The FDA has established a Standard of Identity to define different types of bottled water based on specific characteristics of the product. Bottled water products meeting the Standard of Identity may be labeled as bottled water or drinking water, or one or more of the following terms:

Artesian Water/Artesian Well Water: Bottled water from a well that taps a confined aquifer (a water-bearing underground layer of rock or sand) in which the water level stands at some height above the top of the aquifer.

Mineral Water: bottled water containing not less than 250 parts per million total dissolved solids may be labeled as mineral water. Mineral water is distinguished from other types of bottled water by its constant level and relative proportions of mineral and trace elements at the point of emergence from the source. No minerals can be added to this product.

Purified Water: Bottled water produced by distillation, deionization, reverse osmosis, or other suitable process and that meets the definition of purified water in the most recent addition of the United States Pharmacopeia.

Sparkling Bottled Water: Water that after treatment, and possible replacement with carbon dioxide, contains the same amount of carbon dioxide that it had as it emerged from the source. Sparkling bottled waters may be labeled as "sparkling drinking water, "sparkling mineral water, "sparkling spring water," etc.

Well Water: Bottled water from a hole bored, drilled, or otherwise constructed in the ground, which taps the water aquifer.

Spring Water: Water derived from an underground formation from which the water flows naturally to the surface of the earth. Spring water shall be collected only at the spring or through a borehole tapping the underground formation feeding the spring. There shall be a natural force causing the water to flow to the surface through a natural orifice. The location of the spring shall be identified and such identification shall be maintained in the company's records. Spring water collected with the use of an external force shall be from the same underground striation as the spring, as shown by a measurable hydraulic connection using a hydro geologically valid method between the borehole and the natural spring, and shall have all the physical properties, before treatment, and be of the same composition and quality as the water that flows naturally to the surface of the earth. If spring water is collected with the use of an external source, water must continue to flow naturally to the surface of the earth through the spring's natural orifice. Plants shall demonstrate, on request, to appropriate regulatory officials using a hydro geologically valid method that an appropriate hydraulic connection exists between the natural orifice of the spring and the borehole.

Information provided by the International Bottled Water Association.