Community Water System · PWSID CA2410002

City of Dos Palos

Serves 7,452 peopleSurface WaterOwner: Local GovernmentDos Palos, California
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 2016: 35 violations. 30 over the limit · 4 treatment lapses · 1 missed or late test. Most recent began 2025-07-01.

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

30Over the limit
4Treatment lapse
1Missed or late test1 open
0Notice or report

More violations on record than 96% of active water systems in California. Small systems with no staff chemist often rack up missed-test violations; big utilities rarely do.

The record, year by year

2005201020152016 · Over the limit: 42016 · Over the limit: 42016 · Over the limit: 42016 · Over the limit: 42017 · Over the limit: 22017 · Over the limit: 22017 · Treatment lapse: 12018 · Over the limit: 22018 · Over the limit: 22019 · Over the limit: 32019 · Over the limit: 32019 · Over the limit: 32020 · Over the limit: 32020 · Over the limit: 32020 · Over the limit: 32020 · Treatment lapse: 32020 · Treatment lapse: 32020 · Treatment lapse: 320202021 · Over the limit: 52021 · Over the limit: 52021 · Over the limit: 52021 · Over the limit: 52021 · Over the limit: 52022 · Over the limit: 42022 · Over the limit: 42022 · Over the limit: 42022 · Over the limit: 42022 · Missed or late test: 12023 · Over the limit: 22023 · Over the limit: 22024 · Over the limit: 22024 · Over the limit: 22025 · Over the limit: 32025 · Over the limit: 32025 · Over the limit: 32025
One square = one violation, by the year it began. Empty columns are years with nothing on EPA's record.
86% over the limit · 3011% treatment lapse · 43% missed or late test · 1

Across California, 52% of violations are missed or late tests and 29% are water over a limit.

How far over the limit

at the limit2×5×10×100×+Trihalomethanes (TTHM)Total Haloacetic Acids (HAA5)2025-07-01 · Trihalomethanes (TTHM): measured 0.0892 MG/L vs limit 0.0800 MG/L (1.1×)2025-04-01 · Trihalomethanes (TTHM): measured 0.0878 MG/L vs limit 0.0800 MG/L (1.1×)2025-01-01 · Trihalomethanes (TTHM): measured 0.0931 MG/L vs limit 0.0800 MG/L (1.2×)2024-10-01 · Trihalomethanes (TTHM): measured 0.0984 MG/L vs limit 0.0800 MG/L (1.2×)2024-04-01 · Trihalomethanes (TTHM): measured 0.1036 MG/L vs limit 0.0800 MG/L (1.3×)2023-04-01 · Trihalomethanes (TTHM): measured 0.0840 MG/L vs limit 0.0800 MG/L (1.1×)2023-01-01 · Trihalomethanes (TTHM): measured 0.1070 MG/L vs limit 0.0800 MG/L (1.3×)2022-10-01 · Trihalomethanes (TTHM): measured 104.50 UG/L vs limit 0.0800 UG/L (1306.2×)2022-07-01 · Trihalomethanes (TTHM): measured 96.90 UG/L vs limit 80.00 UG/L (1.2×)2022-04-01 · Trihalomethanes (TTHM): measured 112.00 UG/L vs limit 80.00 UG/L (1.4×)2022-01-01 · Trihalomethanes (TTHM): measured 115.00 UG/L vs limit 80.00 UG/L (1.4×)2021-10-01 · Trihalomethanes (TTHM): measured 120.00 UG/L vs limit 80.00 UG/L (1.5×)2021-07-01 · Trihalomethanes (TTHM): measured 143.00 UG/L vs limit 80.00 UG/L (1.8×)2021-04-01 · Trihalomethanes (TTHM): measured 120.00 UG/L vs limit 80.00 UG/L (1.5×)2021-01-01 · Total Haloacetic Acids (HAA5): measured 98.00 UG/L vs limit 60.00 UG/L (1.6×)2021-01-01 · Trihalomethanes (TTHM): measured 108.00 UG/L vs limit 80.00 UG/L (1.4×)2020-10-01 · Trihalomethanes (TTHM): measured 106.00 UG/L vs limit 80.00 UG/L (1.3×)2020-07-01 · Trihalomethanes (TTHM): measured 93.40 UG/L vs limit 80.00 UG/L (1.2×)2020-04-01 · Trihalomethanes (TTHM): measured 0.0910 MG/L vs limit 0.0800 MG/L (1.1×)2019-10-01 · Trihalomethanes (TTHM): measured 0.1100 MG/L vs limit 0.0800 MG/L (1.4×)2019-04-01 · Trihalomethanes (TTHM): measured 0.0890 MG/L vs limit 0.0800 MG/L (1.1×)2019-01-01 · Trihalomethanes (TTHM): measured 0.1050 MG/L vs limit 0.0800 MG/L (1.3×)2018-10-01 · Trihalomethanes (TTHM): measured 0.1040 MG/L vs limit 0.0800 MG/L (1.3×)2018-07-01 · Trihalomethanes (TTHM): measured 0.0940 MG/L vs limit 0.0800 MG/L (1.2×)2017-04-01 · Trihalomethanes (TTHM): measured 97.00 UG/L vs limit 80.00 UG/L (1.2×)2017-01-01 · Trihalomethanes (TTHM): measured 0.1220 MG/L vs limit 0.0800 MG/L (1.5×)2016-10-01 · Trihalomethanes (TTHM): measured 125.00 UG/L vs limit 80.00 UG/L (1.6×)2016-07-01 · Trihalomethanes (TTHM): measured 132.00 UG/L vs limit 80.00 UG/L (1.6×)2016-04-01 · Trihalomethanes (TTHM): measured 150.00 UG/L vs limit 80.00 UG/L (1.9×)2016-01-01 · Trihalomethanes (TTHM): measured 147.00 UG/L vs limit 80.00 UG/L (1.8×)
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

