DETERMINING STREAM DISCHARGE LOCATIONS USING UAV BASED THERMAL IMAGERY

Small unmanned areal systems (sUAS) have recently become more prevalent in environmental remote sensing. With the advent of small inexpensive recording thermal imagers, a wide variety of local scale investigations becomes possible. Spatial resolution from sub-meter down to a few centemeters is achievable based on flight elevations. In this study, a FLIR Vue thermal imaging camera attached to a quadcopter sUAS system is used to map thermal variations in a small urban river, The Ottawa River in NW Ohio, in order to identify potential discharge areas into the creek from both mapped and unmapped discharge pipes and groundwater discharge. Flights occured from in Jan-July 2017, at low and high flow, to determine optimal conditions to identify discharge events. Low cost, rapid identification of thermal anomalies in stream temperature provide a screening tool usable in identifying discharge locations.