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Tribal Public Water System Supervision Program

Program Overview

In the 1974 Safe Drinking Water Act (SWDA), Congress authorized the Public Water System Supervision (PWSS) program. The purpose of the PWSS is to establish, implement, and enforce health protection standards for drinking water systems that serve the public.

The goal of the program is to protect public health by ensuring that drinking water systems maintain or achieve compliance with new and existing drinking water regulations.

The 1986 amendments to the SDWA allow Indian tribes to be treated as states and assume PWSS primacy if they meet the necessary requirements.

  • The Navajo Nation has primacy over 170 public water systems on their lands.

  • The State of Alaska has primacy over approximately 200 public water systems serving Alaska Native Villages (ANV).

In cases where tribes do not assume primacy, EPA serves as the primacy agency and implements the PWSS program. There are over 1,000 public water systems serving over 1 million people in Indian country where the EPA has primacy responsibilities.

In addition to implementing and enforcing regulations, PWSS program activities include:

  • Providing oversight and technical assistance to systems;
  • Conducting sanitary surveys; and
  • Managing data reported by systems.

For more information, please refer to the Tribal PWSS Program Grants Fact Sheet and the Final 2008 Tribal PWSS Guidance. EPA currently uses this guidance to provide direction on the uses, allowances, and limitations associated with PWSS funds that are reserved to support the tribal PWSS program. 

Program Eligibility Requirements

The 1986 amendments to the SDWA authorize EPA to make grants to tribes that want to develop and carry out PWSS programs. In 1989, EPA began directing funds to carry out the PWSS programs on tribal lands. These funds are used in:

  • Grants to tribes that have assumed PWSS primacy;
  • Activities that help tribes develop programs leading to primacy; and
  • Assistance to EPA Regional Offices for direct implementation of PWSS on tribal lands where EPA has primacy.

To be eligible to receive a grant from this fund, a federally-recognized tribe must have primacy over their PWSS program or have been granted “Treatment in the Same Manner as a State (TAS)” as provided for in the SDWA §1451.

Annual Allocation

Every year, Congress appropriates funds for EPA to provide grants to eligible states, territories and tribes to carry out PWSS programs.

The funds are allocated to EPA Regional Offices and other eligible primacy agencies (for example, Navajo Nation) based on a formula, which takes into account the:

  • Tribal population;
  • Tribal land area; and
  • Number of water systems located within tribal boundaries.

View the Final Allotments for the FY2017 Public Water System Supervision (PWSS) State and Tribal Support Program Grants.

Access Tribal Drinking Water Program Fund Allotments historical data.

Program Contacts

Please contact your Regional Tribal Drinking Water Direct Implementation Coordinators for more information on:

  • Tribal PWSS program;
  • Other direct implementation activities; and
  • EPA work with tribes to directly implement the PWSS program in your area.