We treat water from the Edisto River and the Bushy Park Reservoir, both of which are surface water sources. The water is treated at our Hanahan Water Treatment Plant, which is permitted to treat up to 115.4 million gallons per day (mgd).
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No, we are fortunate to have an abundant water supply, even during a drought.
Yes, our source water includes naturally occurring fluoride (approximately 0.15 mg/L), and we adjust the level to approximately 0.7 mg/L during the treatment process.
Drinking Water Fluoridation (Position Statement)Adopted by the Board of Commissioners October 24, 2017The Charleston Water System (CWS) supports the recommendations of the World Health Organization, American Medical Association, Canadian Medical Association, Centers for Disease Control and Prevention (CDC), American Dental Association, Canadian Dental Association, South Carolina Dental Association and other professional organizations in the medical community, for the proper fluoridation of public water supplies as a public health benefit. We also support regular scrutiny of the most current peer reviewed research on fluoride and the positions of the medical and dental community.We adjust the naturally occurring level of fluoride in our drinking water in a responsible, effective, and reliable manner that includes monitoring and controlling fluoride levels as mandated by state and/or federal laws, regulations and recommendations. We carefully monitor and adjust potable water to achieve the scientifically recommended concentration of fluoride for protection against dental caries, which is 0.7 parts per million. Our annual cost for this program is about $110,000, which equates to $0.25 per person across the approximately 450,000 people in our water service area.The CWS participates in the fluoridation of water under the guidance of the South Carolina Department of Health and Environmental Control (SCDHEC), Oral Health Division. SCDHEC coordinates their program in conjunction with the CDC and the U.S. Department of Health and Human Services.If there are questions regarding these programs, please contact:SCDHECDivision of Oral Health2100 Bull Street, Columbia, S.C. 29201P: (803) 898-9577F: (803) 898-2065
We use chlorine dioxide and chloramines (a compound formed by combining ammonia and chlorine) to protect against harmful microorganisms.
Chloramines are more stable than chlorine in the water distribution system, and chloramine residuals help maintain consistent water quality. The amount of disinfectant is carefully measured to the lowest level needed to keep the water free of disease-causing organisms. Learn more about the water treatment process.
Charleston Water System prevents the corrosion of lead plumbing into water by adjusting the properties of our water. We add a corrosion inhibitor during the treatment process, which forms a molecular barrier between the pipe and the water inside.
The results of our lead testing are well below the USEPA’s limit of 15 parts per billion (ppb). Lead testing results are included in our most recent water quality report.
As an extra precaution, customers can minimize the potential for lead exposure by flushing out water that has been sitting in your home’s plumbing for several hours or more. Just let your water run for up to two minutes before using it for cooking or drinking.
Charleston Water System offers free lead tests. Testing kits are available at our office locations: 103 St. Philip St., Downtown, and 6296 Rivers Ave., North Area.
No. We use chloramines (a combination of chlorine and ammonia) to disinfect drinking water which are harmful to fish and other aquatic life. There are a number of products available at pet stores to remove chloramines from your fish tank.
Our tap water is safe for dog, cats, and other non-aquatic pets.
If the public water system becomes contaminated or a situation allows the possibility of contamination (such as a water main break or loss of system pressure), we will issue a Boil Water Advisory.
The SC Department of Health and Environmental Control (SCDHEC) requires the issuance of a Boil Water Advisory under certain conditions, such as widespread loss of system pressure or a large water main break.
If an advisory is issued, we will notify customers in a variety of ways, depending on the area affected. During an advisory, customers should bring water to a vigorous boil for at least one minute and let it cool before using for cooking or drinking. This will kill any bacteria that may be in the water.