Pure Water First’s purification systems are an excellent alternative to traditional bottled jugs as well as bottleless water coolers. Our state of the art filtration systems transforms your tap water through a four stage reverse osmosis process into pure, clean, refreshing drinking water. The Nine (9) Bay Area counties that we serve are Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Solano and Sonoma.