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At least 37 records · Page 2Linked to original sources
USGS2007

Characterization of ground-water flow and water quality for the Madison and Minnelusa aquifers in northern Lawrence County, South Dakota

The Madison and Minnelusa aquifers are used extensively for water supplies for the city of Spearfish and other users in northern Lawrence County, South Dakota. Ground water in the Madison and Minnelusa aquifers in the study area generally flows north from outcrop areas where recharge from sinking streams and infiltration of precipitation occurs. Ground water that moves northward and eastward around the Black Hills enters the study area from the west and results in hydraulic heads that are several hundred feet higher on the western side of the study area than on the eastern side. The estimated average recharge rate of 38 cubic feet per second (ft3/s) on outcrops of the Madison Limestone and Minnelusa Formation is less than the total estimated average spring discharge rate of 51 ft3/s in the northwestern part of the study area. Sixteen pounds of fluorescein dye were injected into Spearfish Creek on March 25, 2003, when streamflow was 6.6 ft3/s. The dye was detected in water samples from four wells completed in the Madison aquifer ranging from 2.6 to 4.5 miles north of the injection site. First arrival times ranged from 5 to 169 days, and ground-water velocities ranged from about 0.1 to 0.5 mile per day. Sixty-four pounds of Rhodamine WT was injected into Spearfish Creek at the same location on May 9, 2003, when streamflow was 5.6 ft3/s. Rhodamine WT dye concentrations measured in samples from the same four wells were about an order of magnitude less than measured fluorescein concentrations. Oxygen- and deuterium-isotope values for samples from Cox Lake and McNenny Pond springs indicated a probable component of spring discharge that originates from outcrops of the Madison Limestone and Minnelusa Formation on the Limestone Plateau south of the study area. Oxygen- and deuterium-isotope values for samples from Mirror Lake spring indicated possible contributions from overlying aquifers and local recharge. Oxygen- and deuterium-isotope values for the combined springflow contributing to Crow Creek in the northwestern part of the study area indicated that the primary source of water is the Madison and Minnelusa aquifers. Oxygen- and deuterium-isotope values for Old Hatchery and Higgins Gulch springs, located north of Spearfish, indicated a source water originating from the outcrops of the Madison Limestone and Minnelusa Formation within the study area. Concentrations of three chlorofluorocarbons (CFC-11, CFC-12, and CFC-113) were used to characterize ground-water residence times in the study area. For the four wells where dye was detected, CFC-11 apparent ages ranged from 12 to 26 years, indicating that the wells contained months-old water mixed with years- to decades-old water. Logarithmic regression analysis of the CFC-11 apparent ages for water from 10 wells and distance to a possible conduit trending north through the area where dye was detected, yielded an r2 value of 0.71. Straight-line regression analysis of the CFC-11 apparent ages for the six wells closest to the possible conduit had an r2 value of 0.96. Two wells located relatively close to the outcrop areas had no or very low tritium values indicating relatively long residence times and diffuse ground-water flow. The tritium value of 7.2 TU in water from well COL where dye was detected, indicated that the water probably is a bimodal mixture, with a substantial portion that is older than 50 years. Water from well ELL, where dye was detected, had a tritium value of 19.7 TU and a CFC apparent age of 15 years, indicating that the sample from this well probably is a unimodal mixture with very little water older than 50 years. Comparison of the CFC apparent age for three spring sites (Cox Lake, 26 years; McNenny Pond, 26 years; Mirror Lake, 13 years) also indicated that Mirror Lake spring probably has a component of local recharge from formations that overlie the Minnelusa Formation. In the Madison aquifer, specific conductance ranges from 18 to 945 microsiemens per cen

South Dakota↗
USGS2007

Estimated ground-water use in Becker, Clay, Douglas, Grant, Otter Tail, and Wilkin Counties, Minnesota, for 2030 and 2050

