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NPDES Regulations
Regulations of Other NPDES Program Areas * Animal feeding operations * National pretreatment program * Pesticide applications * Stormwater * Vessels incidental discharge permitting
EPA originally published the general NPDES regulations at Title 40 of the Code of Federal Regulations (CFR) in 1972. The primary regulations developed by EPA to implement and administer the NPDES permit program are: * Part 122: EPA-Administered Permit Programs: The National Pollutant Discharge Elimination SystemExit EPA’s website * Part 123: State Program RequirementsExit EPA’s website * Part 124: Procedures for DecisionmakingExit EPA’s website * Part 125: Criteria and Standards for the National Pollutant Discharge Elimination SystemExit EPA’s website
Other important regulations applicable to the NPDES program are: * Part 127: NPDES Electronic ReportingExit EPA’s website * Part 133: Secondary Treatment RegulationExit EPA’s website * Part 403: General Pretreatment Regulations for Existing and New Sources of PollutionExit EPA’s website * Part 501: State Sludge Management Program RegulationsExit EPA’s website * Part 503: Standards for the Use or Disposal of Sewage SludgeExit EPA’s website
2019
Notice and Request for Comment: Trading Baselines
On September 5, 2019, EPA invited the public to consider and comment on policy options that may help promote market-based approaches to water quality improvements. * Federal Register Notice, September 19, 2019 (PDF)Exit EPA’s website(5 pp, 132 K, About PDF)
2018
Final Rule: National Pollutant Discharge Elimination System (NPDES): Applications and Program Updates (Phase 1)
This final rule addresses a subset of the revisions proposed in 2016, modernizes the NPDES regulations, and promotes submission of complete permit applications. * Federal Register Notice, February 12, 2019 (PDF)Exit EPA’s website(15 pp, 326 K, About PDF)
Final Rule: Public Notification for CSOs to the Great Lakes
The January 8, 2018, rule implements Section 425 of the Consolidated Appropriations Act of 2016, which requires EPA to work with the Great Lakes States to establish public notification requirements for combined sewer discharges (CSOs) to the Great Lakes. The requirements address signage, initial notification of local public health departments and other potentially affected entities, initial notification of the public, annual notice provisions, and development of a public notification plan. * Federal Register Notice, January 8, 2018 (PDF)Exit EPA’s website(21 pp, 1.1 MB, About PDF)
2015
Final Rule: NPDES Electronic Reporting
This final rule substitutes electronic reporting for paper-based reports. It requires permittees and regulators to use existing, available information technology to electronically report information and data related to the NPDES permit program in lieu of filing paper-based reports. * Federal Register Notice, October 22, 2015 (PDF)Exit EPA’s website(96 pp, 1 MB, About PDF)
2014
National Pollutant Discharge Elimination System (NPDES): Use of Sufficiently Sensitive Test Methods for Permit Applications and Reporting
EPA finalized minor amendments to the NPDES regulations to require that its Clean Water Act (CWA) regulations to codify that under the NPDES program, only "sufficiently sensitive" analytical test methods may can be used when completing an NPDES permit application and when performing sampling and analysis pursuant to monitoring requirements in an NPDES permit. * Federal Register Notice, September 18, 2014 (PDF)Exit EPA’s website(13 pp, 282 KB, About PDF) * Fact Sheet
Final Rule: Cooling Water Intakes – Existing Electric Generating Plants and Factories
This August 15, 2014, final rule covers roughly 1,065 existing facilities that are designed to withdraw at least 2 million gallons per day of cooling water. The facilities are required to choose one of seven options to reduce mortality to fish and other aquatic organisms. Facilities that withdraw at least 125 million gallons per day must conduct studies to help their permitting authority determine whether and what site-specific controls, if any, would be required to further reduce mortality of aquatic organisms. New units added to an existing facility are required to reduce mortality of aquatic organisms that achieves one of two alternatives under national entrainment standards. * Federal Register Notice, August 15, 2014 (PDF)Exit EPA’s website(141 pp, 1 MB, About PDF)
National Pollutant Discharge Elimination System (NPDES)
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