Americans to Drink More Bottled Water Than Soda This Year Concerns about health and convenience are behind the growth, experts say.

 -- Perhaps it's a sign of Americans' increasing concern with health, a growing laziness about filling a water bottle at the tap, or even a fear of tap water contamination.

But Americans are this year for the first time expected to purchase more bottled water than traditional carbonated sodas.

Projections from market research firm Euromonitor show that this year each American will on average purchase 27.4 gallons of bottled water, more than the 26.2 gallons of carbonated sodas.

The gap has been closing for some time. Last year, Americans bought just 0.3 gallons more soda than water per person, down from a 1.9 gallon difference in 2014.

Euromonitor expects the gap to grow in favor of bottled water going into the future, with each American projected to buy 29.8 gallons of the healthy stuff in 2020 compared to 24.1 gallons of soda.

What’s driving this trend isn’t totally clear.

Bloomberg News, who first reported the trend, suggests that recent incidents of tap water contamination -- most notably in Flint, Michigan, where people were sickened by lead in the municipal water supply -- may be driving people towards bottled water.

However, industry leaders who spoke to ABC News thought that it was more about consumers seeking a healthy lifestyle and greater convenience.

Chris Hogan, a vice president at the International Bottled Water Association, told ABC News that fears of tap water contamination "may play a role in some people’s concerns more recently, but this is an ongoing shift that’s been in the works for several years.”

He added: “More than anything it’s a consumer shift from less healthy food choices to more healthy food choices.”

Additionally, he said, “A lot of what we’re eating now is while we’re on the move or food that we take with us.”

Gary Hemphill of the Beverage Marketing Corporation agreed.

“If you look at the U.S. beverage market, and I suppose it’s true globally as well, people are moving towards healthier options,” he said.

The trend of increased bottled water consumption goes back to the early 1990s, he said, when beverage companies began selling single-serving bottles of water for mass consumption.