Community Water System · PWSID CA5400665

Del Oro River Island Serv Terr #1

Serves 1,280 peopleSurface WaterOwner: PrivateChico, California
Nothing open right now.

On record since 2002: 63 violations. 54 over the limit · 8 missed or late tests · 1 notice or report. Most recent began 2024-04-01.

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

54Over the limit
0Treatment lapse
8Missed or late test
1Notice or report

More violations on record than 98% 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

2002 · Over the limit: 12003 · Over the limit: 42003 · Over the limit: 42003 · Over the limit: 42003 · Over the limit: 42003 · Missed or late test: 12003 · Notice or report: 12004 · Over the limit: 62004 · Over the limit: 62004 · Over the limit: 62004 · Over the limit: 62004 · Over the limit: 62004 · Over the limit: 62004 · Missed or late test: 12005 · Over the limit: 42005 · Over the limit: 42005 · Over the limit: 42005 · Over the limit: 42005 · Missed or late test: 32005 · Missed or late test: 32005 · Missed or late test: 320052006 · Over the limit: 12007 · Over the limit: 22007 · Over the limit: 22007 · Missed or late test: 12008 · Over the limit: 120102012 · Missed or late test: 120152016 · Over the limit: 32016 · Over the limit: 32016 · Over the limit: 32016 · Missed or late test: 12017 · Over the limit: 32017 · Over the limit: 32017 · Over the limit: 32018 · Over the limit: 32018 · Over the limit: 32018 · Over the limit: 32019 · Over the limit: 42019 · Over the limit: 42019 · Over the limit: 42019 · Over the limit: 42020 · Over the limit: 42020 · Over the limit: 42020 · Over the limit: 42020 · Over the limit: 420202021 · Over the limit: 42021 · Over the limit: 42021 · Over the limit: 42021 · Over the limit: 42022 · Over the limit: 42022 · Over the limit: 42022 · Over the limit: 42022 · Over the limit: 42023 · Over the limit: 72023 · Over the limit: 72023 · Over the limit: 72023 · Over the limit: 72023 · Over the limit: 72023 · Over the limit: 72023 · Over the limit: 72024 · Over the limit: 32024 · Over the limit: 32024 · 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 · 5413% missed or late test · 82% 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×+Combined UraniumNitrate2024-04-01 · Combined Uranium: measured 41.30 PCI/L vs limit 20.00 PCI/L (2.1×)2024-04-01 · Nitrate: measured 13.00 MG/L vs limit 10.00 MG/L (1.3×)2024-01-01 · Combined Uranium: measured 39.20 PCI/L vs limit 20.00 PCI/L (2.0×)2023-10-01 · Combined Uranium: measured 44.00 PCI/L vs limit 20.00 PCI/L (2.2×)2023-08-01 · Nitrate: measured 13.00 MG/L vs limit 10.00 MG/L (1.3×)2023-07-01 · Combined Uranium: measured 42.30 PCI/L vs limit 20.00 PCI/L (2.1×)2023-07-01 · Nitrate: measured 11.30 MG/L vs limit 10.00 MG/L (1.1×)2023-06-01 · Nitrate: measured 11.70 MG/L vs limit 10.00 MG/L (1.2×)2023-04-01 · Combined Uranium: measured 42.80 PCI/L vs limit 20.00 PCI/L (2.1×)2023-01-01 · Combined Uranium: measured 44.10 PCI/L vs limit 