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Wednesday, February 10, 2021  (Comments: 1)

Together with a number of member states and international organisations, BIMCO has proposed that the IMO should reconsider the direction in which the amendment of MARPOL Annex IV has taken concerning existing ships.

BIMCO has participated in an intersessional correspondence group which has been working on preparing draft amendments to MARPOL Annex IV on sewage. The report has been submitted to the eighth session of IMO’s subcommittee on Pollution Prevention and Response (PPR 8) for debate.

The draft amendments outline a set of new requirements pertaining to onboard tests verifying the performance of the installed sewage treatment plants (STP), and relevant requirements of a survey regime. Furthermore, the report proposes new equipment requirements and a discharge of sewage management system.

One of the proposed measures introduces stricter standards for effluent from sewage treatment plants (STPs) and new parameters with regard to the measurement of turbidity and total residual oxidizers. The STPs on existing ships are not designed to meet these proposed new parameters.

Instead of the above mentioned stricter requirements, BIMCO and the co-sponsors of this submission have made an alternative suggestion, which is based on developing concrete measures to improve the effluent quality from STPs already installed on existing ships as well as monitor the level of improvement of effluent quality from sewage treatment plants.

Reader Comments (1)

An interetsing development but any changes to MARPOL Annex IV should also include grey water, which continues to be, well, a grey area. When discharged into the marine environment, the oils, fats, detergents, soap, shower gel, chemicals, greases, galley waste, micro- and nanoplastic, etc etc etc, that make up the grey water stream can flood the surrounding environment with nutrients and is more damging to the envirinment than black water. Any changes to sewage rules should also take in to account nano plastics. Researchers at the Medical University of Vienna and the Environment Agency Austria analysed stool samples from eight participants around the world. The samples contained up to nine different plastics of between 50 and 500 micrometres in size. On average, researchers found 20 microplastic particles per 10g of stool.

By Patrik Wheater on Wednesday, February 10, 2021

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