The amount of untreated grey water dumped in Canadian Arctic waters is projected to double by 2035 if left unregulated, according to a new report commissioned by World Wildlife Fund Canada.

As climate change makes the region more accessible, grey water from vessels’ galleys, showers and laundry is being released in increasing amounts into the fragile Arctic marine ecosystem, said WWF Canada. Passenger vessels, such as cruise ships, produce about 250 litres per day per person of grey water and cargo vessels produce about 125 litres per day per person.

Grey water can contain nutrients such as nitrogen and phosphorus, oil and grease, detergent and soap residue, metals (such as copper, lead and mercury), bacteria, pathogens, hair, organic matter including food particles, suspended solids, bleach and pesticide residues.

The potential environmental impacts of grey water include shellfish contamination, algal blooms, lowered oxygen levels in the ocean and introduction of microplastics, said WWF Canada.

Subscribe to our Newsletter!

The latest environmental engineering news direct to your inbox. You can unsubscribe at any time.

Impact of grey water on food security in the Arctic

Communities in the Inuvialuit Settlement Region, which is located in Northwest Territories, and the North Slope Region of the Yukon, are happy to see increasing tourism in the Arctic and rely on shipping for supplies, said Hans Lennie, secretary-treasurer of the Inuvialuit Game Council.

However, the ocean is an important food source for the region and Lennie said he is concerned about the impact of pollution on food security.

Map of the Inuvialuit Settlement Region. Photo credit: The Joint Secretariat – Inuvialuit Settlement Region

“Untreated grey water can contaminate shellfish and could create toxic algae blooms that have the potential to jeopardize our food security,” said Lennie. “As shipping grows in the Arctic, it’s important that regulations are changed to stop the dumping of grey water into the ocean.”


WWF Canada said that although the impacts of grey water are similar to sewage, ships passing through Arctic waters in Canada are not required to adhere to any specific regulations for grey water and ships are not monitored for dumping grey water into the sea. Transport Canada rules for grey water are much more stringent for waters below the 60th parallel.

map of grey water concentrations in the Arctic
Grey water concentrations map.

The WWF Canada report argues that regulations governing grey water disposal in the Arctic are overdue for an overhaul as shipping traffic and grey water disposal is expected to increase rapidly in the next 20 years.

“Grey water can have many harmful impacts on the ocean, including introducing invasive species, metals, bacteria and microplastics,” said Melissa Nacke, specialist for arctic shipping and marine conservation at WWF Canada. “It doesn’t make any sense that the fragile Canadian Arctic environment receives less regulation and protection than southern waters and neighbouring Alaska, and we want that to change.”

Report highlights
  • The report was prepared by Vard Marine Inc., and builds on a previous, similar greywater analysis from 2015.
  • This 2018 report presents a baseline for waste in the region in 2016 and provides projections for the quantities, types and areas of grey water concentration in the Canadian Arctic in 2025 and 2035.
  • The report shows that, due to the large number of passengers on cruise ships and their higher water use per person, tourism is projected to generate the most grey water by 2035, especially in the Northwest Passage.
  • Ships used for mining exports and fishing spend much more time in the Arctic, so even though they have fewer people onboard and lower levels of water use, they are also large contributors.
  • The report also points to various treatment options that could be used on ships to eliminate environmentally harmful substances.

For more information and to read the complete report, visit:



Please enter your comment!
Please enter your name here