Community Water System · PWSID LA1085032

Town of Zwolle Water System

Serves 2,520 peopleGroundwaterOwner: Local GovernmentZwolle, Louisiana
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 1993: 38 violations. 19 over the limit · 8 treatment lapses · 4 missed or late tests · 7 notices or reports. Most recent began 2025-02-12.

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

19Over the limit
8Treatment lapse
4Missed or late test
7Notice or report1 open

More violations on record than 89% of active water systems in Louisiana. Small systems with no staff chemist often rack up missed-test violations; big utilities rarely do.

The record, year by year

1993 · Over the limit: 11993 · Missed or late test: 119951996 · Over the limit: 11997 · Over the limit: 12000 · Notice or report: 12000200520102015 · Missed or late test: 120152016 · Over the limit: 12017 · Over the limit: 12018 · Over the limit: 22020 · Over the limit: 120202021 · Over the limit: 42021 · Over the limit: 42021 · Treatment lapse: 72021 · Treatment lapse: 72021 · Treatment lapse: 72021 · Treatment lapse: 72021 · Notice or report: 22022 · Over the limit: 22022 · Treatment lapse: 12022 · Missed or late test: 12022 · Notice or report: 32022 · Notice or report: 32023 · Over the limit: 12024 · Over the limit: 42024 · Over the limit: 42024 · Missed or late test: 12025 · Notice or report: 12025
One square ≈ 2 violations (rounded up), by the year they began. Empty columns are years with nothing on EPA's record.
50% over the limit · 1921% treatment lapse · 811% missed or late test · 418% notice or report · 7

Across Louisiana, 31% of violations are missed or late tests and 25% are water over a limit.

How far over the limit

at the limit2×5×10×100×+Trihalomethanes (TTHM)2024-10-01 · Trihalomethanes (TTHM): measured 0.0860 MG/L vs limit 0.0800 MG/L (1.1×)2024-07-01 · Trihalomethanes (TTHM): measured 0.0880 MG/L vs limit 0.0800 MG/L (1.1×)2024-04-01 · Trihalomethanes (TTHM): measured 0.1010 MG/L vs limit 0.0800 MG/L (1.3×)2024-01-01 · Trihalomethanes (TTHM): measured 0.1040 MG/L vs limit 0.0800 MG/L (1.3×)2023-10-01 · Trihalomethanes (TTHM): measured 0.0840 MG/L vs limit 0.0800 MG/L (1.1×)2022-04-01 · Trihalomethanes (TTHM): measured 0.0830 MG/L vs limit 0.0800 MG/L (1.0×)2022-01-01 · Trihalomethanes (TTHM): measured 0.0900 MG/L vs limit 0.0800 MG/L (1.1×)2021-10-01 · Trihalomethanes (TTHM): measured 0.1110 MG/L vs limit 0.0800 MG/L (1.4×)2021-07-01 · Trihalomethanes (TTHM): measured 0.1130 MG/L vs limit 0.0800 MG/L (1.4×)2021-04-01 · Trihalomethanes (TTHM): measured 0.0870 MG/L vs limit 0.0800 MG/L (1.1×)2021-01-01 · Trihalomethanes (TTHM): measured 0.0830 MG/L vs limit 0.0800 MG/L (1.0×)2020-04-01 · Trihalomethanes (TTHM): measured 0.0880 MG/L vs limit 0.0800 MG/L (1.1×)2018-07-01 · Trihalomethanes (TTHM): measured 90.00 UG/L vs limit 80.00 UG/L (1.1×)2018-01-01 · Trihalomethanes (TTHM): measured 89.00 UG/L vs limit 80.00 UG/L (1.1×)2017-04-01 · Trihalomethanes (TTHM): measured 101.00 UG/L vs limit 80.00 UG/L (1.3×)2016-01-01 · Trihalomethanes (TTHM): measured 83.00 UG/L vs limit 80.00 UG/L (1.0×)
Each dot is one over-the-limit violation: the measured value divided by the limit it broke, on a log scale. Most legal limits for chemicals are running averages set for a lifetime of drinking, so “just over” and “ten times over” are very different news. Hover a dot for the numbers.

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 4 results on file · action level 15 ppb

2 ppb
2 ppb
1 ppb
0 ppb

Open now (1)

  1. 2025-02-12Public NoticePN Violation for NPDWR ViolationOpen

Every violation on record

  1. 2025-02-12Public NoticePN Violation for NPDWR ViolationOpen
  2. 2024-11-13Lead and Copper RuleLead Consumer NoticeBack in compliance
  3. 2024-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0860 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  4. 2024-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0880 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  5. 2024-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1010 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  6. 2024-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1040 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  7. 2023-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0840 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  8. 2022-10-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  9. 2022-05-22Public NoticePN Violation for NPDWR ViolationBack in compliance
  10. 2022-05-04Public NoticePN Violation for NPDWR ViolationBack in compliance
  11. 2022-04-15Revised Total Coliform RuleTTBack in compliance
  12. 2022-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0830 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  13. 2022-02-16Public NoticePN Violation for NPDWR ViolationBack in compliance
  14. 2022-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0900 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  15. 2021-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1110 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  16. 2021-08-11Public NoticePN Violation for NPDWR ViolationBack in compliance
  17. 2021-07-02Groundwater Rule ×7Failure To Address DeficiencyBack in compliance
  18. 2021-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1130 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  19. 2021-05-05Public NoticePN Violation for NPDWR ViolationBack in compliance
  20. 2021-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0870 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  21. 2021-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0830 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  22. 2020-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0880 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  23. 2018-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 90.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  24. 2018-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 89.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  25. 2017-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 101.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
Show the other 7 entries
  1. 2016-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 83.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  2. 2015-05-01Coliform (TCR)Monitoring, Routine Major (TCR)Back in compliance
  3. 2000-07-01Consumer Confidence RuleCCR Complete Failure to ReportBack in compliance
  4. 1997-08-15Coliform (TCR)MCL, Monthly (TCR)Back in compliance
  5. 1996-11-15Coliform (TCR)MCL, Monthly (TCR)Back in compliance
  6. 1993-01-15Coliform (TCR)Monitoring, Repeat Minor (TCR)Back in compliance
  7. 1993-01-15Coliform (TCR)MCL, Monthly (TCR)Back in compliance

System details

Population served2,520
Service connections840
Water sourceGroundwater
System typeCommunity Water System
OwnerLocal Government
StatusActive
CityZwolle
EPA ZIP on file71486

Areas served

  • Sabine Parish

Reading this record

Town of Zwolle Water System is a community water system that draws from groundwater and serves about 2,520 people in Zwolle, Louisiana. 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.