Search USGSSearch

SEARCH · Search USGS

Results for “Environmental Conservation”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources

Concentration, flux, and trend estimates with uncertainty for nutrients, chloride, and total suspended solids in tributaries of Lake Champlain, 1990–2014

The U.S. Geological Survey, in cooperation with the New England Interstate Water Pollution Control Commission and the Vermont Department of Environmental Conservation, estimated daily and 9-month concentrations and fluxes of total and dissolved phosphorus, total nitrogen, chloride, and total suspended solids from 1990 (or first available date) through 2014 for 18 tributaries of Lake Champlain. Estimates of concentration and flux, provided separately in Medalie (2016), were made by using the Weighted Regressions on Time, Discharge, and Season (WRTDS) regression model and update previously published WRTDS model results with recent data. Assessment of progress towards meeting phosphorus-reduction goals outlined in the Lake Champlain management plan relies on annual estimates of phosphorus flux. The percent change in annual concentration and flux is provided for two time periods. The R package EGRETci was used to estimate the uncertainty of the trend estimate. Differences in model specification and function between this study and previous studies that used WRTDS to estimate concentration and flux using data from Lake Champlain tributaries are described. Winter data were too sparse and nonrepresentative to use for estimates of concentration and flux but were sufficient for estimating the percentage of total annual flux over the period of record. Median winter-to-annual fractions ranged between 21 percent for total suspended solids and 27 percent for dissolved phosphorus. The winter contribution was largest for all constituents from the Mettawee River and smallest from the Ausable River. For the full record (1991 through 2014 for total and dissolved phosphorus and chloride and 1993 through 2014 for nitrogen and total suspended solids), 6 tributaries had decreasing trends in concentrations of total phosphorus, and 12 had increasing trends; concentrations of dissolved phosphorus decreased in 6 and increased in 8 tributaries; fluxes of total phosphorus decreased in 5 and increased in 10 tributaries; and fluxes of dissolved phosphorus decreased in 4 and increased in 10 tributaries (where the number of increasing and decreasing trends does not add up to 18, the remainder of tributaries had no trends). Concentrations and fluxes of nitrogen decreased in 10 and increased in 4 tributaries and of chloride decreased in 2 and increased in 15 tributaries. Concentrations of total suspended solids decreased in 4 and increased in 8 tributaries, and fluxes of total suspended solids decreased in 3 and increased in 11 tributaries. Although time intervals for the percent changes from this report are not completely synchronous with those from previous studies, the numbers of and specific tributaries with overall negative percent changes in concentration and flux are similar. Concentration estimates of total phosphorus in the Winooski River were used to trace whether changes in trends between a previous study and the current study were due generally to differences in model specifications or differences from 4 years of additional data. The Winooski River analysis illustrates several things: that keeping all model specifications equal, concentration estimates increased from 2010 to 2014; the effects of a smoothing algorithm used in the current study that was not available previously; that narrowing model half-window widths increased year-to-year variations; and that the change from an annual to a 9-month basis by omitting winter estimates changed a few individual points but not the overall shape of the flow-normalized curve. Similar tests for other tributaries showed that the primary effect of differences in model specifications between the previous and current studies was perhaps to increase scatter over time but that changes in trends generally were the result of 4 years of additional data rather than artifacts of model differences.

New York, Vermont

Groundwater quality in the Delaware, Genesee, and St. Lawrence River Basins, New York, 2015

The U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, collected groundwater samples from 5 production wells and 5 domestic wells in the Delaware River Basin, 8 production wells and 7 domestic wells in the Genesee River Basin, and 1 municipal well, 7 production wells, and 13 domestic wells in the St. Lawrence River Basin in New York. All samples were collected from May through November 2015 in an effort to characterize groundwater quality in these basins. The samples were collected and processed by using standard U.S. Geological Survey procedures and were analyzed for 148 physiochemical properties and constituents, including dissolved gases, major ions, nutrients, trace elements, pesticides, volatile organic compounds, radionuclides, and indicator bacteria. The Delaware River Basin study area covers 2,360 square miles (mi 2 ) in southeastern New York. Of the 10 wells sampled in the Delaware River Basin, 3 are completed in sand and gravel, and 7 are completed in bedrock. Groundwater in the Delaware River Basin was generally of good quality, although properties and concentrations of some constituents—pH, iron, manganese, aluminum, radon-222, and total coliform bacteria—sometimes equaled or exceeded primary, secondary, or proposed drinking-water standards. The constituent most frequently detected in concentrations exceeding drinking-water standards (10 of 10 samples) was radon-222. The Genesee River Basin study area includes the entire 2,439 mi 2 of the basin in western New York. Of the 15 wells sampled in the Genesee River Basin, 6 are completed in sand and gravel, and 9 are completed in bedrock. Groundwater in the Genesee River Basin was generally of good quality, although properties and concentrations of some constituents—chloride, sodium, dissolved solids, iron, manganese, aluminum, arsenic, radon-222, methane, total coliform bacteria, fecal coliform bacteria, and Escherichia coli bacteria—sometimes equaled or exceeded primary, secondary, or proposed drinking-water standards. The constituent most frequently detected in concentrations exceeding drinking-water standards (12 of 15 samples) was radon-222. The St. Lawrence River Basin study area includes the entire 5,650 mi 2 of the basin in northeastern New York. Of the 21 wells sampled in the St. Lawrence River Basin, 7 are completed in sand and gravel, and 14 are completed in bedrock. Groundwater in the St. Lawrence River Basin was generally of good quality, although properties and concentrations of some constituents—pH, chloride, sodium, dissolved solids, iron, manganese, sulfate, nitrate, radon-222, total coliform bacteria, fecal coliform bacteria, and Escherichia coli bacteria—sometimes equaled or exceeded primary, secondary, or proposed drinking-water standards. The constituent most frequently detected in concentrations exceeding drinking-water standards (14 of 21 samples) was radon-222.

