Community Water System · PWSID PA4110077

Blacklick Valley Muni Auth

Serves 1,650 peopleSurface Water PurchasedOwner: Local GovernmentTwin Rocks, Pennsylvania
Nothing open that measures the water, but 1 open testing or paperwork violation.

A missed test is not evidence of bad water. It also is not evidence of good water: for that period nobody checked.

On record since 2005: 30 violations. 13 over the limit · 1 treatment lapse · 4 missed or late tests · 12 notices or reports. Most recent began 2025-10-11.

For this year's test results, ask the utility for its annual Consumer Confidence Report. Every community system must publish one.

13Over the limit
1Treatment lapse
4Missed or late test
12Notice or report1 open

More violations on record than 80% of active water systems in Pennsylvania. Small systems with no staff chemist often rack up missed-test violations; big utilities rarely do.

The record, year by year

2005 · Over the limit: 32005 · Over the limit: 32005 · Over the limit: 32005 · Missed or late test: 12005 · Notice or report: 32005 · Notice or report: 32005 · Notice or report: 320052007 · Missed or late test: 12008 · Over the limit: 12009 · Over the limit: 12009 · Notice or report: 12010 · Notice or report: 120102015 · Over the limit: 120152016 · Over the limit: 22016 · Over the limit: 22016 · Notice or report: 22016 · Notice or report: 22018 · Notice or report: 12019 · Over the limit: 12020 · Over the limit: 42020 · Over the limit: 42020 · Over the limit: 42020 · Over the limit: 42020 · Notice or report: 22020 · Notice or report: 220202021 · Notice or report: 12023 · Missed or late test: 12024 · Missed or late test: 12025 · Treatment lapse: 12025 · Notice or report: 12025
One square = one violation, by the year it began. Empty columns are years with nothing on EPA's record.
43% over the limit · 133% treatment lapse · 113% missed or late test · 440% notice or report · 12

Across Pennsylvania, 71% of violations are missed or late tests and 2% are water over a limit.

Lead & copper at the tap

Utilities sample taps in homes most likely to have lead pipes, and report the 90th-percentile result: 9 in 10 homes sampled came in at or below this number. Above the red line (the action level) the utility must act. The action level is not a safe level; EPA's health goal for lead is zero. EPA's file does not date these results, so they are shown highest first.

Lead, 90th percentile 1 result on file · action level 15 ppb

17 ppb

Open now (1)

  1. 2009-11-10Public NoticePN Violation for NPDWR ViolationOpen

Every violation on record

  1. 2025-10-11Public NoticePN Violation for NPDWR ViolationBack in compliance
  2. 2025-08-01Surface water treatment (SWTR)Treatment Technique (SWTR and GWR)Back in compliance
  3. 2024-10-01Revised Total Coliform RuleMONBack in compliance
  4. 2023-07-01Revised Total Coliform RuleMONPeriod ended · no return to compliance on file
  5. 2021-02-10Public NoticePN Violation for NPDWR ViolationBack in compliance
  6. 2020-11-10Public NoticePN Violation for NPDWR ViolationBack in compliance
  7. 2020-10-01Total Haloacetic Acids (HAA5)MCL, Averagemeasured 0.0690 MG/LBack in compliance
  8. 2020-08-10Public NoticePN Violation for NPDWR ViolationBack in compliance
  9. 2020-07-01Total Haloacetic Acids (HAA5)MCL, Averagemeasured 0.0960 MG/LBack in compliance
  10. 2020-04-01Total Haloacetic Acids (HAA5)MCL, Averagemeasured 0.1020 MG/LBack in compliance
  11. 2020-01-01Total Haloacetic Acids (HAA5)MCL, Averagemeasured 0.0960 MG/LBack in compliance
  12. 2019-10-01Total Haloacetic Acids (HAA5)MCL, Averagemeasured 0.0770 MG/LBack in compliance
  13. 2018-11-12Revised Total Coliform RuleRPTBack in compliance
  14. 2016-05-11Public NoticePN Violation for NPDWR ViolationBack in compliance
  15. 2016-04-01Total Haloacetic Acids (HAA5)MCL, AverageBack in compliance
  16. 2016-02-10Public NoticePN Violation for NPDWR ViolationBack in compliance
  17. 2016-01-01Total Haloacetic Acids (HAA5)MCL, AverageBack in compliance
  18. 2015-10-01Total Haloacetic Acids (HAA5)MCL, AverageBack in compliance
  19. 2010-02-10Public NoticePN Violation for NPDWR ViolationBack in compliance
  20. 2009-11-10Public NoticePN Violation for NPDWR ViolationOpen
  21. 2009-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0892 MG/LBack in compliance
  22. 2008-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0891 MG/LBack in compliance
  23. 2007-09-01Coliform (TCR)Monitoring, Repeat Minor (TCR)Back in compliance
  24. 2005-11-10Public NoticePN Violation for NPDWR ViolationBack in compliance
  25. 2005-08-10Public NoticePN Violation for NPDWR ViolationBack in compliance
Show the other 5 entries
  1. 2005-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1029 MG/LBack in compliance
  2. 2005-05-11Public NoticePN Violation for NPDWR ViolationBack in compliance
  3. 2005-04-01Trihalomethanes (TTHM)Monitoring and Reporting (DBP)Back in compliance
  4. 2005-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1021 MG/LBack in compliance
  5. 2005-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0923 MG/LBack in compliance

System details

Population served1,650
Service connections763
Water sourceSurface Water Purchased
System typeCommunity Water System
OwnerLocal Government
StatusActive
CityTwin Rocks
EPA ZIP on file15960

Areas served

  • Cambria County

Reading this record

Blacklick Valley Muni Auth is a community water system that draws from surface water purchased and serves about 1,650 people in Twin Rocks, Pennsylvania. Everything above comes from the EPA's Safe Drinking Water Information System (SDWIS), where states report every violation by every public water system.

Four kinds of violation. Only one is a measurement of the water: over the limit means a test came back above a legal maximum (an MCL). A treatment lapse means a required protective step was not done, such as disinfection, filtration, fixing a defect an inspector found, or filing a lead-pipe inventory. A missed or late test means a required test was skipped or never reported. That is the most common kind, and the most misread: it does not mean the water was bad, and it does not mean the water was fine. Notices and reports covers public notices and the annual Consumer Confidence Report.

Status. “Back in compliance” means the state recorded a return to compliance. “Period ended” means the violation's compliance period is over but no return to compliance was ever filed, which is common in older records. EPA's federal copy lags state records by months, so call the utility for anything current.