33 CFR 151.2025: Ballast water management methods for vessels

Last reviewed: October 14, 2026

This section requires vessels with ballast tanks that operate in the waters of the United States to use one of five ballast water management methods. The methods include a Coast Guard-approved BWMS, PWS water, exchange or an alternate management system, no discharge, or discharge for treatment onshore or to another vessel. It also covers BWMS approval requests and how other laws interact with this subpart.

Applies toThe master, owner, operator, agent, or person in charge of a vessel equipped with ballast tanks that operates in the waters of the United States.

What it says

  1. The master, owner, operator, agent, or person in charge of a vessel with ballast tanks that operates in the waters of the United States must employ one of the listed ballast water management methods.

    33 CFR 151.2025(a)“must employ one of the following ballast water management methods:”
  2. A vessel using a BWMS must install and operate one that the Coast Guard has approved under 46 CFR part 162, and must install it in accordance with § 151.2035(b) of this subpart.

    33 CFR 151.2025(a)(1)“Install and operate a ballast water management system (BWMS) that has been approved by the Coast Guard under 46 CFR part 162.”
  3. Unless this subpart expressly provides otherwise, vessels with a Coast Guard-approved BWMS must meet the applicable ballast water discharge standard in § 151.2030 of this subpart at all times of discharge into the waters of the United States.

    33 CFR 151.2025(a)(1)“must meet the applicable ballast water discharge standard (BWDS), found in § 151.2030 of this subpart, at all times of discharge into the waters of the United States.”
  4. Vessels using water from a U.S. public water system as ballast must keep a record of which PWS supplied the water, plus a receipt, invoice, or other documentation from the PWS showing the water came from that system.

    33 CFR 151.2025(a)(2)“Vessels using water from a PWS as ballast must maintain a record of which PWS they received the water from”
  5. A vessel that uses ballast water exchange must perform complete exchange in an area 200 nautical miles from any shore before discharging ballast water, unless the vessel must employ an approved BWMS under the schedule in § 151.2035(b) of this subpart.

    33 CFR 151.2025(a)(3)“Perform complete ballast water exchange in an area 200 nautical miles from any shore prior to discharging ballast water,”
  6. A vessel using an alternate management system may employ it for no longer than 5 years from the date the vessel would otherwise have to comply with the BWDS under § 151.2035(b) of this subpart.

    33 CFR 151.2025(a)(3)“may employ the AMS for no longer than 5 years from the date they would otherwise be required to comply with the BWDS”
  7. A vessel owner or operator discharging ballast water to an onshore facility or another vessel for treatment must ensure that vessel piping and supporting infrastructure up to the last manifold or valve prevents untreated ballast water from being discharged into waters of the United States.

    33 CFR 151.2025(a)(5)“prevents untreated ballast water from being discharged into waters of the United States.”
  8. A vessel engaged in the foreign export of Alaskan North Slope Crude Oil must comply with §§ 151.2060 and 151.2070 of this subpart and with 15 CFR 754.2(j)(1)(iii).

    33 CFR 151.2025(c)“A vessel engaged in the foreign export of Alaskan North Slope Crude Oil must comply with §§ 151.2060 and 151.2070 of this subpart”

Common questions

What are the ballast water management options for vessels in U.S. waters?

A vessel with ballast tanks must use one of the methods listed in paragraph (a). These are an approved BWMS, PWS water, exchange or an alternate management system, no discharge, or discharge for treatment onshore or to another vessel.

“must employ one of the following ballast water management methods:”

Where do I send a request for approval of a BWMS?

Requests must go to the Commanding Officer (MSC), Marine Safety Center, at the address given, or by email to msc@uscg.mil, in accordance with 46 CFR part 162.

“or by email to msc@uscg.mil, in accordance with 46 CFR part 162.”

Does this subpart authorize discharges of oil or noxious liquid substances?

No. This subpart does not authorize the discharge of oil or NLS in a manner prohibited by United States or international laws or regulations.

“This subpart does not authorize the discharge of oil or noxious liquid substances (NLS) in a manner prohibited by United States or international laws or regulations.”

Are vessels with a BWMS installed for independent laboratory testing compliant?

Yes. Vessels with a BWMS installed for testing and evaluation by an Independent Laboratory under the cited 46 CFR sections are deemed to comply with paragraph (a)(1).

“will be deemed to be in compliance with paragraph (a)(1) of this section.”

The text of 33 CFR 151.2025

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Ballast water management requirements

(a) The master, owner, operator, agent, or person in charge of a vessel equipped with ballast tanks that operates in the waters of the United States must employ one of the following ballast water management methods:

(1) Install and operate a ballast water management system (BWMS) that has been approved by the Coast Guard under 46 CFR part 162. The BWMS must be installed in accordance with § 151.2035(b) of this subpart. Following installation, the master, owner, operator, agent, or person in charge of the vessel subject to this subpart must properly maintain the BWMS in accordance with all manufacturer specifications. 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 (BWDS), found in § 151.2030 of this subpart, at all times of discharge into the waters of the United States.

(2) Use only water from a U.S. public water system (PWS), as defined in 40 CFR 141.2, 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 from as well as 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)(2)(i) or (ii) of this section, as applicable, and describe in the BWM plan the procedures to be used to ensure compliance with those conditions, and thereafter document such compliance in the BW record book. Vessels using water from a PWS must use such water exclusively unless the usage is in accordance with § 151.2040 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.

(3) Perform complete ballast water exchange in an area 200 nautical miles from any shore prior to discharging ballast water, unless the vessel is required to employ an approved BWMS per the schedule found in § 151.2035(b) of this subpart. An alternate management system (AMS) that meets the requirements of § 151.2026 of this subpart 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 BWDS in accordance with § 151.2035(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 BWDS in accordance with § 151.2035(b) of this subpart;

(4) Do not discharge ballast water into waters of the United States.

(5) Discharge to a facility onshore or to another vessel for purposes of treatment. Any vessel owner/operator discharging ballast water to a facility onshore or to another vessel must ensure that all vessel piping and supporting infrastructure up to the last manifold or valve immediately before the dock manifold connection of the receiving facility or similar appurtenance on a reception vessel prevents untreated ballast water from being discharged into waters of the United States.

(b) 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, in accordance with 46 CFR part 162.

(c) A vessel engaged in the foreign export of Alaskan North Slope Crude Oil must comply with §§ 151.2060 and 151.2070 of this subpart, as well as with the provisions of 15 CFR 754.2(j)(1)(iii). Section 15 CFR 754.2(j)(1)(iii) requires a mandatory program of deep water ballast exchange unless doing so would endanger the safety of the vessel or crew.

(d) This subpart does not authorize the discharge of oil or noxious liquid substances (NLS) in a manner prohibited by United States or international laws or regulations. Ballast water carried in any tank containing a residue of oil, NLS, or any other pollutant must be discharged in accordance with applicable laws and regulations.

(e) This subpart does not affect or supersede any requirement or prohibition 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 to 1376).

(f) This subpart does not affect or supersede any requirement or prohibition pertaining to the discharge of ballast water into the waters of the United States under the National Marine Sanctuaries Act (16 U.S.C. 1431 et seq.).

(g) Vessels with installed BWMS for testing and evaluation by an Independent Laboratory in accordance with the requirements of 46 CFR 162.060-10 and 46 CFR 162.060-28 will be deemed to be in compliance with paragraph (a)(1) of this section.

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.