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David C. Dickerman

Publications and source records attributed to David C. Dickerman.

8 recordsLinked to original sources
USGS2003

Hydrogeology and Simulated Effects of Ground-Water Withdrawals in the Big River Area, Rhode Island

The Rhode Island Water Resources Board is considering expanded use of ground-water resources from the Big River area because increasing water demands in Rhode Island may exceed the capacity of current sources. This report describes the hydrology of the area and numerical simulation models that were used to examine effects of ground-water withdrawals during 1964?98 and to describe potential effects of different withdrawal scenarios in the area. The Big River study area covers 35.7 square miles (mi2) and includes three primary surface-water drainage basins?the Mishnock River Basin above Route 3, the Big River Basin, and the Carr River Basin, which is a tributary to the Big River. The principal aquifer (referred to as the surficial aquifer) in the study area, which is defined as the area of stratified deposits with a saturated thickness estimated to be 10 feet or greater, covers an area of 10.9 mi2. On average, an estimated 75 cubic feet per second (ft3/s) of water flows through the study area and about 70 ft3/s flows out of the area as streamflow in either the Big River (about 63 ft3/s) or the Mishnock River (about 7 ft3/s). Numerical simulation models are used to describe the hydrology of the area under simulated predevelopment conditions, conditions during 1964?98, and conditions that might occur in 14 hypothetical ground-water withdrawal scenarios with total ground-water withdrawal rates in the area that range from 2 to 11 million gallons per day. Streamflow depletion caused by these hypothetical ground-water withdrawals is calculated by comparison with simulated flows for the predevelopment conditions, which are identical to simulated conditions during the 1964?98 period but without withdrawals at public-supply wells and wastewater recharge. Interpretation of numerical simulation results indicates that the three basins in the study area are in fact a single ground-water resource. For example, the Carr River Basin above Capwell Mill Pond is naturally losing water to the Mishnock River Basin. Withdrawals in the Carr River Basin can deplete streamflows in the Mishnock River Basin. Withdrawals in the Mishnock River Basin deplete streamflows in the Big River Basin and can intercept water flowing to the Flat River Reservoir North of Hill Farm Road in Coventry, Rhode Island. Withdrawals in the Big River Basin can deplete streamflows in the western unnamed tributary to the Carr River, but do not deplete streamflows in the Mishnock River Basin or in the Carr River upstream of Capwell Mill Pond. Because withdrawals deplete streamflows in the study area, the total amount of ground water that may be withdrawn for public supply depends on the minimum allowable streamflow criterion that is applied for each basin.

Water-Resources Investigations Report↗
USGS2002

Glacial geology and aquifer characteristics of the Big River area, central Rhode Island

The Rhode Island Water Resources Board (RIWRB), which is responsible for developing the State's major water resources, is concerned that continued growth in demand for water in Rhode Island will severely stress water supplies. In the early 1960s, the State proposed construction of a surface-water reservoir in the Big River Basin in central Rhode Island to meet the growing water demands, but, to date (2001) the U.S. Environmental Protection Agency has not given approval for construction of this reservoir. As an alternative, the RIWRB would like to identify sites in the Big River area stream-aquifer system where high-yield supply wells can be constructed to meet future water demands. A cooperative study was initiated during the summer of 1995 by the U.S. Geological Survey (USGS) and the RIWRB to evaluate ground water as a source of water supply in the Big River area. This report presents the initial results of a multi-year investigation of the three-dimensional characteristics of the surficial aquifer system based on geologic and geophysical field studies, and provides information needed to protect, develop, and manage the Big River area stream-aquifer system. The Big River area includes the entire Big River drainage basin and part of the Mishnock River drainage basin (fig. 1) and covers approximately 35 mi2, including parts of the towns of Coventry, Exeter, and West Greenwich. Most of the Big River area is in Kent County, with a small part in Washington County; it encompasses parts of the Coventry Center, Hope Valley, Crompton, and Slocum 7.5-minute quadrangles. This investigation includes a characterization of the geologic framework and an evaluation of the hydraulic properties of the stream-aquifer system. The Big River area stream-aquifer system is the surficial aquifer and the network of rivers, brooks, lakes, and ponds that overlie and are in hydraulic connection with the aquifer. The surficial materials units of the Big River area and the accompanying bedrock-surface contours (pl. 1) were delineated on the basis of data collected during field mapping, seismic-refraction surveys, ground-penetrating radar surveys, logs from all available wells and test holes, and results of previous investigations. Some streams in the study area lose surface water naturally to the underlying sand and gravel aquifer, whereas others lose water to the aquifer by induced infiltration of streamflow caused by ground-water withdrawals. Most large ground-water withdrawals are from public-supply wells in the sand and gravel aquifer in the Mishnock River Basin. Minimal ground-water withdrawals take place in the Big River Basin, because most of the land is designated as open space and protected from development by State law. The primary use of surface water in the study area is for recreation. Water from the Flat River Reservoir, the largest surface-water body in the study area, is used only for recreational purposes.