The U.S. Department of the Interior, Bureau of Reclamation, is studying six alternatives for delivering water to the Red River of the North Valley in North Dakota and to the cities of Breckenridge, Moorhead, and East Grand Forks, Minnesota. In order to evaluate these alternatives the Bureau of Reclamation needs estimates of ground-water use for 2030 and 2050 for six counties in Minnesota: Becker, Clay, Douglas, Grant, Otter Tail, and Wilkin Counties. The U.S. Geological Survey, in cooperation with the Bureau of Reclamation, conducted a study to estimate ground-water use in these counties for 2030 and 2050. This report (1) describes the methods used to estimate ground-water use for the years 2030 and 2050 for six Minnesota counties: Becker, Clay, Douglas, Grant, Otter Tail, and Wilkin Counties, (2) presents the estimated domestic, commercial, industrial, and irrigation ground-water use for the years 2030 and 2050 for these six counties, and (3) compares the estimated ground-water use with published estimates of recharge to three surficial aquifers: Buffalo, Otter Tail surficial, and Pelican River sand plain. Between 74 and 82 percent of the reported ground-water use in the 6 years from 2000 to 2005 was used for irrigation of major crops. The next major use of ground-water was public water supply for domestic use, between 13 and 19 percent of the reported ground-water use. Together they account for 90 to 95 percent of the appropriated ground water in the 6-year period. The total estimated 2030 ground-water use for the six counties ranges from 27,826–36,177 million gallons per year (Mgal/yr), and the total estimated 2050 ground-water use ranges from 31,313–41,746 Mgal/yr. The estimated recharge to the Buffalo aquifer, Otter Tail surficial aquifer, and Pelican River sand-plain aquifer is 3,707, 51,000, and 4,900–8,900 Mgal/yr, respectively. The range of the estimated 2050 ground-water withdrawals from the Buffalo, Otter Tail surficial, and Pelican River sand-plain aquifers is 1,234–1,776 Mgal/yr from the Buffalo aquifer, 11,728–14,820 Mgal/yr from the Otter Tail surficial aquifer, and 3,385–4,298 Mgal/yr from the Pelican River sand-plain aquifer.

Minnesota↗
USGS1970

Ground-water resources of Nelson County, northeastern North Dakota

This investigation is part of a Statewide program to determine the location and extent of the ground-water reservoirs (aquifers); to evaluate the occurrence and movement of ground water within these aquifers, including the sources of recharge and discharge; and to determine the chemical quality of the ground water. Nelson County covers an area of approximately 1,000 square miles in northeastern North Dakota. The study, which began in July 1967, has been made cooperatively by the U.S. Geological Survey, the North Dakota State Water Commission, the North Dakota Geological Survey, and the Nelson County Water Management District. The final results of the study will be published in three parts by the cooperating State agencies.

Hydrologic Atlas↗
USGS1995

Water-resources data for the Fort Berthold Indian Reservation, west-central North Dakota

A study of the water resources of the Fort Berthold Indian Reservation was undertaken to characterize the quality and quantity of ground-water and surface-water resources. The purpose of this report is to document the data-collection procedures used during the study and to present the data collected in tabular and graphical form. Ground-water data were collected during May 1990 through November 1992. The data presented in this report include records of 1,325 wells, test holes, and springs; water-levels fcr 40 observation wells; drillers' logs for 211 wells and test holes; gamma-ray and resistivity logs for 21 test holes drilled in June 1992; water-quality data for 293 water samples from wells ani springs; and trace-element data for 225 water samples from wells. Surface-water data were collected on Bear Den Creek, East Fork Shell Creek, Deepwater Creek, Moccasin Creek, and Squaw Creek from April 1990 through September 1992. Initial!}', five miscellaneous measurement sites were established so that discharge data, selected physical properties of water, and water samples for water-quality analysis could be collected. Gravity data were collected over parts of the Fort Berthold Indian Reservation. As part of the gravity survey, positional data were acquired using global positioning satellite technology.

