INTEGRATED ASSESSMENT AND ANALYSIS OF PHYSICAL LANDSCAPE PROCESSES THAT IMPACT THE QUALITY AND MANAGEMENT OF AGRICULTURAL WATERSHEDS
Location: Watershed Physical Processes Research Unit
Title: Contributions of RUSLE2 to TMDL development
Submitted to: Environmental and Water Resources Institute World Congress Proceedings
Publication Type: Proceedings
Publication Acceptance Date: March 16, 2012
Publication Date: May 21, 2012
Citation: Dabney, S.M., Yoder, D.C., Renard, K. 2012. Contributions of RUSLE2 to TMDL development. Environmental and Water Resources Institute World Congress Proceedings. pp. 3790-3700.
Interpretive Summary: A Total Maximum Daily Load, or TMDL, is a calculation of the maximum amount of a pollutant that a waterbody can receive and still safely meet water quality standards. The Revised Universal Soil Loss Equation, version 2 (RUSLE2) is conservation planning tool that provides estimates of runoff and sediment delivery from one-dimensional hillslope profiles up to 1000 ft long. The RUSLE2 program can be very useful for TMDL development because it can estimate the relative impacts of various management alternatives on sediment delivery to concentrated flow channels. It advantages include: flexibility to model almost any situation, ease of use, accurate results without calibration, and extensive databases reflecting almost any climate, soil, and management alternative in the US and protectorates. Results of many RUSLE2 hillslope simulations should be combined with a channel erosion and sediment routing model to develop a comprehensive TMDL.
RUSLE2 is a robust and computationally efficient conservation planning tool that estimates soil, climate, and land management effects on sheet and rill erosion and sediment delivery from hillslopes, and also estimates the size distribution and clay enrichment of sediment delivered to the channel system. RUSLE2 is supported by extensive databases maintained by the USDA-Natural Resources Conservation Service. It is commonly accessed through a graphical user interface (GUI) running in a Windows environment, but is also a dynamic-link library (DLL) version that uses the same scientific code and can interact with other computer programs through an application programming interface (API). In addition to average annual erosion and sediment delivery, recent enhancements give RUSLE2 the ability to predict a representative runoff event sequence for a particular location, soil, management, and user-specified return period that can be coupled with a channel erosion and routing model. These features make RUSLE2 applicable to TMDL modeling.