Who serves this area
Most of the Town of Summerville is served by the Commissioners of Public Works of the Town of Summerville (Summerville CPW), public water system ID SC1810003. Some nearby neighborhoods, especially in Berkeley County, may instead be served by Berkeley County Water & Sanitation or another utility. Check your water bill if you are unsure.
The current report is the Annual Water Quality Report — Reporting Year 2025, covering January 1–December 31, 2025, at summervillecpw.com/waterqualityreport.
Where the water comes from and how it is treated
The source is Lake Moultrie, a 60,000-acre reservoir in the Catawba-Santee basin. Water is treated at the Santee Cooper Regional Water System's Lake Moultrie plant (about 40 million gallons a day, operating since 1994) and then sent to Summerville CPW, which maintains about 390 miles of distribution pipe. The same regional plant also supplies the City of Goose Creek, Moncks Corner, and Berkeley County Water & Sanitation. The plant participates in the Partnership for Safe Water. Finished water is disinfected, and chloramines are used to help limit disinfection byproducts in the pipes. Fluoride is present in the treated water from the plant (0.64 ppm in 2025).
Sources: Summerville CPW 2025 report (PDF).pdf).
How to read these numbers
Utilities must meet a legal limit — usually a Maximum Contaminant Level (MCL), a Maximum Residual Disinfectant Level (MRDL) for disinfectants, or an Action Level (AL) for lead and copper. The health goal, or Maximum Contaminant Level Goal (MCLG), is the level below which EPA expects no known health risk. It is often lower than the legal limit, and it is not a violation if a result is above the health goal but below the legal limit.
PFAS figures below are compared with EPA's current legal limits of 4 parts per trillion (ppt) for PFOA and PFOS, and 10 ppt for PFHxS, PFNA, and HFPO-DA (GenX). Those limits were finalized in 2024. They are not yet being enforced as violations. The original compliance deadline is 2029; EPA has since discussed extending it to 2031. Until a later deadline is finalized, treat 2029 as the date utilities have been told to plan for.
Sources: EPA PFAS drinking water rule; EPA announcement on PFOA and PFOS MCLs; Charleston Water System 2026 Water Quality Report, p. 14.
What's in Summerville water
Summerville CPW reported that the water met all federal and state requirements in 2025, with no violations. Where the report lists both the Summerville distribution system and the Lake Moultrie plant, the table uses the figure that applies to Summerville customers when one is given, and the plant figure when the substance was measured only there.
| Substance | Level | Legal limit | Health goal (MCLG) | Year | Notes |
|---|---|---|---|---|---|
| Chlorine (distribution) | 3.8 ppm (range 1.2–3.8) | 4 ppm MRDL | 4 ppm MRDLG | 2025 | Water additive used to control microbes. |
| Chloramines (plant) | 3.27 ppm (range 3.10–3.27) | 4 ppm MRDL | 4 ppm MRDLG | 2025 | Measured at the Lake Moultrie plant. |
| Fluoride (plant) | 0.64 ppm | 4 ppm | 4 ppm | 2025 | |
| Nitrate (plant, as nitrogen) | 0.28 ppm | 10 ppm | 10 ppm | 2025 | |
| Selenium (plant) | 4.3 ppb | 50 ppb | 50 ppb | 2025 | |
| Haloacetic acids (HAA5) | Running annual average 15 ppb (range 11–17) | 60 ppb | None set | 2025 | Disinfection byproduct in the Summerville system. |
| Total trihalomethanes (TTHM) | Running annual average 30 ppb (range 13–36) | 80 ppb | None set | 2025 | Disinfection byproduct in the Summerville system. |
| Turbidity (plant) | Highest 0.18 NTU (range 0.06–0.18); 100% of samples met the limit | Treatment technique (95% under 0.3 NTU) | — | 2025 | |
| Total organic carbon (plant) | 1.35 (running annual average removal ratio); range 1.2–2.5 ppm | Treatment technique | — | 2025 | |
| Gross alpha, excluding radon and uranium (plant) | 1.02 pCi/L | 15 pCi/L | 0 pCi/L | 2022 | |
| Copper (90th percentile at customer taps) | 0.065 ppm (range 0.002–0.120); 0 of 30 sites over the action level | 1.3 ppm action level | 1.3 ppm | 2023 | |
| Lead (90th percentile at customer taps) | 0.9 ppb (range not detected–7); 0 of 30 sites over the action level | 15 ppb action level | 0 ppb | 2023 | See the lead section. |
| pH (distribution / plant) | 7.5 in the system (range 6.5–8.5); 7.93 at the plant (range 7.8–8.0) | 6.5–8.5 secondary guideline | — | 2025 | Aesthetic guideline, not a health-based MCL. |
| Total dissolved solids (plant) | 72.5 ppm | 500 ppm secondary guideline | — | 2025 | |
| Hardness, total as CaCO3 (plant) | 23 ppm | No standard | — | 2025 | Soft water. |
