Starting today, it will be illegal for cargo ships to discharge toilet wastewater, sulphuric wash water, and scrubber sludge into Finnish coastal waters, marking a global first in maritime environmental regulation.
The new rules, approved by Finland’s parliament in December 2024, put the Nordic nation at the forefront of marine pollution control, building on earlier bans already in place for passenger ships. The move makes Finland the first country in the world to implement such a comprehensive wastewater discharge ban for commercial cargo vessels operating near its coastline.
Toilet wastewater discharged by ships is rich in intestinal bacteria, suspended solids, and nutrients — a potent cocktail that contributes directly to eutrophication. This process, caused by excess nutrients in the water, triggers harmful algae blooms, particularly blue-green algae, which deplete oxygen levels and devastate marine ecosystems.
Marine scientists and environmental groups have welcomed the new rules as a major step toward protecting the fragile Baltic Sea, long identified as one of the most polluted enclosed seas in the world.
While the ban targets some of the most harmful waste streams, the legislation allows extended grace periods for other types of wastewater. Greywater — including water from sinks, showers, and galley drains — will still be permitted in Finnish waters for nearly five more years.
Furthermore, all forms of ship wastewater discharge will remain legal beyond Finland’s territorial waters, meaning stricter enforcement will apply only within its exclusive maritime zone.
The ban also extends to scrubber sludge and sulphuric wash water, waste products linked to ships that use exhaust gas cleaning systems – also known as scrubbers – to meet sulphur emission rules. These byproducts have come under increasing scrutiny for being dumped into the sea, effectively shifting pollution from the air to the ocean.
Shipping companies operating in the Baltic region will need to upgrade holding tank capacity or arrange for port reception facilities to offload waste safely.