New York

Use of time domain electromagnetic soundings and borehole electromagnetic induction logs to delineate the freshwater/saltwater interface on southwestern Long Island, New York, 2015–17

The U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, used surface and borehole geophysical methods to delineate the freshwater/saltwater interface in coastal plain aquifers along the southwestern part of Long Island, New York. Over pumping of groundwater in the early 20th century combined with freshwater/saltwater interfaces at the coastline created saltwater intrusion in the upper glacial, Jameco, Magothy, and Lloyd aquifers. This study documents, for the first time, extensive saltwater intrusion of the Lloyd aquifer along the southwestern coast of Long Island, N.Y. Several public-supply wells in the southern parts of Nassau, Queens, and Kings Counties have been adversely affected by saltwater intrusion causing supply wells to be shutdown and abandoned. Due to the ongoing groundwater pumping in southern Nassau County, the freshwater/saltwater interface requires delineation and monitoring for any inland movement. In 2015–17, the U.S. Geological Survey collected time domain electromagnetic soundings at 12 locations and borehole electromagnetic induction conductivity logs at 9 wells within the study area to delineate several saltwater intrusion wedges. The upper glacial, Jameco, and Magothy aquifers were grouped into one aquifer complex within the study area to simplify interpretations. The coastal plain sediments increase in thickness from west to east and north to south because of their regional dip toward the southeast. Three separate wedges, shallow, intermediate, and deep, of saltwater intrusion were delineated in the upper glacial, Jameco, and Magothy aquifer complex. In addition, analysis of geophysical logs collected in an open borehole of a test well in southern Queens County in 1989 revealed the Lloyd aquifer was nearly completely intruded by saltwater with an estimated chloride concentration of 15,000 milligrams per liter. The geophysical logs from this well provides, for the first time, definitive proof of saltwater intrusion of the Lloyd aquifer on Long Island’s south shore, suggesting the freshwater/saltwater interface was at the coastline and not miles offshore as theorized by previous studies.

New York

Aquifer transmissivity in Nassau, Queens, and Kings Counties, New York, estimated from specific-capacity tests at production wells

As part of a cooperative effort between the U.S. Geological Survey and the New York State Department of Environmental Conservation to evaluate the sustainability of Long Island’s sole-source aquifer system, the transmissivities of four aquifers were estimated from specific-capacity tests at 447 production wells in Nassau, Queens, and Kings Counties on Long Island, New York. The specific-capacity test data, which included pumping rate, pumping duration, and drawdown, were obtained from published and unpublished records of driller-reported acceptance tests collected at production wells screened in the upper glacial, Jameco, Magothy, or Lloyd aquifers. Pumping rates from the production wells during the tests generally were greater than 400 gallons per minute and ranged up to 1,800 gallons per minute. Pumping duration generally was 8 hours or more. Transmissivities were estimated from the specific-capacity data by the Cooper-Jacob approximation of the Theis equation. The transmissivity estimates are considered rough approximations because the aquifers do not meet the ideal assumptions of the method, well losses and partial penetration were not accounted for, and aquifer storage coefficients were not known but were only estimated from available data. The transmissivities estimated from production wells screened in the upper glacial aquifer in the outwash plain south of the moraine generally were greater than those of the aquifer north of the moraine. The transmissivities estimated from the wells screened in the upper glacial aquifer south of the moraine typically ranged (as defined by the 10th and 90th percentiles) from 3,800 to 15,000 feet squared per day (ft 2 /d), with a median value of 7,300 ft 2 /d. The transmissivities estimated from the wells screened in the upper glacial aquifer north of the moraine typically ranged from 2,100 to 7,400 ft 2 /d, with a median value of 4,400 ft 2 /d. The Jameco aquifer generally had the highest estimated transmissivities of all the aquifers analyzed. The estimated transmissivities for the Jameco aquifer typically ranged from 5,500 to 43,000 ft 2 /d, with a median value of 16,000 ft 2 /d. The Magothy and Lloyd aquifers had similar estimated transmissivities. The transmissivities estimated for the Magothy aquifer typically ranged from 2,700 to 13,000 ft 2 /d, with a median of 7,100 ft 2 /d. The estimated transmissivities of the Lloyd typically ranged from 3,000 to 14,000 ft 2 /d, with a median of 7,200 ft 2 /d.

New York

Organic Compounds and Trace Elements in Fish Tissue and Bed Sediment in the Delaware River Basin, New Jersey, Pennsylvania, New York, and Delaware, 1998-2000

