BRIDGES Trainee’s Internship with Desert Research Institute

Image: Example of preliminary results of the IrrMapper automated irrigation mapping system under development at the University of Montana.

David Ketchum, 3rd year PhD student in the UM W.A. Franke College of Forestry and Conservation recently completed his internship with Justin Huntington, PhD, associate research professor of hydrology at the Desert Research Institute, a nonprofit research campus of the Nevada System of Higher Education. David’s research focus is on the water resource impacts of irrigation in the western United States. David uses sophisticated remote sensing methods to map crop evapotranspiration at high resolution at regional scales for the State of Montana Department of Natural Resources. David and Justin teamed up to work on mapping where irrigation is being used across the western US. They first compiled a large geodatabase of mapped land cover examples including irrigated and rainfed fields, uncultivated lands, and wetlands. They extracted large amounts of gridded Landsat satellite images, meteorology, climate, and terrain data for those areas. They then used a machine learning algorithm to train a land use classifier, using the compiled gridded data, that identifies irrigated lands each year for the period 1986 – 2018 at 30 m resolution over the entire western US (IrrMapper). This data is now being incorporated into the database powering the OpenET project (, a cutting-edge web platform where users will be able to view agricultural water use data quickly, across the US, at the field scale. David and Justin are currently working with David’s adviser, Kelsey Jencso, on a publication to present their results.