Rhode Island↗
USGS2001

Balancing Ground-Water Withdrawals and Streamflow in the Hunt-Annaquatucket-Pettaquamscutt Basin, Rhode Island

Ground water withdrawn for water supply reduces streamflow in the Hunt-Annaquatucket-Pettaquamscutt Basin in Rhode Island. These reductions may adversely affect aquatic habitats. A hydrologic model was prepared by the U.S. Geological Survey in cooperation with the Rhode Island Water Resources Board, Town of North Kingstown, Rhode Island Department of Environmental Management, and Rhode Island Economic Development Corporation to aid water-resource planning in the basin. Results of the model provide information that helps water suppliers and natural-resource managers evaluate strategies for balancing ground-water development and streamflow reductions in the basin.

Fact Sheet↗
USGS2001

Numerical-simulation and conjunctive-management models of the Hunt-Annaquatucket-Pettaquamscutt stream-aquifer system, Rhode Island

Numerical-simulation and optimization techniques were used to evaluate alternatives for the conjunctive management of ground- and surface-water resources of the Hunt­-Annaquatucket­-Pettaquamscutt stream-aquifer system in central Rhode Island. Ground-water withdrawals from the Hunt-Annaquatucket-Pettaquamscutt aquifer exceeded 8 million gallons per day during months of peak water use during 1993­98, and additional withdrawals have been proposed to meet growing demands from within and outside of the system boundary. The system is defined by the Hunt­-Annaquatucket­-Pettaquamscutt aquifer, which is composed of glacial stratified deposits, and the network of rivers, brooks, and ponds that overlie and are in hydraulic connection with the aquifer. Nearly all of the water withdrawn, however, is derived from depletions of flow in the rivers, brooks, and ponds that overlie the aquifer. Streamflow depletions are of concern to environmental agencies because of the adverse effects that reductions in streamflow can have on aquatic and riparian ecosystems. A conjunctive-management model of the stream-aquifer system was developed to simultaneously address the water-demand and streamflow-depletion issues. The objective of the model was to maximize total ground-water withdrawal from the aquifer during July, August, and September. These three months are generally the time of year when water-supply demands are largest and streamflows are simultaneously lowest. Total withdrawal from the aquifer was limited by a set of constraints specified in the model. These constraints were (1) maximum rates of streamflow depletion in the Hunt, Annaquatucket, and Pettaquamscutt Rivers; (2) minimum monthly water demands of each of three water-supply systems that withdraw water from the aquifer; and (3) minimum and maximum withdrawal rates at each supply well. The conjunctive-management model was formulated mathematically as a linear program. The model was solved by a response-matrix technique that incorporates the results of transient, numerical simulation of the stream-aquifer system into the constraint set of the linear program. The basis of the technique was the assumption that streamflow-depletion rates in each river were a linear function of ground-water-withdrawal rates at each well. This assumption was shown to be valid for the conditions evaluated in this study, primarily because of the very high transmissivity of the aquifer near many of the wells pumped for water supply. A transient, numerical model of the system was developed to simulate an average annual cycle of monthly withdrawal and hydrologic conditions representative of the 56-year period 1941­96. The transient model was used to generate characteristic streamflow-depletion responses in each river to simulated withdrawals at each well; these characteristic responses, or response coefficients, were then incorporated directly into the streamflow-depletion constraints of the linear program. Four sets of applications of the conjunctive-management model were made to determine whether total ground-water withdrawal from the aquifer during July, August, and September could be increased over the current total withdrawal for alternative definitions of the maximum rates of streamflow depletion allowed in the Hunt, Annaquatucket, and Pettaquamscutt Rivers. Current conditions were defined as the average monthly withdrawal rates at each supply well, water demands of each of the three water-supply systems, and estimated streamflow-depletion rates