As part of the National Water-Quality Assessment (NAWQA) program activities in the Delaware River Basin (DELR), samples of fish tissue from 21 sites and samples of bed sediment from 35 sites were analyzed for a suite of organic compounds and trace elements. The sampling sites, within subbasins ranging in size from 11 to 600 square miles, were selected to represent 5 main land-use categories in the DELR -forest, low-agricultural, agricultural, urban, and mixed use. Samples of both fish tissue and bed sediment were also collected from 4 'large-river' sites that represented drainage areas ranging from 1,300 to 6,800 square miles, areas in which the land is used for a variety of purposes. One or more of the organochlorine compounds-DDT and chlordane metabolites, polychlorinated biphenyls (total PCBs), and dieldrin- were detected frequently in samples collected over a wide geographic area. One or more of these compounds were detected in fish-tissue samples from 92 percent of the sites and in bed-sediment samples from 82 percent of the sites. Concentrations of total DDT, total chlordanes, total PCBs, and dieldrin in whole white suckers and in bed sediment were significantly related to urban/industrial basin characteristics, such as percentage of urban land use and population density. Semi-volatile organic compounds (SVOCs)-total polycyclic aromatic hydrocarbons (PAHs), total phthalates, and phenols- were detected frequently in bed-sediment samples. All three types of SVOCs were detected in samples from at least one site in each land-use category. The highest detection rates and concentrations typically were in samples from sites in the urban and mixed land-use categories, as well as from the large-river sites. Concentrations of total PAHs and total phthalates in bed-sediment samples were found to be statistically related to percentages of urban land use and to population density in the drainage areas represented by the sampling sites. The samples of fish tissue and bed sediment collected throughout the DELR were analyzed for a large suite of trace elements, but results of the analyses for eight elements-arsenic, cadmium, chromium, copper, lead, nickel, mercury, and zinc- that are considered contaminants of concern are described in this report. One or more of the eight trace elements were detected in samples from every fish tissue and bed-sediment sampling site, and all of the trace elements were detected in samples from 97 percent of the bed-sediment sites. The concentrations of organic compounds and trace elements in the DELR samples were compared to applicable guidelines for the protection of wildlife and other biological organisms. Concentrations of total DDT, total chlordanes, total PCBs, and dieldrin in fish-tissue samples from 14 sites exceeded one or more of the Wildlife Protective Guidelines established by the New York State Department of Environmental Conservation. Concentrations of one or more organic compounds in samples from 16 bed-sediment sites exceeded the Threshold Effects Concentrations (TEC) of the Canadian Sediment Quality Guidelines, and concentrations of one or more of the eight trace elements in samples from 38 bed-sediment sites exceeded the TEC. (The TEC is the concentration below which adverse biological effects in freshwater ecosystems are expected to be rare.) Concentrations of organic compounds in samples from some bed-sediment sites exceeded the Canadian Probable Effects Concentrations (PEC), and concentrations of trace elements in samples from 18 sites exceeded the PEC. (The PEC is the concentration above which adverse effects to biological organisms are expected to occur frequently). Concentrations of organic compounds and trace elements in samples from the DELR were compared to similar data from other NAWQA study units in the northeastern United States and also data from the Mobile River (Alabama) Basin and the Northern Rockies Intermontane Basin study units. Median concentrations of to

Scientific Investigations Report

Characterization of Preferential Ground-Water Seepage From a Chlorinated Hydrocarbon-Contaminated Aquifer to West Branch Canal Creek, Aberdeen Proving Ground, Maryland, 2002-04

Wetlands act as natural transition zones between ground water and surface water, characterized by the complex interdependency of hydrology, chemical and physical properties, and biotic effects. Although field and laboratory demonstrations have shown efficient natural attenuation processes in the non-seep wetland areas and stream bottom sediments of West Branch Canal Creek, chlorinated volatile organic compounds are present in a freshwater tidal creek at Aberdeen Proving Ground, Maryland. Volatile organic compound concentrations in surface water indicate that in some areas of the wetland, preferential flow paths or seeps allow transport of organic compounds from the contaminated sand aquifer to the overlying surface water without undergoing natural attenuation. From 2002 through 2004, the U.S. Geological Survey, in cooperation with the Environmental Conservation and Restoration Division of the U.S. Army Garrison, Aberdeen Proving Ground, characterized preferential ground-water seepage as part of an ongoing investigation of contaminant distribution and natural attenuation processes in wetlands at this site. Seep areas were discrete and spatially consistent during thermal infrared surveys in 2002, 2003, and 2004 throughout West Branch Canal Creek wetlands. In these seep areas, temperature measurements in shallow pore water and sediment more closely resembled those in ground water than those in nearby surface water. Generally, pore water in seep areas contaminated with chlorinated volatile organic compounds had lower methane and greater volatile organic compound concentrations than pore water in non-seep wetland sediments. The volatile organic compounds detected in shallow pore water in seeps were spatially similar to the dominant volatile organic compounds in the underlying Canal Creek aquifer, with both parent and anaerobic daughter compounds detected. Seep locations characterized as focused seeps contained the highest concentrations of chlorinated parent compounds, relatively low concentrations of chlorinated daughter compounds, and insignificant concentrations of methane in shallow pore water samples. These seeps were primarily along the creek edge or formed a dendritic-like pattern between the wetland and creek channel. In contrast, seep locations characterized as diffuse seeps contained relatively high concentrations of chlorinated daughter compounds (or a mixture of daughter and parent compounds) and detectable methane concentrations in shallow pore water samples. These seeps were primarily along the wetland boundary. Qualitative thermal infrared surveys coupled with quantitative verification of temperature differences, and screening for volatile organic compound and methane concentrations proved to be effective tools in determining the overall extent of preferential seepage. Hydrologic and physical properties of wetland sediments were characterized at two focused and one diffuse seep location. In the seeps with focused discharge, measured seepage was consistent over the tidal cycle, whereas more variability with tidal fluctuation was measured in the diffuse seep location. At all locations, areas were identified within the general seep boundaries where discharge was minimal. In all cases, the geometric mean of non-zero vertical flux measurements was greater than those previously reported in the non-seep wetland sediments using flow-net analysis. Flux was greater in the focused discharge areas than in the diffuse discharge area, and all fluxes were within the range reported in the literature for wetland discharge. Vertical hydraulic conductivity estimated from seepage flux and a mean vertical gradient at seeps with focused discharge resulted in a minimum hydraulic conductivity two orders of magnitude greater than those estimated in the non-seep sediment. In contrast, vertical conductivity estimates at a diffuse seep were similar to estimates along a nearby line of section through a non-seep area.

