Charleston water at a glance
- Water utility
- Charleston Water System
- Hardness
- 58.4 ppm (about 3.4 grains per gallon), described as moderately soft (Charleston Water System)
- Disinfection
- Chlorine dioxide and chloramines (Charleston Water System)
- Private wells
- Found in outlying parts of Charleston, Berkeley and Dorchester counties
Which utility serves your home?
Around Charleston, water comes from several utilities:
- Charleston Water System serves the City of Charleston and much of the surrounding area.
- Mount Pleasant Waterworks serves Mount Pleasant.
- Summerville CPW serves Summerville.
- Berkeley County Water & Sanitation serves parts of Berkeley County.
Check your water bill to see which one serves you. Each publishes its own annual water quality report, and our test measures what actually reaches your tap.
Where Charleston's city water comes from
- SourceBushy Park Reservoir (about 90%) and the Edisto River (about 10%)
- TreatmentHanahan Water Treatment Plant
- DisinfectionChlorine dioxide and chloramines
- Your tapThen your own pipes and water heater, which our free test checks
Drinking water in Charleston
Charleston Water System treats and monitors its water under federal and state rules and publishes an annual water quality report. RO is an extra barrier some households add for drinking and cooking, particularly in older homes, where lead can come from household plumbing rather than the utility's mains.
PFAS and Charleston water
The EPA set the first national drinking water limits for several PFAS in 2024, and utilities publish their monitoring in annual water quality reports. Check Charleston Water System's latest report for your area; RO adds a second barrier at your kitchen tap.
What reverse osmosis reduces
Certified systems reduce dissolved solids, lead, many PFAS compounds, nitrates and arsenic, and their carbon stages take out chlorine or chloramine taste. Look for certification to NSF/ANSI 58 for the contaminants you care about. How reverse osmosis works.
What happens at your free test
Your free test measures hardness, chlorine or chloramine, iron, pH and total dissolved solids at your tap, and you keep the written report. We recommend a reverse osmosis system only if your results call for it. How the free test works.
Where we work around Charleston
We test homes across Charleston, West Ashley, James Island, Mount Pleasant, Summerville and Goose Creek.
Sources
- Charleston Water System: how hard is Charleston's water?
- Charleston Water System: how is the water disinfected?
- SCDES: well water quality testing services
Frequently asked questions
Do older Charleston homes need a reverse osmosis system?
Not automatically, but homes built before 1986 can have lead solder or fixtures. Testing shows whether lead is a concern at your tap, and a certified RO system reduces it.
Does reverse osmosis remove PFAS?
Reverse osmosis is one of the most effective home treatments for PFAS. Certified systems list which PFAS they were tested to reduce.
Where does the system go?
Under the kitchen sink, with its own faucet. It can also feed a refrigerator or ice maker.