Prepared in cooperation with the New York State Department of Environmental Conservation Hydrogeology of the West Branch Delaware River Basin, Delaware County, New York Scientific Investigations Report 2013–5025 U.S. Department of the Interior U.S. Geological Survey Cover. Groundwater discharging from bedrock fractures exposed in a roadcut of Catskill Mountain Series rocks (upper Walton Formation), Ulster County, New York. Deeper springs emerging from fractures or bedding planes in bedrock are used extensively throughout the Catskill Mountain region for domestic and municipal water supplies, and provide a major contribution to the base flow of streams in the region. Photo by Jason Zatorsky, U.S. Geological Survey, January 2003. Hydrogeology of the West Branch Delaware River Basin, Delaware County, New York By Richard J. Reynolds Prepared in cooperation with the New York State Department of Environmental Conservation Scientific Investigations Report 2013–5025 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2013 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 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Suggested citation: Reynolds, R.J., 2013, Hydrogeology of the West Branch Delaware River basin, Delaware County, New York: U.S. Geological Survey Scientific Investigations Report 2013–5025, 26 p., http://pubs.usgs.gov/ sir/2013/5025/. iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................1 Purpose and Scope ..............................................................................................................................3 Previous Studies ...................................................................................................................................3 Hydrogeology..................................................................................................................................................4 Deglaciation of the West Branch Delaware River Basin ...............................................................4 Surficial Geology ...................................................................................................................................5 Till....................................................................................................................................................5 Colluvium .......................................................................................................................................7 Ice-Contact Stratified Drift .........................................................................................................7 Kames................................................................................................................................... 7 Kame Terraces ....................................................................................................................7 Kame Deltas .........................................................................................................................7 Kame Moraines ...................................................................................................................8 Outwash, Alluvium, and Inwash ................................................................................................8 Outwash................................................................................................................................8 Alluvium ................................................................................................................................8 Inwash ..................................................................................................................................9 Bedrock Geology...................................................................................................................................9 Stratigraphy ..................................................................................................................................9 Structure and Folding ..................................................................................................................9 Faults and Jointing ....................................................................................................................11 Stress Relief Fracturing ............................................................................................................11 Well Yields ...................................................................................................................................11 Saline Groundwater ..................................................................................................................12 Groundwater Flow System .......................................................................................................13 Springs .........................................................................................................................................13 Marcellus Shale .........................................................................................................................15 Stratified-Drift Aquifers .....................................................................................................................17 Upper West Branch Delaware River ......................................................................................18 Middle West Branch Delaware River .....................................................................................18 Lower West Branch Delaware River ......................................................................................19 Precipitation, Runoff, and Evapotranspiration ...............................................................................19 Sources of Stream Base Flow ..........................................................................................................20 Base Flow in Relation to Geology ....................................................................................................22 Bedrock as a Source of Base Flow ........................................................................................22 Thick Till Deposits as a Possible Source of Base Flow .......................................................23 Summary........................................................................................................................................................23 Selected References ...................................................................................................................................24 iv Figures 1. Map showing the location of the West Branch Delaware River Basin in southeastern New York ...............................................................................................................2 2. Map showing distribution of major bedrock units within the West Branch Delaware River Basin in southeastern New York. ..................................................................................10 3. Generalized geologic section showing features of stress-relief fracturing. ...................12 4. Conceptual diagram of groundwater flow within bedrock and stratified-drift aquifers within the West Branch Delaware River Basin in southeastern New York. .....14 5. Graph showing yield of 178 springs in Delaware County, New York, as a function of altitude. ........................................................................................................................................15 6. A, Geophysical log showing typical gamma log response and B, photograph showing typical stratigraphy of the Marcellus Shale in New York. ..................................16 7. Map showing the distribution of mean annual precipitation and runoff for 1951–80 within the West Branch Delaware River Basin .....................................................................20 Tables 1. Thickness of and depth to the Marcellus Shale in selected deep test holes in Delaware County, New York .....................................................................................................17 2. Hydrogeologic characteristics of 13 Catskill drainage basins within the Delaware River Basin in southeastern New York ....................................................................................21 v Conversion Factors and Datum Inch/Pound to SI Multiply By To obtain Length inch (in.) 2.54 centimeter (cm) foot (ft) 0.3048 meter (m) mile (mi) 1.609 kilometer (km) Area square mile (mi2) 2.590 square kilometer (km2) Flow rate cubic foot