The Walker Branch Watershed is located on the U. S. Department of Energy's Oak Ridge Reservation in Roane County, Tennessee. Major funding for Walker Branch Watershed research activities comes from the Program for Ecosystem Research (PER) in the DOE Office of Science and Office of Biological and Environmental Research (OBER). The 97.5 ha Walker Branch watershed has been the site of long-term, intensive environmental studies since the late-1960's by staff from the Environmental Sciences Division at Oak Ridge National Laboratory (ORNL), staff from the Atmospheric Turbulence and Diffusion Division, Air Resources Laboratory, National Oceanic and Atmospheric Administration in Oak Ridge, Tennessee, and many visiting university researchers.