Royal Caribbean reveals how it turns sea water into something thousands of passengers drink

No matter where its vessels are in the world, one thing is for sure when it comes to Royal Caribbean: it's cruise ships won't run out of water.

Whether the middle of the night, first thing in the morning, or sitting down for lunch, water is always readily available.

But how? You're on a huge floating metal box in the middle of the ocean, with thousands of other passengers also using up their own segment of H2O. And that's alongside keeping the swimming pools, taps, and showers running.

Royal Caribbean's largest cruise ship, Icon of the Seas, has six water slides to run, as well as an indoor diving arena. And with capacity for almost 10,000 crew and passengers combined, that's a lot of people using it all at the same time.

Well, there's one genius way they make sure they never run out.

Royal Caribbean does its best to save water (Getty Stock Images)

Making sea water drinkable

That's right. You're drinking sea water.

But the company states that it uses 'state-of-the-art technology to produce our own water supply' so that nasty tasting salt water is actually perfectly okay to consume.

“Water is as crucial to a ship’s operation as fuel,” says Nick Rose, Royal Caribbean’s environmental programs expert.

“We’re able to get really creative in conserving and reusing it.”

They're not messing about with this, either. In total, more than 90 percent of water on a Royal Caribbean cruise ship - as well as water on its private islands such as CocoCay - is created on board through a scientific processes known as steam evaporation and reverse osmosis.

CocoCay island is owned by Royal Caribbean (Royal Caribbean)

The science

Also known as flash evaporation or steam desalination, steam evaporation is a process that uses steam and heat from the ship’s engines to boil sea water.

"The water evaporates, leaving the salt as a byproduct," Royal Caribbean says.

"The now fresh water is then condensed back into distilled purified water."

As well as steam evaporation, there is reverse osmosis. This process doesn't use heat; instead it uses an 'even lower-energy method to push saltwater through microscopic membranes', RC says.

"It’s so small, only clean water can get through," says Rose.

As a result, all salt and possible contaminants remain blocked on the intake side of the chamber while the water that passes through is mineralised for flavour, according to U.S. Public Health Service guidelines.

All the ways Royal Caribbean ships have embarked on environmentally-friendly policies (Royal Caribbean)

Saving water

As well as the two methods above, Royal Caribbean have embarked on something called aeration.

This is the process of forcing air through shower heads and sink faucets to allows for ample water pressure in every bathroom.

“We use air to create pressure rather than forcing water out at high volumes,” explains Rose. “It lets our guests shower comfortably while saving water. It’s a total win-win.”

It uses less water, basically. Something we can all agree is a good thing. This is also done with the laundry services, with all condensed water collected from air-conditioning units to reuse when washing clothes or bedding.