during the 6-year period 1993­98. Total withdrawal from all wells in the system from July through September during 1993­98 was 506.5 million gallons. Estimated streamflow-depletion rates for 1993­98 were calculated by use of the transient model, with the 1993­98 average monthly withdrawal rates specified at each supply well. Streamflow-depletion rates calculated for July, August, and September averaged 25 percent of the model-calculated pre-withdrawal streamflow rates for the Hunt River, 19 percent for the Annaquatucket River, and 7 percent for the Pettaquamscutt River. The first set of applications of the model were made with the current estimated rates of streamflow depletion in the Hunt, Annaquatucket, and Pettaquamscutt Rivers. Results of these applications indicated that total withdrawal from the aquifer during July, August, and September could be increased from about 8 to 18 percent (from 546.0 to 596.3 million gallons) over the current total withdrawal. The increased withdrawal would require modifications to the current annual withdrawal schedule of each supply well and, for the 18-percent increase, a modified network of supply wells that would include two new wells in the Annaquatucket River Basin. A second set of model applications then was made to determine if current estimated rates of streamflow depletion in the Hunt River could be reduced without increasing current estimated rates of streamflow depletion in the Annaquatucket or Pettaquamscutt Rivers. Decreases in the current rates of streamflow depletion in the Hunt River would result in increased streamflow in the river during these three months. Results showed that current rates of streamflow depletion in the Hunt River during July, August, and September could be decreased from 5 to 15 percent, depending on whether the existing or modified well network was used. Subsequent model applications indicated that substantial increases in total ground-water withdrawal from the aquifer are possible, but would require increased rates of streamflow depletion in the Annaquatucket and Pettaquamscutt Rivers. Maximum increases in the July through September withdrawal from the aquifer of about 39 to 50 percent (from 705.1 to 760.3 million gallons) over the current total withdrawal were calculated when streamflow-depletion rates in the Annaquatucket and Pettaquamscutt Rivers were allowed to increase from current estimated rates to a maximum of 25 percent of the model-calculated pre-withdrawal streamflow for each river during July, August, and September. Alternatively, it was shown that current estimated rates of streamflow depletion in the Hunt River during July, August, and September could be reduced by as much as 35 percent for the maximum allowed increases in streamflow depletion in the Annaquatucket and Pettaquamscutt Rivers; maximum increased withdrawal from the aquifer, however, would range from 8 to 18 percent over the current total withdrawal for the 35-percent reduction in streamflow-depletion rates in the Hunt River. Results of the different applications of the model demonstrate the usefulness of coupling numerical-simulation and optimization techniques for regional-scale evaluation of water-resource management alternatives. The results of the evaluation must be viewed, however, within the limitations of the quality of data available for the Hunt­-Annaquatucket­-Pettaquamscutt stream-aquifer system and representation of the system by a simulation model. An additional limitation of the analysis was the use of an average annual cycle of monthly withdrawal and hydrologic conditions. Ground-water withdrawal strategies may need to be modified to meet streamflow-depletion constraints during extreme hydrologic events, such as droughts. Contributing areas and sources of water to the supply wells also were delineated by use of a steady-state model of the stream-aquifer system. The model was developed to simulate long-term-average ground-water flow and ground-water/ surface-water interactions in the system during the 56-year period 1941­96. Sources of water to the wells consisted of precipitation and wastewater recharge to the aquifer, streamflow leakage from natural stream-channel losses, streamflow leakage caused by induced infiltration, and lateral ground-water inflow from till and bedrock upland areas.

Rhode Island↗
USGS2000

Water-quality conditions and relation to drainage-basin characteristics in the Scituate Reservoir Basin, Rhode Island, 1982-95

