FINLAND has become the first nation to ban wastewater discharge from vessels in its exclusive economic zone, after legislation passed in December 2024 entered into force on July 1, 2025.

All vessels flying the Finnish flag as well as vessels of more than 400 gt will be prohibited from discharging sewage and sewage effluent (or “blackwater”) in Finnish waters from today.

Ships will also be banned from emptying open-loop scrubber water in Finnish waters too, the amount of pollution in which has been debated by various studies.

Washwater from closed-loop systems will still be able to discharged until January 1, 2029.

A ban on shower and sink water (or “greywater”) will enter into force on January 1, 2030.

Finland-flagged icebreakers are excluded from the new regulation.

Baltic Sea Action Group chief executive Ville Wahlberg said it was “highly welcome that Finland is addressing harmful ship emissions into the Baltic Sea through legislation”.

“The bill is thorough and comprehensive, but as members of parliament Tiina Elo (Green League) and Timo Furuholm (Left Alliance) pointed out during committee reviews, the proposed transitional provisions should be more ambitious.”

BSAG maritime project co-ordinator Laura Rantanen said Finnish ports already had “excellent capabilities for receiving ship-based blackwaters”.

A waste fee is charged whether a ship discharges waste at a Finnish port or not, removing any cost-saving incentive to discharge at sea.

But the new legislation meant port wastewater discharge may increase sharply, and ports should be planning for a surge, Rantanen said.

Wahlberg said the shift should be to international co-operation and advocacy, to ensure no wastewater is discharged in the Baltic Sea at all.