According to the US Environmental Protection Agency, normal drinking water should have a pH level between 6.5 and 8.5. Drinking water must have a pH value of 6.5-8.5 to fall within EPA standards. They further note that even within the acceptable pH range, slightly high- or low-pH water can be unappealing for several reasons.
High-pH water has a slippery feel, tastes a bit like baking soda, and may leave deposits on fixtures, according to the EPA website. Low-pH water, on the other hand, may have a bitter or metallic taste, and may contribute to fixture corrosion