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Research about Minnesota

Source-linked reports with geographic coverage including Minnesota.

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Water resources of the Crow Wing River watershed, central Minnesota

The Crow Wing River, a tributary of the Mississippi River, drains an area of about 3,760 square miles, essentially all of which is covered by glacial deposits. Topography of most of the watershed is slightly- to moderately-undulating and has local relief of up to about 50 feet. The margin of the watershed, particularly the southwestern and northwestern parts, is higher and has local relief often exceeding 150 feet. The higher areas contain numerous lakes and, in the extreme north and east parts of the watershed, are heavily forested.

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Water resources of the Minnesota River-Hawk Creek watershed, southwestern Minnesota

The Minnesota River – Hawk Creek watershed is located in southwestern Minnesota. The watershed has an area of 1,479 square miles and is drained along its southwestern edge by the Minnesota River (Minnesota Division of Waters, 1959). The major watercourse within the watershed is Hawk Creek, having a drainage area of 510 square miles. Other, shorter streams drain into the Minnesota River but are mostly ephemeral. The watershed has a gently undulating land surface formed on glacial deposits. Directly underlying the glacial deposits in most of the area are Cretaceous sedimentary rocks. Paleozoic and Precambrian rocks are also locally in contact with overlying glacial deposits. Beds of sand and gravel buried at various depths within the glacial deposits are generally thin and discomtinuous but are the most accessible and widely used aquifers in the watershed. Beds of poorly consolidated sandstone in the Cretaceous rocks are locally good aquifers, generally yielding softer water, but in lesser quantities, than aquifers in the overlying glacial deposits. In the eastern part of the watershed, aquifers in Paleozoic and Precambrian sedimentary rocks are capable of high yields to wells and contain water of similar quality to water in the overlying Cretaceous and glacial deposits.

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Availability of ground water for irrigation from glacial outwash in the Perham area, Otter Tail County, Minnesota

The Perham study area includes about 350 square miles of surficial deposits of glacial outwash in the central part of Otter Tail County in west-central Minnesota. The aquifer characteristics have a wide range, as follows: Transmissivity values range from nearly 0 along the perimeter of the area to more than 100,000 gallons per day per foot in the central parts of the area; storage coefficient values range from 0.1 to 0.2; and the saturated thickness of the upper outwash material ranges from nearly 0 to more than 100 feet. Most of the aquifer material is fairly well sorted and is in the particle-size range of fine to coarse sand. Wells penetrating the full thickness of the aquifer and developed to 100 percent efficiency can be expected to yield 1,200 gallons per minute for 30 days and to have drawdowns of less than two-thirds the aquifer thickness in much of the area; however, well yields vary widely within short distances. Yields of 300 gallons per minute or less can be expected from wells drilled near the edges of the area and in the general area east and southeast of Otter Tail Lake. Results from the mathematical analyses show that the amount of streamflow leaving the area will not be depleted within the 10-year analysis period, if not more than 6 inches of water per year is used on all the irrigable land in the outwash area. If pumpage and its effects on the streams is assumed to be prorated proportionately along the full length of the streams within the area, then the levels of lakes along these streams generally will not be lowered appreciably. However, owing to the heterogeneity of the aquifer and the other variable factors involved, some reaches of the streams may cease to flow when full ground-water development is approached, which, in turn, would result in a decline in some lake levels. Lakes and ponds not connected to streams in the area are expected to be lowered considerably or to be dried up completely as pumping becomes more extensive in years to come. If irrigation wells and other large-yield wells in the study area are spaced 1 mile or more away from streams and lakes, the effect of ground-water pumping on the streams will be small, and the lake levels will be affected very little. However, the lakes and ponds are expected to approach normal levels during periods of above-normal precipitation and during periods of no pumping.

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Ground water for irrigation in the Brooten-Belgrade area, west-central Minnesota

Water for irrigation is needed to improve crop yields from sandy soils in the Brooten-Belgrade area. Ground-water supplies of sufficient quantity and suitable quality for irrigation are available in much of the area. Quaternary glacial drift, as much as 300 feet thick, is underlain by Precambrian crystalline rocks and possibly by Cretaceous sedimentary rocks. Sand and gravel aquifers are buried at various depths in the drift and can be located by test drilling. One buried aquifer, possibly capable of high yields, is within 250 feet of the land surface in the vicinity of Belgrade. Glacial outwash comprises the upper part of the drift in most of the project area and is locally more than 100 feet thick. The outwash is made up of crossbedded sand and gravel that is interbedded in places with silt and clay deposits and has a saturated thickness of as much as 65 feet. Locally, the transmissivity of the surficial aquifer is as much as 60,000 gallons per day per foot, but elsewhere is generally less than 30,000 gallons per day per foot. The aquifer should yield more than 300 gallons per minute and locally more than 1,000 gallons per minute to individual wells in much of the northern and southwestern parts of the area. Recharge to the surficial aquifer is almost entirely from precipitation. Significant ground-water losses occur as base flow and underflow, and through evaporation and transpiration. Water in the buried and surficial aquifers is of the calcium magnesium bicarbonate type and is of suitable quality for irrigation. An analog model, simulating yearly 30-day pumping periods and hypothetical volumes and distributions of withdrawals, showed the effects on the surficial aquifer of withdrawals of about 20,000 acre-feet per pumping season for 20 years. Predicted water-level declines caused by withdrawals of 20,000 acre-feet per pumping season were generally less than 5 feet in the surficial aquifer and years Predicted water-level declines caused by withdrawals of 20,000 acre-feet pumping season caused predicted water-table declines of more than 10 feet in large parts of the area and caused lake-level declines of as much as 8 feet. The model indicated that water removed from aquifer and lake storage accounted for less than 50 percent of all withdrawals; the remainder was accounted for by water recovered from stream base flow and by water diverted from evaporation and transpiration.