The Scituate Reservoir Basin covers about 94 square miles in north central Rhode Island and supplies more than 60 percent of the State of Rhode Island's drinking water. The basin includes the Scituate Reservoir Basin and six smaller tributary reservoirs with a combined capacity of about 40 billion gallons. Most of the basin is forested and undeveloped. However, because of its proximity to the Providence, Rhode Island, metropolitan area, the basin is subject to increasing development pressure and there is concern that this may lead to the degradation of the water supply. Selected water-quality constituent concentrations, loads, and trends in the Scituate Reservoir Basin, Rhode Island, were investigated locate parts of the basin likely responsible for exporting disproportionately large amounts of water-quality constituents to streams, rivers, and tributary reservoirs, and to determine whether water quality in the basin has been changing with time. Water-quality data collected between 1982 and 1995 by the Providence Water Supply Board PWSB) in 34 subbasins of the Scituate Reservoir Basin were analyzed. Subbasin loads and yields of total coliform bacteria, chloride, nitrate, iron, and manganese, estimated from constituent concentrations and estimated mean daily discharge records for the 1995 water year, were used to determine which subbasins contributed disproportionately large amounts of these constituents. Measurements of pH, color, turbidity, and concentrations of total coliform bacteria, sodium, alkalinity, chloride, nitrate, orthophosphate, iron, and manganese made between 1982 and 1995 by the PWSB were evaluated for trends. To determine the potential effects of human-induced changes in drainage- basin characteristics on water quality in the basin, relations between drainage-basin characteristics and concentrations of selected water-quality constituents also were investigated. Median values for pH, turbidity, total coliform bacteria, sodium, alkalinity, chloride, nitrate, and iron were largest in subbasins with predominately residential land use. Median instantaneous loads reflected drainage-basin size. However, loads normalized by drainage area (median instantaneous yields) also were largest in residential areas where point and non-point sources are likely, and in areas of poorly drained soils. Significant trends in water-quality constituents from 1982 to 1995 in the Scituate Reservoir Basin indicate that the quality of the water resources in the basin may be slowly changing. Scituate Reservoir subbasins with large amounts of residential land use showed increasing trends in alkalinity and chloride. In contrast, subbasins distributed throughout the drainage basin showed increasing trends in pH, color, nitrate, and iron concentrations, indicating that these characteristics and constituents may be affected more by atmospheric deposition. Although changing, water-quality constituent concentrations in the Scituate Reservoir Basin only occasionally exceeded Rhode Island and USEPA water-quality guidelines and standards. Result of correlation analysis between pH, color, turbidity, and concentrations total coliform bacteria, sodium, alkalinity, chloride, nitrate, orthophosphate, iron, and manganese and land use, geology, wetlands, slope, soil drainability, and roads indicated that the percentage of wetlands, roads, and slope appear have the greatest effect on water-quality in the Scituate Reservoir Basin. The percentage of urban, residential, and commercial land use also are important, but to a lesser degree than wetlands, roads, and slope. Finally, geology appears to have the least effect on water quality compared to other drainage-basin characteristics investigated.

Rhode Island↗
USGS1997

Hydrogeology, water quality, and simulation of ground-water-development alternatives in the Usquepaug-Queen ground-water reservoir, southern Rhode Island

