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Research about Iowa

Source-linked reports with geographic coverage including Iowa.

At least 361 records · Page 20Linked to original sources
USGS1986

Discharge ratings for control gates at Mississippi River Lock and Dam 16, Muscatine, Iowa

The water level of the navigation pools on the Mississippi River are maintained by the operation of tainter and roller gates at the lock and dams. Discharge ratings for the gates on Lock and Dam 16, at Muscatine, Iowa, were developed from current-meter discharge measurements made in the forebays of the gate structures. Methodology is given to accurately compute the gate openings of the tainter gates. Discharge coefficients, in equations that express discharge as a function of tailwater depth, headwater depth, and vertical height of gate opening, were determined for conditions of submerged-orifice flow. A comparison of the rating discharges to the hydraulic-model rating discharges is given for submerged-orifice flow for the tainter and roller gates. (Author's abstract)

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USGS1986

Hydrology of carbonate aquifers in southwestern Linn County and adjacent parts of Benton, Iowa, and Johnson Counties, Iowa

Groundwater is the major source of water in Linn County and the surrounding area. Approximately 90 percent of the groundwater production is from Silurian, Devonian, and Quaternary aquifers. The Silurian and Devonian aquifers consist of limestone and dolomite with minor shale beds, which have a regional dip to the southwest of approximately 20 feet per mile. The Silurian aquifer in east-central Iowa is confined from below by Upper Ordovician, Maquoketa Formation shales, and from above by the Kenwood Member of the Wapsipinicon Formation and the Otis and Bertram formations. The Quaternary aquifer consists of unconsolidated sand and gravel beds in the glacial drift, and in the alluvium which is associated with modern streams. The alluvium consists of lenticular beds of poorly-to well-sorted silt, sand, and gravel. The sand and gravel beds are interlayered with relatively-impermeable beds of till, silt, and clay. Water moves through the Silurian aquifer in part due to a complex distribution of porous and dense carbonate facies. Horizons containing skeletal molds in the Silurian dolomite have porosities as much as 39 percent, and are laterally equivalent to dolomites with porosities as little as less than one percent. Because of subsequent fracturing and solutional enlargement of these porous horizons, hydrologic correlation of the primary water-yielding zones is not always possible. One horizon, however, does occur approximately 70 to 105 feet above the base of the Silurian, and is the most consistently productive water-yielding unit in the area. This horizon is Informally referred to as the Farmers Creek aquifer. The potentiometric surface of the Silurian aquifer has a gradient towards the Cedar River, indicating discharge from the aquifer through the alluvium into the river. By comparison, the potentiometric surface of the overlying Devonian aquifer is equal to that of the Silurian and may range to more than 40 feet higher. Yields to individual wells completed in the Silurian and Devonian carbonate aquifers vary from less than 10 to about 500 gallons per minute. Individual wells completed in the Quaternary aquifer yield as much as 2,000 gallons per minute. Water analyses from the Devonian and Silurian aquifers indicate that they are of similar chemical quality at most locations in the study area. However, they may commonly contain concentrations of sulfate that exceed 1,000 mil grams per liter. Dissolved-solids concentrations as much as 2,350 milligrams per liter occur in the Silurian aquifer in the western and southwestern part of the study area. Water from the Quaternary aquifer generally is suitable for most uses and dissolved-solids concentrations generally are less than 750 milligrams per liter.

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USGS1985

Bedrock topography of central Iowa

The bedrock in Iowa (Hershey, 1969) generally is ovelain by deposits of glacial drift and alluvium. The drift, comprised of glacial till and glacial outwash, varies in thickness from less than 1 foot to more than 400 feet; the alluvium in central Iowa varies in thickness from less than 1 foot to about 60 feet. The configuration of the bedrock suface is the result of a complex system of ancient drainage courses which were developed during a long period of preglacial erosion and during shorter, but more intense, periods of interglacial erosion. This map, for a 10 county area in central Iowa, is the seventh of a series of 9 reports that will provide statewide coverage of the bedrock surface of Iowa.

