The Metropolitan Water District of Southern California will begin adding the cavity-fighting agent fluoride to the drinking water for 18 million Southern Californians starting today.
The MWD said it will supplement the trace amounts of naturally occurring fluoride in the water it imports from the Colorado River and Northern California to levels promoted by the American Dental Association and national public health groups.
According to the MWD, a cooperative of 26 cities and water agencies serving 18 million people in six counties, 43 of the largest 50 cities in the United States fluoridate drinking waters.
The level of fluoride will rise from the current range of 0.1 to 0.4 parts per million to the recommended range of 0.7 to 0.8 part per million, according to Metropolitan.
Some of the cities and water agencies may blend Metropolitan water with their own supply, so the level of fluoride may differ from area to area, according to MWD officials. They noted that fluoride levels in drinking water are limited under California state regulations at a maximum level of 2 parts per million.
The water will taste the same, according to the MWD.
“It will not be discernable,” said MWD spokesman Rob Hallwachs.
The fluoridation will begin today at the district’s Henry J. Mills Water Treatment Plant in Riverside, which provides water to southwest Riverside County, and continue to the district’s four other plants over a six-week period.
The remaining schedule is as follows:
— Nov. 12 at the F.E. Weymouth plant in La Verne, which serves Los Angeles County;
— Nov. 19, at the Robert B. Diemer plant in Yorba Linda, which serves Orange County;
— Nov. 26 at the Joseph P. Jensen plant it Granada Hills, serving Los Angeles and Ventura counties; and
— Dec. 3 at the Robert A. Skinner plant, which serves southwest Riverside and San Diego counties.