Purpose and scope: The purpose of this report is to quantify the base flow of 19 continuously gaged Long Island streams during 1960-75, which includes the 1962-66 drought. These base-flow data will be used in calibrating computer models designed to predict the response of Long Island streams to hydrologic stresses such as the lowering of ground-water levels in response to large-scale sanitary sewering. The data will also be used to assess the long-term impact expected to result from storm- and sanitary-sewer systems on base flow of streams.

This report uses a digital model to predict the projected increase in ground-water use caused by a population influx for September 1976 in Cortland, New York. It contains maps, tables, and other figures.

From purpose and scope: This report is the first in a three-part series describing the U.S. Geological Survey's efforts in the detailed hydrologic investigation of southern Nassau and southwest Suffolk Counties, which includes a ground-water modeling study to predict the effects of an extensive sewer network scheduled to be completed in 1985. As the introduction to the series, this report has four objectives: (1) to present a detailed description of the hydrologic system in the area, including newly acquired hydrogeologic information; (2) to define the hydrogeologic factors that will be affected by the sewer network; (3) to explain the modeling strategy and describe the techniques used to develop the ground-water models of the two adjacent areas studied; and (4) to present a preliminary evaluation of the effects of sewers as predicted by a regional ground-water flow model.

Purpose and scope: The Meadowbrook artificial-recharge project, a cooperative effort between the U.S. Geological Survey and the Nassau County Department of Public Works (NCDPW) since 1975, is intended to demonstrate the feasibility of using reclaimed wastewater to replenish and improve the quality of Long Island's ground water. This report presents the results of geologic, hydrologic, and hydrochemical studies that were done at the Meadowbrook artificial-recharge site to define conditions prevailing before the start of recharge operations.

Purpose and scope: This report discusses the design, theory of operation, performance characteristics, and sampling implications if the inclined gravity lysimeter. This variation of a gravity lysimeter can be constructed to maximize capture efficiency and eliminate artificial filtration and is used most successfully in coarse, moist soils where access for installation is from a trench or observation manhole.

From abstract: Channel-routing models were used to route hypothetical releases from reservoirs in the upper Tioga River basin, Pennsylvania. These releases were routed northward down the Tioga River to Lindley, Erwins, and Corning, New York; combined with flows routed down the Cohocton River from Campbell to Corning, New York; and then routed southeastward down the Chemung River from Corning to Chemung, New York. The models used to route the flows of Cohocton and Chemung Rivers accounted for bank-storage discharge and streamflow depletion by well pumpage. In general, 17 years of concurrent streamflow data were available for model calibration and verification.

This report evaluates six public water-supple systems in Schenectady County to create a recommendation of how to monitor these sites. It contains maps and tables.

From abstract: "Water samples from two Hudson River floods in 1977--one originating mainly in shale sub-basins that produce high sediment loads, the other in soil-poor, crystalline rock terrane that yields little sediment--were analyzed to evaluate the relationship of iron, manganese, lead, phosphorous, and polychloride biphenyle (PCB's) to suspend-sediment concentration."

Abstract: A facility consisting of a circular recharge basin 6.10 meters in diameter with a central observation manhole was developed on Long Island to study the role of the unsaturated zone during aquifer recharge with tertiary-treated sewage. The manhole extends through most of the 7.5-meter-thick unsaturated zone, which is composed of glacial outwash sand and gravel, and enables collection of water samples and monitoring of dynamic characteristics of the unsaturated zone during recharge experiments. The system contains instrumentation for monitoring infiltration rate, pressure-head distribution, soil-moisture content, ground-water levels, and soil gases. The 24.55-square-meter recharge basin has operated in all seasons intermittently since April 1975 and, as of April 1978, has transmitted 62 million liters of tertiary-treated effluent to the water-table aquifer. Overall performance of the facility indicates that it is suitably designed for monitoring the unsaturated zone during artificial-recharge experiments.

From purpose and scope: This report describes the interaction between river water and the river-bottom deposits above Troy and provides estimates of the yearly transport rate of PCB's from the study reach into the Hudson River estuary.

From abstract. This report examines flow-duration curves for nine streams in Nassau and Suffolk Counties to evaluate effects of urbanization on streamflow patterns in New York. It contains a map, graphs, and tables.

This report presents the analysis of "data from three two-day aquifer tests of the unconfined aquifer (water-table_ aquifer in southern Nassau Count, Long Island, during the autumn of 1979.

This report presents the results of a preliminary investigation into the water quality and the relationship between surface and ground-water for the Connetquot Brook basin in Long Island, New York. It contains maps, graphs, and tables.

