Geohydrology and Water Quality of Stratified-Drift Aquifers in the Winnipesaukee River Basin, Central New Hampshire By JOSEPH D. AYOTTE U.S. Geological Survey Water-Resources Investigations Report 94-4150 Prepared in cooperation with the NEW HAMPSHIRE DEPARTMENT OF ENVIRONMENTAL SERVICES WATER RESOURCES DIVISION Pembroke, New Hampshire 1997 Estimation of Water Availability for Selected Aquifers.............................................................................................. 31 Model Construction........................................................................................................................................... 31 Model Input Parameters.................................................................................................................................... 32 Position of the Water Table..................................................................................................................... 32 Saturated Thickness and Hydraulic Conductivity................................................................................... 32 Specific Yield.......................................................................................................................................... 32 Streambed Hydraulic Conductivity......................................................................................................... 32 Results of Ground-Water Availability Estimates .............................................................................................. 33 Merrymeeting River Aquifer................................................................................................................... 33 Pumping Station Brook Aquifer.............................................................................................................. 36 Ground-Water Quality........................................................................................................................................................... 39 Specific Conductance.................................................................................................................................................. 39 Dissolved Solids........................................................................^ 39 pH......................................................_ 39 Alkalinity..................................................................................................................................................................... 42 Calcium, Magnesium, and Hardness........................................................................................................................... 42 Sodium and Chloride................................................................................................................................................... 43 Nittate...............................................................^ 44 Sulfate.......................................................................................................................................................................... 44 Iron and Manganese.................................................................................................................................................... 44 Trace Elements............................................................................................................................................................ 44 Summary and Conclusions.................................................................................................................................................... 45 Selected References...............................................................................~^ 46 Glossary..................................................................................................................................................................^ 50 Appendixes A. Description of selected wells, borings, and springs in the Winnipesaukee River Basin, central New Hampshire................................................................................................................................. 55 B. Stratigraphic logs of selected wells and borings in the Winnipesaukee River Basin, central New Hampshire................................................................................................................................. 93 C. Geohydrologic sections interpreted from seismic-refraction data, central New Hampshire.................................. 159 D. Low streamflow measurements at miscellaneous sites in central New Hampshire............................................... 183 E. Monthly water levels at selected wells, central New Hampshire........................................................................... 189 PLATES [Plates are in pocket] 1-4. Maps showing aquifer boundaries, data-collection locations, materials, and altitude of water table for stratified-drift aquifers in the Winnipesaukee River Basin, central New Hampshire: 1. Southwestern part 2. Southeastern part 3. Northwestern part 4. Northeastern part 5-8. Maps showing saturated thickness, transmissivity, and materials of stratified-drift aquifers in the Winnipesaukee River Basin, central New Hampshire: 5. Southwestern part 6. Southeastern part 7. Northwestern part 8. Northeastern part IV Contents FIGURES 1. Map showing location of study area and towns in the Winnipesaukee River Basin, central New Hampshire......................................................................................................^ 3 2. Sectional diagram of an ice-dammed glaciolacustrine deltaic aquifer....................................................................... 6 3. Block diagram of the formation of a glaciofluvial deltaic aquifer............................................................................. 7 4. Map showing maximum extent of glacial-lake environments in the Winnipesaukee River Basin, central New Hampshire.............................................................................................................................................. 9 5. Hydrograph showing long-term water levels at observation well FKW-1 in stratified drift, central New Hampshire.............................................................................................................................................. 14 6. Map showing locations of selected long-term streamflow-gaging stations in and near the Winnipesaukee River Basin, central New Hampshire.......................................................................................... 16 7, 8. Diagrams showing: 7. Ground-water flow and water-level drawdowns at a withdrawal well near an impermeable boundary...................................................................................................................................... 17 8. Ground-water flow and water-level drawdowns at a withdrawal well near a recharge boundaiy............................................................................................................................................^ 18 9. Graph showing relation between estimated hydraulic conductivity, median grain size, and degree of sorting of stratified drift in New Hampshire........................................................................................ 20 10. Map showing general locations of selected aquifers in the Winnipesaukee River Basin, central New Hampshire.............................................................................................................................................. 22 11-14. Geohydrologic sections through the: 11. Pumping Station Brook aquifer, Belmont, New Hampshire ............................................................................. 23 12. Gunstock River aquifer, Gilford, New Hampshire............................................................................................ 26 13. Merrymeeting River aquifer, Alton, New Hampshire....................................................................................... 27 14. Hawkins Brook aquifer, Meredith, New Hampshire......................................................................................... 29 15-18. Map showing model boundary, surface-water boundaries, hypothetical wells, and drawdown contours for the; 15. Merrymeeting River aquifer, central New Hampshire with simulation of induced infiltration............................................................................................................................................. 34 16. Merrymeeting River aquifer, central New Hampshire with simulation of no induced infiltration............................................................................................................................................. 35 17. Pumping Station Brook aquifer, central New Hampshire with simulation of induced infiltration............................................................................................................................................. 37 18. Pumping Station Brook aquifer, central New Hampshire with simulation of no induced infiltration............................................................................................................................................. 38 TABLES 1. Two-letter town codes used as prefixes in the numbering system for wells, borings, and springs in the Winnipesaukee River Basin, central New Hampshire ..................................................................... 5 2. Percentage of flow duration on July 3, 1991, for selected U.S. Geological Survey streamflow-