Water Resources Research Act Program

Details for Project ID 2008WI192B

A Thermal Remote Sensing Tool for Mapping Spring and Diffuse Groundwater Discharge to Streams

Institute: Wisconsin
Year Established: 2008 Start Date: 2008-03-01 End Date: 2009-02-28
Total Federal Funds: $34,190 Total Non-Federal Funds: $29,485

Principal Investigators: Steven Loheide

Project Summary: This research will be a proof-of-concept for using Unmanned Aerial Vehicles (UAVs) to collect thermal remote sensing data for mapping of groundwater discharge. The premise of the work is that the thermal signature of groundwater is relatively constant year round, but differs from the stream temperature which varies on diel and annual cycles. The approach implemented in this work will be to collect thermal imagery at the stream reach scale (several kms), at four times during the day dawn, noon, 4pm, and dusk. From this imagery, springs will be visually identified and discharge rates estimated from the amount of cooling/warming observed. Diffuse flow will be identified by creating longitudinal profiles of stream temperature and locating subreaches with depressed maximum diel stream temperature and increased minimum diel stream temperature. Maps of both spring and diffuse groundwater discharge will be created that aid in 1) understanding of stream-aquifer interactions 2) providing insight into the underlying groundwater flow system 3) identifying reaches where groundwater discharge may threaten surface water quality through discharge of contaminated groundwater 4) developing a water quality monitoring program that can account for areas of known discharge and 5) targeting reaches for conservation or restoration where stream-aquifer interactions are favorable for supporting aquatic ecosystems. This research will improve our understanding of stream-aquifer interactions. In addition, this work will provide a cost-effective, transferable methodology for identification and mapping of springs, a research priority that would support implementation of the 2003 Wisconsin Act 310.