20.00 PCI/L (2.2×)2022-10-01 · Combined Uranium: measured 44.70 PCI/L vs limit 20.00 PCI/L (2.2×)2022-07-01 · Combined Uranium: measured 46.00 PCI/L vs limit 20.00 PCI/L (2.3×)2022-04-01 · Combined Uranium: measured 47.30 PCI/L vs limit 20.00 PCI/L (2.4×)2022-01-01 · Combined Uranium: measured 47.50 PCI/L vs limit 20.00 PCI/L (2.4×)2021-10-01 · Combined Uranium: measured 48.00 PCI/L vs limit 20.00 PCI/L (2.4×)2021-07-01 · Combined Uranium: measured 48.50 PCI/L vs limit 20.00 PCI/L (2.4×)2021-04-01 · Combined Uranium: measured 46.80 PCI/L vs limit 20.00 PCI/L (2.3×)2021-01-01 · Combined Uranium: measured 43.80 PCI/L vs limit 20.00 PCI/L (2.2×)2020-10-01 · Combined Uranium: measured 43.00 PCI/L vs limit 20.00 PCI/L (2.1×)2020-07-01 · Combined Uranium: measured 41.80 PCI/L vs limit 20.00 PCI/L (2.1×)2020-04-01 · Combined Uranium: measured 42.00 PCI/L vs limit 20.00 PCI/L (2.1×)2020-01-01 · Combined Uranium: measured 43.60 PCI/L vs limit 20.00 PCI/L (2.2×)2019-10-01 · Combined Uranium: measured 41.80 PCI/L vs limit 20.00 PCI/L (2.1×)2019-07-01 · Combined Uranium: measured 41.60 PCI/L vs limit 20.00 PCI/L (2.1×)2019-04-01 · Combined Uranium: measured 41.80 PCI/L vs limit 20.00 PCI/L (2.1×)2019-01-01 · Combined Uranium: measured 42.80 PCI/L vs limit 20.00 PCI/L (2.1×)2018-07-01 · Combined Uranium: measured 45.00 PCI/L vs limit 20.00 PCI/L (2.2×)2018-04-01 · Combined Uranium: measured 45.00 PCI/L vs limit 20.00 PCI/L (2.2×)2018-01-01 · Combined Uranium: measured 41.00 PCI/L vs limit 20.00 PCI/L (2.0×)2017-10-01 · Combined Uranium: measured 31.00 PCI/L vs limit 20.00 PCI/L (1.6×)2017-07-01 · Combined Uranium: measured 32.40 PCI/L vs limit 20.00 PCI/L (1.6×)2017-07-01 · Nitrate: measured 12.10 MG/L vs limit 10.00 MG/L (1.2×)2016-07-01 · Combined Uranium: measured 31.40 PCI/L vs limit 20.00 PCI/L (1.6×)2016-04-01 · Combined Uranium: measured 31.60 PCI/L vs limit 20.00 PCI/L (1.6×)2016-01-01 · Combined Uranium: measured 33.40 PCI/L vs limit 20.00 PCI/L (1.7×)2008-01-01 · Nitrate: measured 48.00 MG/L vs limit 45.00 MG/L (1.1×)2007-10-01 · Nitrate: measured 51.00 MG/L vs limit 45.00 MG/L (1.1×)2007-07-01 · Nitrate: measured 46.00 MG/L vs limit 45.00 MG/L (1.0×)2006-07-01 · Nitrate: measured 64.00 MG/L vs limit 45.00 MG/L (1.4×)2005-07-01 · Nitrate: measured 65.00 MG/L vs limit 45.00 MG/L (1.4×)2005-04-01 · Nitrate: measured 47.00 MG/L vs limit 45.00 MG/L (1.0×)2005-01-01 · Nitrate: measured 64.00 MG/L vs limit 45.00 MG/L (1.4×)2004-12-01 · Nitrate: measured 61.00 MG/L vs limit 45.00 MG/L (1.4×)2004-07-01 · Nitrate: measured 46.00 MG/L vs limit 45.00 MG/L (1.0×)2004-04-01 · Nitrate: measured 46.00 MG/L vs limit 45.00 MG/L (1.0×)2003-10-01 · Nitrate: measured 64.10 MG/L vs limit 45.00 MG/L (1.4×)2003-04-01 · Nitrate: measured 48.30 MG/L vs limit 45.00 MG/L (1.1×)2003-01-01 · Nitrate: measured 53.00 MG/L vs limit 45.00 MG/L (1.2×)
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 6 results on file · action level 15 ppb

