Governance & Policy
US Clean Water Act
The principal United States water pollution law, requiring permits for discharges into navigable waters and setting water quality standards.
Definition
The Clean Water Act is the primary US federal law governing water pollution, enacted in 1972. It makes discharging pollutants from a point source into US waters unlawful without a permit, establishes the National Pollutant Discharge Elimination System, sets technology-based effluent standards and water quality criteria, and funds municipal wastewater treatment.
Quick reference
At a glance
- Subject
- Governance & Policy
- Editorial status
- Editorial draft
- Definition status
- Established
- Last updated
- 19 August 2026
- Also known as
- CWA · Clean Water Act of 1972
Overview
What it means
Industrial and municipal dischargers operate under permits that translate ambient water quality goals into enforceable numeric limits.
How it is used
Facilities hold NPDES permits; regulators and courts wrestle with the definition of "waters of the United States"; wetlands development requires dredge-and-fill permits.
Why it matters
It transformed US water quality and remains the central battleground over federal jurisdiction and pollution accountability.
Review
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