ANALYSIS OF TIME-SERIES MEASUREMENTS OF SEDIMENT TEMPERATURE FOR IDENTIFICATION OF GAINING VS LOSING PORTIONS OF JUDAY-CREEK, INDIANA

Identifying locations at which groundwater and surface water interact can be important in a variety of contexts including the development of water budgets, the determination of migration pathways for nutrients and contaminants, and the estimation of thermal budgets along small water bodies. Some difficulty has been experienced in identifying locations of inflows over large regions when detailed groundwater information is not known. A method is suggested herein for the identification of the location of inflows-outflows in both creeks and streams. This method, applied to a small creek in northern Indiana, involves measurement over time of both the sediment temperature and the temperature at the base of the overlying water column. The results are used to define reaches along the creek which are gaining and reaches along the creek which are losing. These results are supported by independent measurements of groundwater elevations at several points along the stream. It is argued that this method provides an excellent screening tool for the identification of gaining and losing reaches of small waterways.