Community Water System · PWSID IL0310630

Des Plaines

Serves 60,675 peopleSurface Water PurchasedOwner: Local GovernmentDes Plaines, Illinois
Nothing open that measures the water, but 2 open testing or paperwork violations.

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 2018: 4 violations. 1 missed or late test · 3 notices or reports. Most recent began 2025-07-02.

None of them is a measurement of contaminated water.

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

0Over the limit
0Treatment lapse
1Missed or late test1 open
3Notice or report1 open

More violations on record than 55% of active water systems in Illinois. Small systems with no staff chemist often rack up missed-test violations; big utilities rarely do.

The record, year by year

2005201020152018 · Notice or report: 120202024 · Missed or late test: 12025 · Notice or report: 22025 · Notice or report: 22025
One square = one violation, by the year it began. Empty columns are years with nothing on EPA's record.
25% missed or late test · 175% notice or report · 3

Across Illinois, 81% of violations are missed or late tests and 3% are water over a limit.

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 11 results on file · action level 15 ppb

8.6 ppb
4.7 ppb
3.4 ppb
2.8 ppb
2.7 ppb
2.1 ppb
2.1 ppb
0.32 ppb
0 ppb
0 ppb
0 ppb

Open now (2)

  1. 2025-07-01Consumer Confidence RuleCCR Inadequate ReportingOpen
  2. 2024-10-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen

Every violation on record

  1. 2025-07-02Lead service line inventoryRPTBack in compliance
  2. 2025-07-01Consumer Confidence RuleCCR Inadequate ReportingOpen
  3. 2024-10-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  4. 2018-07-01Consumer Confidence RuleCCR Complete Failure to ReportBack in compliance

System details

Population served60,675
Service connections17,051
Water sourceSurface Water Purchased
System typeCommunity Water System
OwnerLocal Government
StatusActive
CityDes Plaines
EPA ZIP on file60016

Areas served

  • Des Plaines, Cook County

Reading this record

Des Plaines is a community water system that draws from surface water purchased and serves about 60,675 people in Des Plaines, Illinois. 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.