Open-File Report↗
USGS1972

Ground-water resources of Benson and Pierce Counties, north-central North Dakota

The purpose of this investigation is to provide information about the ground-water resources in Benson and Pierce Counties that is sufficient for planning the safe and intelligent development of water supplies for irrigation, domestic, stock, industrial, and municipal purposes. The investigation is part of a statewide program to determine the location and extent of ground-water aquifers; to evaluate the occurrence and movement of ground water within the aquifers, including sources of recharge and discharge; to determine potential yields to wells developed in the aquifers; and to determine the chemical quality of ground water. Benson and Pierce Counties cover an area of 2,512 square miles in north-central North Dakota. This study, which began in July 1967 and was completed in June 1971, was made cooperatively by the U.S. Geological Survey, the North Dakota State Water Commission, the North Dakota Geological Survey, and the Benson and Pierce Counties Water Management Districts. This interim report presents only the major conclusions of the study.

North Dakota↗
USGS1997

Ground-water sampling methods and quality-control data for the Red River of the North basin, Minnesota, North Dakota, and South Dakota, 1993-95

Ground-water-quality samples were collected for the intensive data-collection phase of the Red River of the P Torth Basin study unit, one of 60 study units of the National Water Quality Assessment (NAWQA) Program throughout the United States. The sampling protocols used were designed for the NAWQA Program. The protocols include sampling equipment, cleaning procedures, sample-collection methods, and quality-control plans to monitor the accuracy of the data collected. One of the goals of the NAWQA Program was to collect data using similar methcds to build a nationally consistent water-quality data base. Quality-control data demonstrated that most constituents measured for this study yielded reproducible data, with low to undetectable contamination from the sampling and analytical procedures. Several constituents were occasionally or frequently detected in blank samples at levels similar to low-concentration ground-water-quality samples. For example, iron was detected in 75 percent of the blank samples, with a maximum concentration of 27 [ig/L, indicating that iron contamination may interfere with its determination at low levels in ground waters. Copper, aluminum, and dissolved organic carbon concentrations in blank samples overlap those determined in ground-waterquality samples, thereby precluding quantitative reporting of those constituents. Most pesticide data are reproducible, with minimal bias. Some pesticides had low but consistent recoveries; these data may be useful if spike and surrogate data are carefully considered. Data for some pesticides measured in this study should not be quantitatively reported or used, because they may underestimate the concentrations of those pesticides in ground waters.

Minnesota, North Dakota, South Dakota↗
USGS2004

River gain and loss studies for the Red River of the North Basin, North Dakota and Minnesota

The Dakota Water Resources Act passed by the U.S. Congress in 2000 authorized the Secretary of the Interior to conduct a comprehensive study of future water-quantity and -quality needs of the Red River of the North (Red River) Basin in North Dakota and of possible options to meet those water needs. To obtain the river gain and loss information needed to properly account for available streamflow within the basin, available river gain and loss studies for the Sheyenne, Turtle, Forest, and Park Rivers in North Dakota and the Wild Rice, Sand Hill, Clearwater, South Branch Buffalo, and Otter Tail Rivers in Minnesota were reviewed. Ground-water discharges for the Sheyenne River in a reach between Lisbon and Kindred, N. Dak., were about 28.8 cubic feet per second in 1963 and about 45.0 cubic feet per second in 1986. Estimated monthly net evaporation losses for additional flows to the Sheyenne River from the Missouri River ranged from 1.4 cubic feet per second in 1963 to 51.0 cubic feet per second in 1976. Maximum water losses for a reach between Harvey and West Fargo, N. Dak., for 1956-96 ranged from about 161 cubic feet per second for 1976 to about 248 cubic feet per second for 1977. Streamflow gains of 1 to 1.5 cubic feet per second per mile were estimated for the Wild Rice, Sand Hill, and Clearwater Rivers in Minnesota. The average ground-water discharge for a 5.2-mile reach of the Otter Tail River in Minnesota was about 14.1 cubic feet per second in August 1994. The same reach lost about 14.1 cubic feet per second between February 1994 and June 1994 and about 21.2 cubic feet per second between August 1994 and August 1995.

