8 Ways Cruise Ships Can Cause Marine Pollution

No road travelled is without problems. At sea, when talking about marine transport, there are no clear-cut roads, but problems in the form of pollution exist and persist, threatening our marine environment badly.

The shipping industry that fulfils more than 90 per cent of trade across the world with the help of around 90,000 marine vessels contributes heavily to global pollution and climate change.

The studies indicate that the shipping industry is responsible for large quantities of pollutants being omitted, including over three per cent of global carbon dioxide emissions in the world. Being one of the worlds’ most polluting sectors, the increase in marine transport in huge magnitudes in these days also increase ship pollution substantially.

Within the shipping industry, the cruise industry makes no difference. Though representing a small fraction of the industry, cruise ships, as much as the entertainment they provide, are also a source of great pollution in the oceanic and marine areas like the commercial vessels.

In 2018, the cruise industry offered service to more than 26 million customers and it is expected the industry will continue to grow in the coming years. Environmental groups state that the passenger’s carbon footprint triples when one opts a cruise journey as these ‘floating cities’ produce around 15 gallons of hazardous chemical waste every single day.

Though there are maritime environmental protection agencies and marine organisations working to resolve issues, there is still a lot that needs to be done.

Here are the major ways in which the cruise ships threaten the marine environment and contribute to global pollution.

Ballast Water Pollution

Cruise ships, like other big vessels, use a huge amount of ballast water to stabilise the ship while travelling. As these vessels travel for a longer period, the Ballast water is often filled from one region and discharged in another whenever required. The amount of ballast water released typically is around 1,000 metric tons. This discharge of the ballast water from the cruise ships is a major cause of cruise pollution.

Since the ballast water contains microbes and micro-organisms in addition to vegetation and other sea-animals, the pollution aspect is mainly caused by the local species and marine life. One very good example of such ecological damage would be the huge swell of the population of jellyfish in the Black Sea.

Related reading:

How ballast water treatment system works?

Air Pollution

As we are all aware, poor air quality is one of the major global health hazards at present as, according to the World Health Organisation, 4.2 million people die due to air pollution. Just as the exhaust tanks in vehicles emit waste fumes and noxious air, the engine of the cruise ships also emit such unwanted air.

Related reading:

What are NOx emissions from ships?

What are SOx emissions from ships?

The scope of the gases emitted from the vehicular emissions on the road and the cruise ship emissions on the sea differs hugely, leading to the pollution of immense proportions in the oceanic areas. Similarly, recent research also found that the air on the aft areas of cruise ships, particulate matter pollution in detail, is as polluted as the air in the major polluted cities in the world, such as Beijing.

Related reading:

10 Technologies for controlling NOx and SOx emissions from Ships?

Noise pollution

The noise produced by the passing ships affects badly the environment as it disturbs the marine ecosystem. Unlike other ships, Cruise ships contribute heavily to marine noise pollution as the windows of noise pollution are high in cruise ships.

In addition to the noise pollutions from the ship’s machinery, cruise ships produce more noise thanks to the entertainment activities on board. These noises disturb the marine animals and mammals, including killer whales and dolphins, whose sensitive hearing gets harmed and debilitated, often leading to their unwanted death and an overall loss to the eco-system.

Grey Water Pollution

Unlike other vessels, cruise ships dump more wastewater offshore (after passing through a treatment plant), especially Grey water that comes from sinks, laundries, showers and galleys abroad the vessel. Thus, even the most regular activity onboard the cruise ship, such as cleaning utensils and doing the laundry, causes cruise ship pollution.

Classified under the head of the greywater, this water accumulation contains not just harmful chemicals but sometimes even metals and minerals too. The potency of greywater harming the marine environment is greater because of its high concentration in the oceanic waters. Studies show that a large cruise ship releases around one million gallons of grey water during a single week’s voyage.

Blackwater/ Sewage Pollution

What happens when someone flushes the loo on a cruise ship? The answer is very simple. The ship dumps human waste into our oceans (after passing through sewage treatment plant). And, we have larger cruise ships that can accommodate up to 6680 passengers and 2200 crew members.  Yes, the next huge cruise pollution cause is from sewage.

Classified as Blackwater, around 210,000 gallons of human sewage is deposited into the ocean by cruise ships during a week’s voyage. Sewage includes waste from the toilets and the health facilities provided in the cruise ship. Such sewage is rich in bacteria and algae adversely affecting the oceanic life-forms and the entire marine eco-system.

Chemical Pollution

The entry of chemicals from the cruise ships to the oceans through the grey water or the black water channels is another threat the cruise ships make to the marine ecosystem.

Cruise ships emit toxic chemicals from batteries, dry cleaning and industrial products, chemicals for daily operations, and several other chemicals past their expiry, polluting the waters the ships travel. Environmentalists argue that these chemicals possess a huge threat to the lives of the marine creatures and life-forms.

Oil Pollution/ Bilge Oil Pollution

Oil pollution from the shipping industry is considered to be the main reason for the increased level of marine pollution. Cruise ships, huge in size compared to other vessels, end up burning more heavy fuel oil, one of the dirtiest fossil fuels available in the market. This oil contains dangerous levels of sulfur and heavy metals etc.

It is estimated that the cruise ships use, on average, 150 tons of heavy fuel oil every day. With the bilge oil mixing with oceanic water, the use of this oil causes serious marine pollution. Faulty engine system and improper repair work are two areas through which oil could leak and mix with the oceanic water. Collisions and accidents also act as a reason for such oil pollution.

Related Reading – 10 methods for oil spill cleanup at sea

Solid Waste Pollution

It is estimated that the cruise ships contribute 24% to the total solid waste generated by maritime traffic across the world as one of such luxury vessels can produce seven tons of garbage and solid waste in a single day.

The solid waste materials that a cruise ship emits include paper, cardboard and aluminium etc. Such materials end up forming unwanted debris on the surface of our oceans, posing large scale threats to the marine plants and creatures.

Related Reading – Tips of reducing and recycling waste at sea

Destruction of Coral Reefs

Cruise ships are a serious threat to coral reefs and its related organisms. As tourist’s vessels, the entry and anchoring of cruise ships on disturbed and undisturbed areas of coral reefs across the world have resulted in several incidents that involve the destruction of these natural wonders.

These accidents also affect the rich ecological integrity and biodiversity depended on these coral reefs.  In 2017, British cruise ship MS Caledonian had crashed onto the pristine coral reefs of Indonesia, destroying 17,222 square feet of coral reefs and causing more than $19 million in irreparable damage.

Physical damages to marine life

In addition to the air and water pollution these cruise ships cause, Whales and Dolphins are also victims of the increasing traffic of these ships. These massive ships are responsible for injuring, often killing, marine lives, particularly fin whales, killer whales and humpback whales.

Considering the risks and the damages caused to the marine environment, proper resolutions have been laid down by countries across the world to protect the oceanic surroundings.

Slowly and steadily, even cruise shipping conglomerates have begun to understand the importance and necessity of preserving the marine eco-system. For the time being, a better cruise shipping experience with the necessary caution and care for the marine life-forms still remains a dream to be realized and attained.  Hopefully, it will be, in the days and years to come.

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