01The verdict: is Sullivans Island water safe?
Sullivans Island's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (90.3/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 2,521 residents using surface water (rivers, lakes, or reservoirs).
2 unresolved violations on record
EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.
See what was cited ↓Lead is well under the limit
90th-percentile lead is 0.6 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓Check back after the next refresh
EPA data updates on a rolling basis; we fold in new samples and violations every month.
Get alerts ↓Sullivans Island's drinking water received a grade of A (90.3 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 2,521 residents using purchased surface water.
Lead levels were measured at 0.6 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program. The system has 5 violations on record, including 2 health-based violations. 2 remain unresolved.
Sullivans Island ranks #41 out of 195 cities in South Carolina for water quality, placing it above average in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. As a small community water system, Sullivans Island may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
02What's in Sullivans Island's water
Every contaminant flagged in Sullivans Island, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 0.6 | 15 | ppb | Inorganic | Safe |
Cities ranked by 90th-percentile lead PF PFAS in South Carolina
Cities ranked by compounds detected Cu Copper in South Carolina
Cities ranked by 90th-percentile copper
03Sullivans Island's ten-year track record
Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 5 violations on record, including 2 health-based violations. 2 remain unresolved.
All ten of the last ten years were clean — no EPA violations recorded for Sullivans Island.
▼ Down 11 ppb since 1993. Latest reading: 0.59 ppb (2024) — 4% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Sullivans Island's water comes from
Sullivans Island's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Purchased Surface Water
Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.
Wholesale supplier
Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.
1 system
1 water system, operated under local government ownership.
2,521 people
Residents served across Sullivans Island's service area.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by local government ownership and serves approximately 2,521 people through 1 water system.
| System name | PWSID | Population | Source |
|---|---|---|---|
| SULLIVANS ISLAND TOWN OF (1010003) | SC1010003 | 2,521 | Purchased Surface Water |
05Pressure on Sullivans Island's watershed
Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.
Drought
Charleston County is in D3 (extreme drought) per the U.S. Drought Monitor (week of Jul 2026). Drought can raise disinfection-byproduct levels and taste/odor issues as utilities draw from lower reservoirs.
06How Sullivans Island compares
Scores for nearby South Carolina cities on one line, with the average marked.
dashed line = South Carolina average (77/100)
Sullivans Island scores 90.3/100 — above the South Carolina average of 77/100. It outscores 7 of 10 nearby cities. Full South Carolina rankings →
92.1 / 100BCharleston, SC
82.8 / 100FColumbia, SC
37.1 / 100CConway, SC
67.5 / 100BOkatie, SC
83.8 / 100ASpartanburg, SC
91.4 / 100
Compare all cities in the county — grades, violations, and contaminant data side by side.→
07What to do at home
Steps matched to what testing actually found in Sullivans Island's water — not generic advice.
A basic carbon filter still helps
Sullivans Island's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.
Compare tested filters →Read your utility's annual report
Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.
How to read a CCR →Watch for Sullivans Island alerts
We refresh EPA data monthly and surface new violations, advisories, and boil-water notices for your county on this page.
All water alerts →Frequently asked questions
Is Sullivans Island, SC tap water safe to drink?
Sullivans Island's water quality earned a grade of A (90.3/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #41 out of 195 cities tested in South Carolina.
What contaminants are in Sullivans Island's water?
Lead was measured at 0.6 ppb (90th percentile). 5 violations are on record.
How is Sullivans Island's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Sullivans Island?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Sullivans Island's water come from?
Sullivans Island's water is sourced from Purchased surface water. The city has 1 water system serving approximately 2,521 residents.
What health violations has Sullivans Island's water system had?
Sullivans Island has 2 health-based violations on record. The most recent violation was recorded in June 1997. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.
How does Sullivans Island's water compare to other cities?
Sullivans Island ranks #41 out of 195 cities in South Carolina (better than 79% of state cities) and #2287 out of 15382 cities nationally (85th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Sullivans Island's small water system affect quality?
Sullivans Island's system serves approximately 2,521 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 5 violations on record.