Open-File Report↗
USGS1997

Digital simulation of ground-water flow in the Warwick Aquifer, Fort Totten Indian Reservation, North Dakota

The demand for water from the Warwick aquifer, which underlies the Fort Totten Indian Reservation in northeastern North Dakota, has been increasing during recent years. Therefore, the Spirit Lake Sioux Nation is interested in resolving questions about the quantity and quality of water in the aquifer and in developing a water-management plan for future water use. A study was conducted to evaluate the surface-water and ground-water resources of the Fort Totten Indian Reservation and, in particular, the ground-water resources in the area of the Warwick aquifer. A major component of the study, addressed by this report, was to define the ground-water flow system of the aquifer. The Warwick aquifer consists of outwash deposits of the Warwick outwash plain that are as much as 30 feet thick and buried-valley deposits beneath the outwash plain that are as much as 200 feet thick. The aquifer is bounded on the north and west by end-moraine deposits and Devils Lake, on the south by the Sheyenne River Valley, and on the east by outwash deposits and ravines. The aquifer is underlain by Pierre Shale or by glacial till, clay, or silt. Ground-water gradients generally are small and rarely are more than 3 or 4 feet per mile. From 1982 to 1993, withdrawals from the Devils Lake well field averaged 1.5 cubic feet per second, and withdrawals from irrigation wells averaged 1.29 cubic feet per second. The combined discharge from springs may be about 3 cubic feet per second. During the early 1990s, the Warwick aquifer probably was in a steady-state condition with regard to storage change in the aquifer. A finite-difference, three-dimensional, ground-water flow model provided a reasonable simulation of ground-water flow in the Warwick aquifer. The aquifer was divided vertically into two layers and horizontally into a grid of 83 by 109 cells, each measuring 656 feet (200 meters) per side. The steady-state simulation was conducted using 1992 pumpage rates and October 1992 water levels. The mean absolute difference between simulated and derived water-level altitudes during final calibration of the model was 1.52 feet. The two transient simulations were conducted for 20 time intervals of 1 year each using both the small and large storage estimates, doubled 1992 pumpage from the Devils Lake well field, 1992 irrigation pumpage, and initial water-level altitudes simulated by the October 1992 steady-state simulation. In the simulation using the small storage estimate and doubled pumpage, model cells in the area of the well field went dry after 13 years. Assumptions made in the design of the model generally are supported by the digital simulation. Except in the area of Warwick Springs and smaller springs, lateral and basal boundaries of the aquifer are impermeable. The flow system is dominated by recharge and evapotranspiration. Recharge rates obtained during the calibration process were lower in topographically high areas than in topographically low areas. Hydraulic conductivity in the area of the Devils Lake well field was larger than that in the rest of the aquifer.

Water-Resources Investigations Report↗
USGS1987

Hydrology and chemistry of selected prairie wetlands in the Cottonwood Lake area, Stutsman County, North Dakota, 1979-82

