A HYDROLOGICAL MODEL OF WABASH WATERSHED FOR ASSESSING AND MANAGING WATER RESOURCES IN INDIANA

The Wabash drainage basin covers about 70% of the State of Indiana and provides critical ecoservices to the state and neighboring states. To better prepare for the projected climate changes in this century, a semi-distributed, watershed-scale model was developed for the entire Wabash basin using the USDA’s Soil & Water Assessment Tool (SWAT). Specifically, data and information on elevation, land cover & use, and soil type were used to delineate the watershed and sub-watersheds; and daily weather data (such as precipitation and temperature) were input to drive the model, which then simulated and quantified river flows and other key hydrologic processes, including evapotranspiration, surface runoff, infiltration, and recharge to aquifers. The model has been calibrated to discharge data collected at four U.S. Geological Survey gaging stations in the downstream portions of the basin from 2003-2009 and validated with the 2010-2013 discharge data at the same locations. We are now collaborating with atmospheric scientists to use downscaled climate modeling data to simulate the changing hydrological cycle through 2100. Results on a changed hydrological cycle under various climate change scenarios in 2050 and 2100 will form a basis for evaluating strategies for preparing for environmental changes, such as water resources management, flood forecasting, wildlife migrations as well as social and economic analyses.