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National Pollutant Discharge Elimination System (NPDES)

Vessels-Program History

EPA created the NPDES vessels incidental discharge permitting program in response to a court decision vacating EPA’s longstanding permit exclusion of discharges incidental to the normal operation of a vessel.  Additional information on that court decision, legislation, and EPA activities to develop and implement the program are provided below.

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Vessels Incidental Discharge Litigation

The NPDES permitting of incidental discharges from vessels came about as a result of litigation:

  • March 30, 2005 - The U.S. District Court for the Northern District of California (in Northwest Environmental Advocates et al. v. EPA) rules that the EPA regulation, [40 CFR (Code of Federal Regulations, Title 40) Part 122.3(a) (PDF)(1 pp, 146 KB, About PDF) - exclusions excluding discharges incidental to the normal operation of a vessel from NPDES permitting], exceeds the Agency's authority under the CWA.
  • September 18, 2006 - The Court issues an order revoking the regulatory provision excluding incidental discharges from permitting as of September 30, 2008. EPA appeals this decision.
  • July 23, 2008 - the Ninth Circuit upholds the court order, leaving the September 30, 2008 vacatur date in effect (which the district court subsequently extended to December 19, 2008). 

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Vessels Incidental Discharge Legislation

Several subsequently enacted laws affected the applicability of that court decision:

  • Public law (P.L.) 110-288 (PDF) (4 pp, 134 KB, About PDF- signed into law on July 29, 2008, provides that recreational vessels shall not be required to obtain an NPDES permit for discharges incidental to their normal operation. It instead directs EPA to evaluate recreational vessel discharges, develop management practices for appropriate discharges, and promulgate performance standards for those management practices. It then directs the U.S. Coast Guard (USCG) to promulgate regulations for the use of the management practices developed by EPA and requires recreational boater compliance with such practices. (Senate bill S. 2766 - "the Clean Boating Act of 2008").
  • P.L. 110-299 (PDF)(3 pp, 132 KB, About PDF) - signed into law on July 31, 2008, and generally imposes a moratorium during which time neither EPA nor states may require NPDES permits for discharges incidental to the normal operation of commercial fishing vessels and other non-recreational vessels less than 79 feet, other than for ballast water, until July 31, 2010. In addition, P.L. 110-299 directs EPA to conduct a study of vessel discharges and issue a report to Congress. EPA finalized this Report to Congress in August 2010. (Senate bill S. 3298).
  • Several bills after P.L. 110-299 extended the NPDES permitting moratorium:
    • P.L. 111-215 (PDF)(7 pp, 140 KB, About PDF- signed into law on July 30, 2010, extends the moratorium to December 18, 2013. (Senate bill S. 3372).
    • P.L. 112-213 (PDF) (48 pp, 217 KB, About PDF- signed into law on December 20, 2012. Section 703 extends the moratorium to December 18, 2014. (House of Representatives bill H.R. 2838).
    • P.L. 113-281 (PDF)(44 pp, 289 KB, About PDF- signed into law on December 18, 2014. Section 602 extends the moratorium to December 18, 2017. (Senate bill S. 2444 - "the Howard Coble Coast Guard and Maritime Transportation Act of 2014").
    • Senate Bill S. 2273 - signed into law on January 3, 2018, and extends the moratorium to January 19, 2018.

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2010 Vessels Report to Congress

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Studies to Improve Our Understanding of Ballast Water Discharges

The EPA and the USCG jointly commissioned two scientific studies to better inform EPA’s understanding of ballast water discharges. EPA considered the results of these studies in developing the vessels incidental discharge permitting program.

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Environmental Technology Verification (ETV) Protocol for Ballast Water Treatment Technology

  • Generic Protocol for the Verification of Ballast Water Treatment Technology (September 2010)  – EPA developed this protocol in cooperation with the USCG.  It evaluates the performance characteristics of commercial-ready ballast water treatment technologies with regard to specific verification factors, including biological treatment performance, predictability/reliability, cost, environmental acceptability, and safety for land-based testing facilities. Ballast water treatment systems that perform well using this protocol will have a reasonable chance of performing well; although, shipboard trials are also necessary to adequately assess shipboard technology performance.

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