The relation of hydrologic setting and temporal variability in hydrology to nutrient content and geochemical characteristics of a group of prairie wetlands and adjacent ground water was studied during the period 1979-82. Although data were collected from many wetlands and wells at the study site, emphasis in this report primarily is on four wetlands two seasonal and two semipermanent and four wells contiguous to them along a hydrologic section. The seasonal wetlands, T8 and T3, contained water only for a few weeks to months after filling in spring and early summer; both were completely dry by August. The semipermanent wetlands, PI and P8, contained water throughout each year and were ice covered in winter. One wetland, T8, recharges ground water. Wetlands PI and P8 are in areas of ground-water discharge. None of the wetlands received water by channelized surface-water inlets. Only wetland P8 had a channelized surface-water outlet. Ground-water-level data showed that high points of the water table did not always occur beneath land-surface highs. Reversals of ground-water flow occurred occasionally between two of the wetlands, T3 and PI. Significant differences existed in the chemical composition of the wetlands based on their hydrologic setting. In general, the dominant cation and anion in the wetlands were potassium and bicarbonate in wetland T8, calcium and sulfate in wetland T3, magnesium and sulfate in wetland PI, and magnesium and bicarbonate in wetland P8. Significant seasonal differences existed in the water chemistry of the wetlands in ground-water discharge areas. Water in three of the wetlands, T3, Pi, and P8, was most dilute while they filled in spring after icemelt. Concentration increased during the open-water period, and two of the wetlands, PI and P8, became most concentrated under ice cover. Concentrations of total phosphorus and total nitrogen were greatest in wetlands in areas of ground-water recharge and least in wetlands in areas of ground-water discharge. Differences in the chemistry of water from wells in the adjacent ground water resulted primarily from the positions of the wells in the ground-water flow system. The chemical type of water from well 12, which was located in a ground-water recharge area, was calcium sodium bicarbonate. Water from well 4, located downgradient from wetland T8, and from well 16, located downgradient from wetland PI, typically was a calcium sulfate type. Water from well 13, located between wetlands T3 and PI in an area of changing ground-water flow directions, was a magnesium sulfate type. Data from this study show that an understanding of hydrologic conditions is important in the interpretation of the water chemistry of wetlands in the study area.

Professional Paper↗
USGS1950

Progress report on the geology and ground-water hydrology of part of the Oahe Unit, James River Division, South Dakota

The Oahe Unit, in the James River basin in eastern South Dakota, extends for about 100 miles north and south and is 20 to 80 miles wide, having the river as its east border. The Oahe irrigation project is planned to supply water to 750,000 to 1,500,000 acres of the most suitable land within the area. The studies that have been undertaken in the Oahe area by the Ground Water Division of the U. S. Geological Survey form a part of the investigations which are being carried on by several bureaus of the Department of the Interior and other government agencies for the conservation, control and utilization of the water resources of the Missouri River Basin. The field studies on which the present report is based were made during May 1947 through November 1948 and cover about 1,890 square miles in the southern part of the Oahe area. Data were collected on the character of the surficial geological deposits, and on the occurrence, movement, quantity, and quality of the groundwater supplies. The report describes the several water-bearing formations and presents nine typical logs of deep artesian wells. The records of fluctuation of the water table in 168 wells in or near the Oahe area are listed. Tabulated inventory of 3,257 wells and springs includes information on the observation wells and on all other wells that were noted within the area examined.

South Dakota↗
USGS1989

Geochemistry of artificial-recharge tests in the Oakes aquifer near Oakes, southeastern North Dakota

As part of an artificial-recharge feasibility study, water from the James River was introduced into the Oakes aquifer of southeastern North Dakota by infiltration through a recharge basin. Chemical composition of water in the recharge basin and ground water from two separate flow paths beneath the basin was determined from samples taken during two artificial-recharge tests. Changes between recharge-basin water and ground water from the termination of the flow paths during the spring 1987 test included increases in alkalinity, calcium, sodium, and silica and decreases in pH and dissolved oxygen. Interpretation of processes modifying the chemical composition of recharge water was complicated by mixing of recharge water with pre-existing ground water within the Oakes aquifer. In the summer 1987 test, the recharge basin was lined with a decomposing organic mat. The purpose of the organic mat was to sustain large infiltration rates for a longer period of time and to evaluate the effect of a decomposing organic mat on water quality during sustained recharge-basin operation. Larger infiltration rates with the organic mat in place allowed recharge water to reach the termination of the flow paths prior to apparent mixing with pre-existing ground water for a period of as much as approximately 405 hours of recharge-basin operation. Changes between recharge-basin water and ground water from the termination of the flow paths during the summer 1987 organic-mat test included increases in alkalinity, calcium, and silica and decreases in pH, dissolved oxygen, and total organic carbon. Detected changes between recharge-basin water and ground water from the termination of the flow paths were interpreted using a mass-balance geochemical model. Chemical changes of at least 2 milligrams per liter were modeled in terms of reactions, including those due to respiration of micro-organisms, dissolution of carbon dioxide, possible production of organic acids, dissolution of amorphous silica, cation exchange, and dissolution of carbonate minerals. Generation of organic acids within the decomposing organic mat may cause dissolution of dolomite in the subsurface.

