Fluoridation by Public Water Systems

Is My Water Supply Fluoridated?

Please visit the CDC’s My Water’s Fluoride page to see if your water system provides fluoridated drinking water.  For more detailed information about your water system’s fluoride level, please contact your water system and request a copy of their most recent Consumer Confidence Report or Water Quality Report.

2016 Fluoridation Data

Additional Historic Fluoridation Data

Fluoridation - April 2015 Revision to Optimal Fluoride Level

The U.S. Department of Health and Human Services Agency (HHS) is recommending that water systems practicing fluoridation adjust their fluoride content to 0.7 mg/L (parts per million), as opposed to the previous temperature-dependent optimal levels ranging from 0.7 mg/L to 1.2 mg/L. There is no change regarding federal health officials' strong and long-standing support regarding the value of fluoridation of drinking water.

Detailed information on the basis for this change is available via the Centers for Disease Control and Prevention's (CDC's) website. The change in the optimal level is a result of recent scientific evidence in four areas on the subject:

  1. The effectiveness of fluoridation on dental caries prevention and control for all age groups.
  2. The availability of fluoride through other sources
  3. Trends in the prevalence and severity of dental fluorosis
  4. Fluid intake by children across various ambient air temperatures.

This optimal target goal is aimed at providing the benefits of fluoridation while minimizing the chance that children develop dental fluorosis, a typically mild condition that causes a discoloration of teeth.

To reflect CDC’s recommendation, DDW will be consulting with public water systems practicing fluoridation regarding amendments to their individual public water supply permits to reference the CDC's recommended optimal level of 0.7 mg/L. The recommended optimal level of 0.7 mg/L currently corresponds with the existing California Water Fluoridation Standards control range of 0.6 mg/L to 1.2 mg/L. Public water systems are advised of the following:

  • Public water systems practicing fluoridation are advised that they may immediately implement the CDC’s recommended optimal level of 0.7 mg/L and control range of 0.6 ppm to 1.2 ppm.
  • DDW District Offices will issue a letter to each public water system practicing fluoridation by the end of May 2015 and initiate the water supply permit amendment process soon after.
  • DDW will be developing amendments to the California Code of Regulations to incorporate the new CDC recommendation.

Water system practicing fluoridation may contact the local DDW District Office with questions regarding the addition of fluoride to the water supply or the maintenance of optimum fluoride concentrations in the water delivered to customers.

Tooth decay is the number one chronic condition for children. It may result in pain, poor nutrition, and dysfunctional speech, as well as a lack of concentration, poor appearance, low self-esteem and absenteeism. Optimally fluoridated water is the single most cost-effective strategy that a community can take to improve the oral health of its residents. Studies consistently show that water fluoridation reduces tooth decay by 20 to 40 percent. The recommendations of HHS resulted from an updated review of the various current sources of fluoride, including water fluoridation. Providing the optimal level of fluoride protects the dental health of people of all ages, not just children.

DDW is responsible for regulating the activities of fluoridating public water systems in California. This responsibility includes assuring water fluoridation is conducted in a safe and effective manner. Public water systems must obtain a permit from DDW to fluoridate their drinking water supplies and must monitor the fluoride levels in their water system on a daily basis. The operational and monitoring information is also reported to DDW. For copies of the reporting requirements and reporting forms, click on the links below.

Fluoridation and Infant Formula

Concerns have been raised about the use of fluoridated drinking water in infant formula. For more information on this topic, click on the links below.

Fluoridation Management

The fluoridation of public water systems in California by two of its organizations:

  • DDW provides technical and engineering expertise to public water systems for permitting and operating fluoridation systems. DDW is the regulatory agency and responsible for assuring fluoridation systems are optimally fluoridating the water supplies to provide dental health benefits.
  • The Office of Oral Health (OOH) within the Chronic Disease Control Branch, provides scientific, technical, and health related expertise to communities interested in fluoridating their drinking water supplies. OOH is also responsible for securing funds to purchase and install fluoridation equipment for public water systems.

Fluoridation Monitoring and Reporting

Reporting Requirements and Reporting Forms

Required Reporting
Where there are two, choose the correct report form to use
Monthly Distribution Monitoring
Year-to-Date Distribution Summary
Monthly Treatment Summary
Yearly Treatment Summary
Optimal Fluoride Control Range
Calculation (Done Annually)
Annual Cost Summary
Voluntary Fluoridation (Only for
systems that purchase fluoridated
water but do not supplement with
additional fluoride)