case studies

U.S. Department of Agriculture (USDA):
Tennessee water availability for agriculture





USDA – TN water availability for Agriculture

CAESER is partnering on a USDA grant with the University of Tennessee at Knoxville, University of Tennessee at Martin, Austin Peay State University and Middle Tennessee State University to focus on the long-term availability of water for agricultural production with projections to 2050. Five watersheds were chosen for our investigation: three of them in Middle and East Tennessee (karst) and two in West Tennessee (unconsolidated sediment).

Our initial modeling was for the Hiwassee watershed in East Tennessee. Here agriculture relies primarily on surface water and groundwater would only be used to supplement surface water withdrawals during drought periods. The geology of this watershed is very complex, consisting of folded rock and compartmentalized flow. Unfortunately, not enough hydrogeologic data exists for this area, or for the other two karst watersheds.

We have turned our attention to the two watersheds in West Tennessee. Unlike Middle and East Tennessee, West Tennessee agriculture relies on groundwater for most of its irrigation rather than surface water. As the two watersheds share a common boundary, a single groundwater model will be developed. Parameters from a regional groundwater model, MERAS (Mississippi embayment regional aquifer study), developed by the U.S. Geological Survey will be used to build the starting conditions of our model. Stressors such as recharge, evapotranspiration and surface water interaction will be provided by the other research team members. An improved form of coupling the groundwater and surface water will be a key focus.