33 CFR 151.1510: Ballast water management practices for vessels
Last reviewed: October 14, 2026
This section requires the master of each vessel subject to this subpart to employ one of four ballast water management practices: mid-ocean exchange, retention on board, an approved BWMS, or use of public water system water. It also limits sediment discharge and says the subpart does not authorize prohibited discharges of oil or noxious liquid substances.
Applies toThe master of each vessel subject to this subpart.
What it says
The master of each vessel subject to this subpart must employ one of the listed ballast water management practices.
33 CFR 151.1510(a)“The master of each vessel subject to this subpart shall employ one of the following ballast water management practices:”
One practice is a ballast water exchange beyond the EEZ, more than 200 nautical miles from any shore, in waters more than 2,000 meters deep, so that tanks to be discharged hold water of at least 30 parts per thousand salinity, unless the vessel must use an approved BWMS under the schedule in § 151.1512(b).
33 CFR 151.1510(a)(1)“contains water with a minimum salinity level of 30 parts per thousand, unless the vessel is required to employ an approved ballast water management system (BWMS) per the schedule in § 151.1512(b) of this subpart.”
A vessel may instead retain its ballast water on board, and if it does, the COTP may seal any tank or hold containing ballast water for the voyage within the waters of the Great Lakes or the Hudson River, north of the George Washington Bridge.
33 CFR 151.1510(a)(2)“the COTP may seal any tank or hold containing ballast water on board the vessel for the duration of the voyage”
A vessel may install and operate a BWMS approved by the Coast Guard under 46 CFR part 162, and the responsible persons must maintain it in accordance with all manufacturer specifications.
33 CFR 151.1510(a)(3)“must maintain the BWMS in accordance with all manufacturer specifications.”
A vessel using water from a U.S. public water system as ballast must keep a record of which system supplied the water and a receipt, invoice, or other documentation from that system.
33 CFR 151.1510(a)(4)“must maintain a record of which PWS they received the water and a receipt, invoice, or other documentation from the PWS indicating that water came from that system.”
The master must not separately discharge sediment from tanks or holds containing ballast water unless it is disposed of ashore in accordance with local requirements.
33 CFR 151.1510(b)“No master of a vessel subject to this subpart shall separately discharge sediment from tanks or holds containing ballast water unless it is disposed of ashore in accordance with local requirements.”
Vessels using a Coast Guard-approved BWMS must meet the applicable ballast water discharge standard in § 151.1511 at all times of ballast water discharge into the waters of the United States, unless this subpart expressly provides otherwise.
33 CFR 151.1510(d)“must meet the applicable ballast water discharge standard, found in § 151.1511 of this subpart, at all times of ballast water discharge into the waters of the United States.”
Common questions
Where must a ballast water exchange take place?
The exchange must be beyond the EEZ, more than 200 nautical miles from any shore, in waters more than 2,000 meters deep. It must occur before entering the Snell Lock at Massena, NY, or navigating on the Hudson River north of the George Washington Bridge.
“This exchange must occur prior to entry into the Snell Lock at Massena, NY, or navigating on the Hudson River, north of the George Washington Bridge.”
How long may an alternative management system be used?
The responsible persons may employ the AMS for no longer than 5 years from the date they would otherwise be required to comply with the ballast water discharge standard under § 151.1512(b).
“may employ the AMS for no longer than 5 years from the date they would otherwise be required to comply with the ballast water discharge standard”
What must a vessel using public water system water as ballast have done to its tanks?
The vessel must have either previously cleaned the ballast tanks, including removing all residual sediments, and not subsequently introduced ambient water, or never introduced ambient water to those tanks and supply lines.
“Previously cleaned the ballast tanks (including removing all residual sediments) and not subsequently introduced ambient water; or”
Does this subpart allow discharge of oil or noxious liquid substances?
No. Nothing in this subpart authorizes the discharge of oil or NLSs in a manner prohibited by United States or international laws or regulations.
“Nothing in this subpart authorizes the discharge of oil or noxious liquid substances (NLSs) in a manner prohibited by United States or international laws or regulations.”
