Bottled water has been enjoying growth for years, while sales of traditional sodas have declined. Research and consulting firm Beverage Marketing Corp. says Americans drank an average of 39.3 gallons of bottled water in 2016, and 38.5 gallons of carbonated soft drinks. In 2015, bottled water was at 36.5 gallons while soda was at 39 gallons.

Other industry trackers define categories differently, so may see the cross at different times. Beverage Marketing includes sparkling waters in bottled waters and excludes energy drinks in sodas. Another tracker, Beverage Digest, says by its metrics bottled water will surpass soda this year.

The estimates don't include tap water.