01The verdict: is Irmo water safe?
Based on EPA testing data, Irmo's tap water is generally safe to drink. The water system earned a grade of A (94.9/100), meeting federal drinking water standards across key contaminant categories. The city's 2 water systems serve approximately 799 residents using surface water (rivers, lakes, or reservoirs).
Nothing over a legal limit
Every contaminant measured in Irmo's water is within its EPA limit, and no violations are unresolved.
See the testing ↓Lead is well under the limit
90th-percentile lead is 0.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓2 violations in the last five years
Recent compliance history is the best predictor of future problems — the year-by-year record is below.
See the record ↓Irmo's drinking water received a grade of A (94.9 out of 100), indicating excellent water quality. The city's 2 water systems serve approximately 799 residents using purchased surface water.
Lead levels were measured at 0.0 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 6 violations on record, including 1 health-based violation. All violations have been resolved.
Irmo ranks #9 out of 195 cities in South Carolina for water quality, placing it one of the best 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, Irmo may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
02What's in Irmo's water
Every contaminant flagged in Irmo, 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. | 0.0 | 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
03Irmo'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 6 violations on record, including 1 health-based violation. All violations have been resolved.
9 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▼ Down 6.4 ppb since 1994. Latest reading: 0 ppb (2024) — 0% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Irmo's water comes from
Irmo'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.
2 systems
2 water systems, operated under private ownership.
799 people
Residents served across Irmo'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 private ownership and serves approximately 799 people through 2 water systems.
| System name | PWSID | Population | Source |
|---|---|---|---|
| BGWC RAINTREE ACRES (SC4050015) | SC4050015 | 799 | Purchased Surface Water |
| BGWC STONEGATE (SC4050014) | SC4050014 | 352 | Purchased Surface Water |
Water bodies near Irmo
As a surface-water system, these water bodies may directly influence Irmo's drinking water supply.
05Pressure on Irmo'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.
Industrial discharge
5 facilities within 10 miles reported 46k lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.
Flood & storm history
10 federal disaster declarations on record for Kershaw County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
Drought
Richland County is in D2 (severe 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 Irmo compares
Scores for nearby South Carolina cities on one line, with the average marked.
dashed line = South Carolina average (77/100)
Irmo scores 94.9/100 — above the South Carolina average of 77/100. It outscores 10 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 Irmo's water — not generic advice.
A basic carbon filter still helps
Irmo'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 Irmo alerts
This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.
All water alerts →Frequently asked questions
Is Irmo, SC tap water safe to drink?
Irmo's water quality earned a grade of A (94.9/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #9 out of 195 cities tested in South Carolina.
What contaminants are in Irmo's water?
Lead was measured at 0.0 ppb (90th percentile). 6 violations are on record.
How is Irmo'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 Irmo?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Irmo's water come from?
Irmo's water is sourced from Purchased surface water. The city has 2 water systems serving approximately 799 residents.
What health violations has Irmo's water system had?
Irmo has 1 health-based violation on record. The most recent violation was recorded in June 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. All health violations have been resolved.
How does Irmo's water compare to other cities?
Irmo ranks #9 out of 195 cities in South Carolina (better than 95% of state cities) and #404 out of 15382 cities nationally (97th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.