Scientific Investigations Report

Geohydrology of the Unconsolidated Valley-Fill Aquifer in the Meads Creek Valley, Schuyler and Steuben Counties, New York

The Meads Creek valley encompasses 70 square miles of predominantly forested uplands in the upper Susquehanna River drainage basin. The valley, which was listed as a Priority Waterbody by the New York State Department of Environmental Conservation in 2004, is prone to periodic flooding, mostly in its downstream end, where development is occurring most rapidly. Hydraulic characteristics of the unconsolidated valley-fill aquifer were evaluated, and seepage rates in losing and gaining tributaries were calculated or estimated, in an effort to delineate the aquifer geometry and identify the factors that contribute to flooding. Results indicated that (1) Meads Creek gained about 61 cubic feet of flow per second (about 6.0 cubic feet per second per mile of stream channel) from ground-water discharge and inflow from tributaries in its 10.2-mile reach between the northernmost and southernmost measurement sites; (2) major tributaries in the northern part of the valley are not significant sources of recharge to the aquifer; and (3) major tributaries in the central and southern part of the valley provide recharge to the aquifer. The ground-water portion of streamflow in Meads Creek (excluding tributary inflow) was 11.3 cubic feet per second (ft3/s) in the central part of the valley and 17.2 ft3/s in the southern part - a total of 28.5 ft3/s. Ground-water levels were measured in 29 wells finished in unconfined deposits for construction of a potentiometric-surface map to depict directions of ground-water flow within the valley. In general, ground water flows from the edges of the valley toward Meads Creek and ultimately discharges to it. The horizontal hydraulic gradient for the entire 12-mile-long aquifer averages about 30 feet per mile, whereas the gradient in the southern fourth of the valley averages about half that - about 17 feet per mile. A water budget for the aquifer indicated that 28 percent of recharge was derived from precipitation that falls on the aquifer, 32 percent was from losing reaches of tributaries, 38 percent was unchanneled flow from hillsides that slope toward the valley (this estimate includes runoff and shallow ground-water inflow from till and bedrock), and the remaining 2 percent was from deep ground-water inflow from till and bedrock to the sides and bottom of the aquifer. Nearly all (94 percent) of the water discharged from the aquifer is equivalent to the streamflow gain in Meads Creek; the remaining 6 percent discharges as deep outflow to unconsolidated deposits in the Cohocton River valley. Several characteristics of the Meads Creek valley may contribute to flooding in the downstream area: (1) the southward decrease in the ground-water gradient impedes the ability of the aquifer to transmit water southward and can cause water levels to rise, (2) a high water table, typically only 5 to 10 feet below land surface, results in little storage capacity to absorb water from large storms, (3) a downstream narrowing of the valley impedes the southward flow of ground water and can cause water levels to rapidly rise during periods of prolonged or heavy precipitation, and (4) the upland slopes (till-covered bedrock) produce rapid runoff that recharges the aquifer. The combined effect of these conditions limits the ability of the aquifer to transmit sudden, large increases in recharge from precipitation and thereby provides a high potential for flooding in the southern third of the valley.

Scientific Investigations Report

Effects of recreational flow releases on natural resources of the Indian and Hudson Rivers in the Central Adirondack Mountains, New York, 2004-06

The U.S. Geological Survey (USGS), the New York State Department of Environmental Conservation (NYSDEC), and Cornell University carried out a cooperative 2-year study from the fall of 2004 through the fall of 2006 to characterize the potential effects of recreational-flow releases from Lake Abanakee on natural resources in the Indian and Hudson Rivers. Researchers gathered baseline information on hydrology, temperature, habitat, nearshore wetlands, and macroinvertebrate and fish communities and assessed the behavior and thermoregulation of stocked brown trout in study reaches from both rivers and from a control river. The effects of recreational-flow releases (releases) were assessed by comparing data from affected reaches with data from the same reaches during nonrelease days, control reaches in a nearby run-of-the-river system (the Cedar River), and one reach in the Hudson River upstream from the confluence with the Indian River. A streamgage downstream from Lake Abanakee transmitted data by satellite from November 2004 to November 2006; these data were used as the basis for developing a rating curve that was used to estimate discharges for the study period. River habitat at most study reaches was delineated by using Global Positioning System and ArcMap software on a handheld computer, and wetlands were mapped by ground-based measurements of length, width, and areal density. River temperature in the Indian and Hudson Rivers was monitored continuously at eight sites during June through September of 2005 and 2006; temperature was mapped in 2005 by remote imaging made possible through collaboration with the Rochester Institute of Technology. Fish communities at all study reaches were surveyed and characterized through quantitative, nearshore electrofishing surveys. Macroinvertebrate communities in all study reaches were sampled using the traveling-kick method and characterized using standard indices. Radio telemetry was used to track the movement and persistence of stocked brown trout (implanted with temperature-sensitive transmitters) in the Indian and Hudson Rivers during the summer of 2005 and in all three rivers during the summer of 2006. The releases had little effect on river temperatures, but increased discharges by about one order of magnitude. Regardless of the releases, river temperatures at all study sites commonly exceeded the threshold known to be stressful to brown trout. At most sites, mean and median water temperatures on release days were not significantly different, or slightly lower, than water temperatures on nonrelease days. Most differences were very small and, thus, were probably not biologically meaningful. The releases generally increased the total surface area of fast-water habitat (rapids, runs, and riffles) and decreased the total surface area of slow-water habitat (pools, glides, backwater areas, and side channels). The total surface areas of wetlands bordering the Indian River were substantially smaller than the surface areas bordering the Cedar River; however, no channel geomorphology or watershed soil and topographic data were assessed to determine whether the releases or other factors were mainly responsible for observed differences. Results from surveys of resident biota indicate that the releases generally had a limited effect on fish and macroinvertebrate communities in the Indian River and had no effect on communities in the Hudson River. Compared to fish data from Cedar River control sites, the impoundment appeared to reduce total density, biomass, and richness in the Indian River at the first site downstream from Lake Abanakee, moderately reduce the indexes at the other two sites on the Indian River, and slightly reduce the indexes at the first Hudson River site downstream from the confluence with the Indian River. The densities of individual fish populations at all Indian River sites were also reduced, but related effects on fish populations in the Hudson River were less evident. Altho

