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Research about Otter Tail County, Minnesota

Source-linked reports with geographic coverage including Otter Tail County, Minnesota.

6 recordsLinked to original sources
USGS1995

Presence and distribution of nitrate and selected pesticides in surficial-sand aquifers and selected lakes, 1993-94, East Otter Tail County, Minnesota

This report presents selected data collected during the first year (December 1993 to September 1994) of a three year water-quality study of surficial-sand aquifers and selected lakes in east Otter Tail County, Minnesota. The objectives of the study are (1) to determine the presence and distribution of nitrate-nitrogen and selected pesticides in ground water from the surficial-sand aquifers; and (2) to characterize the water quality of selected lakes and the Otter Tail River. Ground water was sampled from 73 wells. The concentration of nitrate nitrogen in ground water was above 10 mg/L (milligrams per liter) in 30 of the sampled wells (38 percent). The concentration of triazine herbicide compounds, as determined by immunoassay, was above the detection limit 0.10 ug/l (micrograms per liter) in water from 17 of the sampled wells (24 percent). The nitrate- nitrogen concentration in water from 14 wells, compared to data collected during a previous study in 1979-81, increased in water from 4 wells and decreased in water from 4 wells. Lake water was sampled from 11 sites on Little Pine, Big Pine, Rush, and Otter Tail Lakes. Nitrate-nitrogen concentrations were all below the detection limit (0.05 mg/L). The concentration of triazine herbicide compounds, as determined by immunoassay, was at or below the detection limit (0.10 ug/L) at all 11 sites. Dissolved oxygen concentrations at the sites ranged from 7.3 to 10.1 mg/L at the water surface, and from 5.3 to 9.7 mg/L at depth. Secchi disk transparency readings ranged from 4.0 to 7.4 feet. Total phosphorus concentrations were generally near or below the detection limit (0.01 mg/L) except at one site where the water had a total phosphorus concentration of 0.06 mg/L.

Minnesota↗
USGS1987

Water-quality data for Orwell reservoir and the Otter Tail River near Fergus Falls, Minnesota

Water-quality data were collected at five sites on Orwell Reservoir and two sites on the Otter Tail River, at the inflow and outflow points of the reservoir. The data, collected from April 1983 to July 1966, consist mainly of streamflow and nutrient concentrations at the river sites and nutrient concentrations, alkalinity, Secchi-disk transparency, phytoplankton counts, chlorophyll concentrations, and profiles of specific conductance, temperature, pU, and dissolved oxygen at the reservoir sites. Additional data collected at the outflow site include alkalinity and concentrations of major ions and organic carbon.

Minnesota↗
USGS1972

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.

Minnesota↗