0 ppb
0 ppb
0 ppb
0 ppb

Open now (1)

  1. 2022-10-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen

Every violation on record

  1. 2025-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0892 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  2. 2025-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0878 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  3. 2025-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0931 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  4. 2024-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0984 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  5. 2024-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1036 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  6. 2023-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0840 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  7. 2023-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1070 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/ROpen
  9. 2022-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 104.50 UG/L · limit 0.0800 UG/LPeriod ended · no return to compliance on file
  10. 2022-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 96.90 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  11. 2022-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 112.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  12. 2022-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 115.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  13. 2021-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 120.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  14. 2021-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 143.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  15. 2021-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 120.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  16. 2021-01-01Total Haloacetic Acids (HAA5)MCL, Averagemeasured 98.00 UG/L · limit 60.00 UG/LPeriod ended · no return to compliance on file
  17. 2021-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 108.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  18. 2020-10-01Carbon, TotalTreatment Technique Precursor RemovalPeriod ended · no return to compliance on file
  19. 2020-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 106.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  20. 2020-07-01Carbon, TotalTreatment Technique Precursor RemovalPeriod ended · no return to compliance on file
  21. 2020-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 93.40 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  22. 2020-04-01Carbon, TotalTreatment Technique Precursor RemovalPeriod ended · no return to compliance on file
  23. 2020-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0910 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  24. 2019-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1100 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  25. 2019-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0890 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
Show the other 10 entries
  1. 2019-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1050 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  2. 2018-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1040 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  3. 2018-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0940 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  4. 2017-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 97.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  5. 2017-01-01Surface water treatment (SWTR)Treatment Technique (SWTR and GWR)Back in compliance
  6. 2017-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1220 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  7. 2016-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 125.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  8. 2016-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 132.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  9. 2016-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 150.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file
  10. 2016-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 147.00 UG/L · limit 80.00 UG/LPeriod ended · no return to compliance on file

System details

Population served7,452
Service connections2,525
Water sourceSurface Water
System typeCommunity Water System
OwnerLocal Government
StatusActive
CityDos Palos
EPA ZIP on file93620

Areas served

  • Dos Palos, Merced County

Reading this record

City of Dos Palos is a community water system that draws from surface water and serves about 7,452 people in Dos Palos, California. 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.