| Sodium (plant) | 10 ppm | No MCL | — | 2025 | |
| PFOA (Summerville system, UCMR 5) | 5.7 ppt (range 4.8–6.2) | 4 ppt (future standard; not a current violation) | 0 ppt | 2024–2025 | Samples from Q3–Q4 2024 and Q1–Q2 2025. |
| PFOS (Summerville system, UCMR 5) | 6.7 ppt (range 4.8–8.1) | 4 ppt (future standard; not a current violation) | 0 ppt | 2024–2025 | Same sampling window. |
| PFBS (Summerville system) | 4.0 ppt (range 3.7–4.4) | No standalone MCL | — | 2024–2025 | |
| PFHxA (Summerville system) | 5.5 ppt (range 5.2–5.9) | No MCL | — | 2024–2025 | |
| PFBA (Summerville system) | 2.6 ppt (range ND–5.1) | No MCL | — | 2024–2025 | |
| PFPeA (Summerville system) | 6.2 ppt (range 5.6–6.6) | No MCL | — | 2024–2025 | |
| PFOA (Lake Moultrie plant) | 6.7 ppt (range 5.9–7.4) | 4 ppt (future standard; not a current violation) | 0 ppt | 2025 | Plant finished water. |
| PFOS (Lake Moultrie plant) | 7.3 ppt | 4 ppt (future standard; not a current violation) | 0 ppt | 2025 | The official Summerville table lists a plant range of "7.2–2.4," which appears to be a typographical error. The City of Goose Creek 2025 report, for the same Santee Cooper plant, lists 7.2–7.4 ppt. The 7.3 ppt average is used here. |
| GenX / HFPO-DA (plant) | 3.0 ppt (range 2.8–3.1) | 10 ppt (future standard) | — | 2025 | |
| PFHxS (plant) | 2.0 ppt (range 1.9–2.1) | 10 ppt (future standard) | — | 2025 | |
| PFHpA (plant) | 2.6 ppt (range 2.5–2.6) | No MCL | — | 2025 | |
| PFBS (plant) | 3.8 ppt (range 3.7–3.8) | No standalone MCL | — | 2025 |
Source: Summerville CPW 2025 Annual Water Quality Report, test-results tables and footnotes 1–3.
Lead
Summerville CPW says that, based on maintenance records, employee interviews, an EPA-approved statistical model, and routine sampling, it can assert with a high level of confidence that no lead service lines are present in its distribution system. A map is at summervillecpw.com/serviceinfo.
Since 1994 the utility has sampled residences built before 1986. In the 2023 round (30 sites), the 90th percentile was 0.9 ppb lead and 0.065 ppm copper, with no site over the action level. The highest lead result in that round was 7 ppb. Lead can still come from a home's own plumbing. For testing options, the report lists Alicia Wilson at (843) 875-8757.
Source: Summerville CPW 2025 report, "Lead in Home Plumbing" and lead/copper table.
PFAS
The report states that Santee Cooper has found PFAS in Lake Moultrie source and treated water at levels slightly higher than the new EPA standards, and that Santee Cooper is evaluating treatment so it will be ready when those standards take effect.
In Summerville's own UCMR 5 results (late 2024 through mid-2025), average PFOA was 5.7 ppt and average PFOS was 6.7 ppt — above the future 4 ppt standard, and not a current violation. The plant averages were 6.7 ppt PFOA and 7.3 ppt PFOS. GenX at the plant averaged 3.0 ppt, below the future 10 ppt standard.
Source: Summerville CPW 2025 report, PFAS narrative and unregulated-substances table.
Disinfection byproducts
In the Summerville distribution system in 2025, the running annual average was 30 ppb TTHM (limit 80) and 15 ppb HAA5 (limit 60). Individual TTHM results ranged up to 36 ppb. The report notes that chloramines are used as a secondary disinfectant to help keep these byproducts down.
Source: Summerville CPW 2025 report, regulated-substances table.
What the utility report can't tell you
A utility report describes water as it leaves the treatment plant and as it moves through the public system. It cannot tell you what comes out of your own faucet.
- Your pipes and fixtures. Lead and copper usually come from a home's service line, solder, or fixtures — especially in homes built before the 1986 federal lead ban — not from the water leaving the plant.
- Private wells. If you are on a well, this report does not apply to you. South Carolina does not regulate private household wells; owners are responsible for testing.
- Older homes. Even when a utility meets every legal limit, a single older home can still have higher lead or copper at the tap.
A useful next step
If you want a snapshot of your own tap water, Auraven Labs offers a free in-home water check. During the visit we measure pH, conductivity, TDS (total dissolved solids), and salinity. Those readings do not detect lead, bacteria, PFAS, or other contaminants, and they do not determine whether your water is safe.
If you want a certified laboratory analysis of your tap water, the City Basic lab test is available for $329.