The findings come nine years after Environmental Protection Agency launched a major campaign to combat contaminated water. What they found: It's not much better than it was in 2004, when sample tests were first taken.
According to NBC, the EPA sampled water on 300 planes in 2004 and discovered 15 percent - one out of every 10 - tested positive for coliform.
The presence of coliform is a key indicator that bacteria may be in the water. The EPA characterized that percentage as "high" and vowed to push reforms.
But data from 2012 shows that 12 percent of commercially owned and flown planes in the US had water that tested positive for the same bacteria. Again, that's about one in every 10 airplanes.