Estimated Effects of Ground-Water Withdrawals on Streamwater Levels of the Pleasant River near Crebo Flats, Maine, July 1 to September 30, 2005

Surface-water data collected at two streamflow-gaging stations on the Pleasant River were analyzed to determine whether ground-water withdrawals from an irrigation well near the Pleasant River have affected streamflows. The relation between the stream-stage data from the two stations shows that stream stage on days when the well was pumped differs from stream stage on days with no pumping, indicating that short-term streamflow depletion occurred. The linear relation defining the relation of stage at the two gaging stations during periods of pumping is significantly different from the linear relation defining the relation of stage at the same two stations during periods of no pumping. The difference between the two linear relations was used to estimate how much short-term streamflow depletion is coincident with ground-water withdrawals. Estimated short-term streamflow depletion varies with stage and ranges from approximately 0.3 to 0.8 cubic feet per second; the relative short-term streamflow depletion ranges from approximately 1.7 to 10 percent.