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Research about Connecticut

Source-linked reports with geographic coverage including Connecticut.

At least 127 records · Page 7Linked to original sources
USGS1991

Postfledging survival and recruitment of known-origin roseate terns (Sterna dougallii) at Falkner Island, Connecticut

From 1981-1990, 166 (10.1%) of 1636 Roseate Tern (Sterna dougallii) chicks banded from 1978-1985 at Falkner Island, Connecticut, [USA] and 68 (1.0%) of 6904 chicks banded during the same time period at all other colony sites in Connecticut, New York, and Massachusetts, were recaptured as breeding adults at Falkner Island. An analysis of the recapture data of the natal-site recruits resulted in an estimated average survival-and-return rate of 14.7% for the 3-yr period from fledging to first breeding. Assuming a 10% 'permanent' emigration rate of surviving young to other colony sites, the overall prebreeding survival or maturation rate to age 3 of all fledglings raised at Falkner Island from 1978-1985 was estimated to be about 16%. The 1636 chicks banded at Falkner Island comprised only 19.7% of the total of 8540 chicks banded in the three-state area, but the 166 adults that returned to their natal colony site accounted for 71.4% of the 234 known-age survivors from the 1978-1985 cohorts that had nested at Falkner Island through 1990. The recapture as adults of birds first banded as chicks provides an estimate of the maximum degree to which the breeding population at this site was sustained by natal-site recruitment. The capture of a large number of unbanded birds and birds banded as adults elsewhere indicates, however, that about two-thirds of the recent additions to the Roseate Tern breeding population at Falkner Island were immigrants recruited from other colony sites.

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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."

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USGS1991

Water availability and quality from the stratified drift in Anguilla Brook basin, Stonington and North Stonington, Connecticut

The valley of Anguilla Brook is underlain by saturated stratified-drift deposits that, where thick and transmissive, have the potential to yield large quantities of ground water. These deposits are collectively termed the Anguilla Brook aquifer. Long-term yields of four subareas within this aquifer are estimated to range from less than 0.3 to 1.0 million gallons per day. The total yield of all four subareas is estimated to be 2.6 million gallons per day. These yield estimates are based on using the 90-percent duration flow of Anguilla Brook as an index of the water potentially available and on maximum sustainable pumping rates calculated by a mathematical model that used the Theis nonequilibrium equation and image well theory. Development of one or more subareas assumes that most ground water would be derived from induced recharge. This would reduce the flow of Anguilla Brook, and the effect will be most significant during periods when streamflow is low. Limited sampling and analysis indicate that the quality of both surface and ground water in the Anguilla Brook basin is excellent. The concentrations of all constituents analyzed, with the exception of dissolved manganese and iron, were below the drinking-water limits established by the State of Connecticut, or recommended by the U.S. Environmental Protection Agency.

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USGS1990

Water resources data, Connecticut, water year 1989

Water resources data for the 1989 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 12 streamflow-gaging stations, for 24 ungaged stream sites, for 1 tidal-gaging station, for 4 lakes and reservoirs, for 2 harbors, for 5 precipitation stations, and for 179 wells; and (5) water-level records for 35 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.

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USGS1990

Effects of urbanization on peak streamflows in four Connecticut communities, 1980-84

Ratios of peak flows in urban basins to peak flows in rural basins in Connecticut are about 1.5 to 6.1 for the 2-year flood and 1.1 to 4.3 for the 100-year flood. The lower ratios, in each case, apply where 30% of the area is served by storm sewers, and the higher ratios apply where 90% of the area is served by storm sewers. Peak flows for six small urban streams were determined from rainfall and runoff data collected from 1981 to 1984 and from a distributed-routing rainfall-runoff model that simulated storm runoff for the period 1951-80. Recurrence intervals of the peak flows for these streams and three other urban streams were estimated using the log-Pearson Type III method and compared with peak flows for rural streams that were computed from regression equations. A comparison of the ratios of urban to rural peak flows shows that basins where more than 50% of the area is served by storm sewers have urban to rural ratios that are outside the 95% confidence limits of the rural regression equations. Peak flows for such areas can be adjusted graphically for the effects of urbanization if the streams drain less than 10 sq mi and manmade storage is less than 4.5 million cu ft/sq mi. (USGS)

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USGS1989

Bedrock geology of the Bristol quadrangle, Hartford, Litchfield, and New Haven Counties, Connecticut

