Is St Henry, OH Tap Water Safe to Drink?
Graded A- — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
87.2/100
waterverge.com St Henry, OH — Water Quality Report
St Henry's drinking water received a grade of A- (87.2 out of 100), indicating good water quality. The city's 1 water system serves approximately 2,596 residents using groundwater.
Lead levels were measured at 2.6 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 26 violations on record, including 0 health-based violations. 4 remain unresolved.
What to know about St Henry's water
St Henry ranks #81 out of 511 cities in Ohio for water quality, placing it above average in the state.
St Henry relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, St Henry may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is St Henry, OH water safe to drink?
St Henry's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (87.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 2,596 residents using groundwater (wells).
Recent water quality updates for St Henry
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into St Henry's water quality assessment. Grade: A- (87.2/100).
Contaminants: Consumer Confidence Rule.
Contaminants: Consumer Confidence Rule.
Contaminants: Consumer Confidence Rule.
Federal disaster declaration (FEMA DR-3250). Hurricane event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-831). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for St Henry's water supply.
Well within EPA limits.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
St Henry's water system has 26 total violations on record, including 0 health-based violations. 4 remain unresolved. 1 violation was issued in the last 5 years.
Flood & environmental risk
Mercer County has experienced 2 federally declared disasters since 1989. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Beaver Creek Near Celina, Coldwater Creek At Coldwater, Grand Lake St Marys Near Celina.
Where does St Henry's water come from?
St Henry's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 2,596 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Beaver Creek Near Celina (river), Coldwater Creek At Coldwater (river), Grand Lake St Marys Near Celina (lake).
What St Henry residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in St Henry's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Flood & disaster history
Mercer County has experienced 2 federally declared disasters since 1989. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in St Henry's water supply, we recommend the following filter types.
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. | 2.6 | 15 | ppb | Inorganic | Safe |
| Copper (90th percentile) CopperInorganic A metal that enters drinking water mainly through corrosion of copper plumbing. Small amounts are essential for health, but excess levels are harmful. Health EffectsGastrointestinal distress (nausea, vomiting, diarrhea) at short-term high levels; liver and kidney damage from long-term exposure. EPA Limit1.3 mg/L action level Common SourcesCorrosion of copper household plumbing, erosion of natural deposits. | 366.00 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how St Henry compares by contaminant
Explore where St Henry ranks among all Ohio cities for specific contaminants.
Water source & infrastructure
Where St Henry's water comes from
St Henry's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by local government ownership and serves approximately 2,596 people through 1 water system.
Water bodies near St Henry
St Henry is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving St Henry
| System Name | PWSID | Population | Source |
|---|---|---|---|
| ST HENRY VILLAGE | OH5401312 | 2,596 | GW |
How St Henry compares
Full Ohio rankings →St Henry's score of 87.2/100 is above the average of 58/100 among major Ohio cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Ohio rankings →Learn more about your water
Guides and resources related to St Henry's water quality findings.
Explore water quality across Mercer
Frequently asked questions
Is St Henry, OH tap water safe to drink?
St Henry's water quality earned a grade of A- (87.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #81 out of 511 cities tested in Ohio.
What contaminants are in St Henry's water?
Lead was measured at 2.6 ppb (90th percentile). 26 violations are on record.
How is St Henry'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 St Henry?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does St Henry's water come from?
St Henry's water is sourced from Groundwater. The city has 1 water system serving approximately 2,596 residents.
Is St Henry's groundwater at risk of contamination?
St Henry uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 26 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does St Henry's water compare to other cities?
St Henry ranks #81 out of 511 cities in Ohio (better than 84% of state cities) and #4210 out of 15744 cities nationally (73th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does St Henry's small water system affect quality?
St Henry's system serves approximately 2,596 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 26 violations on record.