Scientific Investigations Report

Hydrogeology of the stratified-drift aquifers in the Cayuta Creek and Catatonk Creek valleys in parts of Tompkins, Schuyler, Chemung, and Tioga Counties, New York

The surficial deposits, areal extent of aquifers, and the water-table configurations of the stratified-drift aquifer systems in the Cayuta Creek and Catatonk Creek valleys and their large tributary valleys in Tompkins, Schuyler, Chemung, and Tioga Counties, New York were mapped in 2009, in cooperation with the New York State Department of Environmental Conservation. Well and test-boring records, surficial deposit maps, Light Detection and Ranging (LIDAR) data, soils maps, and horizontal-to-vertical ambient-noise seismic surveys were used to map the extent of the aquifers, construct geologic sections, and determine the depth to bedrock (thickness of valley-fill deposits) at selected locations. Geologic materials in the study area include sedimentary bedrock, unstratified drift (till), stratified drift (glaciolacustrine and glaciofluvial deposits), and recent alluvium. Stratified drift consisting of glaciofluvial sand and gravel is the major component of the valley fill in this study area. The deposits are present in sufficient amounts in most places to form extensive unconfined aquifers throughout the study area and, in some places, confined aquifers. Stratified drift consisting of glaciolacustrine fine sand, silt, and clay are present locally in valleys underlying the surficial sand and gravel deposits in the southern part of the Catatonk Creek valley. These unconfined and confined aquifers are the source of water for most residents, farms, and businesses in the valleys. A generalized depiction of the water table in the unconfined aquifer was constructed using water-level measurements made from the 1950s through 2010, as well as LIDAR data that were used to determine the altitudes of perennial streams at 10-foot contour intervals and water surfaces of ponds and wetlands that are hydraulically connected to the unconfined aquifer. The configuration of the water-table contours indicate that the general direction of groundwater flow within Cayuta Creek and Catatonk Creek stratified-drift aquifers is predominantly from the valley walls toward the main streams in the valleys. The groundwater discharges from the aquifer system to the main-stem streams in the valleys. Locally, the direction of groundwater flow is radially away from groundwater mounds that have formed beneath upland tributaries that typically lose water where they flow on alluvial fans in the valleys. In some places, groundwater that would normally flow toward streams is intercepted by pumping wells.

New York

Hydrogeology of the West Branch Delaware River basin, Delaware County, New York

In 2009, the U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, began a study of the hydrogeology of the West Branch Delaware River (Cannonsville Reservoir) watershed. There has been recent interest by energy companies in developing the natural gas reserves that are trapped within the Marcellus Shale, which is part of the Hamilton Group of Devonian age that underlies all the West Branch Delaware River Basin. Knowing the extent and thickness of stratified-drift (sand and gravel) aquifers within this basin can help State and Federal regulatory agencies evaluate any effects on these aquifers that gas-well drilling might produce. This report describes the hydrogeology of the 455-square-mile basin in the southwestern Catskill Mountain region of southeastern New York and includes a detailed surficial geologic map of the basin. Analysis of surficial geologic data indicates that the most widespread surficial geologic unit within the basin is till, which is present as deposits of ablation till in major stream valleys and as thick deposits of lodgment till that fill upland basins. Till and colluvium (remobilized till) cover about 89 percent of the West Branch Delaware River Basin, whereas stratified drift (outwash and ice-contact deposits) and alluvium account for 8.9 percent. The Cannonsville Reservoir occupies about 1.9 percent of the basin area. Large areas of outwash and ice-contact deposits occupy the West Branch Delaware River valley along its entire length. These deposits form a stratified-drift aquifer that ranges in thickness from 40 to 50 feet (ft) in the upper West Branch Delaware River valley, from 70 to 140 ft in the middle West Branch Delaware River valley, and from 60 to 70 ft in the lower West Branch Delaware River valley. The gas-bearing Marcellus Shale underlies the entire West Branch Delaware River Basin and ranges in thickness from 600 to 650 ft along the northern divide of the basin to 750 ft thick along the southern divide. The depth to the top of the Marcellus Shale ranges from 3,240 ft along the northern basin divide to 4,150 ft along the southern basin divide. Yields of wells completed in the aquifer are as high as 500 gallons per minute (gal/min). Springs from fractured sandstone bedrock are an important source of domestic and small municipal water supplies in the West Branch Delaware River Basin and elsewhere in Delaware County. The average yield of 178 springs in Delaware County is 8.5 gal/min with a median yield of 3 gal/min. An analysis of two low-flow statistics indicates that groundwater contributions from fractured bedrock compose a significant part of the base flow of the West Branch Delaware River and its tributaries.

New York

Flood-inundation maps for the Schoharie Creek at Prattsville, New York, 2014

Digital flood-inundation maps for a 2.6-mile reach of the Schoharie Creek at Prattsville, New York, were created by the U.S. Geological Survey (USGS) in cooperation with the New York State Department of Environmental Conservation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ , depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Schoharie Creek at Prattsville (station number 01350000). Near-real-time stages at this streamgage may be obtained online from the USGS National Water Information System ( http://waterdata.usgs.gov/ ) or the National Weather Service Advanced Hydrologic Prediction Service ( http://water.weather.gov/ahps/ ), which also forecasts flood hydrographs at this site. National Weather Service-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas and depths of flood inundation. Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the stage-discharge relation (rating 82.0) at the Schoharie Creek at Prattsville streamgage (station 01350000) and high-water marks from the flood of August 28, 2011. The hydraulic model was then used to compute 17 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to greater than the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model, derived from light detection and ranging (lidar) data having a 0.61-foot vertical root-mean squared error and 6.6-foot horizontal resolution, in order to delineate the area flooded at each water level. These flood-inundation maps, along with near-real-time stage data from USGS streamgages and forecasted stage data from the National Weather Service, can provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for postflood recovery efforts.

