SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Application of a watershed model to evaluate management effects on point and nonpoint source pollution 
Authors:Santhi, C., J.G. Arnold, J.R. Williams, W.A. Dugas, and L. Hauck 
Journal:Transactions of the ASAE 
Article ID: 
URL (non-DOI journals):https://wiki.umn.edu/pub/Nieber/AssessmentDiagnosisOfImpairedWaters/santhi_-_appl_of_watershed_model_for_management_effects_on_npsp.pdf 
Broad Application Category:hydrologic & pollutant 
Primary Application Category:pollutant cycling/loss and transport 
Secondary Application Category:none 
Watershed Description:4277 km^2 Bosque River (north central Texas) 
Calibration Summary:results repeated from Santhi et al. 2007 
Validation Summary:results repeated from Santhi et al. 2007 
General Comments:Ten scenarios consisting of dairy and/or waste water treatment plants (WWTPs) were evaluated to determine the impacts on soluble P concentrations at 3 locations on the Bosque River during 1960-89. The WWTP scenarios resulted in greater improvement in time-weighted concentrations, but dairy BMPs were found most effective in reducing flow-weighted concentrations. 
Abstract:A Total Maximum Daily Load (TMDL) program has been initiated in the North Bosque River Watershed in Texas, USA, where point and nonpoint sources of pollution are of a concern. The Soil and Water Assessment Tool (SWAT), which had been validated for flow and sediment and nutrient transport, was applied to quantify the effects of Best Management Practices (BMPs) related to dairy manure management and municipal wastewater treatment plant effluent. Results are presented for the period from 1960 through 1998 for three sites along the North Bosque River. Results are presented as annual time–weighted concentrations (average of the daily load divided by daily flow over a year) and annual flow–weighted concentrations (total cumulative load divided by total cumulative flow over a year). The wastewater treatment plant BMPs resulted in greater improvement in time–weighted instream soluble phosphorus concentrations than dairy BMPs. On the other hand, dairy BMPs made greater differences in flow–weighted concentrations. This study showed that SWAT could be a useful tool for studying the effects of alternative management scenarios for pollution control from point and nonpoint sources in large watersheds. 
Keywords:Watershed management, Water quality, Nonpoint source pollution, Point source pollution, Dairy manure management, Municipal wastewater treatment plants, Best management practices, Total maximum daily load