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Clean Water Act Analytical Methods

Other Clean Water Act Test Methods: Microbiological

Not Approved Under 40 CFR Part 136

Photo of viruses and sample preparationIn addition to developing and approving methods for use in compliance monitoring, EPA may develop methods to support studies of specific industries (e.g., the Effluent Guidelines program) or for use in broad national surveys. If such studies or surveys lead to regulatory limits of new contaminants, EPA approves the applicable methods for nationwide or industry-specific use through rulemaking which includes an opportunity for public comment.
Although the following methods are not in EPA regulations, they may be of interest to regulated entities, permitting authorities, and the public. The presence of a method here does not imply a regulatory requirement for its use.

Microbial Source Tracking Methods

In response to stakeholders’ needs for validated methods for microbial source tracking (MST) to characterize human sources of fecal pollution in recreational waters, EPA conducted a multi-laboratory validation study to assess method performance of Methods 1696 and 1697 across 14 laboratories in fresh and marine recreational water matrices.

Currently, there is a great deal of interest in Methods 1696 and 1697 in the United States and worldwide. EPA anticipates that stakeholders will use these methods to identify trends in human fecal contamination, to provide additional information to support water quality management decisions, and to help determine actionable outcomes that can potentially improve public health protection of fresh and marine recreational waters.

Other Microbiological Methods

Calculation Spreadsheets for Methods

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