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Show Geological Survey Reports 1940 Water Level Decline Water levels declined during 1940 In most of the ground-water areas In Utah and thus continued a trend that was begun In 1939 after a rather rath-er general rise during the preceding preced-ing Uiree years, according to data collected and summarized by H. E. Thomas and W. K. Bach of the Geological Survey, United States Department of the Interior, in cooperation co-operation with the State engineer of Utah. Of the 37 ground-water areas Included In-cluded In the study, water levels declined de-clined In 24, rose In 11. and were practically unchanged In 2. The computed average changes which were mostly rather small, amounted to a foot or less In 21 of the 37 areas. Increases In ground-water levels were most marked In observation wells In Juab Valley, and in Pavant Valley, where net changes were 3.8 and 3.4 feet, respectively. The greatest great-est net decline was 1.8 feet in Cedar valley, although net declines were almost as great in Heber Valley, In Utah Lake valley, and in Cache Valley. In Iron County, also, the Parowan Valley area decreased 1.4 and the Escalante Valley, near Beryl decreased .3 feet. In many areas the trend of ground-water levels has followed the trend of precipitation at the near est rainfall station during 1940. Thus, lower water levels in most areas in Iron and Beaver counties are correlated with subnormal precipitation pre-cipitation at all stations in those counties, and the higher levels in Pavant Valley have evidently resulted re-sulted from greater than normal rainfall, as recorded at Fillmore. In the past five years, the trend of water levels has been upward in practically all the Important groundwater ground-water areas in Utah. The groundwater ground-water levels in the state during 1935 were probably lower than at any other time on record, owing to a succession of years of deficient precipitation, pre-cipitation, with resulting subnormal recharge and increased withdrawals from wells. In three exceptional areas the ground-water levels at the end of 1940 were lower than at the end of 1935. In Cedar City Valley the net decline in observation wells was 0.5 foot; in the part of Escalante Valley within Iron county it was 0.4; and in Tooele Valley It was 0.5 foot. The average annual precipitation preci-pitation In Utah during the five-year five-year period, according to data of the weather burea, was 1.8 inches above the 49-year average for the state, and the exceptional decline In these three areas Indicates that ground-water conditions are critical criti-cal and should be watched closely, according to the report. This summary is based upon data collected from "key" wells In each area. A full report contalnin; records from automatic gages on 37 wells and about 4,700 periodic measurements meas-urements In nearly 1,100 wells will be Included in a general report on water . levels in the United States during 1940 to be Issued later by the I Geological Survey. I a I |