Maritime discharge of sewage can harm the environment and people by contaminating seafood, transmitting diseases to water users and, in creating conditions unsuitable for marine life. While the effects of sewage discharge from one boat may be minor, the cumulative effects of the whole maritime sector are significant.
The Resource Management (Marine Pollution) Regulations 1998 (the Regulations) outline treatment standards that specify where sewage can be discharged in order to control pollution of the sea from sewage.
In general, untreated sewage may not be discharged within 500 metres from land, or in water less than 5 metres deep.There are fewer restrictions on the discharge of treated sewage.
To further protect the public and the marine environment, the Regulations prohibit sewage discharge near marine farms, mataitai (traditional food collection) reserves or marine reserves.
Where regional councils determine more protection is needed, they may increase the area where Grade B and untreated sewage discharges are prohibited. Boat operators should become familiar with local rules in regional coastal plans.
Resource Management (Marine Pollution) Regulations 1998 [New Zealand Parliamentary Counsel Office]
Note: Fiordland is specifically recognised in the Regulations because discharge restrictions apply to sewage, both treated and untreated.
Regional Coastal Plan for Southland - September 2008 [Environment Southland]
If heading to the Southern Ocean, operators should note that Marine Protection Rule Part 160 restricts the discharge of sewage in the Antarctic Treaty Area below 60˚S.