The purpose of the law is to prevent the discharge of sewage, and contribute to less sewage discharge along the Norwegian coast, especially in inland waters with less electricity and less water exchange.
Commenting on the new rules, Bjørn E. Pedersen, Department Director of the Norwegian Maritime Directorate, said that:
The potential for sewage discharges is great, and the proposal will entail a monthly reduction of sewage emissions and help to protect the environment and health
In Norwegian waters, emission requirements are less strict than those set out in the international regulations in MARPOL Annex IV. These rules establish that the limit for sewage emissions is at 12 nautical miles, namely 22,224 meters from land. Furthermore, MARPOL Annex IV requires that all vessels covered by the regulations must be equipped with sewage treatment plants, grinding, disinfecting plants, and or collection tanks. For painted and disinfected sewers, the boundary is at three nautical miles.
In Norway, impure sewage can be discharged 300 meters from land along large parts of the coast. This is because of the fact that many municipalities lack of sewage treatment plants when the regulations were introduced, in addition to generally good circulation in the water bodies along the coast.
In Norway, the rules in MARPOL Appendix IV apply only to ships in foreign trade on the lines from Lindesnes to the Swedish border. The new rules now propose to make emission requirements in MARPOL Annex IV applicable both to ships in international and domestic shipping, throughout the Norwegian waters.
The proposal aims at vessels with international certificates, irrespective of year of construction and for passenger ships with "small coastal speed" or less, or "coastal fishing or less" with gross tonnage 400 or more, and which is certified for more than 100 passengers.
This also applies to newbuildings of more than 400 gross tonnes, which have a contract date after March 1, 2020, and which are certified for more than 15 people and will operate in the "small coastal" or "coastal fishing" shipping area.
If these vessels are operating at speeds that make it difficult to maintain the geographical boundary, they then must have sewage treatment plants or paint and disinfectants. Alternatively, they may have sewage collection tanks on board, which can be delivered to land for emptying.
For passenger ships in scheduled shipping in Norway, a phasing in of emission requirements for sewage has been suggested.
Ships that are not covered by the new boundary must continue to follow the current emission limit, which applies for 300 meters from mainland and islands.