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USGS1985

Iowa ground-water-quality monitoring program

A ground-water-quality monitoring network has been designed to collect data to describe the long-term chemical quality of major bedrock and Quaternary aquifer systems in Iowa. The network was designed because of data needs expressed by several State and Federal agencies. Areas where new or additional data are needed are nitrate and bacteria concentrations in alluvial and glacial drift aquifers, fluoride and radionuclides in deep bedrock aquifers, general quality of water in the Missouri River alluvium, changes in water quality of deep bedrock aquifers caused by large withdrawal, effects of land use on shallow aquifers, and the impact of agricultural injection wells on receiving aquifers. Most of the ground-water-quality monitoring in the State has been directed at compliance or ambient monitoring of municipal water supplies. Some site-specific monitoring has occurred. More recently several special studies or research monitoring activities have been completed or begun. The monitoring program utilizes a strategy that includes low frequency and sparse distribution of samples from Cambrian-Ordovician, Silurian-Devonian, Mississippian,Pennsylvanian, and Dakota aquifers. A larger density and greater frequency of samples will be obtained from shallow bedrock wells and from wells penetrating Quaternary aquifers suck as alluvial, buried channel, and other drift aquifers. More than 1,200 wells are available and acceptable for the network. From these and newly completed wells, 200 samples will be collected and analyzed annually. Analyses will be made for common anions and cations, trace metals, nutrients, and radionuclides. One out of ten samples will be analyzed for priority pollutants and pesticides. Data from this program will be published annually in Water Resources Data, Iowa, U.S. Geological Survey Water-Data Report.

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USGS1985

Ground-water data for the alluvial, buried channel, Basel Pleistocene and Dakota aquifer in west-central Iowa

The purpose of this investigation was to determine the availability, quantity and quality of groundwater from three principal aquifers in West-Central Iowa, the alluvial, buried channel, Basal Pleistocene and the Dakota aquifers. Specific objectives were to: (1) determine the location, extent and the nature of these aquifers; (2) evaluate the occurrence and movement of groundwater, including the sources of recharge and discharge; (3) estimate the quantities of water stored in the aquifers; (4) estimate the potential yields of wells tapping the aquifers; (5) estimate the water use; and (6) describe the chemical quality of the groundwater. This report is the compilation of the data collected during the investigation and has the purpose of providing a reference for an interpretive report describing groundwater resources and a bedrock topography map of the study area.

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USGS1985

Permitted water use in Iowa, 1985

This report summarizes where, how much and for what purpose water is allocated for use in Iowa with permits issued by the Department of Water, Air and Waste Management. In Iowa, from a total permitted water use of 855,175.45 million gallons per year, about 58 percent is from surface-water sources and about 42 percent is from ground-water sources. Streams are 80.5 percent of the total surface-water use and wells make up 80.1 percent of the total ground-water use, with 65.4 percent of ground water coming from surficial aquifers. Power generation is the use category that is permitted the largest amount of total water use, 46.6 percent, with surface water being the source of 96.7 percent and 77.9 percent of the surface water is from streams. The public water suppliers' category is the next largest use type with 15.7 percent of the total permitted water. Ground water constitutes 74.4 percent of the public water supplier category with 51.7 percent from surficial aquifers. Surface water makes up 25.6 percent of this category with 83.0 percent of the surface water withdrawn from streams. Mining comprises 13.4 percent of the total water use and is the third largest water-use category. Ground water is the source of 63.3 percent of permitted mining water use with 94.3 percent of this from quarries and sand and gravel pits. Surface water is the source of 36.7 percent of the permitted mining water use with 97.6 percent from streams. Irrigation is the fourth largest permitted use type using 12.0 percent of the total water use. Eighty-eight percent of irrigation is from ground-water sources where surficial aquifers account for 94.7 percent. Streams are 81.1 percent of irrigational surface-water use. Self-supplied industrial users are permitted 10.6 percent of the total permitted water use with 85.5 percent of this from ground-water sources and 14.5 percent from surface-water sources. Of the self-supplied industrial ground-water use, 47.9 percent comes from surficial aquifers and of the self-supplied industrial surface-water use 86.1 percent is from streams. Self-supplied commercial use is allocated 1.5 percent of the total permitted water. Surface-water is the source of 37.7 percent of this and 62.3 percent is from ground-water sources. Agricultural (non-irrigation) use is 0.3 percent of the total permitted water with 73.3 percent from groundwater sources and 26.7 percent from surface-water sources. The areas that are allocated the most water permits are east-central Iowa and west-central Iowa.

