Alkaline water is water with a higher pH than tap water. Seven is pH neutral. The higher the pH level, the more BPA free water or alkaline it is.The lower the pH, the more acidic it is.Tap water has a pH of about 7 and alkaline water about 8 or 9,”says Malina Malkani, nutritionist and spokesperson for the Academy of Nutrition and Dietetics. "Alkaline compounds are salts and metals that, when added to water, make it more basic.