On April 27, 2015, the U.S. Public Health Service (PHS) published a recommendation that the optimal dosage for fluoride in water is 0.7 parts per million (ppm). Previously, the recommended dosage was expressed as a range from 0.7 to 1.2 ppm. PHS concludes that fluoridation at 0.7 ppm provides all the benefits for dental health with virtually no other health risks. High levels of fluoride can lead to fluorosis, a white mottling of tooth enamel.
Anaheim does not add fluoride to its water supply, but the Metropolitan Water District of Southern California (MWD) has been adding fluoride at its five water treatment plants since October 2007.
MWD treated water typically provides about 15% of Anaheim’s total water supply. MWD water is received at seven interconnection points in Anaheim, with the amount of water delivered dependent on consumer demand and the availability of Anaheim’s other supplies. Most of Anaheim’s customers receive some MWD treated water, but most of their water comes from Anaheim’s other sources.
MWD chose to fluoridate because it was requested by the County Health Officers of the six counties where MWD provides water. It is the position of the County Health Officers, the Centers for Disease Control, the California Dental Association, the State of California, and several other health organizations, that fluoride, in the proper dosage is a benefit to dental health.
MWD adjusts the naturally occurring fluoride level in their water, which ranges from 0.1 to 0.4 parts per million (ppm), to the optimal range for dental health as determined by the California State Water Resources Control Board. Anaheim’s groundwater typically contains about 0.4 ppm of naturally occurring fluoride, but there are no plans to add fluoride.
More information is available about MWD's fluoridation project on its Web site at