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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. 

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