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USGS1985

Water resources data Iowa, water year 1984

Water resources data for the 1984 water year for Iowa consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; ground-water levels and ground-water quality. This report contains discharge records for 115 gaging stations; stage and contents for 7 lakes and reservoirs; water quality for 17 gaging stations; and water levels for 90 observation wells. Also included are 120 crest-stage partial-record stations. Additional water data were collected at various sites, not part of the systematic data-collection program, and are published as miscellaneous measurements and analyses. The data represent that part of the National Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Iowa.

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USGS1985

Discharge ratings for control gates at Mississippi River Lock and Dam 11, Dubuque, Iowa

The water level of the navigation pools on the Mississippi River are maintained by the operation of tainter and roller gates at locks and dams. Discharge ratings for the gates on Lock and Dam 11, Dubuque, Iowa, were developed from current-meter discharge measurements made in the forebays. Methodology is given to accurately compute the vertical gate openings of the tainter gates. Discharge coeffients, in equations that express discharge as a function of tailwater depth, headwater depth, and vertical height of gate opening, were determined for conditions of submerged-orifice and free-weir flow. A comparison of the rating discharges to the theoretical rating discharges is given for submerged orifice flow for the tainter and roller gates.

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USGS1985

Hydrology of the alluvial, buried channel, basal Pleistocene and Dakota aquifers in west-central Iowa

A ground-water resources investigation in west-central Iowa indicates that water is available from alluvial, buried channel, basal Pleistocene, and Dakota aquifers. The west-central Iowa area includes Audubon, Carrol1, Crawford, Greene, Guthrie, Harrison, Monona, and Shelby Counties. Nine alluvial aquifers consisting of sand and gravel are in the valleys of the Little Sioux, Maple, Soldier, Boyer, West Nishnabotna, East Nishnabotna, South Raccoon, Middle Raccoon, and North Raccoon Rivers. These aquifers contain about 870,000 acre-feet of water that is potentially available to wells. Potential well yields generally are less than 50 gallons per minute. The water generally is very hard (greater than 180 milligrams per liter hardness as calcium carbonate), is a calcium bicarbonate type, and has an average dissolved-solids concentration of less than 600 milligrams per liter. Seven buried channel aquifers Anthon, Denison, Fremont, Hardin Creek, Adaza, Beaver, and Bagley consisting of sand and gravel, underlie about 594 square miles in west-central Iowa and contain about 65,000 acre-feet of water potentially available to wells. Potential well yields of as much as 1,000 gallons per minute are possible in a few of the deeper and thicker parts of some of the buried channel aquifers, but well yields of 10 to 100 gallons per minute are more common. Water generally is very hard, is a calcium bicarbonate type, and has an average dissolved-solids concentration of 400 to 800 milligrams per liter in the shallow buried channel aquifers in Carrol1, Greene, and Guthrie Counties. In the deep buried channel aquifer in Audubon, Crawford, Harrison, Monona, and Shelby counties, the water generally is very hard, is a sodium sulfate or calcium sulfate type, and has an average dissolved-solids concentrations of 3,000 milligrams per liter. The basal Pleistocene aquifer is at the base of the Pleistocene deposits on many bedrock ridges and consists of sand and gravel. Estimated well yields of as much as 500 gallons per minute can be obtained from the aquifer; however, 5 to 50 gallons per minute are more common. Water from the basal Pleistocene aquifer generally is very hard, is a calcium bicarbonate or calcium sulfate type, and has an average dissolved-solids concentration of 1,000 milligrams per liter. The Dakota aquifer consists of the saturated sandstone and gravel units in the Dakota Formation. Isolated erosional remnants of the Dakota Formation form the caps of many bedrock ridges. The Dakota Formation is thickest where the bedrock surface is relatively high and flat, forming an ancient, buried, surface-water divide between southwest and southeast trending buried drainages in Audubon, Carroll, and Guthrie Counties. Sandstone thickness of as much as 150 feet exists in Guthrie County, but an average thickness of 30 feet is more common. Water from wells less than 200 feet deep generally is a calcium bicarbonate type and has an average dissolved-solids concentration of 650 milligrams per liter. Water from wells more than 200 feet deep generally is a calcium sulfate or sodium bicarbonate type and has an average dissolved-solids concentrations of 2,200 milligrams per liter.

