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W. L. Steinhilber

Publications and source records attributed to W. L. Steinhilber.

8 recordsLinked to original sources
USGS1978

Jordan aquifer of Iowa

Water demand for all uses in Iowa is increasing at an accelerated rate. Demand has increased from about 1,800 million gallons per day in 1955 to 3,500 million gallons per day in 1975 (MacKichan, 1957; Murray and Reeves, 1977). By the year 2020, water demand is expected to be eight times that in 1975 (Barnard and Dent, 1976). Historically, about 75 percent of the demand, excluding that required for power generation, has been met by withdrawals from the water-bearing zones (aquifers) in Iowa's ground-water reservoir. Because this percentage is expected to remain about the same, the anticipated future demands will require extensive withdrawals from the ground-water reservoir. The increasing stress on the ground-water system, which already is severely stressed in several places in the state, will create development and management problems that will require hydrologic information to solve. In order to provide this information, the lowa Geological Survey in cooperation with the U.S. Geological Survey has instituted a series of investigations to define, describe, and evaluate the major aquifers in Iowa's groundwater reservoir. Information from each investigation will be presented in atlas format.

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USGS1977

Geohydrology of Muscatine Island, Muscatine County, Iowa

Muscatine Island is a wide segment of the west bank of the Mississippi River flood plain that covers about 50 square miles in Muscatine and Louisa Counties; the project area encompasses the 30 square miles in Muscatine County. The flood plain is underlain by thick, permeable alluvial deposits that comprise a water-table aquifer that is developed extensively for water supplies in the area. The aquifer consists principally of sand and gravel, interbedded with lenses of silt and clay. Its saturated thickness ranges from about 40 to 140 feet. The transmissivity and storage coefficients of the aquifer range from about 20,000 ft. 2 /day and 0.15. respectively, in the western part of the Island to about 39,500 ft.2/day and 0.24 in the eastern part. The amount of water stored in the aquifer, under normal conditions, is about 100 billion gallons. Discharge from the aquifer is principally by pumpage, which has increased from about 1 mgd (million gallons per day) in 1906 to about 37 mgd in 1970. About 2.5 mgd is normally lost to seepage and evapotranspiration along a 9-mile reach of Muscatine Slough in Muscatine County. About 0.9 mgd is discharged by evaporation from gravel pits. Recharge to the aquifer is by induced infiltration from the Mississippi River, seepage from the river during major flood events, precipitation, and seepage from the underlying limestone bedrock. Induced infiltration provides about 80 to 85 percent of the water withdrawn from the principal pumping centers along the river and also replaces about 70 to 80 percent of the water that is evaporated from the gravel pits; this amounted to about 30 mgd in 1971. Additional significant recharge from the river occurs during major floods, when prolonged high stages provide the head for considerable underflow to the aquifer. Recharge from precipitation on the Island was calculated to average about 6inches per year or about 0.3 mgd per square mile. Seepage from bedrock is significant and is attributed to the increased head differential between the alluvial and bedrock aquifers in the areas of major pumping. The chemical constituents of water from the aquifer are generally within the recommended limits established by the U. S. Public Health Service for drinking water. Stresses on the hydrologic system have affected the position and configuration of the water table and the chemical quality of the ground water. The large-scale withdrawals, which began at the principal pumping centers in 1946, have caused the water table to decline from about 1 foot in the interior of the Island to about 5 feet near the edges of the main pumping centers; the decline was more than 8 feet under the pumping centers. A slight increase in hardness of water from riverward wells in the pumping centers is attributed to the induced infiltration of slightly harder river water; a noticeable increase in hardness and iron content in water from landward wells is attributed to seepage of water from the bedrock. In the central irrigated area, which is underlain by very permeable, highly drained soils that are mulched with organic fertilizers, the nitrate content of the ground water is as high as 46 mg/l (milligrams per liter). Land-use practices have had, and probably will continue to have, an impact on the quality and quantity of water available in the system. The hydrologic system in 1971 was in dynamic equilibrium or in near-equilibrium with the stresses imposed on it to that date. This equilibrium would be disturbed by any additional stresses on the system and water levels would change until a new equilibrium was established. The effects of future stresses can be reasonably predicted by developing a digital model of the system. The data to develop such a model are available in this report. Continued and expanded monitoring of water levels would provide data for better model verification. Periodic monitoring of nitrate and other chemical constituents would permit early detection of changes in concentration before the concentrations reached excessive levels.

