As of July 1, 2025, Finland will prohibit cargo ships from discharging toilet wastewater, scrubber sludge, and sulfur cleaning water into the country’s coastal waters. This regulation makes Finland the first nation to enforce such restrictions on cargo vessel wastewater discharges, following parliamentary approval of the law in December 2024.

Passenger ships have been subject to similar restrictions for many years, but this marks the first time cargo ships are also included.

The legislation targets wastewater types that directly contribute to marine pollution. Toilet wastewater, for instance, contains high concentrations of intestinal bacteria, solids, and nutrients that promote eutrophication — a process that depletes oxygen in marine environments and triggers harmful algal blooms.

Although the discharges are now banned, a transition period has been granted. Greywater from showers and sinks may still be discharged into Finnish waters for the next five years.

All types of wastewater remain legally dischargeable beyond Finland’s territorial waters.

According to environmental authorities, the new regulation represents a significant step in protecting the Baltic Sea, which has long suffered from nutrient pollution. Eutrophication remains one of the region’s most severe ecological threats.