5 Things You Need to Know About Cruise Ship Pollution

Oct 5, 2010· 1 MIN READ
A six-time grantee of the National Geographic Expeditions Council, Jon writes about all things ocean.

Despite declines of 15 to 20 percent in the past couple of years, cruise ships are still a $27-billion-a-year industry. More than 18 million people cruise the world at least once a year.

In December, Royal Caribbean International will launch the biggest cruise ship ever, the 5,400 passenger Oasis of the Seas, a $1.2 billion floating behemoth that features 2,700 staterooms, 16 decks and two dozen restaurants.

There are at least five reasons why you mght not want to be in water that close to a cruise ship. (Photo: Gary Hershom/Reuters)

Obviously, when mega-ships cruise the seas, some things get left behind.

Rules and regs dictate just what types of waste these boats are allowed to dump, but the off-load is pretty sickening, legal or not.

Here’s the short list of what cruise ships big and small dump in their wakes:

1. More than 30,000 gallons of treated human waste (or blackwater) are flushed into the sea every day, causing bacterial growths and contaminating fisheries.

2. Waste generated by laundries, showers, sinks and dishwashers (graywater) is the biggest pollutant created by the industry; roughly 225,000 gallons of gray water are treated and dumped into the ocean every day.

3. Roughly 75 to 80 percent of the trash generated aboard ships—including glass, plastic bottles, cans, paper, cardboard and food waste, or about two pounds of solid waste per passenger every day—is incinerated on board, the ash dumped into the sea. The rest is taken back to port, but often overwhelms local landfills... so it ends up dumped into the ocean.

4. A variety of toxic wastes are generated onboard, ranging from photo processing to dry cleaning chemicals. In a perfect world, these chemicals would be dumped only when the ships are docked. Unfortunately, it's definitely an imperfect world.

5. Bilge water is a mix of seawater and oil from routine maintenance, which ends up collecting at the bottom of the ship. An average ship generates eight tons of the oily combo every day. While it is supposed to be stored and dumped onshore, a number of cruisers have been caught dumping it at sea.