New York

Historical water-quality data from the Harlem River, New York

Data specific to the Harlem River, New York, have been summarized and are presented in this report. The data illustrate improvements in the quality of water for the past 65 years and emphasize the importance of a continuous water-quality record for establishing trends in environmental conditions. Although there is a paucity of sediment-quality data, the New York City Department of Environmental Protection (NYCDEP) Bureau of Wastewater Treatment has maintained a water-quality monitoring network in the Harlem River (and throughout the harbor of New York City) to which 61 combined sewer outfalls discharge effluent. In cooperation with the NYCDEP, the U.S. Geological Survey evaluated water-quality data collected by the NYCDEP dating back to 1945, which indicate trends in water quality and reveal improvement following the 1972 passage of the Clean Water Act. These improvements are indicated by the steady increase in median dissolved oxygen concentrations and an overall decrease in fecal indicator bacteria concentrations starting in the late 1970s. Further, the magnitude of the highest fecal indicator bacteria concentrations (that is, the 90th percentile) in samples collected from the Harlem River have decreased significantly over the past four decades. Other parameters of water quality used to gauge the health of a water body include total suspended solids and nutrient (inorganic forms of nitrogen and phosphorus) concentrations—mean concentrations for these indicators have also decreased in the past decades. The limited sediment data available for one sample in the Harlem River indicate concentrations of copper, zinc, and lead are above sediment-quality thresholds set by the New York State Department of Environmental Conservation. However, more data are needed to better understand the changes in both sediment and water quality in the Harlem River, both as the tide cycles and during precipitation events. As a partner in the Urban Waters Federal Partnership, the U.S. Geological Survey has worked to address the chronic water-quality concerns of the Harlem River by compiling relevant data and studies, which is an important component for understanding and rectifying water-quality problems within a watershed.

New York

Geohydrology and water quality of the unconsolidated aquifers in the Enfield Creek Valley, town of Enfield, Tompkins County, New York

From 2013 to 2018, the U.S. Geological Survey, in cooperation with the Town of Enfield and the Tompkins County Planning Department, studied the unconsolidated aquifer in the Enfield Creek Valley in the town of Enfield, Tompkins County, New York. The valley will likely undergo future development as the population of Tompkins County increases and spreads out from the metropolitan areas. The Town of Enfield, Tompkins County, and the New York State Departments of Health and Environmental Conservation need geohydrologic information to help planners develop a more comprehensive approach to water-resource management in Tompkins County. The Enfield Creek Valley is underlain by an unconfined aquifer that consists of saturated alluvium, alluvial-fan deposits, and ice-contact (kame) sand and gravel. A confined aquifer of discontinuous ice-contact sand and gravel overlies bedrock. Depth to bedrock in the valley ranges from about 50 feet below land surface from just north of the Enfield Creek divide in the northern part of the aquifer to the confluence of Fivemile Creek to at least 140 feet below land surface from Fivemile Creek to where the valley orientation changes from north-south to northwest-southeast. Depth to bedrock is much shallower from the valley orientation change to the southeastern part of the aquifer because Enfield Creek has carved through overlying sediments into bedrock as the creek drops 450 feet into the Cayuga Inlet Valley. A small buried valley running south to north was identified within the Fivemile Creek drainage along the western edge of the town. However, the valley fill consists of glacial till, and no sand-and-gravel aquifer is present. The unconfined aquifers are recharged by direct infiltration of precipitation, surface runoff, and shallow subsurface flow from hillsides, and by seepage loss from streams overlying the aquifer. The confined aquifers are recharged mostly by precipitation that enters the adjacent valley walls, by groundwater flowing from bordering till or bedrock, and by flow from the bottom of the valley. Also, some recharge may be occurring where confining units are absent or from confining units with sediments of moderate permeability. Groundwater discharges to Enfield Creek, its tributaries, and wetlands and is lost through evapotranspiration from the water table or is withdrawn from domestic, commercial, and agricultural wells. About 700 individual well owners depend on the unconsolidated aquifers for their water supply. An estimated 28,300,000 gallons per year are withdrawn. Groundwater samples were collected from eight test wells drilled for this study, and six surface-water samples were collected from five locations on Enfield Creek. Of the eight wells sampled, two were finished in unconfined sand-and-gravel aquifers, two were finished in confined sand-and-gravel aquifers, and four were finished at or near the shale bedrock surface. Water quality in the study area generally met State and Federal drinking-water standards. However, some samples exceeded maximum contaminant levels for barium (25 percent of samples) and secondary maximum containment levels for chloride (25 percent), dissolved solids (25 percent of samples), iron (70 percent of samples), and manganese (75 percent of samples). Groundwater from 75 percent of the wells sampled for methane had concentrations greater than the Office of Surface Mining Reclamation and Enforcement recommended action level of 10 to 28 milligrams per liter. The two deepest wells sampled, TM1075 and TM1077, had the highest specific conductance, chloride, and sodium concentrations of all wells sampled. The chloride/bromide ratios of these samples suggest the source may represent a mixture of saline formation waters with shallow dilute groundwater and may receive recharge contribution from two tributaries overlying bedrock to the west and southwest of the aquifer. In general, the highest yields are from wells completed within about 50 feet below land surface, which may tap either type of aquifer.