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USGS1985

Water resources of north-central Iowa

One of man's fundamental needs is water. Modern man needs both a safe and dependable supply of water to maintain his present economic, industrial, and cultural level. In order to use this natural resource in the most efficient and beneficial manner, a basic knowledge and understanding of water sources, and of the occurrence and potential of each source, needs to be gained. To provide this information, the U.S. Geological Survey, in cooperation with the Iowa Geological Survey, has compiled this atlas. It describes the water resources available for development in an 11-county area in north-central Iowa. The report contains information on the quantity, quality, and use of water from all known sources of water. This information is presented to aid water users and developers who are searching for and evaluating sources of water for specific sites. It also will be an aid to water planners and managers who must develop the available water resources on a regional basis.

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USGS1984

Water resources data Iowa, water year 1983

Water resources data for the 1983 water year for Iowa consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels in wells. This report contains discharge records for 116 gaging stations; stage and contents for 7 lakes and reservoirs; water quality for 17 gaging stations; and water levels for 90 observations wells. Also included are 125 crest-stage partial-record stations. Additional water data were collected at various sites, not part of the systematic data-collection program, and are published as miscellaneous measurements and analyses. The data represent that part of the National Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Iowa.

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USGS1984

Cost-effectiveness of the stream-gaging program in Iowa

This report documents the results of a study of the cost-effectiveness of the stream-gaging program in Iowa. Data uses and funding sources were identified for the 122 surface-water stations (including reservoir, lake, stage only, and miscellaneous stations) operated by the U. S. Geological Survey in Iowa. There are 110 continuous streamflow stations currently being operated in Iowa with an annual budget of $592,000. The average standard error of estimation in continuous streamflow records is 11.4 percent. It was shown that this overall degree of accuracy at the 110 continuous streamflow stations could be improved to 10.5 percent if the gaging schedule was optimized. A minimum budget of $543,000 is required to operate the present streamgaging program in Iowa. With this budget, routine visits to gages would be decreased to five during the open-water season and three during the winter. A budget less than this does not permit proper maintenance of the gages and recorders. At the minimum budget, the average standard error would be 12.5 percent. The maximum budget analyzed was $1,235,000, which resulted in an average standard error of 4.2 percent. A 10 percent increase in the current budget to $656,000 would result in a standard error of 8.4 percent. There are still a few basins with drainage areas greater than 200 square miles that have no continuous streamflow data. Continuous streamflow gages need to be established in these basins as funds become available. All stations in the current program need to be maintained for the forseeable future. Data simulated by using the flow-routing and regression methods for stations in 6 river basins do not meet the accuracy required for their data use. Other basins will be studied later to determine if alternative methods to meet accuracy standards are feasible.

