What is the BWM Convention? — Ballast Water Management Convention 2004

Definition: What is the BWM Convention?

The International Convention for the Control and Management of Ships’ Ballast Water and Sediments (BWM Convention) was adopted by IMO in 2004 and entered into force on 8 September 2017. It establishes global standards for ballast water management, aimed at preventing the transfer of harmful aquatic organisms and pathogens across marine ecosystems.

The two performance standards: D-1 and D-2

• Regulation D-1 — Ballast Water Exchange: ships must exchange at least 95% of their ballast water at least 200 nautical miles from the nearest land and in water at least 200 m deep.
• Regulation D-2 — Ballast Water Performance Standard: ships must treat ballast water to reduce viable organisms below specified thresholds (e.g. fewer than 10 viable organisms per m³ in the ≥50 µm category).

The BWMS Code (MEPC.300(72))

The Code for Approval of Ballast Water Management Systems (BWMS Code) entered into force on 13 October 2019 and sets the testing, type-approval and operational requirements for ballast water management systems. Systems approved under the older G8 Guidelines remain valid until first renewal survey after 28 October 2020, then must meet the BWMS Code.

The experience-building phase (EBP)

The experience-building phase runs in parallel with the D-2 compliance schedule and is designed to capture real-world implementation data, identify challenges and inform future amendments to the BWM Convention. MEPC 84 is expected to consolidate EBP lessons and discuss possible convention amendments.

Documentation on board

Every BWM-compliant ship must carry:

1. International Ballast Water Management Certificate (BWM Certificate) — valid up to 5 years.
2. Ballast Water Management Plan — ship-specific, approved by the flag state.
3. Ballast Water Record Book (BWRB) — records every ballast operation.

Port State Control and BWM

PSC inspections increasingly include ballast water sampling. Under the Paris MoU and Tokyo MoU, non-compliance with D-2 is a detainable deficiency, as is absence of the BWM Certificate or a valid BWMP.

Interaction with IHM and ESG reporting

Ballast water treatment chemicals and components are tracked in IHM Part I under Table B (operationally generated substances) where present. From an ESG perspective, BWM is a biodiversity disclosure under ESRS E4.