A unanimous vote by the San Diego City Council last June authorized initiating fluoride into the city's water supply. San Diego was, to this point, the largest non-fluoridated city in the United States. The project should be completed by 2010 in its three water treatment plants. California Dental Association (CDA) Foundation Executive Director Jon Roth expressed his thanks that the long journey to get San Diego fluoridated had been completed. The San Diego City Council also selected the CDA Foundation to manage the implementation of the community water fluoridation program at a cost of $3.9 million to serve the some million area residents.

In 2007, the Metropolitan Water District of Southern California began fluoridation to its 18 million customers, which includes 9% of San Diego. This was the single largest expansion of fluoridation in the United States.