Background
Currently, MARPOL does not explicitly regulate grey water. In connection with passenger/cruise traffic and/or sensitive sea areas, there are some national/regional regulations on grey water whilst others are in the process of being developed.
Grey water is defined by the International Maritime Organization (IMO) as drainage from dishwashers, galley sinks, showers, laundry, baths and washbasin drains. It is a known source of contaminants to the marine environment and has been identified as a vector for microplastics in the oceans.
A limited number of ships have the capacity to collect and hold grey water for discharge and/or subsequent treatment. Most ships discharge grey water directly via runoffs into the sea. Fragmented piping and tank systems on existing ships make it extremely difficult to collect grey water for discharge to reception facilities ashore.
BIMCO’s Position Statement
- BIMCO encourages its members to introduce voluntary operational measures to reduce both the amount of grey water and the sources of contaminants in it, including microplastics.
- BIMCO supports the development of international regulations for new ships on the handling of grey water through the use of collection tank(s) and/or a single pipe for the grey water discharge.
- For existing ships, regulations on minimisation of contaminants and microplastics from grey water should be introduced in a pragmatic and practical way, for example by using treatment devices on washing machines.
- BIMCO recommends that ships should focus on using minimal-toxic and phosphate free products as well as non-harmful biodegradable products where available and on, reducing the use of products containing intentionally-added microplastics wherever possible.
- BIMCO will inform about the available technological solutions and initiate an awareness campaign to nudge possible behavioural change.