Stop the discharge of washwater from scrubbers

Ships should switch to cleaner fuels rather than using scrubbers to reduce their SO₂ emissions, says the international research organisation International Council for the Exploration of the Sea (ICES), which consists of more than 4,000 researchers from 20 countries.

Until such a fuel shift is completed, the discharging of scrubber water into the marine environment should be avoided. According to ICES, this will require significant investment in technological advances and port reception facilities to enable the use of closed-loop scrubber systems with land-based disposal and treatment.

Until scrubber water discharge can be avoided, ICES recommends that: A) Discharges in specific areas (e.g. Particularly Sensitive Sea Areas and Special Areas, as defined by the IMO) should be banned; B) Stringent limits for contaminants in discharge water should be set and enforced; and C) Further development of standards and protocols for measuring, monitoring, and reporting on scrubber discharge water for contaminants and other parameters should be ensured

Source: ICES Viewpoint, 24 September 2020. Link:

In this issue


The clock is ticking to achieve the 1.5°C goal of the Paris Agreement. To be clear right from the start: this goal deserves every effort that mankind can pull off. In the name of realism, this is the goal we must focus on now, given the current level of progress in reducing greenhouse gases. However, damage to marine ecosystems will not be avoided even if we reach this goal1. In fact, damage already occurs at current levels of warming, as evidenced by the bleaching of coral reefs2. This may be an inconvenient truth when our current goal is 1.5°C.

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