Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that the water poses a health risk. You can learn more about contaminants and potential health effects by calling the U.S. Environmental Protection Agency’s (USEPA) Safe Drinking Water Hotline at 800-426-4791 or visiting the website at epa.gov/safewater.
To ensure that tap water is safe to drink, the USEPA prescribes regulations, which limit the amount of certain contaminants in water provided by public water systems. Food and Drug Administration (FDA) regulations establish limits for contaminants in bottled water. Both sets of requirements protect public health.
Some people may be more vulnerable to contaminants in drinking water than the general population. Immunocompromised persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers.
Fluoride. The City of Santa Ana receives approximately 28 percent of its water supply from MWD. Beginning in October 2007, MWD joined a majority of the nation’s public water suppliers in adding fluoride to the treated water it supplies to state water agencies, a plan approved by the CDC and the State Water Resources Control Board (SWRCB)1. Santa Ana’s well water has a naturally occurring fluoride range level of 0.18 to 0.56 ppm. Water provided by MWD has been adjusted to the optimal range for dental health of 0.7 to 0.8 parts per million. Additional information may be found by calling MWD’s Water Quality Information Hotline at 800-354-4420. You can also download a fact sheet at mwdh2o.com/fluoridation/fluoridationfactsheet.pdf or visit ada.org/fluoride.aspx.
Cryptosporidium. Cryptosporidium is a microbial pathogen found in surface water throughout the U.S. To date, cryptosporidium has not been detected in our water supply. USEPA/CDC (U.S. Centers for Disease Control and Prevention) guidelines on appropriate means to lessen the risk of infection by cryptosporidium and other microbial contaminants are available from the Safe Drinking Water Hotline at 800-426-4791. As of July 1, 2014, the State’s Drinking Water Program has been transferred from the California Department of Public Health (CDPH) to the State Water Resources Control Board’s Division of Drinking Water, which was created to consolidate all major water quality programs within a single department. For more information, visit swrcb.ca.gov/drinking_water/programs.
Hexavalent Chromium. In July 2014, California became the first state in the nation to regulate hexavalent chromium, also known as Chrome-6. Previously, chrome-6 had been regulated as total chromium, which includes other forms of the mineral. Chrome-6 can be present in water due to natural geologic conditions or from industrial pollution. In Orange County, groundwater often contains trace amounts of naturally occurring Chrome-6 that are far below the new MCL. See the water quality table in this report for information on Santa Ana’s water.