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About the Safe Drinking Water Act

The Safe Drinking Water Act (SDWA) is federal law that protects Americans' drinking water quality. Under SDWA, EPA sets standards for drinking water quality for both natural and man-made contaminants.  EPA oversees states, localities and water suppliers implementing those standards and protecting water sources.

Millions of Americans receive high quality drinking water every day from their public water systems.  Communities’ public water systems may be publicly- or privately-owned.

While the United States has drinking water standards protective of public health, threats still exist. Threats to drinking water quality and safety may include: 

  • Improperly disposed of chemicals
  • Animal wastes
  • Pesticides
  • Human Wastes
  • Wastes injected deep underground
  • Naturally-occurring substances
  • Drinking water not properly treated or disinfected
  • Drinking water transmitted through an inadequately maintained distribution system

How does EPA provide drinking water quality protection?

EPA sets standards to protect public health through:

  • The Law, which provides Congress’ direction to protect public health through drinking water regulation.
  • Regulations provide specific standards and steps to be taken to comply with the law. 
  • Guidance gives states and water system operators information to assist them in applying the standards.

SDWA law, regulations and guidance provide steps to respond to contaminants ocurring in drinking water sources.