in recent years, containing now much more alkali than formerly. So marked has this change been that surface wells are but little valued, and generally water for domestic use is obtained from deep wells. Inspection of the list of wells will show the typical facts of distribution and occurrence of underground water in this region. It will bs observed that many wells are about 250 feet deep and that the range is from less than 100 feet to 1,000 feet. No careful logs have been kept, but from fragmentary information it appears that there is considerable variation in the material encountered in drilling, implying that the sediments are irregularly sorted and that they exist in more or less lenticular arrangement. Accordingly there are no persistent water horizons. Water is generally found in wells wherever sand and gravel are encountered. In several wells a number of water beds are recorded. This water is always under pressure; the height to which it ris? s varies, according to location and elevation, from close to the surface down to 100 feet below it. Generally, fairly good water, within easy pumping distance, is obtainable in this belt of country between the canals and the line of flowing wells. At the Cannon farm, in ssc. 34, T. 2 S., R. 1 W., a well was sunk 1,000 feet in an attempt to get a flow, but although two thin water- bearing beds were found between 600 and 800 feet, from which the water rose to within 30 feet of the surface, flowing water was not obtained. LOWLAND AREA WEST OF JORDAN RIVER. The lowland that lies topographically below the line of flowing wells west of Jordan River is almost a level plain which, along its margin, rises gradually toward the southwest- Local depressions in the plain are occupied by shallow alkaline lakes, which formerly had no outlet but now are drained into Jordan River. The soils of the lowland are chiefly loam and sandy loam, but adjacent to the lake and in local low areas considerable clay is present.** The nature of the underlying deposits is revealed by a number of well records, and ( as would be expected) fine- textured materials are more abundant than nearer the mountains. A few deep wells have been sunk in this general region, proving the great thickness of the old lake deposits. The deepest is the Guffey- Galey well, drilled near the shore of the lake, 2 miles southwest of Farmington and about 10 miles north of Salt Lake City, in an unsuccessful search for oil. b This well was put down 2,000 feet without encountering bed rock. Another deep well is that of the Rio Grande Western Railway at Salt Lake City, which was sunk through alternating beds of sand and clay, with very little gravel, to a depth of 1,073 feet. This is the deepest well in the area under consideration, and its record ( p. 42), as given by the driver, Gus Westphal, is as follows: « A soil survey in Salt Lake Valley: Bull. U. S. Dept. of Agriculture No 64, 1900. & Boutwell, J. M., Oil and asphalt prospects in Salt Lake basin: Bull. U. S. Geol. Survey No. 260, p. 471. |