Environmental Science & Engineering - www.esemag.com - January 2002
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The Côte D'Azur was lovely - but are ocean liners polluters?

By Tom Davey, Editor and Publisher

Leaving the cruise ship by ship's tender for Nice. ES&E photo - T. Davey

Eons ago, we sailed from the UK to Australia via the Suez Canal. Virtually every evening, we saw crew members heaving cases of bottles, cans and other garbage over the stern. After being dumped overboard, the garbage laid a trail, bobbing amid the powerful wake of the liner's screws before sinking beneath the waves. Some years ago I wrote an article in ES&E called: Girdling the globe with garbage. In the piece I speculated that future marine archeologists might plot the trans-oceanic era of our civilization by the wine bottles and other non-biodegradable debris laid down by the many ocean liners sailing the same routes around the world.

Few of us realize that such liners, at the very zenith of their power, were actually endangered species as a maritime version of Darwin's theories was emerging on the drawing boards in Seattle.

In economic survival of the fittest, powerful ocean giants like the Queen Mary, the Queen Elizabeth I, the Normandie and the United States of America, were quickly displaced by the arrival of the Boeing jumbo jets. But the evolutionary process continued. While jet planes caused the demise of trans-oceanic travel, huge passenger ships - bigger than ever - evolved in the form of cruise ships. Close up, they look more like aquatic skyscrapers than ships.

Travel by ship staged a remarkable comeback with the advent of cruising. Now, travellers can leisurely visit both natural and architectural wonders of the world. They can visit the Acropolis, the Colosseum, the Sistine Chapel, or the splendours of the beaches of the Côte D 'Azur and many North African countries. In North America too, passengers can view great aquatic species such as polar bears and whales.

But what are the environmental impacts of cruising? We recently enjoyed a Mediterranean cruise on a ship which had a capacity of some 1,100 passengers and 365 crew, a medium-sized cruise ship by today's standards.

The Mediterranean has been part of much of our history and it is littered with historic artifacts. Alexander The Great built the city which bears his name in Egypt, along with a great lighthouse on its shores whose remains are being researched by underwater archeologists. Greek Triremes once battled Spartan warships around 415 BC, as later Roman ships did battle with the Phoenicians. Nelson destroyed Napoleon's warships in the Battle of the Nile, and the Italian Fleet was largely destroyed at the Battle of Matapan during WW II. Many Royal Navy warships lie at the bottom of the Mediterranean after encounters with U-boats. Most passengers en route to seeing the land-based wonders of ancient Europe are unaware that they are sailing across a sea whose depths contain artifacts equally rich in history.

We saw no sign of the overboard dumping which had gone on in earlier years, indeed, no sign of any environmental malfeasance save for some black smoke from the funnel from the diesel engines. But even this ship - dwarfed alongside some modern cruise ships when we docked - had to take on enough food, water and fuel to sustain a small town. (And let it be admitted there were large amounts of food and drink available to restore pasengers following rigorous touring treks.) While we saw no apparent signs of dumping of any kind on our seven day trip, we wondered where and how the wastewaters were being handled?

Cruise ship in Vancouver takes wildlife enthusiasts to see whales and other attractions off the spectacular west coast. Photo - T. Davey

Closer to home, over one million passengers a year booked cruises on more than 300 voyages that traced the Pacific coastal routes between British Columbia and Alaska. The popular trips to view whales and other exotic wildlife have been growing steadily for almost 20 years and last year contributed about $508 million to the BC economy. It is estimated that on a one-week trip, a typical cruise ship might generate some 794,936 litres of sewage a day. During the peak summer season, with an average 20 ships carrying 2,000 passengers and crew each (approximately twice the passenger capacity of our cruise ship), the daily discharge has been roughly estimated at some 9.5 million litres, the equivalent of the entire amount of sewage discharged by a small city.

Discharges of so-called 'grey' water usually refer to wastewater from sinks, showers, dishwashers and laundry facilities, but may also contain detergents, oil, pesticides and medical wastes. In addition to sewage, grey water and diesel exhaust, today's cruise ships also discharge toxic chemicals from dry-cleaning, photo processing and other services.

The Mediterranean is a pond compared to the Pacific which is the largest ocean in the world by far, yet west coast pollution from cruise ships is now being alleged. The West Coast Environmental Law Association is on record as saying that Canadian laws governing cruise ships on the Inside Passage from Vancouver to Alaska, are not only weak but inadequately enforced.

John Hansen, president of the Vancouver-based North West Cruise Ships Association, has stated that nearly one-quarter of its 22 ships that travel BC's renowned Inside Passage, have water treatment devices aboard that bring sewage water to near drinkable quality prior to discharge. Even so, west coast cruise ships which treat their wastewaters are still a minority.

Most of the modern day passengers seem blissfully unaware of any environmental impact which might result from their travels. We have come a long way - literally and metaphorically - from our early voyages where garbage was simply heaved over the stern without any comment from passengers. But I wonder what the environmental burden would be if 2,000 vacationers travelled the same distances by automobile - or by airlines - and stayed in motels for two weeks? In physics there is no 'free lunch', is there?

Tainted waters

With an average of 2,000 passengers and crew on every trip, the six sources of cruise-ship pollution increase as the industry grows:

Air pollution

Sewage
Human waste

Grey water
Wastewater from sinks, showers, galleys and laundry may contain detergents, cleaners, oil and grease, metals, pesticides and medical waste.

Oil and bilge water
Fuel, oil, oily water, on-board spills collected in the bilge located in the bottom of the cruise ship's hull.

Hazardous wastes
Toxic chemical waste from dry cleaning, photo processing, paint and solvents, batteries, fluorescent lamps and other sources.

Solid wastes
Plastic, paper, wood, cardboard, food waste, cans or glass.

Source: West Coast Environmental Law Association

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