Scrubber Washwater Debate Taken to IMO

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Published Feb 17, 2020 5:51 PM by The Maritime Executive

The IMO's Pollution Prevention & Response Subcommittee meets February 17-21 February in London, and debate is expected on the environmental impacts of scrubber washwater.

Among the agenda items during PPR7 is a review of the 2015 Guidelines for Exhaust Gas Cleaning Systems (EGCS) and an evaluation and harmonization of rules and guidance on the discharge of liquid effluents from scrubbers into water.

A paper has been submitted to PPR7 by FOEI, WWF and Pacific Environment titled: “Exhaust gas cleaning system discharges into waters off the west coast of Canada and potential impacts on threatened and endangered marine mammals.” The report highlights potential risks to killer whales from the use of open loop scrubbers, particularly by cruise ships. It states: “Open-loop systems continuously discharge warm, acidic washwater that contains carcinogenic substances such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals. When released into the ocean, these substances pose a threat to aquatic wildlife, including threatened and critically endangered pods of resident killer whales that live off the coast of British Columbia.”

Another paper has also been submitted: “Refining the title and scope of a new output on the discharge of liquid effluents from EGCS.” The paper calls for consideration of the impacts of scrubber effluent on areas of cultural and ecological sensitivity. The paper has been submitted by several international environmental organizations including Friends of the Earth International, World Wildlife Fund, and Pacific Environment. Stand.earth is a supporting organization of the paper.
“This week’s negotiations on the use of scrubbers is timely and urgent, as increasing numbers of ships are installing these systems so they can circumvent the IMO’s 2020 fuel sulfur standards while continuing to burn heavy fuel oil. The cumulative impacts on the marine environment of increasing volumes of scrubber waste being discharged into our seas was not adequately considered prior to allowing their use. The vast majority of these scrubbers are open-loop systems, which effectively turn air pollution into water pollution,” said Kendra Ulrich, Senior Shipping Campaigner at Stand.earth. 
“Installing scrubbers also does nothing to address the spill risk associated with the use of heavy fuel oil and provides inferior reductions to black carbon over simply switching to cleaner fuel sources.”  

Increasing numbers of ports and countries are banning the discharge of scrubber wastewater due to water pollution concerns. A number of regions have already declared that washwater cannot be discharged, including Singapore, Malaysia and the Suez Canal.

However, a number of reports have indicated that it is not a concern. Most recently, the Cruise Lines International Association (CLIA) highlighted the findings of three independent reports released in 2019 that show scrubbers, when operated in open-loop mode, have minimal impact on water and sediment quality.

The most recent report, conducted by CE Delft and co-sponsored by CLIA, analyzed the long-term impact of washwater discharges from scrubbers on port water and sediment. Using empirical data from almost 300 washwater samples—the most extensive dataset of this kind to date—it was found that such discharges have minimal environmental impact on water and sediment quality as compared to new European environmental quality standards entering into force in 2021.

The CE Delft report and its findings follow two additional studies released in 2019 which were conducted to further understand the impact of scrubbers on marine environments. This includes a two-year study conducted by DNV GL, which found washwater samples from 53 cruise ships equipped with scrubbers to be below the limits set by major international water quality standards. Another recent study, conducted by the Japanese Ministry of Land, Infrastructure, Transport and Tourism, found the impact of scrubbers on water quality and marine life to be negligible.
The PPR7 meeting also includes two agenda items that impact the Arctic: a ban on the use of heavy fuel oil in the Arctic and proposals to reduce the impacts of black carbon emissions. 

PPR 7/INF.22 - Exhaust gas cleaning system discharges into water off the west coast of Canada and potential impacts on threatened and endangered marine mammals (FOEI, WWF, Pacific Environment)
PPR 7/12/4 - Refining the title and scope of a new output on discharge of liquid effluents from EGCS (FOEI, WWF and Pacific Environment)

The impacts of EGCS washwater discharges on port water and sediment (CE Delft)

Report by the expert board for the environmental impact assessment of discharge water from Scrubbers (Japanese Ministry of Land, Infrastructure, Transport and Tourism)

Compilation and Assessment of Lab Samples from EGCS Washwater Discharge on Carnival Ships (DNV GL)