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Tribal Utilities Role in Safe Drinking Water on Tribal Lands

Tribal Utility SDWA Compliance

Compliance with Drinking Water Regulations

National Primary Drinking Water Regulations (NPDWRs) are legally enforceable standards that apply to public water systems. These standards protect public health by limiting the levels of contaminants in drinking water.

EPA regulations also:

  • Set testing and recording requirements; and
  • List acceptable techniques for treating contaminated water

It is your responsibility as a tribal utility organization to comply with the NPDWRs. In the absence of tribal primacy, EPA has primary enforcement responsibility under the SDWA in Indian country.

Federal drinking water regulations apply to all public drinking water systems throughout the country regardless of ownership or primacy agency. Therefore, the same principles and guidelines apply to all public water systems, including those in Indian country.

Under the National Primary Drinking Water Regulations, public water system owners and operators are responsible for:

  • Monitoring their systems;
  • Reporting compliance; and
  • Providing public notice.


Public water systems are required to monitor their water regularly for contaminants. EPA can provide technical assistance to show utility operators how to properly sample and monitor a public water system.

EPA cannot perform actual on-site sampling or any activity related to compliance monitoring. Operators must carry out these activities.


The water system must report to the primacy agency the results of water samples to demonstrate that the water meets health based standards.

Public Notification

Water systems must provide public notification to persons served by the water system. Three tiers:

  • Tier 1 public notice—required for NPDWR violations and situations with significant potential to have serious adverse effects on human health as a result of short-term exposure.

  • Tier 2 public notice—required for all other NPDWR violations and situations with potential to have serious adverse effects on human health.

  • Tier 3 public notice—required for all other NPDWR violations and situations not included in Tier 1 and Tier 2.

For more information on monitoring water systems and reporting compliance data, please refer to EPA’s Monitoring, Assessment and Reporting Guidelines.