The Usquepaug-Queen River Basin study describes the hydrogeology, water quality, and simulation of pumping from wells for selected ground-water-development alternatives in the ground-water reservoir under average (1975-90) and drought (1963-66) conditions. In general, ground-water quality is suitable for most purposes. The study provides an evaluation of the effects of simulated pumping of 4 to 11 million gallons per day of ground water on the stream-wetland-aquifer system. Three principal geologic units underlie the Usquepaug-Queen River Basin glacial stratified deposits (stratified drift), glacial till, and crystalline bedrock. Thick and extensive deposits of saturated coarse-grained stratified deposits form the major and most productive aquifer in the Usquepaug-Queen River Basin. The 36.1-square mile Usquepaug-Queen River Basin is in the Pawcatuck River Basin in southern Rhode Island. Stratified deposits cover about 42 percent of the basin and reach a maximum known thickness of 122 feet. The stratified deposits are subdivided into coarse-grained units (dominantly fine to very coarse sand and gravel) and fine-grained units (dominantly very fine sand, silt, and clay). Transmissivity is highest in coarse-grained stratified materials, which have the capability of yielding relatively high volumes of water to wells. Transmissivity is lowest in fine-grained stratified materials, which consist predominantly of lakebottom deposits. Transmissivity of the stratified drift aquifer ranges from 1,900 to 27,800 feet squared per day, and horizontal hydraulic conductivity ranges from 25 to 470 feet per day. The stratified-drift aquifer is the only aquifer in the Usquepaug-Queen River Basin capable of producing yields of 0.5 million gallons per day or more from individual wells. Pumping from ground-water and surface-water sources in the Usquepaug-Queen River Basin averaged 0.28 million gallons per day during 1989 and 0.48 million gallons per day during 1990. Ground water and surface water (which is primarily ground-water runoff) in the UsquepaugQueen River Basin are suitable for most purposes on the basis of a comparison of physical properties and chemical constituents to drinking-water standards. Ground water in the basin is somewhat corrosive because of its low hydrogen-ion concentration. Specific conductance and concentrations of dissolved chloride and dissolved sodium are high in ground water in parts of the Usquepaug-Queen River Basin, which indicates the effects of highway de-icing salts on groundwater quality. Nitrogen (nitrite plus nitrate) concentrations in some localized areas exceed the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter for drinking water. The effects of selected ground-waterdevelopment alternatives on ground-water levels, wetland-water levels, and streamflow in the Usquepaug-Queen ground-water reservoir were evaluated by means of a three-layer ground-waterflow model. Development alternatives were simulated for average annual (1975-90) and drought (1963-66) conditions. In general, higher simulated pumping rates produced greater drawdowns than lower pumping rates. Drawdowns generally can be reduced by distributing the total pumping over many wells; however, drawdowns were minimal (less than 1.3 feet) in well SNW 906, which was near a major stream (recharge boundary); and drawdowns were substantial (at least 12 feet) in well EXW 33, which was near the edge of the model aquifer boundary (barrier boundary). Total gains in flow from ground-water discharge for all streams in the model area were not affected by the location of wells; however, the amount of ground-water pumpage derived from induced infiltration of streamflow varies significantly. Water levels in the wetlands tend to be constant even during simulated pumping. In general, pumping during simulated drought conditions increased drawdowns fractionally and greatly reduced overall streamflow gains. Pumping from the Usquepaug-Queen stratified-drift aquifer causes infiltration of streamflow along stream segments simulated in the ground-water-flow model. Results of simulations for average conditions show that from 56 to 75 percent of the total water pumped is derived from intercepted ground-water runoff and that the amount of well water derived from induced recharge of streamflow ranged from 20 to 39 percent. The areal extent of contributing areas for selected simulated pumping wells suggest that large areas of stratified drift may need to be protected from land-use practices that are incompatible with the development of potable ground water in the Usquepaug-Queen ground-water reservoir.

Rhode Island↗
USGS1974

Availability of ground water in the Blackstone River area Rhode Island and Massachusetts

The Blackstone River study area covers 83 square miles of northern Rhode Island and 5 square miles of adjacent Massachusetts (fig. 1). It includes parts of the Blackstone, Moshassuck, and Tenmile River basins, and a coastal area that drains to the brackish Seekonk and Providence Rivers. In Rhode Island, all or parts of the suburban towns of Cumberland, Lincoln, North Smithfield, and Smithfield and all or parts of the cities of Central Falls, East Povidence, Pawtucket, Providence, and Woonsocket are within the study area. Also included are parts of the towns Attleboro and North Attleborough in Massachusetts. In 1970, total population was about 240,000, which was equivalent to about one-fourth of the total population of Rhode Island. Fresh water usage in 1970 by public-supply systems and self-supplied industry was about 33 mgd (million gallons per day), which was equal to 22 percent of total fresh water use in Rhode Island for all purposes except generation of electric power (fig. 2). Anticipated increases in population and per capita water requirements are likely to cause the demand for water to more than double within the next 50 years. A significant part of this demand can be met from wells that tap the principal streams. This aquifer yielded an average of 10 mgd in 1970 and is capable of sustaining a much higher yield. The primary objectives of the study were to determine and map the saturated thickness and transmissivity of the stratified-drift aquifer and to assess the potential sustained yield of those parts of the aquifer favorable for large-scale development of water. A secondary objective was to describe ground-water quality and to evaluate the impact of induced infiltration of polluted stream water on the quality of native ground water. This report is based on analysis of drillers' records of more than 700 wells and borings which include 462 lithologic logs; 35 specific-capacity determinations; 12 aquifer tests, including detailed tests at two sites to determine streambed infiltration rates; chemical analyses of 92 ground-water and 15 stream-water samples; and geologic mapping. Selected base data are published in a separate (Johnston and Dickerman, in press). The authors are indebted to well drillers, especially American Drilling and Boring Company, R.E. Chapman Company, and Layne New England Company, for making their records available; to the water departments of the towns of Cumberland and Lincoln, for allowing aquifer tests of their well fields; to the Rhode Island Department of Health, for providing data on water quality and use; and to many other federal, state, and municipal agencies, companies, and individuals who supplied information. Their contributions are gratefully acknowledged.

Massachusetts;Rhode Island↗