The text of 33 CFR 151.1510
Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR
Ballast water management requirements
(a) The master of each vessel subject to this subpart shall employ one of the following ballast water management practices:
(1) Carry out an exchange of ballast water on the waters beyond the Exclusive Economic Zone (EEZ), from an area more than 200 nautical miles from any shore, and in waters more than 2,000 meters (6,560 feet, 1,093 fathoms) deep, such that, at the conclusion of the exchange, any tank from which ballast water will be discharged contains water with a minimum salinity level of 30 parts per thousand, unless the vessel is required to employ an approved ballast water management system (BWMS) per the schedule in § 151.1512(b) of this subpart. This exchange must occur prior to entry into the Snell Lock at Massena, NY, or navigating on the Hudson River, north of the George Washington Bridge. An alternative management system (AMS) that meets the requirements of 33 CFR 151.2026 may also be used, so long as it was installed on the vessel prior to the date that the vessel is required to comply with the ballast water discharge standard in accordance with § 151.1512(b) of this subpart. If using an AMS, the master, owner, operator, agent, or person in charge of the vessel subject to this subpart may employ the AMS for no longer than 5 years from the date they would otherwise be required to comply with the ballast water discharge standard in accordance with § 151.1512(b) of this subpart.
(2) Retain the vessel's ballast water on board the vessel. If this method of ballast water management is employed, the COTP may seal any tank or hold containing ballast water on board the vessel for the duration of the voyage within the waters of the Great Lakes or the Hudson River, north of the George Washington Bridge.
(3) Install and operate a BWMS that has been approved by the Coast Guard under 46 CFR part 162, in accordance with § 151.1512(b) of this subpart. Following installation of a BWMS, the master, owner, operator, agent, or person in charge of the vessel must maintain the BWMS in accordance with all manufacturer specifications.
(i) Requirements for approval of BWMS are found in 46 CFR part 162.060.
(ii) Requests for approval of BWMS must be submitted to the Commanding Officer (MSC), Attn: Marine Safety Center, U.S. Coast Guard Stop 7430, 2703 Martin Luther King Jr. Avenue SE., Washington, DC 20593-7430, or by email to msc@uscg.mil.
(4) Use only water from a U.S. public water system (PWS), as defined in 40 CFR 141.2 and that meets the requirements of 40 CFR parts 141 and 143, as ballast water. Vessels using water from a PWS as ballast must maintain a record of which PWS they received the water and a receipt, invoice, or other documentation from the PWS indicating that water came from that system. Furthermore, they must certify that they have met the conditions in paragraphs (a)(4)(i) or (ii) of this section, as applicable. Vessels using water from a PWS must use such water exclusively for all ballast water unless the usage is in accordance with § 151.1515 of this subpart. Vessels using PWS water as ballast must have either—
(i) Previously cleaned the ballast tanks (including removing all residual sediments) and not subsequently introduced ambient water; or
(ii) Never introduced ambient water to those tanks and supply lines.
(b) No master of a vessel subject to this subpart shall separately discharge sediment from tanks or holds containing ballast water unless it is disposed of ashore in accordance with local requirements.
(c) Nothing in this subpart authorizes the discharge of oil or noxious liquid substances (NLSs) in a manner prohibited by United States or international laws or regulations. Ballast water carried in any tank containing a residue of oil, NLSs, or any other pollutant must be discharged in accordance with the applicable regulations. Nothing in this subpart affects or supersedes any requirement or prohibitions pertaining to the discharge of ballast water into the waters of the United States under the Federal Water Pollution Control Act (33 U.S.C. 1251 et seq.).
(d) Unless otherwise expressly provided for in this subpart, the master, owner, operator, agent, or person in charge of vessels employing a Coast Guard-approved BWMS must meet the applicable ballast water discharge standard, found in § 151.1511 of this subpart, at all times of ballast water discharge into the waters of the United States.
Sections it refers to
The plain-English explanation on this page was written with AI from the regulation text above and checked automatically before publishing: every quote appears in the text, every number comes from it, and a second model confirmed each statement adds nothing the text doesn't say. Regulation text current as of April 16, 2026. The regulation text governs. RegKnot is not affiliated with the U.S. Coast Guard.