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L. C. Trotta

Publications and source records attributed to L. C. Trotta.

11 recordsLinked to original sources
USGS1998

Ground water resources of the Mille Lacs Lake area, east-central Minnesota

The Mille Lacs Lake study area is a 960 mi 2 area containing the ground-water and surface-water drainages to both Mille Lacs Lake and the first 12 miles of the Rum River. Within this study area, available ground water occurs in saturated, overlapping, discontinuous, partially-connected, glacially-deposited (hereinafter, glacial) aquifers and in bedrock aquifers. No extensive glacial aquifer could be delineated. Surficial aquifers generally are less than 30 feet thick, but may exceed 78 feet. Lake Onamia is hydraulically connected with surficial aquifers on its north and south sides. Ground water enters Lake Onamia from an adjacent surficial aquifer with a hydraulic head of 1.56 feet near its eastern shore. Glacial aquifers buried beneath till form the uppermost confined (hereinafter, buried) aquifers and generally are from 3 to 15 feet thick, but may be as much as 118 feet thick. These buried aquifers generally occur beneath 10 to 60 feet of till and clay, but it may be as thick as 208 feet. Individual aquifers can be partially buried by till and therefore may contain surficial and buried areas. Most buried aquifers are isolated or only partially connected to other aquifers. Recharge water moves horizontally and vertically through other aquifers and through confining units to reach these buried aquifers. Discharge from these aquifers is through well withdrawals, flow to surface-water bodies, and leakage to other aquifers. Buried aquifers may yield as much as 500 gallons per minute in some locations. In most areas, the specific capacity of these aquifers is less than 1 gallon per minute per foot but may reach 41.6 gallons per minute per foot. Ground water from all aquifers is of the calcium magnesium bicarbonate type. Iron, manganese, and sodium in this ground water frequently exceeded U.S. Environmental Protection Agency drinking water standards and health advisories. The sodium health advisory was exceeded in 15 percent of samples.

Minnesota↗
USGS1995

Withdrawal and delivery of water by municipal supplies in Minnesota, 1993

Total withdrawal Statewide by municipal suppliers serving over 1,000 people was 108 billion gallons in 1993. Most of Minnesota's municipal deliveries were for residential purposes. About 87 percent of suppliers withdraw from ground-water and 13 percent withdraw from surface-water sources. Water withdrawn for public supply has steadily risen since 1955 and the increase has mainly come from ground water. Declines in per capita use since 1990 may be related to heavy rainfall, conservation measures, and the installation of more efficient water-using machines.

Minnesota↗
USGS1990

Importance of return flow as a component of water use

Understanding the relation between the hydrologjc cycle and water use is important for effective water-resources management. The hydrologic cycle is the natural pathway of water from evaporation to precipitation to infiltration or runoff and to storage from which evaporation can again occur. The science of water use is the study of human influences on the hydrologic cycle. Human activities affect the hydrologic cycle by changing the quantity, distribution, and quality of available water. Quantifying return flow is useful to water managers in evaluating such changes. Return flow is often thought of as what runs down the drain, or what is leftover after the water's purpose has been served. As innocuous as that may sound, return flow plays a significant part in the overall water-use picture.

Minnesota↗
USGS1988

Water use for aquaculture in Minnesota, 1984

Aquaculture supports a large sportfishing industry in Minnesota. Licensed fish farms that hatch and (or) harvest minnows or gamefish are located throughout the State. The volume of water used in these operations can be expressed as the minimum capacity per pound of fish, total water consumed, total water dedicated to the farming operation, or total water withdrawn. In expressing water dedicated to the farming operation, the total surface area of water bodies dedicated to aquaculture in Minnesota in 1984 was about 141,500 acres, based on interpretation of data reported in license applications. Water withdrawals to fish holding tanks amounted to 0.73 million gallons per day in 1984. Water-use calculations address the possibility of errors in reporting. About 15 percent of the licensees use municipally supplied water for their holding tanks. One thermoelectric powerplant recently began reusing the heated water from its cooling towers to raise catfish. Little change in the number of licensees since 1980 -indicates that aquaculture is a viable segment of the Minnesota economy. Trout farming has grown from 10 farms in 1978, to 23 in 1984; most use dug ponds sustained by ground-water inflow. Withdrawals for aquaculture are nonconsumptive and are small compared to other water-use categories in Minnesota.

Minnesota↗
USGS1978

Ground-water resources and geology of Columbia County, Wisconsin

The increasing need for water of good Quality in Columbia County, caused by a steadily increasing population, can be met from the sand-and-gravel and sandstone aquifers. As much as 15 gallons per minute can be obtained from wells almost everywhere. Yields of more than 1,000 gallons per minute are available from drift where it contains a sufficient thickness of saturated sand and gravel (the sand-and-gravel aquifer). The sandstone aquifer underlies nearly all the county except for areas west of the Wisconsin River and northwest of Pardeeville. It is more than 700 feet thick in the south-central part. The sandstone aquifer includes all bedrock younger than Precambrian age and is capable of yielding more than 1,000 gallons per minute to wells in about three-fourths of the county. It is the principal source of municipal-water supply. The chemical quality of water from the two aquifers is similar. It is very hard (mean concentration of about 300 milligrams per liter as calcium carbonate), and much of it contains excessive amounts of iron and manganese. Concentrations of dissolved solids and chloride are higher in areas underlain by bedrock of Ordovician age than elsewhere. About 5.0 million gallons per day of water was pumped in the county in 1974, 90 percent from the sandstone aQuifer. About 45 percent of the total water pumped was for industrial and commercial purposes~ 37 percent was for residential use, 16 percent for municipal use, and 2 percent for irrigation.

Wisconsin↗
USGS1975

Ground-water resources and geology of Jefferson County, Wisconsin

A steadily increasing population in Jefferson County, Wisconsin, is expanding the need for good-quality ground water. This need can be met by good-quality water available from the sand-and-gravel, Galena-Platteville, and sandstone aquifers. As much as 15 gallons per minute (0.95 liters per second) can be obtained from wells almost everywhere in the county. Yields of more than 1,000 gallons per minute (63 liters per second) are available from glacial drift where it contains a sufficient thickness of saturated sand and gravel. The Galena-Platteville aquifer is a dolomite that occurs mainly in the eastern one-half of the county and is locally more than 300 feet (90 meters) thick. Estimated well yields from this aquifer exceed 500 gallons per minute (32 liters per second). The sandstone aquifer underlies nearly the entire county except for small areas in the northwest corner. It is more than 1,100 feet (330 meters) thick in the southwest along the Dane-Jefferson County line. This aquifer is capable of yielding more than 1,000 gallons per minute (63 liters per second) to wells in much of the county and is the principal source of municipal water. The chemical quality of water from the three aquifers is similar. The water is very hard, having a median hardness between 315 and 325 milligrams per liter. Median values for dissolved solids range between 325 and 349 milligrams per liter. Iron and manganese commonly are present in bothersome amounts (combined total exceeding 0.3 milligrams per liter. About 13.0 million gallons per day (0.570 cubic meters per second) of ground water was pumped in the county in 1972, 87 percent from the sandstone aquifer. About 62 percent of the total water pumped was for industrial and commercial purposes, 26 percent for residential use, and 12 percent for municipal, irrigation, and institutional use.

Wisconsin↗