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R.F. Norvitch

Publications and source records attributed to R.F. Norvitch.

8 recordsLinked to original sources
USGS1984

Ground-water-level trends in Idaho, 1971-82

Water-level trends, net water-level changes, and major causes governing these water-level fluctuations are presented for 366 wells in the Idaho statewide observation-well network. Water-level trends were determined for 293 wells. Downward trends in 176 of these wells ranged from less than 1 foot per year to a maximum of 7 feet per year; upward trends in 90 wells ranged from less than 1 foot per year to a maximum of 6 feet per year. Trends were level (no change) in 27 wells. Net water-level changes were determined for 361 wells. Net declines in 269 of these wells ranged from less than 1 foot to a maximum of 52.65 feet; net rises in 92 wells ranged from less than 1 foot to a maximum of 25.12 feet. Significant net water-level declines and downward trends were most apparent in or near areas designated as critical ground-water areas by the Idaho Department of Water Resources. (USGS)

Idaho↗
USGS1973

Water resources outlook for the Minneapolis-Saint Paul Metropolitan Area, Minnesota

The water resources were studied within an area whose natural ground-water flow is largely towards the center of the metropolitan area. This area coincides with the extent of the Hinckley Sandstone aquifer. Thus, the general geohydrology of the area bounded by the extent of the Hinckley Sandstone (about 6,000 square miles) as it relates to the hydrology of the Minneapolis-St. Paul metropolitan area is described. Greater emphasis is placed on the area underlain by the Prairie du Chien-Jordan aquifer (about 2,000 square miles), from which approximately 75 percent of the ground-water for the metropolitan area is pumped. The study indicates that the surface-water resources of the Twin Cities metropolitan area are used to such an extent that a supply adequate for domestic and industrial needs as well as power plant and sanitary effluent assimilation will not be available during severe drought. Ground-water is obtained primarily from two aquifer systems: The Prairie du Chien-Jordan and the Mount Simon-Hinckley. In 1970, these aquifers supplied about 90 percent (175 mgd) of the ground-water used in the metropolitan part of the study area. The probable level of development that can be sustained by these two aquifers in the metropolitan area is estimated to be 1,100 mgd; thus, substantial additional ground-water supplies could be developed. However, considerable management and planning would be needed to sustain this level of development. Maps in this report can be used to select general well-field locations based on consideration of 1) aquifer, 2) depth needed for completion, 3) head availability, 4) location of natural recharge and discharge boundaries, and 5) distance from areas where over-development of ground-water resources is imminent. Because of complexities in the ground-water system, yield estimates, boundary effects, and effects of aquifer interaction may best be determined in a study incorporating the use of a hydrologic model. Future detailed studies might include elaboration on some of the topics described in this report and the acquisition and interpretation of new data. Major items on which future work might focus are 1) data collection, 2) geohydrologic mapping, 3) hydraulic characteristics of subsurface geohydrologic units, 4) hydrology of lakes, and 5) hydrologic systems modeling

Minnesota↗
USGS1963

Reconnaissance geology and hydrology on the Nett Lake Indian Reservation, Minnesota

The Nett Lake Indian Reservation is in northern Minnesota, about 210 miles north of Minneapolis and St. Paul. The village of Nett Lake (population about 300) is the only community on the reservation. This report is the result of an investigation made to provide a central water source for the village, at the request of the Public Health Service of the U.S. Department of Health, Education, and Welfare. The climate of the area is continental, characterized by cool, subhumid summers and long, severe winters. The average annual precipitation is 24.2 inches. Altitudes in the area range from about 1,190 feet above mean sea level in the Little Fork River channel on the west border of the reservation to about 1,550 feet on top of the Vermilion end moraine, just south of Nett Lake. During the latter part of the Pleistocene Epoch most of the area was inundated by the waters of glacial Lake Agassiz. The area is now drained by the Little Fork River which flows north into the Rainy River, thence into Lake of the Woods, and eventually into Hudson Bay. The geologic units in the Nett Lake area consist of unconsolidated deposits of Recent and Pleistocene age and crystalline rocks of Precambrian age. Most ground water in the Nett Lake area occurs in three different zones: 1) surficial sand and gravel deposits, 2) lake sand underlying compact lake clay, and 3) bedrock fractures. The lake sand underlying the compact clay is the best source of ground water for the village of Nett Lake. It occurs in a small channel immediately west of the village, and it ranges in depth from about 11 to 30 feet below land surface and in thickness from 0 to about 3 feet. The water level is near the surface. A test well yielded 30 gpm (gallons per minute). Two 15 gpm wells would not exceed the long-term yield of the aquifer and would be adequate for the needs of the village.

Open-File Report↗