Brian Smithson/Flickr For the first time ever, Americans drank more bottled water than soda in 2016.

After a decades-long growth streak, bottled water sales by volume surpassed sales of soft drinks last year. Total bottled water volume grew nearly 9% in 2016, reaching 12.8 billion gallons, according to research and consulting firm Beverage Marketing Corporation.

That's 39 gallons of bottled water per person, compared to 38.5 gallons of soda. According to Beverage Marketing, per capita soda consumption regularly exceeded 50 gallons in the late 1990s and early 2000s.

The reversal of fortunes has been traced to Americans' changing tastes and growing concern about sugary beverages.

"Bottled water effectively reshaped the beverage marketplace," Michael C. Bellas, Beverage Marketing's chairman and CEO, said in a statement. "When Perrier first entered the country in the 1970s, few would have predicted the heights to which bottled water would eventually climb. Where once it would have been unimaginable to see Americans walking down the street carrying plastic bottles of water, or driving around with them in their cars’ cup holders, now that’s the norm."

However, some critics question if the apparently healthy adjustment is as positive as it seems.

"Bottled water is the marketing trick of the century," John Jewell wrote in The Week in 2014.

Companies selling bottled water, he argues, have managed to convince people that buying water is a healthier choice than sugary soda.

But the truth is, the comparison is a case of false equivalence. Bottled water isn’t simply an alternative to soda — it’s an alternative to tap water, which is free and much more eco-friendly. By buying bottled water, consumers aim to establish themselves as savvy and health-conscious, even though they could simply drink a glass of tap water that is 2,000 times less expensive.

While bottled water is often marketed as the better, safer option, companies do not have to share the same basic information that all tapped water suppliers do. In a 2008 study, the Environmental Working Group found 38 pollutants in 10 brands of bottled water. Two of the 10 brands tested were chemically indistinguishably from local tap water.

However, bottled waters sales will likely only continue to grow in the coming years. PepsiCo and Coca-Cola are seriously investing in bottled water brands. Pepsi even bought a 30-second Super Bowl ad to debut the company's new premium bottled water brand, "LIFEWTR."

Right now bottled water is bigger than soda — and beverage giants aren't going to miss out on sales.