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Drinking Water Requirements for States and Public Water Systems

Long Term 1 Enhanced Surface Water Treatment Rule Documents

The Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) builds on the requirements of the Surface Water Treatment Rule and specifies treatment requirements to address Cryptosporidium m and other microbial contaminants in public water systems serving less than 10,000 persons.

The rule balances the need for treatment with potential increases in disinfection by -products. The materials found on this page are intended to assist public water systems affected by the LT1ESWTR comply with the regulation and in state implementation of the LT1ESWTR. 

SWTR/LT1 Monitoring Requirement Placards


For more information, please see the Surface Water Treatment Rules page.

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