The study, released by DietDetective.com and the Hunter College NYC Food Policy Center, ranks ten major and 13 regional US airlines mainly by the quality of water they provided onboard its flights. Each airline was given a "Water Health Score" (5 = highest rating, 0 = lowest) based on ten criteria, including fleet size, ADWR violations, positive E. coli and coliform water sample reports and cooperation in providing answers to water-quality questions. A score of 3.0 or better indicates that the airline has relatively safe, clean water.

Safest water in the sky

Alaska Airlines and Allegiant win the top spot with the safest water in the sky, and Hawaiian Airlines finishes No. 2. The airlines with the worst scores are JetBlue and Spirit Airlines, the study shows. Except for Piedmont Airlines, regional airlines need to improve their onboard water safety.

Regulations

Unhealthy water violates the federal government’s Aircraft Drinking Water Rule (ADWR), which was implemented in 2011 and requires airlines to provide passengers and flight crew with safe drinking water. The ADWR requires airlines to take samples from their water tanks to test for coliform bacteria and possible E. coli. Airlines are also required to disinfect and flush each aircraft’s water tank four times per year. Alternatively, an airline may choose to disinfect and flush once a year, but then it must test monthly.

Scores At-a-Glance

Major Airlines
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
Regional Airlines
Piedmont Airlines: 4.33, Sun Country Airlines: 2.78, Envoy Air: 2.11, GoJet Airlines: 2, Trans States Airlines: 1.78, Compass Airlines 1.22, PSA Airlines: 1.22, SkyWest Airlines 1.11, Endeavor Air: 0.78, Air Wisconsin Airlines: 0.68, ExpressJet Airlines: 0.56, Republic Airways: 0.44
The study’s findings can be found here.
Text source: New York City Food Policy Center