My family took a Caribbean cruise this summer. How bad for the environment was our vacation?
Like any other oceangoing vessel, a cruise ship can affect both the water and the air with its waste products. First, there's the issue of bilge water, which collects in the lowest part of the ship and often contains oil from leaky engines as well as other contaminants. Then there are the air pollutants that fly out from the ship's smokestacks; these include particulate matter, sulfur dioxide and nitrogen oxides.
Cruise ships pose additional environmental risks compared with other vessels because a large ship carries thousands of passengers, each of whom produces a waste stream that can end up in the ocean. In a recent EPA survey of boats operating in Alaska, cruise ships reported generating an average of 21,000 gallons of sewage a day. Those ships also produced a daily average of 170,000 gallons of gray water, the stuff that drains from sinks, showers and washing machines.