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Drinking Water Requirements for States and Public Water Systems

SWTR Plain English Guide

The purpose of this guide is to describe how the Suite of Surface Water Treatment Rules (SWTRs) apply to different types of public water systems (PWSs) based on the type of filtration used and the population of the PWS (or combine distribution system (CDS) population). The SWTRs covered by this guide include:

• Surface Water Treatment Rule (SWTR) – June 1989

• Interim Enhanced Surface Water Treatment Rule (IESWTR) – December 1998

• Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) – January 2002

• Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) – January 2006

• Filter Backwash Recycling Rule (FBRR) – June 2001

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  • SWTR Plain English Guide (PDF)(87 pp, 1 MB, 6/17/2020, 815R20006)
    The purpose of this guide is to describe how the Suite of Surface Water Treatment Rules (SWTRs) apply to different types of public water systems (PWSs) based on the type of filtration used and the population of the PWS (or combine distribution system (CDS) population). The SWTRs covered by this guide include:Surface Water Treatment Rule (SWTR) – June 1989