Metamorphosed strata of sedimentary origin underlie the upland surface of western Connecticut, and nonmetamorphosed sedimentary strata underlie the adjacent lowland surface of central Connecticut. The metamorphic rocks consist chiefly of micaceous schists and gneisses, with minor amounts of pegmatite, amphibolite, and metaquartzite. These rocks represent three formations. They are, in order of decreasing age, the Taine Mountain Formation, Collinsville Formation, and Straits Schist Formation; together they comprise seven members. The formations probably correlate with the Moretown Formation, Hawley Formation, and Goshen Formation of central western Massachusetts, and Vermont. The originally nonmetamorphosed sediments of the formations thus are inferred to range in geologic age from Middle Ordovician to Late Silurian and Early Devonian. Regional metamorphism of the strata may have occurred during the Acadian orogeny at or near the end of Early Devonian time. The nonmetamorphosed strata of the lowland are mainly sandstone; they are correlated with the New Haven Arkose of Middle Triassic age in central Connecticut. Gravimeter traverses across the upland-lowland boundary suggest the presence of a normal fault of a few hundred feet displacement, downthrown on the east. Traces of copper mineralization are found locally in the vicinity of the boundary, and at least one mine produced copper ore during the 1800's. Jointing and foliation planes in the metamorphic rocks may affect slope stability and the ease of excavation. The sedimentary strata are inclined, commonly massive, and poorly exposed.

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USGS1989

Water resources data, Connecticut water year 1987

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."

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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.

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USGS1988

Water resources data, Connecticut water year 1986

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."

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USGS1988

Preliminary appraisal of the effects of land use on water quality in stratified-drift aquifers in Connecticut

The stratified-drift aquifers that underlie 7.9 sq mi of the Potatuck and 12.7 sq mi of the Pomperaug River valley, CT, consist primarily of sand and gravel deposits up to 150 ft thick. Average horizontal hydraulic conductivity of the stratified drift ranges from 20 to 170 ft/day, and groundwater flows through the aquifers at an average rate of 2 to 3 ft/day. Land use in the study areas is changing from primarily undeveloped or agricultural lands to expanding residential, commercial, and light-industrial uses. Water quality data for 1923-82, that include 127 partial chemical analyses of groundwater samples from 38 wells in the two aquifers, were augmented by sampling during 1985 from 21 new stainless-steel wells for selected major inorganic constituents, trace elements, and organic chemicals. Nonparametric statistical procedures were used to compare the water quality data from four land use areas, for the two sampling periods, and between the two aquifers. Human activities associated with agricultural, residential, and industrial/commercial land uses have affected the quality of water in the stratified-drift aquifers underlying these land use areas. Statistical comparisons of water quality data between land use areas show significant differences, with the apparent relations between land use and groundwater being: (1) Median concentrations of most groundwater constituents are smallest in undeveloped areas; (2) Groundwater in agricultural areas has the largest median sulfate and total ammonia plus organic nitrogen concentrations. Agricultural areas are also characterized by groundwater with significantly greater median specific conductance, noncarbonate hardness, carbon dioxide, and magnesium concentrations relative to undeveloped areas; (3) Median concentrations of most major inorganic constituents, excluding potassium, sulfate, and total ammonia plus organic nitrogen, are greater in groundwater in residential areas than in undeveloped and agricultural areas. (4) Groundwater in industrial/commercial areas has the greatest median specific conductance, pH, carbon dioxide, calcium, magnesium, chloride bicarbonate, dissolved solids, boron, and strontium concentrations. (Author 's abstract)

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USGS1987

Water resources data, Connecticut water year 1985

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."

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USGS1987

Ground-penetrating radar study of the thickness and extent of sediments beneath Silver Lake, Berlin and Meriden, Connecticut

A short-pulse ground-penetrating radar system was used to determine the extent and thickness of organic-rich lake-bottom sediments in Silver Lake in south-central Connecticut. Four mi of ground-penetrating radar profiles were obtained along traverses of the frozen lake during March 1984. The radar waves penetrated 6 inches of snow, 1 ft of ice, an average of 4 to 5 ft of water, and 5 ft of soft organic and inorganic deposits. A large area of the lake bottom is underlain by soft sediment exceeding 5 ft in depth. No radar reflections were obtained from the hard subbottom in these areas because the overlying sediment probably contains large proportions of silt and clay that are relatively impervious to radar. Coring along two radar profile lines confirmed the depths of soft sediment calculated from the radar data. Boring logs around the perimeter of the lake indicate that the eastern side may be underlain by till or poorly-sorted sand and gravel, and that the rest of the lake is probably underlain by fine sands and silts with some discontinuous layers of sand and gravel. (USGS)

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