For the first time since Prohibition, the Adolph Coors Company is selling a nonalcoholic beverage. The new product is called Coors Rocky Mountain Sparkling Water.

The product will go on sale this week in Colorado, Arizona and Northern California - mainly in the San Francisco area.

''Bottled water is the fastest-growing beverage category in America,'' John Recca, the company's brand development manager, said.

Coors Rocky Mountain Sparkling Water will be packaged in six-packs containing 6.5-ounce bottles as well as in 28-ounce bottles, the company said. It will also be available in lemon-lime and cherry flavors.