Water-Resources Investigations Report↗
USGS1981

Characteristics of central North Dakota wetlands determined from sample aerial photographs and ground study

Wetland characteristics were assessed from a systematic sample of 66 plots, 3.22 km2 each, drawn from a 10,041-km2 study area in central North Dakota. Each plot was visited once and 8 sets of aerial photographs were obtained in 3 years. Density of wetland basins was 11.00 ha/km2, and area averaged 9.7 ha/km2. Seasonal and temporary wetlands were most abundant; semipermanent wetlands occupied the greatest area. Basin size was positively correlated with water permanence. Discriminant function analysis based on size and an index to wetness derived from photographs misclassified 33% of the wetland basins. Forty percent of the wetlands were tilled. Photography of sample plots is potentially useful for determining number of basins and wetland area, but precise classification of plant communities in this region would require ground study.

Wildlife Society Bulletin↗
USGS2007

The concept of hydrologic landscapes

Hydrologic landscapes are multiples or variations of fundamental hydrologic landscape units. A fundamental hydrologic landscape unit is defined on the basis of land-surface form, geology, and climate. The basic land-surface form of a fundamental hydrologic landscape unit is an upland separated from a lowland by an intervening steeper slope. Fundamental hydrologic landscape units have a complete hydrologic system consisting of surface runoff, ground-water flow, and interaction with atmospheric water. By describing actual landscapes in terms of land-surface slope, hydraulic properties of soils and geologic framework, and the difference between precipitation and evapotranspiration, the hydrologic system of actual landscapes can be conceptualized in a uniform way. This conceptual framework can then be the foundation for design of studies and data networks, syntheses of information on local to national scales, and comparison of process research across small study units in a variety of settings. The Crow Wing River watershed in central Minnesota is used as an example of evaluating stream discharge in the context of hydrologic landscapes. Lake-research watersheds in Wisconsin, Minnesota, North Dakota, and Nebraska are used as an example of using the hydrologic-landscapes concept to evaluate the effect of ground water on the degree of mineralization and major-ion chemistry of lakes that lie within ground-water flow systems.

Minnesota, Nebraska, North Dakota, Wisconsin↗
USGS2005

The use of principal component analysis for interpreting ground water hydrographs

Principal component analysis was used to define patterns in water table hydrographs at four small, lake-watershed research sites in the United States. The analysis provided insights into (1) characteristics of ground water recharge in different parts of the watersheds; (2) the effect of seepage from lakes on water table fluctuations; and (3) the effect of differences in geologic properties on water table fluctuations. At two sites where all of the water table wells were completed in permeable deposits, glacial out-wash in Minnesota and dune sand in Nebraska, the patterns of water table fluctuation primarily reflected timing and magnitude of recharge. The water table had more frequent and wider ranges in fluctuations where it was shallow compared with where it was deep. At two sites where the water table wells were completed in sand or till, a glaciated mountain valley in New Hampshire and stagnation moraine in North Dakota, the patterns of water table fluctuations were strongly related to the type of geologic unit in which the wells are completed. Furthermore, at the New Hampshire site, the patterns of water table fluctuations were clearly different for wells completed in sand downgradient of a lake compared with those completed in sandy terraces on a mountainside. The study indicates that principal component analysis would be particularly useful for summarizing large data sets for the purpose of selecting index wells for long-term monitoring, which would greatly reduce the cost of monitoring programs.Principal component analysis was used to define patterns in water table hydrographs at four small, lake-watershed research sites in the United States. The analysis provided insights into (1) characteristics of ground water recharge in different parts of the watersheds; (2) the effect of seepage from lakes on water table fluctuations; and (3) the effect of differences in geologic properties on water table fluctuations. At two sites where all of the water table wells were completed in permeable deposits, glacial outwash in Minnesota and dune sand in Nebraska, the patterns of water table fluctuation primarily reflected timing and magnitude of recharge. The water table had more frequent and wider ranges in fluctuations where it was shallow compared with where it was deep. At two sites where the water table wells were completed in sand or till, a glaciated mountain valley in New Hampshire and stagnation-moraine in North Dakota, the patterns of water table fluctuations were strongly related to the type of geologic unit in which the wells are completed. Furthermore, at the New Hampshire site, the patterns of water table fluctuations were clearly different for wells completed in sand downgradient of a lake compared with those completed in sandy terraces on a mountainside. The study indicates that principal component analysis would be particularly useful for summarizing large data sets for the purpose of selecting index wells for long-term monitoring, which would greatly reduce the cost of monitoring programs.