New York

Time-domain electromagnetic soundings and passive-seismic measurements for delineation of saline groundwater in the Genesee Valley-fill aquifer system, western New York, 2016–17

The U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, used noninvasive surface geophysics in the investigation of the distribution of saline groundwater in the valley-fill aquifer system of the Genesee River Valley near the former Retsof salt mine in western New York. In 1994, the Retsof salt mine, the largest of its kind in the western hemisphere, underwent a catastrophic roof collapse that resulted in groundwater inflow from the valley-fill aquifer system and bedrock fracture zones into the mine through two bedrock-rubble chimneys and the subsequent dissolution and filling of the mine with saturated brine. Since the early 2000s, except for a period of remedial pumping in 2006 to 2013, high-salinity water has migrated upward through the rubble chimneys into the basal part the aquifer system. The extent of saline-water migration within the aquifer system had not been evaluated since the end of remedial pumping when all the monitoring wells were grouted shut and abandoned. Installation of a monitoring-well network would be expensive and difficult given the thickness and heterogeneous character of valley fill. An investigation of the current extent of saline water in the aquifer system was warranted because the basal part of the aquifer is shallow to the north and it is used for water supply. In fall 2016 and fall 2017, the U.S. Geological Survey collected time-domain electromagnetic soundings at 105 sites along 13 cross-valley transects north and south of the mine-collapse area, east of Piffard, and on the Fowlerville Moraine. The time-domain electromagnetic soundings were colocated with passive-seismic measurements to estimate the bedrock-surface elevation through use of a regression equation developed from measurements at well sites with reported bedrock depths in the study area. An integrated analysis of the time-domain electromagnetic soundings with the depth-to-bedrock estimates, well logs, and past chloride-monitoring data suggests the presence of a zone of high electrical conductivity associated with saline water in the confined lower part of the valley-fill aquifer system. This high-salinity zone delineated in the lower confined aquifer extends from the mine-collapse area northward for more than 2.5 miles (4.0 kilometers). The chloride concentration in groundwater within this high-conductivity zone may be about 20,000 milligrams per liter. Saline water flowing upward through the bedrock-rubble chimneys and mixing with northward groundwater flow in the lower confined aquifer likely is a major source of chlorides for this high-conductivity zone. The northern extent of the zone is unclear because of the presence of highly saline water zones that were delineated by time-domain electromagnetic soundings in the lower confined aquifer and uppermost bedrock and are probably associated with historic salt-solution wells in Piffard or possibly sourced from natural brine pools.

New York

Hydrogeology of the Susquehanna River valley-fill aquifer system in the towns of Conklin and Kirkwood, Broome County, New York

The hydrogeology of the Susquehanna River valley-fill aquifer system and adjacent areas in south-central Broome County, New York, was investigated in cooperation with the New York State Department of Environmental Conservation. The study area encompasses roughly 55.5 square miles and includes the towns of Conklin and Kirkwood. Multiple small, perhaps discontinuous, valley-fill aquifers of unknown extent and hydraulic interconnection underlie the Susquehanna River valley from easternmost Binghamton south to Riverside, New York, near the Pennsylvania border. The hydrogeologic framework of these aquifers is described in this report on the basis of existing descriptions of surficial materials, especially those related to deglaciation, and subsurface data extracted from well and boring logs. A compilation of surficial geology, the descriptions of the spatial distribution of confined and unconfined aquifers, hydrogeologic sections, and well locations is provided as an oversized map plate and in a U.S. Geological Survey data release. Residential households are one of the principal consumers of groundwater in the study area. Approximately half of these households are served by public water-supply systems that obtain water from wells, chiefly from highly productive but small and likely discontinuous surficial deposits of sand and gravel, while others obtain water from sand-and-gravel aquifers beneath till and (or) fine-grained lacustrine deposits, and a few from bedrock. Residents outside the public-supply service areas rely on private wells. In till-mantled upland areas, nearly all private wells tap bedrock. Water-resource potential is likely greatest north of Kirkwood Center, New York, where the valley is narrowest, and local aquifers are in thick stratified glacial deposits. Well yields are highest in this part of the valley, and the local aquifer system is likely replenished through induced infiltration from the Susquehanna River and numerous small tributaries. The area between Langdon and Kirkwood is filled with a mixture of stratified and unstratified glacial sediments and contains one high-yield well. This area likely has moderate water-resource potential, but limited well data make this difficult to verify. Well yields from suitable stratified glacial sediments generally decrease southward toward Riverside, New York. Characterizing potential groundwater resources is also helpful for prioritizing source-water-protection efforts. Water resources throughout New York are at risk of contamination from commercial and industrial surface activities. As in many valley areas throughout the Susquehanna River watershed in south-central New York, valley wells with depths greater than roughly 100 to 150 feet are susceptible to contamination by naturally occurring saltwater and methane. New York currently has a moratorium on hydraulic fracturing, but the study area is underlain by rocks suitable for unconventional methods of gas production that would likely be initiated if the moratorium were to be lifted.

New York

Areas contributing recharge to selected production wells in unconfined and confined glacial valley-fill aquifers in Chenango River Basin, New York