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USGS1984

Availability and quality of water from the Dakota aquifer, northwest Iowa

The Dakota aquifer in northwest Iowa consists of sandstones in the Dakota Formation. It underlies most of the study area and is the most extensive source of ground water in the area. Individual sandstone beds are from less than 10 to more than 150 feet thick. The cumulative thickness of sandstone is more than 200 feet throughout much of the area. The aquifer is confined by overlying Cretaceous limestone and shale, Quaternary glacial deposits and loess. The underlying confining material is shale of the Dakota Formation, undifferentiated Paleozoic age rocks, or Precambrian crystalline rock. Water flows through the aquifer from the northcentral part of the study area to the east, south and southwest. Recharge is dominantly by infiltration from the land surface through the confining materials. Discharge is to underlying Paleozoic aquifers and to the alluvium and glacial outwash deposits along the Missouri and Big Sioux Rivers in the southwest part of the area. Flow components toward bedrock valleys may reflect discharge to Quaternary sand and gravel deposits in these valleys. Pumping tests conducted in the study area indicate a narrow" range of hydraulic conductivities of the Dakota aquifer, from 37 to 50 feet per day. Consequently, an average hydraulic conductivity of 40 feet per day was used to estimate the potential yield to wells completed in the aquifer. Yields of more than 250 gallons per minute can be expected throughout much of the study area and more than 1,000 gallons per minute could be produced in some areas. The quality of water from the Dakota is a calcium, magnesium, sulfate type. It is generally suitable for irrigation purposes, based on comparisons of sodium adsorption ratios and electrical conductivities. In some areas the aquifer has water with high salinity hazard that may restrict its use to irrigation of only well-drained types of soil. The concentration of radium-226 and other radionuclides exceeds recommended limits at several sites. The quality of water pumped from the aquifer may be altered by induced leakage from the underlying aquifers in Paleozoic age rocks if withdrawals reverse the pattern of natural flow from the Dakota into the Paleozoic aquifers. Evidence for such a reversal exists in the area around the city of LeMars.

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USGS1983

Water resources data Iowa, water year 1982

Water resources data for the 1982 water year for Iowa consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels in wells. This report contains discharge records for 116 gaging stations; stage and contents for 7 lakes and reservoirs; water quality for 17 gaging stations; and water levels for 34 observations wells. Also included are 125 creststage partial-record stations. Additional water data were collected at various sites, not part of the systematic data-collection program, and are published as miscellaneous measurements and analyses. The data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Iowa.

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USGS1982

Availability and quality of water from the Dakota aquifer, northwest Iowa

The Dakota aquifer in northwest Iowa consists of sandstones in the Dakota Formation. It underlies most of the study area and is the most extensive source of ground water in the area. Individual sandstone beds are from less than 10 to more than 150 feet thick. The cumulative thickness of sandstone is more than 200 feet throughout much of the area. The aquifer is confined by overlying Cretaceous limestone and shale, Quaternary glacial deposits and loess. The underlying confining material is shale of the Dakota Formation, undifferentiated Paleozoic age rocks, or Precambrian crystalline rock. Water flows through the aquifer from the north-central part of the study area to the east, south and southwest. Recharge is dominantly by infiltration from the land surface through the confining materials. Discharge is to underlying Paleozoic aquifers and to the alluvium and glacial outwash deposits along the Missouri and Big Sioux Rivers in the southwest part of the area. Flow components toward bedrock valleys may reflect discharge to Quaternary sand and gravel deposits in these valleys. Pumping tests conducted in the study area indicate a narrow range of hydraulic conductivities of the Dakota aquifer, from 37 to 50 feet per day. Consequently, an average hydraulic conductivity of 40 feet per day was used to estimate the potential yield to wells completed in the aquifer. Yields of more than 250 gallons per minute can be expected throughout much of the study area and more than 1000 gallons per minute could be produced in some areas. The quality of water from the Dakota is a calcium, magnesium, sulfate type. It is generally suitable for irrigation purposes, based on comparisons of sodium adsorption ratios and electrical conductivities. In some areas the aquifer has water with high salinity hazard that may restrict its use to irrigation of only well drained types of soil. The concentration of radium226 and other radionuclides exceed recommended limits at several sites. The quality of water pumped from the aquifer may be altered by induced leakage from the underlying aquifers in Paleozoic age rocks if withdrawals reverse the pattern of natural flow from the Dakota into the Paleozoic aquifers. Evidence for such a reversal exists in the area around the city of LeMars.

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