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Research about Millard County, Utah

Source-linked reports with geographic coverage including Millard County, Utah.

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Hydrologic reconnaissance of the Sevier Lake area, west-central Utah

The hydrologic system of the Sevier Lake area, at the terminus of the Sevier Lake drainage basin in west-central Utah, was studied during 1987-88 to determine baseline hydrologic conditions prior to anticipated development. Sevier Lake was reestablished during 1983-87 on the normally dry playa as a result of record volumes of surface-water runoff, but the lake was receding during the study. In June 1985, the lake reached a maximum depth of about 13 feet, with a water-surface altitude of 4,527 feet above sea level. The basin-fill aquifer includes a coarse-grained facies at higher altitudes of the alluvial slopes, and a fine-grained facies at lower altitudes around Sevier Lake. Water levels indicate a potential for lateral groundwater movement away from the lake and toward the northwest, west, and south. Transmissivity of the coarse-grained facies, determined from one well, was 4,120 feet squared per day. Transmissivity values for the fine-grained facies ranged from 1 X 10 -3 to 5 X 10 -2 foot squared per day, determined from slug tests of shallow wells near the shoreline of the lake, and 5.2 feet squared per day determined from a well in the lakebed. The predominant constituents of water sampled in the Sevier Lake area are sodium, sulfate, and chloride. The concentration of dissolved solids ranges from 480 to 120,000 milligrams per liter. Smaller concentrations of dissolved solids were determined for water from wells completed in the coarse-grained facies, and larger concentrations were determined for water from wells completed in the fine-grained facies.

Utah

Selected hydrologic data for Pahvant Valley and adjacent areas, Millard County, Utah, 1987

This report contains hydrologic data collected in Pahvant Valley and adjacent areas from 1909 to 1987. The report area is mainly comprised of Pahvant Valley on the east and the southern part of the Sevier Desert on the west (plate 1). The area is in west-central Utah, within the Basin and Range physiographic province, and includes about 1,600 square miles. Most of the data in this report were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, from 1985 to 1987. Some of the earlier data were previously published by Enright and Holmes (1982), Meinzer (1911), Mower (1963 and 1967), and Mundorff (1970). The purpose of this report is to provide hydrologic data for use by the general public and by officials managing the area's water resources, and to supplement interpretive reports for the area. Tables 1 to 6 contain information about wells including well completions, drillers' logs, water levels, flowing-well discharges, and chemical quality. Spring and surfacewater site data are listed in tables 7 to 9. Hydrologic-data sites are shown on plate 1.

Utah

Seepage study of a 15.3-mile section of the central Utah canal, Pahvant Valley, Millard County, Utah

Three sets of seepage measurements were made at ten canal sites and at all turnouts along a 15.3-mile section of the Central Utah Canal during the summer of 1986. The total loss for the 15.3-mile section averaged about 36 cubic feet per second or 2.4 cubic feet per second per mile. The nine subsections were grouped into five reaches of one or more subsections with similar losses per mile. Average losses for these five reaches ranged from 0 to 4.1 cubic feet per second per mile. No average gains were detected.

Utah

Causes of fluctuations in the rate of discharge of Clear Lake Springs, Millard County, Utah

The Clear Lake Springs in southeastern Millard County are the source of water for the maintenance of the Clear Lakes Migratory Waterfowl Refuge. Seasonal declines in the rate of discharge were noted during 1959-60. Fluctuations in the flow of Clear Lake Springs are caused both by natural variations in the quantity of recharge and by variations in the quantity of water pumped from an increasing number of irrigation wells in the southern four districts of adjacent Pavant Valley. The springs are the principal discharge point for an aquifer in a complex of highly permeable basalt flows. Water enters the basalt aquifer as direct recharge from precipitation, as interformational leakage from a contiguous artesian aquifer in lake and alluvial sediments, and as infiltration of infrequent flood runoff and of unconsumed irrigation water in the lowlands of Pavant Valley. A hydrograph of the flow of the springs indicates that precipitation on the basalt outcrop recharges the aquifer; this conclusion is strengthened by fluctuations in the chemical quality of the spring water. The effects due to precipitation, however, are partly masked by the larger effects due to the pumping of ground water for irrigation in southern Pavant Valley. Withdrawal of ground water from wells in the southern four districts causes seasonal reductions in the flow of the springs by reducing the hydraulic gradient between the wells and the springs. Statistical analysis of three parameters - the (1) October-April precipitation, (2) annual pumpage, and (3) annual lowest rate of spring discharge - shows that a departure of 1 inch from the normal October-April precipitation at Fillmore is accompanied by a change of 0.41 cubic feet per second in the low flow of Clear Lake Springs. Similarly, a departure of 1,000 acre-feet from the 1961-64 average annual pumpage causes the low flow of the springs to change by 0.23 cubic feet per second. The average annual volume of discharge from Clear Lake Springs during 1960-64 was 14,900 acre-feet. The equation derived from the statistical analysis shows that of the average annual discharge, 3,000 acre-feet of water was derived from precipitation on the basalt, 9,000 acre-feet, from underflow from Pavant Valley, and 2,900 acre-feet, from undetermined sources.

Utah

Ground water in Pavant Valley

The users of wells for irrigation in Pavant Valley, particularly in the Flowell district, have long been cognizant of their utter dependency upon ground water for livelihood, and were among the first in the State to make an organized effort to conserve supplies by prevention of waste. Since passage of the State ground-water law in 1935, the State Engineer has not approved applications for new wells in the areas of most concentrated development, and has deferred adjudication of existing water rights until adequate data concerning the ground-water resources become available. The investigation of ground-water resources in Pavant Valley was suggested by the State Engineer and constitutes one of a series that are being made in the important groundwater basins of Utah by the Federal Geological Survey in cooperation with the State Engineer. The investigation was under the general supervision of Oscar E. Meinzer, geologist in charge of the ground-water division of the Federal Geological Survey. H. E. Thomas, in charge of groundwater investigations in Utah, returned from military service overseas in time to assist in the completion of the manuscript, and edited the report.

Utah