R.J. Reynolds 1987 <p>Aquifer diffusivity (transmissivity divided by storage coefficient) was calculated for three sites in a glacial-autwash valley aquifer near Cortland, New York from water-level fluctuations induced by rises in stream stage. The observed response data were analyzed through use of a one-dimensional floodwave-response model to calculate the theoretical head response in the aquifer generated by a floodwave in the stream, and then matched to the observed head response. Diffusivity values computed from sharply peaked flood rises ranged from 6.08 to 8.68 ft². The closest match between observed and calculated heads was obtained from a site where the aquifer is confined and the saturated thickness (and thus the diffusivity) remains constant with the passage of a floodwave. Arrival time of the observed flood-peak seems to be the most useful criterion for curve matching, especially under unconfined conditions, where a match to the rising limb and floodpeak is difficult because of changes in the saturated thickness.</p> application/pdf 10.1111/j.1745-6584.1987.tb02133.x en National Groundwater Association Diffusivity of a glacial-outwash aquifer by the floodwave- response technique article