U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PubAg

Main content area

Application of a Watershed Model to Evaluate Management Effects on Point and Nonpoint Source Pollution

Author:
Santhi, C., Arnold, J.G., Williams, J.R., Hauck, L.M., Dugas, W.A.
Source:
Transactions of the ASAE 2001 v.44 no.6 pp. 1559-1570
ISSN:
0001-2351
Subject:
Soil and Water Assessment Tool model, animal manure management, best management practices, dairy manure, municipal wastewater, nonpoint source pollution, nutrient transport, phosphorus, pollution control, rivers, sediments, total maximum daily load, wastewater treatment, watersheds, Texas
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.
Agid:
3154507