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Ground water for irrigation near Lake Emily, Pope County, west-central Minnesota

In the Lake Emily area, thickness of the glacial drift ranges from about 200 feet to more than 400 feet. Within the drift are sand and gravel aquifers, some of which can yield adequate water supplies for irrigation. Outwash, as much as 60 feet thick, lies at the surface. The outwash has saturated thicknesses of more than 40 feet and transmissivities of more than 50,000 gallons per day per foot locally in the northern and western parts of the area. In the places of large saturated thickness and high hydraulic conductivity, the aquifer should yield more than 600 gallons per minute to wells. Theoretical maximum yields to wells in most of the area are more than 100 gallons per minute. Chemically, water in the buried and surficial aquifers is mainly of a calcium magnesium bicarbonate type and is suitable for irrigation. Calculated and estimated sodium adsorption ratios and salinity and boron concentrations are below the limits recommended by the U.S. Department of Agriculture.

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Age of the Morton and Montevideo gneisses and related rocks, southwestern Minnesota

Granitic gneisses in the vicinities of Morton and Montevideo in the Minnesota River Valley are dated at 3550 m.y. ago and are the oldest rocks so far found in North America. The gneisses were altered in varying degree by younger events of which two have been dated at 2650 m.y. and 1850 m.y. old. The event which occurred 2650 m.y. ago was a high-grade metamorphism accompanied by the intrusion of a large volume of granitic magma. Only the U-Pb zircon and the Rb-Sr whole-rock ages survived this event, and both types are discordant. A two-stage model that explains the U-Pb discordant ages combines a primary discordance produced during the metamorphism of 2650 m.y. ago with a secondary discordance developed approximately 100 m.y. ago when uplift and erosion brought the rocks close to the surface. This secondary discordance is also shown by the zircon from granite near Sacred Heart (2650 m.y. old) and from a younger granitic pluton (1850 m.y. old) near Granite Falls. The discordance in the Rb-Sr whole-rock ages is attributed primarily to the loss of radiogenic Sr 87 that probably occurred largely during the metamorphism of 2650 m.y. ago. Some later loss, however, is indicated in the younger ages of biotite and K-feldspar. Granitic material introduced or mobilized during the metamorphism is also a complicating factor. The 1850-m.y.-ago event was a low-grade metamorphism that reset the K-Ar and Rb-Sr ages of biotite in the rocks between Granite Falls and Ortonville. A number of small plutons, ranging in composition from gabbro to granite, and basaltic dikes were emplaced in the gneisses at this time, but only the granitic pluton near Granite Falls has been dated by both U-Pb and Rb-Sr methods. The mineral ages show variations that are difficult to explain, and the low apparent ages of the biotite may be in some way related to epeirogeny and the stabilizing of the K-Ar and Rb-Sr systems. The southeastern part of the valley, underlain by the Morton Gneiss and the granite at Sacred Heart, was stabilized 2400 to 2600 m.y. ago, but the northwestern part, underlain by gneiss in the Granite Falls-Montevideo area and by granite in the Ortonville area, was not stabilized until 1700 to 1850 m.y. ago. The Morton Gneiss was formed by synkine-matic intrusions of trondhjemitic and granitic magmas, and the structure dates back to the time of the intrusions, 3550 m.y. ago. A similar origin as a synkinematic intrusion of granite is favored to explain the gneiss at Montevideo. The country rock appears to have been a layered series of basaltic lavas, sedimentary rocks, and possibly some sill-like masses of diabase or gabbro. The structure of the region probably was considerably modified during the high-grade metamorphism 2650 m.y. ago. The rock types that were involved in the Mortonian event 3550 m.y. ago are similar to more recent crustal rocks and do not represent a protocrust.

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Water resources of the Wild Rice River watershed, northwestern Minnesota

The Wild Rice watershed includes two general physiographic areas- the glacial Lake Agassiz Plain and a glacial moraine. The lake plain is extremely flat in the western part, sloping only a few feet per mile, but in the eastern part the plain is traversed in a north-south direction by long, narrow beach ridges up to 20 feet high. The moraine is an area of hills and depressions. The local relief is low in the western part of the moraine but increases to more than 200 feet in the east. Altitude of the land surface ranges from 800 feet above mean sea level where the Red River flows north out of the area to 2,040 feet near the southeastern edge of the watershed (one of the highest points in Minnesota). The area of the watershed is about 2,600 square miles and includes most of Mahnomen and Norman Counties and parts of Becker, Clay, Clearwater, and Polk Counties. The population of the area is about 37,000 people of which about 70 percent live on farms. The economy is based principally on farming. The area of lake clay and silt is used mostly for raising sugar beets and wheat; and potatoes are grown largely on the sandy soils. In the western part of the morainal area small grain, dairy, and cattle farming is the most common. The eastern part of the morainal area is important for forest products and recreation. Industries in the area are small and are based on agricultural processing and service.

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Water resources of the Redwood River watershed, southwestern Minnesota

The Redwood River watershed contains 739 square miles underlain by glacial drift and sedimentary and crystalline rocks. The land surface slopes gently northeastward and eastward from altitudes greater than 1900 feet at the southwestern edge to less than 850 feet at the mouth of the Redwood River in the east. The area has slight local relief shaped by continental glaciation. The Redwood River and its tributaries, many of which are ephemeral, and ponds and lakes in the area provide water for local use and habitat for wildlife. The glacial drift and sedimentary rocks yield generally adequate water supplies for municipalities, households, and farms.

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