Cruise ships dump more than one billion litres of grey water off B.C.'s coast every year, a new study by World Wildlife Fund Canada charges.
The study found 1.54 billion litres of grey water were generated by ships off the B.C. coast in 2017 — the equivalent of more than 600 Olympic-size swimming pools. The vast majority, 1.37 billion litres, came from cruise ships.
Grey water — the drainage from dishwater, galley sinks, and showers — may contain contaminants ranging from grease, oil and flame retardants to disinfectants, fecal coliform and micro-plastics.
Because of limited storage on vessels, it's common practice for ships of all sizes to discharge grey water into the ocean, WWF says.
“There are several environmental impacts of grey water dumping, including the potential for nutrients in the liquid to foster excessive algal growth, leading to dead zones for aquatic life,” says WWF spokesman Andrew Dumbrille. “Grey water can also contain oil and grease that suffocates fish by coating their gills, and particulate matter that chokes species like lobster, crab and sponges.”
Regulations governing grey water dumping in inland waters only cover the area up to three nautical miles of the coast. Beyond that, there are no requirements, the WWF says.
“We urge Transport Canada to put additional regulations in place around grey water dumping. Some companies voluntarily go beyond what is required, but much more is needed across the industry. With 90 per cent of all grey water likely produced on cruise ships, transparency can help customers make a difference by supporting companies that keep ocean health in mind,” says Dumbrille.
The study was conducted by Vard Marine Inc., and looked at the types of vessels transiting Canadian waters from Washington to Alaska, their routes, average number of passengers and grey water generated.