New York Water Science Center
Problem - The valley-fill deposits in Upper Buttermilk Creek/Danby Creek valleys are sources of water for many homeowners, farms, and small businesses that are in this valley. The aquifer was mapped by Miller (2000) and identified as one of the 17 aquifers in Tompkins County that needs to be studied in more detail. However, there is little geohydrologic data in the valley. A cluster of wells in Upper Buttermilk valley are finished in sand and gravel, indicating that there is a sand and gravel aquifer in, at least, part of the valley. The Upper Buttermilk Creek/Danby Creek valleys are "through valleys"-- a part of a valley where the bedrock floor rose to land surface and formed a preglacial surface-water divide. The divide became scoured by glaciers and the valley became subsequently filled in with glacial drift that was deposited during deglaciation (Randall, 2001). In some through valleys, including the one is this study area, the glacial drift forms a watershed divide at, or near, the former bedrock divide. Through valleys are special geohydrologic settings because they contain a relatively wide valley in which large amounts of stratified drift were deposited, but are drained by tiny headwater streams. These streams are called "misfit streams" because they're proportionally small for the size of the valley. These small streams are sensitive to hydrologic stresses in the through valley; for example, they may dry up quickly due to periods of drought conditions or by pumping wells.The objective of the proposed study is to improve the understanding of the geohydrology of the valley-fill deposits in the Upper Buttermilk Creek/Danby Creek valleys in the Town of Danby, Tompkins County. Specifically, the study will provide the following geohydrologic information: (1) extent and thickness of geohydrologic units, (2) hydraulic conditions in the aquifers- whether the units are confined (artesian) or unconfined, (3) extent of ground water/surface-water interaction, (4) ground-water use (type and amount of ground-water withdrawal), (5) water levels in geohydrologic units and the direction of ground-water flow, and (6) general water quality of the aquifers.
Approach - Geohydrologic data will be collected and maps will be compiled that depict the (1) aquifer boundaries and (2) generalized geologic framework, recharge areas, potentiometric surface, and direction of ground-water flow in the aquifers. A report will describe general aquifer characteristics and ground-water/surface-water interactions. Individual work elements include; 1) inventory wells in the valley, 2) seismic-refraction surveys, 3) test well drilling, 4) constructing geohydrologic sections showing the glacial stratigraphy of the deposits and aquifer boundaries, 5) ground-water-level measurements that will be used to construct generalized potentiometric-surface map, and 6) stream gain/loss measurements will be made in tributaries and in Buttermilk and Danby Creeks to determine reaches where ground water either discharges into the stream or is recharged by water seeping from the stream into the ground. In addition, in selected wells, water quality samples will be collected and analyzed for common ions and nutrients.