Rock City
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 2011: 4 violations. 3 missed or late tests · 1 notice or report. Most recent began 2025-07-01.
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.
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
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 4 results on file · action level 15 ppb
Open now (1)
- 2025-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
Every violation on record
- 2025-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
- 2023-07-01ChlorineMonitoring and Reporting (DBP)Back in compliance
- 2015-07-01Consumer Confidence RuleCCR Complete Failure to ReportBack in compliance
- 2011-01-02Lead and Copper RuleLead Consumer NoticeBack in compliance
System details
| Population served | 313 |
| Service connections | 128 |
| Water source | Groundwater |
| System type | Community Water System |
| Owner | Local Government |
| Status | Active |
| City | Davis |
| EPA ZIP on file | 61019 |
Areas served
- Rock City, Stephenson County
Reading this record
Rock City is a community water system that draws from groundwater and serves about 313 people in Davis, 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.