5.4 ppb
3.2 ppb
3.1 ppb
2.5 ppb
1.3 ppb
1.3 ppb

Every violation on record

  1. 2024-04-01Combined UraniumMCL, Averagemeasured 41.30 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  2. 2024-04-01NitrateMCL, Single Samplemeasured 13.00 MG/L · limit 10.00 MG/LPeriod ended · no return to compliance on file
  3. 2024-01-01Combined UraniumMCL, Averagemeasured 39.20 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  4. 2023-10-01Combined UraniumMCL, Averagemeasured 44.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  5. 2023-08-01NitrateMCL, Single Samplemeasured 13.00 MG/L · limit 10.00 MG/LPeriod ended · no return to compliance on file
  6. 2023-07-01Combined UraniumMCL, Averagemeasured 42.30 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  7. 2023-07-01NitrateMCL, Single Samplemeasured 11.30 MG/L · limit 10.00 MG/LPeriod ended · no return to compliance on file
  8. 2023-06-01NitrateMCL, Single Samplemeasured 11.70 MG/L · limit 10.00 MG/LPeriod ended · no return to compliance on file
  9. 2023-04-01Combined UraniumMCL, Averagemeasured 42.80 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  10. 2023-01-01Combined UraniumMCL, Averagemeasured 44.10 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  11. 2022-10-01Combined UraniumMCL, Averagemeasured 44.70 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  12. 2022-07-01Combined UraniumMCL, Averagemeasured 46.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  13. 2022-04-01Combined UraniumMCL, Averagemeasured 47.30 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  14. 2022-01-01Combined UraniumMCL, Averagemeasured 47.50 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  15. 2021-10-01Combined UraniumMCL, Averagemeasured 48.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  16. 2021-07-01Combined UraniumMCL, Averagemeasured 48.50 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  17. 2021-04-01Combined UraniumMCL, Averagemeasured 46.80 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  18. 2021-01-01Combined UraniumMCL, Averagemeasured 43.80 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  19. 2020-10-01Combined UraniumMCL, Averagemeasured 43.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  20. 2020-07-01Combined UraniumMCL, Averagemeasured 41.80 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  21. 2020-04-01Combined UraniumMCL, Averagemeasured 42.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  22. 2020-01-01Combined UraniumMCL, Averagemeasured 43.60 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  23. 2019-10-01Combined UraniumMCL, Averagemeasured 41.80 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  24. 2019-07-01Combined UraniumMCL, Averagemeasured 41.60 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  25. 2019-04-01Combined UraniumMCL, Averagemeasured 41.80 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
Show the other 38 entries
  1. 2019-01-01Combined UraniumMCL, Averagemeasured 42.80 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  2. 2018-07-01Combined UraniumMCL, Averagemeasured 45.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  3. 2018-04-01Combined UraniumMCL, Averagemeasured 45.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  4. 2018-01-01Combined UraniumMCL, Averagemeasured 41.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  5. 2017-10-01Combined UraniumMCL, Averagemeasured 31.00 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  6. 2017-07-01Combined UraniumMCL, Averagemeasured 32.40 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  7. 2017-07-01NitrateMCL, Single Samplemeasured 12.10 MG/L · limit 10.00 MG/LBack in compliance
  8. 2016-07-01Combined UraniumMCL, Averagemeasured 31.40 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  9. 2016-07-01NitrateMonitoring, RegularBack in compliance
  10. 2016-04-01Combined UraniumMCL, Averagemeasured 31.60 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  11. 2016-01-01Combined UraniumMCL, Averagemeasured 33.40 PCI/L · limit 20.00 PCI/LPeriod ended · no return to compliance on file
  12. 2012-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  13. 2008-01-01NitrateMCL, Single Samplemeasured 48.00 MG/L · limit 45.00 MG/LBack in compliance
  14. 2007-10-01NitrateMCL, Single Samplemeasured 51.00 MG/L · limit 45.00 MG/LBack in compliance
  15. 2007-07-01NitrateMCL, Single Samplemeasured 46.00 MG/L · limit 45.00 MG/LBack in compliance
  16. 2007-03-01Coliform (TCR)Monitoring, Routine Major (TCR)Back in compliance
  17. 2006-07-01NitrateMCL, Single Samplemeasured 64.00 MG/L · limit 45.00 MG/LBack in compliance
  18. 2005-10-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  19. 2005-07-01NitrateMCL, Single Samplemeasured 65.00 MG/L · limit 45.00 MG/LBack in compliance
  20. 2005-06-01Coliform (TCR)Monitoring, Routine Minor (TCR)Back in compliance
  21. 2005-04-01NitrateMCL, Single Samplemeasured 47.00 MG/L · limit 45.00 MG/LBack in compliance
  22. 2005-04-01Coliform (TCR)MCL, Monthly (TCR)Back in compliance
  23. 2005-01-01NitrateMCL, Averagemeasured 64.00 MG/L · limit 45.00 MG/LBack in compliance
  24. 2005-01-01NitrateMonitoring, RegularBack in compliance
  25. 2004-12-01NitrateMCL, Single Samplemeasured 61.00 MG/L · limit 45.00 MG/LBack in compliance
  26. 2004-07-01NitrateMCL, Single Samplemeasured 46.00 MG/L · limit 45.00 MG/LBack in compliance
  27. 2004-07-01Coliform (TCR)MCL, Monthly (TCR)Back in compliance
  28. 2004-04-01NitrateMCL, Single Samplemeasured 46.00 MG/L · limit 45.00 MG/LBack in compliance
  29. 2004-03-01Coliform (TCR)MCL, Monthly (TCR)Back in compliance
  30. 2004-01-01NitrateMonitoring, RegularBack in compliance
  31. 2004-01-01Coliform (TCR)MCL, Monthly (TCR)Back in compliance
  32. 2003-10-01NitrateMCL, Single Samplemeasured 64.10 MG/L · limit 45.00 MG/LBack in compliance
  33. 2003-07-01NitrateMonitoring, RegularBack in compliance
  34. 2003-07-01Consumer Confidence RuleCCR Complete Failure to ReportBack in compliance
  35. 2003-04-01NitrateMCL, Single Samplemeasured 48.30 MG/L · limit 45.00 MG/LBack in compliance
  36. 2003-04-01Coliform (TCR)MCL, Monthly (TCR)Back in compliance
  37. 2003-01-01NitrateMCL, Single Samplemeasured 53.00 MG/L · limit 45.00 MG/LBack in compliance
  38. 2002-12-01Coliform (TCR)MCL, Monthly (TCR)Back in compliance

System details

Population served1,280
Service connections388
Water sourceSurface Water
System typeCommunity Water System
OwnerPrivate
StatusActive
CityChico
EPA ZIP on file95927

Areas served

  • Tulare County

Reading this record

Del Oro River Island Serv Terr #1 is a community water system that draws from surface water and serves about 1,280 people in Chico, 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.