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If you read our recent blog, you’ll be well aware of the detrimental impacts cruise ships are having on the planet.

From toxic waste and pollution being dumped into the seas, to onboard journeys being more carbon intense than a short haul flight, there are plenty of reasons why the cruise ship industry is falling short when it comes to green travel.

But for those cruise ships that claim to be more eco-friendly than their predecessors, offering more ‘sustainable’ cruise tours around the world, do these issues still apply?

‘Sustainable’ fuel

The biggest reason some cruise ships are now claiming to be more sustainable is largely down to investing in liquefied natural gas (LNG) as an alternative to traditional heavy marine fuels (mostly diesel).

While this is considered in line with international standards regulating emissions from ships, the reality is it remains a highly polluting source of fuel. Made up of methane, a greenhouse gas 80 times more potent than CO2 in the short term, it’s up to 30 times worse in the long term… bringing new (and potentially worse) climate problems in the future.

The problem is regulations don’t necessarily reflect these issues, meaning ships like Icon of the Seas, the largest cruise liner in the world, can still claim to be 24% more carbon emission efficient than required by global shipping regulator the International Maritime Organization (IMO).

And while companies, like Norway’s Hurtigruten, are taking bigger steps to address these issues by moving to sources like biofuels and hybrid batteries, there are still some lengths to go when trying to hit zero emissions goals for ships on longer journeys.

Sewage treatment… or lack of

Even for those businesses that are getting top marks for air pollution on the Friends of the Earth scorecard, scores for sewage and water discharge still remain low – proving treatment remains a massive problem.

With hundreds, or even thousands, of people on board many of these ships, treating sewage isn’t easy and options remain limited. The US Environmental Protection Agency has estimated that a 3,000-person cruise ship generates 176,400 gallons of sewage per week (adding up to over one billion gallons of sewage a year for the industry), and lenient rules – combined with lack of enforcement – can see vulnerable environments become dumping grounds.

According to the International Convention for the Prevention of Pollution from Ships (MARPOL) raw sewage can be discharged just 12 nautical miles from land, as the high seas are considered to be capable of assimilating it through natural bacterial action. For treated sewage, it’s just three miles.

Even when sewage is treated, though, treatment standards at sea are often far weaker than those required on land, and, while some companies promote ‘advanced waste-water treatment systems’, they are not required everywhere, and aren’t regularly monitored by independent authorities. In fact, a 2017 study concluded that 97% of ships tested did not meet sewage effluent requirements, despite using approved plants.

For the oceans, untreated sewage can lead to major issues, including toxic algae blooms that smother ecosystems, while people using marine resources can contract a range of illnesses from contaminated waters.

Wildlife disturbance & collisions

Boat activity on the water, regardless of size, can an impact on wildlife. From the biggest cruise ships to the smallest ones, there’s always a higher risk of negatively impacting the environment around them… whether they are an ‘eco’ cruise ship or not.

For example, underwater noise pollution is a major problem associated with the cruise industry, because sound travels four times fast in water and can affect marine animals in different ways.

It can be a real threat to marine life – and can sometimes even be fatal. As ‘last chance tourism’ (coined for seeing places before they disappear as a result of climate change) sees eco cruise ships heading deeper into remote regions, the noise risk becomes much higher. This can impact marine animal behaviour, displace them from critical habitats, cause stress and hearing loss, and mask an animal’s ability to produce and detect important sounds.

But noise isn’t the only issue. In fact, collisions are another major concern, caused when ships travel the same routes as marine animals, or get too close to them for guests to see on board. As in the case of a humpback whale known as “Snow”, who was found floating in Alaska’s Glacier Bay National Park, dying of massive trauma to her skull and cervical vertebrae, the injuries were consistent with a vessel collision. The incident led back to Princess Cruise Lines, who eventually pleaded guilty to failing to operate its vessel, the Dawn Princess, at a slow and safe speed while near humpback whales.

While the company was fined for breaking the law, it turned out that passengers and crew spotted humpbacks near the ship, but there was no move by ship to change course or speed.

This is not a rare example. It’s estimated 20,000 whales are killed every year globally by vessel strikes, and, with up to 75 species (including dolphins, sharks, seals, otters and more) recorded to be impacted by strikes, the total number of all marine animals hit in the ocean is likely far, far higher. And this can largely be down to the fact that it can take several miles for a large ship to slow down or come to a full stop, making it incredibly difficult to stop in an emergency.

Our advice? Responsible wildlife watching can be possible on the water, if only from a small vessel, at distance and with low speed (and, of course, the right management!).

The verdict

Even just looking at the issues around fuel, wildlife disturbance and waste prove that truly ‘green’ cruising is still a long way off. Until batteries can power ships for more than just a few hours, and better regulations around sewage are introduced (and properly regulated by independent bodies), the eco-conscious traveller should probably avoid the high seas for the foreseeable.

There are some positives; we’re pleased to see many cruise businesses stepping up to the plate when it comes to reducing plastic waste and moving to more planet-friendly alternatives. That said, when facing a global plastics crisis it is, quite literally, the least they can do.

In the meantime, we’ll be keeping a close eye on those greenwashing claims, and debunking myths whenever we can.

Keep following us on Facebook and Instagram to keep up with our latest articles and news – and don’t forget to share…

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