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Please note: This summary is provided to help you understand the regulations. Consult the references provided for links to the full text of the regulations.

BilgewaterBilgewater

Road Rail Air Water

Bilgewater, the water that collects in the lowest part of a vessel, generally picks up numerous contaminants such as lubricating oils and cleaning wastes. Regulations on bilgewater discharges have been developed to ensure that the contaminants do not become environmental problems. On most vessels, bilgewater can be managed in one of two ways; it can be:

  • Retained onboard in a holding tank and discharged later to a reception facility on shore, or
  • Treated onboard with an oily water separator (OWS) after which the treated bilgewater can be discharged overboard in accordance with applicable standards and regulations.

Regulations impacting bilgewater discharges in U.S. Waters are implemented by the U.S. Environmental Protection Agency (EPA) and the U.S. Coast Guard. EPA's National Pollutant Discharge Elimination System (NPDES) vessels program regulates bilgewater and other incidental discharges from the normal operation of vessels. U.S. Coast Guard bilgewater regulations are based on the MARPOL Annex I, Regulations for the Prevention of Pollution by Oil ("MARPOL" is short for marine pollution), which addresses oil pollution and lists oil prevention requirements for machinery spaces on all ships covered by the Convention and provides requirements for cargo areas of oil tankers.



Who is covered by the regulations?

U.S. EPA

Bilgewater discharge regulations apply to any vessel that requires a Vessel General Permit (VGP). This includes any vessel of 79 feet or greater in length, except for military and recreational vessels.

Overall, the VGP program applies to more than 61,000 commercial vessels in the U.S. and to more than 8,000 foreign vessels operating in the navigable waters of the United States. Failure to have NPDES permit coverage may result in severe civil and criminal penalties.

U.S. Coast Guard

The U.S. Coast Guard regulations apply to all U.S. Flagged ships anywhere in the world and to all foreign flagged vessels operating in the navigable waters of the U.S., or while at a port under U.S. Jurisdiction.

States and Territories

Vessels operating in certain areas may be required to follow additional state and territorial requirements. These additional requirements are listed in section 6 of the 2013 VGP.

What is the purpose of the regulations?

Many of the contaminants found in bilgewater are toxic to humans and animals. Oils present some of the worst problems. Light oils form a film on the surface of water. Until the film evaporates, its toxic constituents remain concentrated on the surface, posing a risk to any humans, waterfowl, or other animals that may come in contact with it. Medium and heavy weight oils tend not to evaporate, and can collect on the seabed, damaging organisms, contaminating shellfish beds, and creating nuisances such as tar balls on beaches.

Regulations

U.S Environmental Protection Agency

EPA's NPDES vessels program regulates incidental discharges from the normal operation of vessels using the Vessel General Permit or VGP. These discharges include, but are not limited to, bilgewater, ballast water, graywater (e.g., water from sinks, showers), and deck runoff/washdown.

The VGP requires that vessel owners and operators meet certain requirements, including seeking coverage for most vessels, assuring their discharges meet effluent limits and related requirements, corrective action process for fixing permit violations, and requirements for inspections, monitoring, recordkeeping and reporting.

Bilge discharges are subject to the rules found in section 2.2.2 of the VGP. Readers are urged to download the VGP and read it before taking any action. The following is a summary of the VGP regulations covering the discharge of bilgewater:

  • Vessel operators may not use dispersants, detergents, emulsifiers, chemicals or other substances to remove the appearance of a visible sheen in their bilgewater discharges.
  • Except in the case of flocculants or other required additives (excluding any dispersants or surfactants) used to enhance oil/water separation during processing (after bilgewater has been removed from the bilge), vessel operators may not add substances that drain to the bilgewater that are not produced in the normal operation of a vessel.
  • All vessels must minimize the discharge of bilgewater into waters subject to the VGP. This can be done by minimizing the production of bilgewater, disposing of bilgewater on shore where adequate facilities exist, or discharging into waters not subject to this permit (i.e., more than 3 nautical miles (nm) from shore) for vessels that regularly travel into such waters.
  • Vessels greater than 400 gross tons may not discharge untreated oily bilgewater into waters subject to the VGP.
  • Vessels greater than 400 gross tons that regularly sail outside the territorial sea (at least once per month) may not discharge treated bilgewater within 1 nm of shore if technologically feasible (e.g. holding would not impact safety and stability, would not contaminate other holds or cargo, or would not interfere with essential operations of the vessel).
  • Vessels greater than 400 gross tons may not discharge treated bilgewater into federally protected waters (e.g. marine sanctuaries, national parks) unless the discharge is necessary to maintain the safety and stability of the ship.
  • For vessels greater than 400 gross tons that regularly sail outside the territorial sea (at least once per month), if treated bilgewater is discharged into waters subject to this permit, it must be discharged when vessels are underway (sailing at speeds greater than 6 knots), unless doing so would threaten the safety and stability of the ship.

In addition to the above VGP requirements, several regulations are included in the VGP by reference that relate to bilgewater management. All bilgewater discharges must be in compliance with these regulations:

Though not regulated under the VGP, EPA notes that discharges of bilgewater outside waters subject to this permit (i.e., more than 3 nm from shore) are regulated under Annex I of the International Convention for the Prevention of Pollution from Ships as implemented by the Act to Prevent Pollution from Ships and U.S. Coast Guard regulations found in 33 CFR 151.09.

U.S. Coast Guard

U.S. Coast Guard bilgewater regulations are based on the MARPOL Annex I, Regulations for the Prevention of Pollution by Oil, which addresses oil pollution and lists oil prevention requirements for machinery spaces on all ships covered by the Convention and provides requirements for cargo areas of oil tankers. The Act to Prevent Pollution from Ships is the U.S. Federal law implementing those provisions of MARPOL that have been ratified by the United States.

Coast Guard regulations (33 CFR 151.10) require that, when within 12 nautical miles (nm) of the nearest land, any discharge of oil or oily mixtures into the sea from a ship is prohibited except when all of the following conditions are satisfied:

  • The oil or oily mixture does not originate from cargo pump room bilges.
  • The oil or oily mixture is not mixed with oil cargo residues.
  • The oil content of the effluent without dilution does not exceed 15 parts per million (ppm).
  • The ship has in operation oily-water separating equipment, a bilge monitor, bilge alarm, or combination thereof.
  • The oily-water separating equipment is equipped with a 15 ppm bilge alarm; for U.S. inspected ships, approved under 46 CFR 162.050 (see 33 CFR 151.10 for complete description of equipment requirements).

Coast Guard regulations further require that, when more than 12 nm from the nearest land, any discharge of oil or oily mixtures into the sea from a ship is prohibited except when all of the following conditions are satisfied:

  • The oil or oily mixture does not originate from cargo pump room bilges.
  • The oil or oily mixture is not mixed with oil cargo residues.
  • The ship is not within a special area.
  • The ship is proceeding en route.
  • The oil content of the effluent without dilution is less than 15 ppm.
  • The ship has in operation oily-water separating equipment, a bilge monitor, bilge alarm, or combination thereof.

Additional Coast Guard regulations (33 CFR 151.13) prohibit the discharge of oil or an oily mixture within MARPOL special areas unless the above requirements are met and the vessels oily-water separating equipment is equipped with a device that stops the discharge automatically when the oil content of the effluent exceeds 15 ppm.

Further, Coast Guard regulations (33 CFR 151.10) provide that if the bilge water cannot be discharged in compliance with these standards, then it must be retained onboard or discharged to a designated reception facility. However, both MARPOL and the APPS regulations exempt emergency discharges needed to save the ship or save a life at sea.

Best Practices

Both U.S. EPA and U.S. Coast Guard regulations are founded on best management practices. Please refer to the regulations summarized above.

More Resources

EPA VGP Points of Contact:

U.S. Coast Guard Points of Contact:

Environmental Standards Division (CG-5224)
U.S. Coast Guard Headquarters

2100 Second Street SW
Washington, DC 20593
Tel: 202-372-1402
E-mail: environmental_standards@uscg.mil
Web: www.uscg.mil/environmental_standards/

Additional, related documents:

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