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B.S. Davies

Publications and source records attributed to B.S. Davies.

9 recordsLinked to original sources
USGS1995

Water resources data, Connecticut, water year 1994

Water resources data for the 1994 water year for Connecticut consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels of ground-water wells. Specifically, it contains: (1) discharge records for 44 streamflow-gaging stations; (2) stage-only records for 4 tidal-gaging stations; (3) 41 partial-record or miscellaneous streamflow stations; (4) water-quality records for 14 streamflow-gaging stations, for 15 ungaged stream sites, for 2 lakes and reservoirs, for 22 miscellaneous stations, and for 67 wells; and (5) water-level records for 91 observation wells. Locations of these sites are shown on Figures 1, 2 and 3. Additional water data were collected at various sites involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Connecticut.

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USGS1995

Geohydrology and water quality of the Durham Center Area, Durham, Connecticut

Contaminated ground water is widespread and persistent beneath the Durham Center area in the town of Durham, Conn. Most of the contaminants are organic halides, usually trichloroethene, 1,1,1-trichloroethane, and tetrachloroethene. Less extensive chemical contamination of surface water, soil, and glacial sediments also has been detected. Two manufacturing companies, located at the northern and southern ends of this largely residential area, are believed to be the principal sources of the organic compounds detected in ground water. The contamination of water in the bedrock, the primary source of drinking water throughout the area, is the major environmental concern. Maximum concentrations of trichloroethene in three bed- rock wells range from 4,500 to about 5,500 mg/L (micrograms per liter). Concentrations of trichloroethene greater than 5 mg/L, the maximum contaminant level established for drinking water by the U.S Environmental Protection Agency, have regularly been detected in water samples from many other bedrock wells for at least 9 years. The geohydrology of the area is highly complex. Compact lodgment till that is up to 30 feet thick and probably fractured, overlies the bedrock. The bedrock is lithologically heterogeneous, and con- sists mostly of red fluvial sandstone, siltstone, and conglomerate; it is locally interbedded with black lacustrine shales and gray sandstones. Lithology and stratigraphy interpreted from borehole-geophysical logs at Durham Center are consistent with the Portland Formation subfacies described in earlier geologic studies. Beds strike nearly north-south and dip gently eastward. At least one high-angle normal fault transects the bedrock; it strikes northeast and dips northwest. Acoustic televiewer logs, measurements at out-crops, and azimuthal, square-array, resistivity data indicate a dominance of northeast-striking fractures that dip steeply northwest and southeast. Less prevalent strike directions are north to east-north-east. The till and sedimentary bedrock are dual-porosity, dual-permeability media. The hydraulic conductivity of the bulk mass of till is believed to be on the order of tenths of a foot per day to about 2.5 feet per day, with a total porosity of about 25 percent and an estimated average fracture porosity of less than 1 percent. The reported transmissivities of the bedrock range from less than 1 to about 17,000 feet squared per day and storativity is generally about 10-4, but the accuracy of these values is uncertain. The intergranular porosity of the sandstone units is estimated to average 5 percent, and estimates of fracture porosity from square-array, resistivity soundings at two sites were 1.1 and 2.7 percent. The bedrock has characteristics of both a single aquifer and a multi-unit, artesian or leaky aquifer system. A local ground-water-flow system that includes the upper part of the bedrock is unconfined. A large- scale flow system in deeper parts of the bedrock has transported organic compounds across topographic drainage divides. Borehole-geophysical logs and head measurements indicate that the natural ground- water-flow system in the bedrock has been altered by drilled wells that connect fractures and by with- drawals from wells. A conceptual model of the movement and fate of organic contaminants suggests that (1) nonaqueous phase organic halides are retained near their source; (2) flow is primarily through fractures in the till and through fractures and bedding-plane openings in the sedimentary rocks; (3) retardation of contaminants occurs primarily by diffusion from fractures into the aquifer matrix; and (4) transport directions of dissolved organic halides are controlled by a combination of natural hydraulic gradients, hydraulic gradients produced by the cyclical pumping of wells, and by the strike directions of bedrock faults, fractures, and bedding planes.

Connecticut↗
USGS1994

Water resources data, Connecticut water year 1993

The Water Resources Division of the U.S. Geological Survey, in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Connecticut each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data - Connecticut."

Connecticut↗
USGS1993

Water resources data, Connecticut, water year 1992

Water resources data for the 1992 water year for Connecticut consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels of ground-water wells. Specifically, it contains: (1) discharge records for 44 streamflow-gaging stations, and for 1 tidal volume streamflow station; (2) stage-only records for 3 tidal-gaging stations; (3) 29 partial-record or miscellaneous streamflow stations; (4) water-quality records for 13 streamflow-gaging stations, for 17 ungaged stream sites, for 1 tidal-gaging station, for 2 lakes and reservoirs,; and (5) water-level records for 46 observation wells. Locations of these sites are shown on Figures 1, 2 and 3. Additional water data were collected at various sites involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Connecticut.

Connecticut↗
USGS1991

Water resources data, Connecticut water year 1990

The Water Resources Division of the U.S. Geological Survey, in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Connecticut each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data - Connecticut."

Connecticut↗
USGS1989

Water resources data, Connecticut, water year 1988

Water resources data for the 1988 water year for Connecticut consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground-water wells. Specifically, it contains: (1) discharge records for 47 streamflow-gaging stations, and for 1 tidal volume streamflow station; (2) stage-only records for 4 tidal-gaging stations; (3) content records for 35 lakes and reservoirs; (4) water- quality records for 14 streamflow-gaging stations, for 24 ungaged stream sites, for 1 tidal-gaging station, for 4 lakes and reservoirs, for 2 harbors, for 3 precipitation stations, and for 220 wells; and (5) water-level records for 38 observation wells. Locations of these sites are shown on Figures 1 and 2. Additional water data were collected at various sites involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Connecticut.

Connecticut↗