New Hampshire, Minnesota, Nebraska, North Dakota↗
USGS1979

Plan of study for the northern Great Plains regional aquifer-system analysis in parts of Montana, North Dakota, South Dakota, and Wyoming

The Northern Great Plains, an area of about 250,000 square miles in parts of Montana, North Dakota, South Dakota, and Wyoming, is underlain by an accumulation of sediments eroded from the Black Hills and from mountains to the west. Principal aquifers are areally extensive beds of sandstone within these sedimentary rocks, some at great depths. Anticipated future water needs dictate that available ground-water supplies be evaluated for management of this natural resource. The U.S. Geological Survey has started (1978) a 4-year study of the Northern Great Plains aquifer system. The objective of this study is to define availability and quality of ground water and to predict the effects of using this resource. To achieve this objective, the ground-water system will be described in terms of spatial distribution, hydraulics, geology, and geochemistry. Once described, the ground-water system will be simulated by mathematical models that will be used to define responses of the system to various management alternatives and assumed development patterns.

Montana, North Dakota, South Dakota, Wyoming↗
USGS1991

Relation of nitrate concentrations in water to agricultural land use and soil type in Dakota County, Minnesota, 1990

The quality of surface and ground water can be related to various physical factors such as land use, soil type, geology, and depth to water table. Land use in Dakota County, Minnesota, is changing: urbanization and industrialization in the north and increasing irrigation and application of agricultural chemicals in the central part of the county. The U.S. Geological Survey, in cooperation with the Minnesota Department of Natural Resources, the Legislative Commission on Minnesota Resources, and the Dakota County Soil and Water Conservation District, is studying the relations between some physical factors and the quality of surface-and ground-water in Dakota County. The findings of the study can be used by local officials involved in land-use planning and management. Nitrate is commonly found in ground water in agricultural areas throughout the Midwest. The emphasis of this report is to relate differences in nitrate concentrations in ground water to agricultural land use and soil type. In addition, nitrate concentrations in streams, shallow ground water near the water table, and deeper ground water from 10 to 30 feet below the water table are tabulated for selected sites in Dakota County.

Minnesota↗
USGS1974

Preliminary map showing availability of ground water from major glacial-drift aquifers in Griggs and Steele Counties, North Dakota

This investigation is part of a statewide program to determine the location, extent, and hydrologic characteristics of the ground-water reservoirs (aquifers). The investigation was made cooperatively by the U.S. Geological Survey, North Dakota State Water Commission, North Dakota Geological Survey, and Griggs and Steele Counties Water Management Districts. This preliminary map is the first product of an intensive study of Griggs and Steele Counties. A well inventory provided data on depth, construction, and productivity of private and public wells. Test drilling by the North Dakota State Water Commission, Federal agencies, and commercial well drillers provided information regarding the thickness, grain size, and extent of the aquifers. Potential well yields were estimated from the thickness and hydraulic conductivity of the water-bearing materials logged at each test hole, and from aquifer tests. Generally, the yield of a well is proportional to the hydraulic conductivity and thickness of the aquifer.

North Dakota↗