Netherlands to enforce scrubber washwater ban in ports from 1 July 2030

The Netherlands will enforce its ban on discharging washwater from open-loop scrubbers in Dutch ports and inland waters from 1 July 2030. Minister of Infrastructure and Water Management Vincent Karremans set the date in a letter to parliament dated 23 September, ahead of a committee debate on maritime affairs on 30 September.

The government decided on a national ban in March 2025 but had not said when it would be enforced. The rules needed to enforce it still have to be written, and the ministry is working out what they and the required enforcement capacity will look like. Karremans described 1 July 2030 as a workable timeframe for both the shipping sector and the enforcing authorities.

The ban applies to open-loop scrubbers, which wash sulphur out of a ship's exhaust with seawater and then discharge that water back into the sea. It lets ships comply with sulphur limits, including the stricter ones in the North Sea emission control area, while continuing to burn heavy fuel oil. Hybrid and closed-loop systems do not always, or never, discharge the washwater. The ministry's decision memo estimates that about 5,000 seagoing ships worldwide carried a scrubber in 2023, around 5% of the global fleet, and cites research estimating that about 490 million tonnes of scrubber washwater were discharged in the North Sea and the Channel in 2022.

The measure follows agreements within OSPAR, under which the participating states will ban open-loop discharges in ports and inland waters. The Netherlands is enforcing there first because the ministry expects the greatest environmental gain. Whether to extend the ban to the 12-nautical-mile zone is being studied, with a final decision due in 2027. A ban beyond that needs international agreement, and the Netherlands is pursuing rules for scrubber washwater at the IMO.

The ministry consulted the Royal Association of Netherlands Shipowners (KVNR), Maritime & Offshore NL, the ports of Rotterdam and Amsterdam, and the North Sea Foundation. Some supported the ban. KVNR and Maritime & Offshore NL raised concerns about the effect on shipowners and on future technology such as onboard carbon capture.

Amsterdam has banned open-loop washwater discharges at its seagoing berths since 1 January 2025. Ships with hybrid systems must switch to closed-loop mode there or burn a compliant fuel such as marine gas oil. About 100 seagoing ships with open-loop scrubbers called at Amsterdam in 2023, and the port pointed to similar bans already in force in Antwerp, Hamburg, French ports and several Scandinavian ports.

This story is part of the Maritime Briefing of 27 September 2026.