An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Polluted Runoff: Nonpoint Source (NPS) Pollution

Monitoring Guidance for Determining the Effectiveness of Nonpoint Source Controls

This nonpoint source monitoring and evaluation guide is written for use by both those who monitor and those who evaluate and fund monitoring proposals. 

The 1997 guidance focuses on monitoring to determine the effectiveness of nonpoint source controls at the watershed and practice levels. A short overview of monitoring design options is followed by detailed sections on biological monitoring, statistical data analysis methods, and quality assurance and control. 

The updated guide: Monitoring and Evaluating Nonpoint Watershed Projects was published May 2016. 

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.