Community Water System · PWSID CA4810005

Suisun-Solano Water Authority

Serves 29,105 peopleSurface WaterOwner: Local GovernmentVacaville, California
1 open treatment violation.

Open for: Lead service line inventory. EPA counts treatment-technique violations as health-based: a required protective step was not done. It is not a measurement of contamination.

On record since 2023: 12 violations. 10 over the limit · 1 treatment lapse · 1 notice or report. Most recent began 2024-10-17.

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

10Over the limit
1Treatment lapse1 open
0Missed or late test
1Notice or report1 open

More violations on record than 89% 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

20052010201520202023 · Over the limit: 42023 · Over the limit: 42023 · Over the limit: 42023 · Over the limit: 42024 · Over the limit: 62024 · Over the limit: 62024 · Over the limit: 62024 · Over the limit: 62024 · Over the limit: 62024 · Over the limit: 62024 · Treatment lapse: 12024 · Notice or report: 12025
One square = one violation, by the year it began. Empty columns are years with nothing on EPA's record.
83% over the limit · 108% treatment lapse · 18% 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)2024-07-01 · Trihalomethanes (TTHM): measured 0.0870 MG/L vs limit 0.0800 MG/L (1.1×)2024-04-01 · Trihalomethanes (TTHM): measured 0.0810 MG/L vs limit 0.0800 MG/L (1.0×)2024-04-01 · Trihalomethanes (TTHM): measured 0.0910 MG/L vs limit 0.0800 MG/L (1.1×)2024-04-01 · Trihalomethanes (TTHM): measured 0.0840 MG/L vs limit 0.0800 MG/L (1.1×)2024-01-01 · Trihalomethanes (TTHM): measured 0.0930 MG/L vs limit 0.0800 MG/L (1.2×)2024-01-01 · Trihalomethanes (TTHM): measured 0.0830 MG/L vs limit 0.0800 MG/L (1.0×)2023-10-01 · Trihalomethanes (TTHM): measured 0.0880 MG/L vs limit 0.0800 MG/L (1.1×)2023-10-01 · Trihalomethanes (TTHM): measured 0.0900 MG/L vs limit 0.0800 MG/L (1.1×)2023-10-01 · Trihalomethanes (TTHM): measured 0.0860 MG/L vs limit 0.0800 MG/L (1.1×)2023-07-01 · Trihalomethanes (TTHM): measured 0.0820 MG/L vs limit 0.0800 MG/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 3 results on file · action level 15 ppb

0 ppb
0 ppb
0 ppb

Open now (2)

  1. 2024-10-17Lead service line inventoryTTOpen
  2. 2024-10-17Lead service line inventoryRPTOpen

Every violation on record

  1. 2024-10-17Lead service line inventoryTTOpen
  2. 2024-10-17Lead service line inventoryRPTOpen
  3. 2024-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0870 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file
  4. 2024-04-01Trihalomethanes (TTHM) ×3MCL, Averagemeasured 0.0810 MG/L · limit 0.0800 MG/LBack in compliance
  5. 2024-01-01Trihalomethanes (TTHM) ×2MCL, Averagemeasured 0.0930 MG/L · limit 0.0800 MG/LBack in compliance
  6. 2023-10-01Trihalomethanes (TTHM) ×3MCL, Averagemeasured 0.0880 MG/L · limit 0.0800 MG/LBack in compliance
  7. 2023-07-01Trihalomethanes (TTHM)MCL, Averagemeasured 0.0820 MG/L · limit 0.0800 MG/LPeriod ended · no return to compliance on file

System details

Population served29,105
Service connections8,713
Water sourceSurface Water
System typeCommunity Water System
OwnerLocal Government
StatusActive
CityVacaville
EPA ZIP on file95688-8834

Areas served

  • Solano County

Reading this record

Suisun-Solano Water Authority is a community water system that draws from surface water and serves about 29,105 people in Vacaville, 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.