Cal. Health & Safety Code § 111185

Any bottler, distributor, vendor of bottled water, or owner or operator of any water-vending machine or retail water facility, whose corporate name or trademark contains the words “spring” or “springs,” or any derivative of either of these words, or “well,” “artesian well,” or “natural” shall label each bottle or vending machine with the source of the water in typeface at least equal to the size of the typeface of the corporate name or trademark, if the source of the bottled or vended water is different from the source stated in the corporate name or trademark. Retail water facilities that do not provide labeled containers shall post, in a location readily visible to consumers, a sign conveying required label information.