F0/100
Twin Rocks Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 1,650 residents · Pennsylvania
What's In Twin Rocks's Tap Water?
4
Contaminants Tested
1
Exceed EPA Limits
0
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.017 mg/L | 0.015 mg/L | Over Limit |
EPA Violation History
4
Violations (last 5yr)
0
Unresolved
1
Health-Related
TIER 3Resolved
Disinfection byproduct treatment technique failure
When: October 11, 2025 – October 14, 2025Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 2Resolved
Failed treatment technique requirements
When: August 1, 2025 – October 15, 2025Rule: Surface Water Treatment RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Monitoring Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: October 1, 2024 – October 31, 2024Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Monitoring Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: July 1, 2023 – July 31, 2023Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
BLACKLICK VALLEY MUNI AUTH
Population Served
1,650
Water Source
Purchased Surface Water
System ID
PA4110077
Frequently Asked Questions About Twin Rocks Water
Is Twin Rocks tap water safe to drink?
Twin Rocks, Pennsylvania tap water receives a grade of F (0/100), which is considered failing. 1 contaminant(s) exceed EPA maximum contaminant levels and 46 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Twin Rocks's water?
Of the 4 contaminants tested in Twin Rocks's water supply, the most notable include Lead (90th percentile). 1 contaminant(s) exceed EPA legal limits (MCLs). 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Twin Rocks have any water quality violations?
Yes, Twin Rocks has 46 EPA violation(s) on record, with the most recent in 2025. Violation types include Other, TT, MON. 24 of these are health-based violations, which are the most serious category.
Do I need a water filter in Twin Rocks?
Based on EPA data, using a water filter in Twin Rocks is recommended. 1 contaminant(s) exceed legal limits. An NSF-certified filter — such as a reverse osmosis or activated carbon system — can effectively reduce many common contaminants. Choose a filter certified to remove the specific contaminants found in your area.
Where does Twin Rocks's tap water come from?
Twin Rocks's drinking water is sourced from purchased surface water and supplied by BLACKLICK VALLEY MUNI AUTH. The system serves approximately 1,650 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Twin Rocks's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Twin Rocks's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Twin Rocks's water compare to other cities in Pennsylvania?
Twin Rocks's water quality score of 0/100 earns a grade of F, which is considered failing. This is a concerning score that suggests significant water quality issues. Visit our Pennsylvania state page to see how all cities in the state compare.
What should I do if I'm concerned about Twin Rocks's water quality?
If you have concerns about Twin Rocks's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (BLACKLICK VALLEY MUNI AUTH) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.