In the Chenango River Basin of central New York, unconfined and confined glacial valley-fill aquifers are an important source of drinking-water supplies. The risk of contaminating water withdrawn by wells that tap these aquifers might be reduced if the areas contributing recharge to the wells are delineated and these areas protected from land uses that might affect the water quality. The U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation and the New York State Department of Health, began an investigation in 2019 to improve understanding of groundwater flow and delineate areas contributing recharge to 16 production wells clustered in three study areas in the basin as part of an effort to protect the source of water to these wells. Areas contributing recharge were delineated on the basis of numerical steady-state groundwater-flow models representing long-term average hydrologic conditions. In the Cortland study area, four water suppliers operate 10 production wells that withdraw a total average rate of 2,480 gallons per minute from an unconfined aquifer consisting of well-sorted sand and gravel deposits. Simulated areas contributing recharge to these wells at their average pumping rates covered a total area of 6.93 square miles. Simulated areas contributing recharge extend upgradient from the wells to upland till deposits and to groundwater divides. Some simulated areas contributing recharge include isolated areas remote from the wells. Short simulated groundwater traveltimes from recharging locations to discharging wells indicated that the wells are vulnerable to contamination from land-surface activities; 50 percent of the traveltimes were 10 years or less. Land cover in some of the areas contributing recharge included a substantial amount of urban and agriculture land use. The groundwater-flow model of the Cortland study area was calibrated to available hydrologic data by inverse modeling using nonlinear regression. The parameter variance-covariance matrix from model calibration was used to create parameter sets that reflect the uncertainty of the parameter estimates and the correlation among parameters to evaluate the uncertainty associated with the single, predicted contributing areas to the wells. This analysis led to contributing areas expressed as a probability distribution. Because of the effects of parameter uncertainty, the size of the probabilistic contributing areas was larger than the size of the single, predicted contributing area for the wells. Thus, some areas not in the single, predicted contributing area might actually be in the contributing area, including additional areas of urban and agriculture land use that have the potential to contaminate groundwater. Additional areas that might be in the contributing area included recharge originating near the pumping wells that have relatively short groundwater-flow paths and traveltimes. In each of the Greene and Cincinnatus study areas, one water supplier operates three wells that are screened near the top of the bedrock surface in a confined aquifer consisting of poorly to well-sorted sand and gravel deposits. This confined aquifer is overlain by a lacustrine confining unit of very fine sand, silt, and clay, which in turn is overlain by a thin unconfined aquifer of sand and gravel. The groundwater-flow models for these two areas were manually calibrated because of the limited hydrologic data. Simulated areas contributing recharge to the Greene study area wells covered a total area of 0.35 square mile for the average pumping rate of 170 gallons per minute. The contributing areas extended southeastward of the wells to the groundwater divide in the till uplands. The contributing areas also included remote, isolated areas on the opposite side of the Chenango River from the wells primarily in the till uplands. For the Cincinnatus study area wells, which have a low average pumping rate (34 gallons per minute), the simulated contributing areas totaled 0.06 square mile and were on the same side of the river as the wells, but they are isolated areas remote from the wells primarily in the till-covered bedrock uplands. Land cover in these contributing areas for both study areas is primarily agriculture and forested, with the contributing areas to the Greene study area wells also including some urban land uses. Because the Greene and Cincinnatus study area wells are screened relatively deep and some flow paths to the wells partly travel through the confining unit, which impedes the connection with surface sources of recharge, overall groundwater traveltimes are greater than for wells in the Cortland study area. Fifty percent of Cortland study area wells, but only 9 and 44 percent of Greene and Cincinnatus study area wells, respectively, have groundwater traveltimes of 10 years or less.

New York

Hydrogeology of aquifers within the Fairport-Lyons channel system and adjacent areas in Wayne, Ontario, and Seneca Counties, New York

A hydrogeologic investigation was undertaken by the U.S. Geological Survey, in cooperation with the New York State Department of Environmental Conservation, within the areas shown in the Macedon, Palmyra, Newark, and Lyons 7.5-minute quadrangle maps that include parts of Wayne, Ontario, and Seneca Counties in New York. The most productive zone of aquifers within the study area is associated with the Fairport-Lyons glacial-stream channel (hereinafter referred to as the “Fairport-Lyons channel”) in southern Wayne County and adjacent areas. The Fairport-Lyons channel is a west-east-oriented bedrock channel that once served as the outlet for glacial Lake Dawson, which occupied the Genesee Valley near Rochester during the Pleistocene. The Fairport-Lyons channel and intersecting subsidiary channels are hereinafter referred to as the “Fairport-Lyons channel system.” Glacial meltwater eroded this shallow channel network into the underlying bedrock, and the channels subsequently filled with interlayered glaciofluvial sand and gravel and fine-grained lacustrine deposits. These sand and gravel deposits provide the only large supplies of groundwater in Wayne County under unconfined and confined conditions and serve a population of over 20,000 through a combination of domestic and municipal water supply wells. The largest reported well yield, 1,200 gallons per minute, is from an industrial supply well near Newark, N.Y. Much of the sand and gravel within the Fairport-Lyons channel system is generally thinly saturated; however, in three areas—near Macedon, Newark, and Lyons, N.Y.—the saturated thickness of the aquifer is sufficient to support groundwater yields adequate for municipal and industrial use, in part because of induced infiltration from the Erie Canal.

New York

A structured decision-making framework for managing cyanobacterial harmful algal blooms in New York State parks

Cyanobacteria are increasingly a global water-quality concern because of the potential for these organisms to develop into potentially harmful blooms that affect ecological, economic, and public health. Cyanobacterial harmful algal blooms (CyanoHABs) can lead to a decrease in water quality and affect many of the recreational and ecological benefits of parks that include lakes. The New York State Office of Parks, Recreation and Historic Preservation (OPRHP) is a State agency within the New York State Executive Department charged with the operation of State parks and historic sites. Many New York State parks include lakes or other freshwater bodies, which can be susceptible to CyanoHABs. The OPRHP faces difficult decisions regarding prevention of and response to CyanoHABs. The U.S. Geological Survey partnered with the OPRHP and the New York State Department of Environmental Conservation to develop a structured decision-making template for managing CyanoHABs in OPRHP parks. Two parks, Moreau Lake State Park and Rockland Lake State Park, served as case studies to motivate and test the template. This report describes how the principles of structured decision making can be used to navigate the challenges associated with managing CyanoHABs in OPRHP parks. Management objectives and strategies for CyanoHABs in parks are described, strategies to evaluate consequences and manage tradeoffs are discussed, and potential challenges to the implementation of preferred alternatives are considered. General guidance is provided so the OPRHP can undertake the structured decision-making process for CyanoHABs in any of its parks. In addition, this report represents the first effort to create a strategy for applying decision analysis tools to the complex natural resource challenge of CyanoHAB mitigation and management. The case studies and template are intended to serve as an example that natural resource managers faced with CyanoHABs challenges can use to inform their decision-making processes.

New York