Why You Should Never Order Tap Water on a Plane

It’s important to hydrate when flying, but you’re going to want to stick to bottled water.

The one thing people always tell you to do before you fly is to hydrate. Hydrate at home, hydrate in the airport, and hydrate on the plane. Well, you might want to stock up on water while you’re still on the ground because a study revealed that the tap water on planes isn’t very sanitary.

The Hunter College NYC Food Policy Center and DietDetective.com released an Airline Water Study investigating the quality of the galley water on 11 major airlines and 12 regional airlines. These are some other things airplanes aren’t cleaning as they should.

The results showed that Alaska Airlines and Allegiant Air have the best water quality while JetBlue and Spirit Airlines have the worst. Each airline was given a “Water Health Score” of 0 to 5 (0 being the lowest rating, 5 the highest) based on the fleet size of the airplane, Aircraft Drinking Water Rule violations, and the presence of E. coli and coliform in the water samples. If an airline got a score of 3 or higher it means that they have relatively safe, clean water.

Back in 2011, the EPA instituted the Aircraft Drinking Water Rule (ADWR) to “ensure that safe and reliable drinking water is provided to aircraft passengers and crew,” but that rule doesn’t go far enough. The tap water served to customers and used to make coffee in tea is stored in water tanks that are not cleaned very often causing the water to be contaminated with bacteria. Read up on the airlines with the best and worst food.

A year after they put that rule in effect, one out of every ten planes still tested positive for coliform in their water. The Airline Food Study released in 2019 showed that not much has changed. You might think that the water tanks would be emptied and cleaned at least once a day but instead, they sit for long periods of time in contaminated tanks.

These are the “Water Health Scores” for all the major airlines tested in the study:

  • Alaska Airlines: 3.3
  • Allegiant Air: 3.3
  • Hawaiian Airlines: 3.1
  • Frontier Airlines: 2.6
  • Southwest Airlines: 2.4
  • Delta Air Lines: 1.6
  • American Airlines: 1.5
  • United Airlines: 1.2
  • JetBlue: 1
  • Spirit Airlines: 1

So, make sure you stock up on bottled water (and coffee or tea) while you’re still in the airport—it could save you from a ruined vacation. Next, read about these 18 other things you should never do on an airplane.

Morgan Cutolo
Morgan is the Assistant Digital Managing Editor at Reader’s Digest. She graduated from the University of New Hampshire in 2016 where she received her Bachelor of Arts in Journalism. When she’s not writing for rd.com or keeping the 650+ pieces of content our team produces every month organized, she likes watching HGTV, going on Target runs, and searching through Instagram to find new corgi accounts to follow.