Purpose and scope: This report depicts in detail the areal extent, altitude, thickness, and lithology of the "20-foot" clay and Gardiners Clay (the two thickest and most extensive near-surface confining layers in the area) and redefines the surface of the geologic units that directly underlie these clay units at various locations--the Matawan Group-Magothy Formation, undifferentiated, the Monmouth Group, and the Jameco Gravel.

Abstract: Unconsolidated strata of clay, silt, sand, and gravel of Late Cretaceous and pre-Wisconsin Pleistoscene ages lie between crystalline basement rocks (bedrock) of Precambrian (?) age and unconsolidated deposits of late Pleistocene (Wisconsin) and Holocene ages in Queens County, Long Island, N.Y., a borough of New York City. Data collected during a recent study of the hydrogeology of the county and updated records of earlier studies have been used to prepare contour maps that delineate the surfaces of the bedrock and the Upper Cretaceous and pre-Wisconsin Pleistocene deposits. The presence of diabase fragments, apparently from the Hudson Palisades, in a buried valley through the county suggests that the ancestral Hudson River was diverted into Queens County in Pleistocene.

From purpose and scope: The study was made to obtain baseline data for the island (Shelter Island) and as part of a larger study of shallow ground-water quality in Suffolk County, New York.

Abstract: The Tioga River and its major tributaries were sampled monthly from September 1973 to May 1975. Water quality in the Tioga River is degraded by acid-mine drainage entering the stream near Blossburg from both strip- and deep-mined areas. The stream supports few species of aquatic life from Blossburg to its confluence with Crooked Creek- Alkaline water of tributaries Mill Creek, Crooked Creek, and the Cowanesque River counteract the acidity carried downstream from Blossburg, and ·the water-quality of the Tioga River gradually improves, supporting a more diversified population of fish and aquatic life. Relationships between selected water-quality parameters have been developed for the sampling stations throughout the basin. Downstream trends were also examined. The relationships will be further refined and implemented in predictive water-quality models as more data are collected.

From abstract: "Flow-routing models were developed for six reaches of major streams in the eastern Susquehanna River basin in New York State and were used to trace releases of water from East Sidney Lake and Whitney Point Lake to gaged points downstream." It includes maps, graphs, and tables.

Abstract: Concentrations of nitrate, chloride, and total sol ids in water in the Magothy aquifer, southeast Nassau County, N.Y., show a steadily increasing trend from the early 1950's to 1973. Vertical distribution of nitrate, chloride, and total-solids concentrations as shown in sections of the study area indicate downward movement of these constituents. Maximum concentrations are in a zone underlying the areas of Westbury, Hicksvil.le, and Plainview. Nitrate (as nitrogen) concentration increased from 4-5 milligrams per liter to 7 milligrams per liter in the area of Westbury and from 3 to 10 milligrams per liter in Plainview during the period 1950-73. During this same period, a 10 milligram-per-liter line of equal-chloride concentration on a cross section in the Westbury area moved downward a distance of less than 50 feet (15 meters), and in the area of Hicksville nearly 150 feet (45 meters). Total-solids concentration doubled in the area of Plainview, where maximum downward movement of pollutants was observed.

From purpose and scope: The purpose and scope of this report is to present the factors that have caused the water-table rise in the East New York section of Brooklyn. The rising water table in Kings County is not sudden or new; it has a history of more than two decades. It will refocus attention on the problem of changing ground-water levels in areas where intensive ground-water pumping has ceased or is occurring.

Purpose and scope: This report describes (1) methods of computation used to obtain the daily lake inflows and outflows and river discharges; (2) sources of error and their implications for reliability of the computed values; and (3) a technique for smoothing lake-level hydrographs that minimizes the effect of random fluctuations in daily lake-levels resulting from seiche or wind action.

Purpose and scope: This report presents results from an evaluation of geologic data collected and compiled as part of a continuing investigation and appraisal of hydrologic conditions in Suffolk County. The investigation is part of a cooperative program of water-resources studies made by the U.S. Geological Survey in cooperation with the Suffolk County Water Authority and the Suffolk County Department of Health Services.

From abstract: This report studies the covers over radioactive waste burial trenches in New York; it describes the results of "measurements of atmospheric pressure and the differential pressure between the trench gas and the atmosphere" over a two year period. It contains maps, graphs, and tables.

Report and geographical survey. This report investigates the "steady increase in the chloride and nitrate content of the water" within a glacial aquifer in the Cortland area. Includes several maps and figures.