County · Kansas
Johnson County, Kansas: drinking water records
This overview covers 32 ZIP codes and 7 community water systems in Johnson County. It also stands in for 0 ZIP codes whose utility has too little EPA data for a page of its own.
System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.
Water systems with the most complete records
| Water system | People served | PFAS survey results | PFAS found | Health-based violations | Lead, 9 in 10 homes at or below |
|---|---|---|---|---|---|
| Desoto, City of KS2009102 | 4,645 | 60 | 1 | 3 | 0 ppb |
| Water District 1 of Johnson Co KS2009110 | 490,000 | 360 | 1 | 0 | 6.5 ppb |
| Olathe, City of KS2009115 | 143,014 | 120 | 0 | 0 | 11 ppb |
| Gardner, City of KS2009106 | 23,942 | 120 | 1 | 0 | 3.1 ppb |
| Johnson Co Rwd 7 KS2009104 | 6,457 | 360 | 1 | 0 | 2 ppb |
| Edgerton, City of KS2009103 | 1,741 | 0 | 0 | 0 | 5.2 ppb |
| Clearview City, City of KS2009123 | 450 | 0 | 0 | 0 | 0 ppb |
ZIP reports in Johnson County
No ZIP report in this county is published yet.
Sources and scope
EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.