Community Water System · PWSID CA2810013

Berryessa Highlands

Serves 715 peopleSurface WaterOwner: Local GovernmentNapa, California
Nothing open right now.

On record since 2014: 24 violations. 19 over the limit · 4 missed or late tests · 1 notice or report. Most recent began 2024-08-01.

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

19Over the limit
0Treatment lapse
4Missed or late test
1Notice or report

More violations on record than 94% 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

200520102014 · Missed or late test: 22014 · Missed or late test: 22014 · Notice or report: 120152016 · Over the limit: 52016 · Over the limit: 52016 · Over the limit: 52016 · Over the limit: 52016 · Over the limit: 52017 · Over the limit: 42017 · Over the limit: 42017 · Over the limit: 42017 · Over the limit: 42018 · Over the limit: 42018 · Over the limit: 42018 · Over the limit: 42018 · Over the limit: 42019 · Over the limit: 42019 · Over the limit: 42019 · Over the limit: 42019 · Over the limit: 42020 · Over the limit: 22020 · Over the limit: 22020 · Missed or late test: 120202024 · Missed or late test: 12025
One square = one violation, by the year it began. Empty columns are years with nothing on EPA's record.
79% over the limit · 1917% missed or late test · 44% notice or report · 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)2020-04-01 · Trihalomethanes (TTHM): measured 0.0823 MG/L vs limit 0.0800 MG/L (1.0×)2020-01-01 · Trihalomethanes (TTHM): measured 0.0863 MG/L vs limit 0.0800 MG/L (1.1×)2019-10-01 · Trihalomethanes (TTHM): measured 0.0870 MG/L vs limit 0.0800 MG/L (1.1×)2019-07-01 · Trihalomethanes (TTHM): measured 0.0845 MG/L vs limit 0.0800 MG/L (1.1×)2017-01-01 · Trihalomethanes (TTHM): measured 0.0867 MG/L vs limit 0.0800 MG/L (1.1×)2016-10-01 · Trihalomethanes (TTHM): measured 0.0910 MG/L vs limit 0.0800 MG/L (1.1×)2016-07-01 · Trihalomethanes (TTHM): measured 89.25 UG/L vs limit 80.00 UG/L (1.1×)2016-04-01 · Trihalomethanes (TTHM): measured 89.00 UG/L vs limit 80.00 UG/L (1.1×)2016-01-01 · Trihalomethanes (TTHM): measured 89.00 UG/L vs limit 80.00 UG/L (1.1×)
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 5 results on file · action level 15 ppb

102.5 ppb
0 ppb
0 ppb
0 ppb
0 ppb

Every violation on record

  1. 2024-08-01Revised Total Coliform RuleMONPeriod ended · no return to compliance on file
  2. 2020-12-01Revised Total Coliform RuleMONPeriod ended · no return to compliance on file
  3. 2020-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0823 MG/L · limit 0.0800 MG/LBack in compliance
  4. 2020-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0863 MG/L · limit 0.0800 MG/LBack in compliance
  5. 2019-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0870 MG/L · limit 0.0800 MG/LBack in compliance
  6. 2019-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0845 MG/L · limit 0.0800 MG/LBack in compliance
  7. 2019-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0910 MG/LBack in compliance
  8. 2019-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 89.80 UG/LBack in compliance
  9. 2018-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0900 MG/LBack in compliance
  10. 2018-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 91.80 UG/LBack in compliance
  11. 2018-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 84.30 UG/LBack in compliance
  12. 2018-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.1000 MG/LBack in compliance
  13. 2017-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0960 MG/LBack in compliance
  14. 2017-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0970 MG/LBack in compliance
  15. 2017-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0990 MG/LBack in compliance
  16. 2017-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0867 MG/L · limit 0.0800 MG/LBack in compliance
  17. 2016-10-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0910 MG/L · limit 0.0800 MG/LBack in compliance
  18. 2016-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 89.25 UG/L · limit 80.00 UG/LBack in compliance
  19. 2016-04-01Total Haloacetic Acids (HAA5)MCL, Averagemeasured 61.60 UG/LBack in compliance
  20. 2016-04-01Trihalomethanes (TTHM)MCL, Averagemeasured 89.00 UG/L · limit 80.00 UG/LBack in compliance
  21. 2016-01-01Trihalomethanes (TTHM)MCL, Averagemeasured 89.00 UG/L · limit 80.00 UG/LBack in compliance
  22. 2014-02-01Public NoticePN Violation for NPDWR ViolationBack in compliance
  23. 2014-01-01Total Haloacetic Acids (HAA5)Monitoring, Routine (IDSE)Back in compliance
  24. 2014-01-01Trihalomethanes (TTHM)Monitoring, Routine (IDSE)Back in compliance

System details

Population served715
Service connections256
Water sourceSurface Water
System typeCommunity Water System
OwnerLocal Government
StatusActive
CityNapa
EPA ZIP on file94559

Areas served

  • Napa County

Reading this record

Berryessa Highlands is a community water system that draws from surface water and serves about 715 people in Napa, 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.