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USGS1970

Geology and ground-water resources of Cerro Gordo County, Iowa

The basic geologic framework underlying Cerro Gordo County consists of an igneous or metamorphic Precambrian basement complex overlain by, in ascending order, consolidated sedimentary rocks of Precambrian, Cambrian, Ordovician, Devonian, Mississippian, and Cretaceous age, and unconsolidated sand, gravel, and clay of Quaternary age. Structurally the county is in the northern part of the Iowan Basin, and the sedimentary units of Cambrian through Devonian age dip southward at 9 to 14 feet per mile. Three major glacial advances, the Nebraskan, Kansan, and Wisconsin, covered all or part of the county during the Pleistocene Epoch and left behind glacial drift consisting of 0 to 125 feet of till and related outwash deposits. De posits of Holocene age, aside from surficial soil, are thin and scattered. Ground water occurs in the sedimentary units of Cambrian through Mississippian age and in the glacial drift and outwash deposits of Quaternary age. The chief aquifers, in ascending order, are the deep Cambrian sandstones, Jordan aquifer, St. Peter Sandstone, Devonian and Mississippian limestones and dolomites, and the Pleistocene glacial drift and related interglacial deposits. Units between the St. Peter Sandstone and the Devonian limestones, the Platteville, Decorah, Galena, and Maquoketa Formations, are of low permeability and are considered to be an aquiclude in comparison to the overlying and under lying units. The deep Cambrian sandstones will yield about 60 gpm (gallons per minute) to an individual well; the Jordan aquifer about 1,200 gpm; the St. Peter Sandstone 30 to 200 gpm; the Devonian limestones and dolomites 120 to 200 gpm; and the glacial outwash or shallow bedrock generally will yield 10 gpm or more. The Jordan aquifer supplies large quantities of water for municipal and industrial use at Mason City. Pumping tests on wells tapping the Jordan in that area show that the aquifer has a transmissibility of about 35,000 gallons per day per foot and a storage coefficient of 2 x 10 -4 Pumping in the Mason City area from 1912 to 1969 has produced about 200 feet of draw down in the areas of maximum withdrawal. Ground water in Cerro Gordo County is of suitable chemical quality for domestic, industrial, or municipal use. The total dis solved solids ranges from 152 mg/l (milligrams per liter) in water from the shallow bedrock to 885 mg/l in water from the deep Cambrian sandstones. Water from the Jordan, which is the most productive aquifer in the county, generally contains less than 500 mg/l dissolved solids. Ground water is the major source of water supplies throughout Cerro Gordo County. The majority of wells in the county are used for domestic and stock supplies, but the largest withdrawals of water are for municipal and industrial supplies. Municipal pumpage in the county in 1968 was about 1.5 billion gallons; industrial pumpage was about 1.8 billion gallons and most of the water was obtained from the Jordan aquifer. If future development of water from the Jordan aquifer is to be to the best economical advantage, careful consideration should be given to the location, capacity, and pumping schedules of proposed wells and nearby existing wells so that local overdevelopment or excessive interference do not occur.

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USGS1967

Availability of ground water in Decatur County, Iowa

Decatur County and several other counties in south-central Iowa comprise an area that has been chronically short of good-quality water. Municipalities, industries and rural water users alike have been affected by the water shortage. Municipalities have experienced serious problems in obtaining potable supplies adequate to keep pace with their growth and development: industrial expansion has been hindered and continues to be hindered by the shortage of good-quality water; and rural supplies for domestic and livestock use are difficult to obtain at many places. The increased use of water for all purposes and periodic drought conditions have greatly magnified an already serious problem of water shortage.

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USGS1961

Geology and ground-water resources of Clayton County, Iowa

Clayton County includes 784 square miles in northeastern Iowa and in 1960 had a population of 21, 962. For the most part, the county is a dissected upland that is drained mainly by the southeastward flowing Turkey River and its principal tributary, the Volga River. The Turkey River empties into the Mississippi River, which flows southward along the eastern border of the county. The climate is humid continental, and the average annual precipitation is 33.01 inches. The economy of the county is based on farming and the raising of livestock. The natural resources of the county include soil, water, rock, sand, and timber.

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