Is Mercer, PA Tap Water Safe to Drink?
Graded D, with 44 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
49/100
waterverge.com Mercer, PA — Water Quality Report
Mercer's drinking water received a grade of D (49 out of 100), indicating poor water quality. The city's 3 water systems serve approximately 2,621 residents using groundwater.
Lead levels were measured at 1.0 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 544 violations on record, including 3 health-based violations. 44 remain unresolved.
What to know about Mercer's water
Mercer ranks #335 out of 560 cities in Pennsylvania for water quality, placing it below average in the state.
Mercer 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, Mercer may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 94 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Mercer, PA water safe to drink?
Mercer's drinking water has significant quality concerns based on EPA testing data. With a grade of D (49/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 2,621 residents using groundwater (wells).
Recent water quality updates for Mercer
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Mercer's water quality assessment. Grade: D (49/100).
Contaminants: Revised Total Coliform Rule.
1 health-based. Contaminants: Groundwater Rule.
Contaminants: Revised Total Coliform Rule.
Federal disaster declaration (FEMA DR-3356). Hurricane event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3235). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Mercer's water supply.
Well within EPA limits.
Violation history
Mercer's water system has 544 total violations on record, including 3 health-based violations. 44 remain unresolved. 94 violations were issued in the last 5 years.
Flood & environmental risk
Mercer County has experienced 6 federally declared disasters since 1972. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.
Where does Mercer's water come from?
Mercer's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 2,621 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Mercer residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Mercer'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.
Mercer's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Mercer
Industrial polluters nearby
Reported releases to surface water by facilities near Mercer, ranked by pounds discharged annually.
Total reported releases to surface water: 112,713 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
DAIRY FARMERS OF AMERICA INC NEW WILMINGTON, PA16142 | Nitrate compounds (water dissociable; reportable only when in aqueous solution) | 112,713 | 9.8 mi |
OLDCASTLE APG - FREDONIA FREDONIA, PA16124 | — | — | 6.7 mi |
WABTEC US RAIL INC GROVE CITY, PA16127 | — | — | 7.8 mi |
PINE INSTRUMENT CO GROVE CITY, PA16127 | — | — | 7.9 mi |
GE TRANSPORTATION GROVE CITY UX PLANT GROVE CITY, PA16127 | — | — | 9.7 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Mercer County has experienced 6 federally declared disasters since 1972. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
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. | 1.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Mercer compares by contaminant
Explore where Mercer ranks among all Pennsylvania cities for specific contaminants.
Water source & infrastructure
Where Mercer's water comes from
Mercer'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 private ownership and serves approximately 2,621 people through 3 water systems.
Water systems serving Mercer
| System Name | PWSID | Population | Source |
|---|---|---|---|
| BUHL COMMUNITY WATER COMPANY | PA6430049 | 2,227 | GW |
| PINE GROVE MOBILE HOME PARK | PA6430046 | 244 | GW |
| GREENVILLE MHP | PA6430039 | 150 | GW |
How Mercer compares
Full Pennsylvania rankings →Mercer's score of 49/100 is on par with the average of 49/100 among major Pennsylvania cities. It outscores 8 of 10 nearby cities.
Nearby cities
View Pennsylvania rankings →About Mercer, PA
Learn more about your water
Guides and resources related to Mercer's water quality findings.
Explore water quality across Mercer
Frequently asked questions
Is Mercer, PA tap water safe to drink?
Mercer's water quality earned a grade of D (49/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #335 out of 560 cities tested in Pennsylvania.
What contaminants are in Mercer's water?
Lead was measured at 1.0 ppb (90th percentile). 544 violations are on record.
How is Mercer'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 Mercer?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Mercer's water come from?
Mercer's water is sourced from Groundwater. The city has 3 water systems serving approximately 2,621 residents.
What health violations has Mercer's water system had?
Mercer has 3 health-based violations on record. The most recent violation was recorded in August 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 44 violations remain unresolved.
Is Mercer's groundwater at risk of contamination?
Mercer 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 544 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 Mercer's water compare to other cities?
Mercer ranks #335 out of 560 cities in Pennsylvania (better than 40% of state cities) and #13336 out of 15744 cities nationally (15th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.