What are Scrubbers?
Scrubbers are ‘exhaust gas cleaning systems’ that use seawater or freshwater to remove sulphur and other contaminants from a ship’s air exhaust when heavy oil fuel is used. This process reduces emissions released into the air; however, scrubber wash water is discharged into the ocean and can be toxic to marine life. The use of scrubbers effectively turns air pollution into ocean pollution.
Why do ships use Scrubbers?
Regulations by the Internation Maritime Organization (IMO) and the North American Emissions Control Area (ECA) have attempted to reduce air pollution by mandating lower sulphur emissions - to 0.5% and 0.1% respectively. The intent was to have ships switch to using cleaner fuels, such as very low sulphur fuel oil or distilled low sulphur marine gas fuel.
Unfortunately, IMO guidelines allow the use of scrubbers to meet their reduced emission mandates. Heavy oil fuel is about half the price of low sulphur fuel and many ships have opted to install scrubbers instead of switching to cleaner fuels. Most cruise ships using Victoria as a port of call use heavy fuel oil with scrubbers. The installation of scrubbers reduces costs and increases profits for ship owners with unknown future health and environmental implications and costs for their host communities.
Do Scrubbers increase Ocean Pollution?
It appears so. Contaminants in scrubber discharge wash water include metals, hydrocarbons, sulfurous and nitrous acids, and turbidity that can contribute to long-term contaminant loading to the marine environment.
The IMO’s Task Team on Exhaust Gas Cleaning Systems stated in 2019: “In terms of total amounts of contaminant discharges through EGCS, it appeared that large scale uses of these systems may lead to deterioration of environmental status, especially in the ecologically vulnerable and sensitive areas such as coastal waters, semi-enclosed seas and also in ports and harbours”.
In 2019, the Port of Vancouver commissioned a modelling study to better understand the environmental impact of scrubber wash water discharge in Burrard Inlet. The study showed that scrubber wash water discharge could result in concentrations of metals that exceed thresholds set for the protection of marine aquatic life.
The Port of Vancouver and the Port of Prince Rupert have banned scrubber waste discharges at anchorage and at berth. They require ships to either hold wash water on board, switch to low sulphur fuel or connect to shore power.
Do Scrubbers eliminate Air Pollution?
No. Researchers at the International Council for Clean Transportation found that ‘even with scrubbers, ships will continue to emit air and climate pollution emissions such as particulate matter, sulfur oxides, nitrogen oxides, black carbon and carbon dioxide’. A 2018 study by the University of California for the California Air Resources Board indicated that scrubbers do not provide the same air quality reductions for particulate matter as compared to vessels using low sulphur fuel. Locally, there continues to be concern about ultrafine particulate matter and volatile organic compounds.
How have Countries and Ports reacted to the use of Scrubbers?
Many governments and ports around the world have restricted the use of scrubbers, including California, Norway, China, Saudi Arabia, Portugal, Sweden, Malaysia, Dublin, and Seattle.
What about Canada?
In 2020, Environment and Climate Change Canada funded an analysis of the use of scrubbers by the International Council on Clean Transportation (ICCT). ICCT recommended an immediate prohibition on using scrubbers and warned of negative effects of scrubber discharges on marine life.
In 2023, Canada issued an Interim Order Respecting the Discharge of Sewage and the Release of Greywater by Cruise Ships in Canadian Waters. The measures state that sewage and greywater cannot be discharged within 3 nautical miles of shore and that any sewage or greywater discharged between 3 and 12 nautical miles from shore should not leave a sheen or residue on the surface. Unfortunately, the Order lacks any prohibition of scrubber wash water discharges by cruise ships in Canadian waters.
Locally, the ports of Vancouver and Prince Rupert - which are federal agencies - have banned scrubber wash discharges at anchorage and berth; however they have not yet banned scrubber discharges from main vessel engines while ships are maneuvering or transitioning in port.
What about Victoria?
The cruise ship terminal in Victoria currently has no scrubber wash waster discharge restrictions in effect. Most cruise ships visiting Victoria have scrubbers on board.
Our health and the environment cannot wait. Cruise ships should be required to use lowest sulphur fuels while transitioning, maneuvering and docking at Ogden Point in Victoria Harbour. Scrubber wash water discharges should be banned, as they are in many ports and countries around the world.