Is Twin Rocks, PA Tap Water Safe to Drink?
Graded D+ — but Lead was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
52/100
waterverge.com Twin Rocks, PA — Water Quality Report
Twin Rocks's drinking water received a grade of D+ (52 out of 100), indicating poor water quality. The city's 1 water system serves approximately 1,650 residents using purchased surface water.
Lead levels were measured at 17.0 ppb (90th percentile), which exceeds the EPA action level of 15 ppb. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 47 violations on record, including 24 health-based violations. 14 remain unresolved.
What to know about Twin Rocks's water
Twin Rocks ranks #312 out of 560 cities in Pennsylvania for water quality, placing it below 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.
Lead levels exceed the EPA action level of 15 ppb, which typically indicates aging lead service lines or lead solder in the distribution system. An NSF 53-certified filter is strongly recommended for drinking and cooking water.
As a small community water system, Twin Rocks may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 6 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Twin Rocks, PA water safe to drink?
Twin Rocks's drinking water has significant quality concerns based on EPA testing data. With a grade of D+ (52/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,650 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Twin Rocks
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Twin Rocks's water quality assessment. Grade: D+ (52/100).
Contaminants: Public Notice.
Contaminants: Public Notice.
1 health-based. Contaminants: Surface Water Treatment Rule.
Federal disaster declaration (FEMA DR-3356). Hurricane event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3340). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Twin Rocks's water supply.
Exceeds EPA action level. Lead service line replacement and point-of-use filtration recommended.
Violation history
Twin Rocks's water system has 47 total violations on record, including 24 health-based violations. 14 remain unresolved. 6 violations were issued in the last 5 years.
Flood & environmental risk
Cambria County has experienced 8 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. Local water sources include Little Conemaugh River At Wilmore.
Where does Twin Rocks's water come from?
Twin Rocks's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 1,650 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Little Conemaugh River At Wilmore (river).
What Twin Rocks residents can do
Recommended: NSF 53-certified pitcher or under-sink filter. This addresses the specific contaminants found in Twin Rocks'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.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Twin Rocks'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 Twin Rocks
Industrial polluters nearby
Reported releases to surface water by facilities near Twin Rocks, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
COLVER GREEN ENERGY COLVER, PA15927 | — | — | 4.6 mi |
EBENSBURG POWER CO EBENSBURG, PA15931 | — | — | 6.5 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Cambria County has experienced 8 federally declared disasters since 1972. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Twin Rocks'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. | 17.0 | 15 | ppb | Inorganic | Over Limit |
Lead level trend (90th percentile)
See how Twin Rocks compares by contaminant
Explore where Twin Rocks ranks among all Pennsylvania cities for specific contaminants.
Water source & infrastructure
Where Twin Rocks's water comes from
Twin Rocks's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
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 1,650 people through 1 water system.
Water bodies near Twin Rocks
Twin Rocks is located near 1 notable water body. As a surface water system, these water bodies may directly influence the city's drinking water supply.
Water systems serving Twin Rocks
| System Name | PWSID | Population | Source |
|---|---|---|---|
| BLACKLICK VALLEY MUNI AUTH | PA4110077 | 1,650 | SWP |
How Twin Rocks compares
Full Pennsylvania rankings →Twin Rocks's score of 52/100 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 →Learn more about your water
Guides and resources related to Twin Rocks's water quality findings.
Explore water quality across Cambria
Frequently asked questions
Is Twin Rocks, PA tap water safe to drink?
Twin Rocks's water quality earned a grade of D+ (52/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #312 out of 560 cities tested in Pennsylvania.
What contaminants are in Twin Rocks's water?
Lead was measured at 17.0 ppb (90th percentile). 47 violations are on record.
How is Twin Rocks'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 Twin Rocks?
Yes — lead levels exceed the EPA action level of 15 ppb. We recommend an NSF 53-certified filter or reverse osmosis system. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Twin Rocks's water come from?
Twin Rocks's water is sourced from Purchased surface water. The city has 1 water system serving approximately 1,650 residents.
What health violations has Twin Rocks's water system had?
Twin Rocks has 24 health-based violations on record. The most recent violation was recorded in November 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 14 violations remain unresolved.
How does Twin Rocks's water compare to other cities?
Twin Rocks ranks #312 out of 560 cities in Pennsylvania (better than 44% of state cities) and #12817 out of 15744 cities nationally (19th percentile). The grade of D+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Twin Rocks's small water system affect quality?
Twin Rocks's system serves approximately 1,650 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 47 violations on record.