County · Michigan
Washtenaw County, Michigan: drinking water records
This overview covers 14 ZIP codes and 33 community water systems in Washtenaw 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 |
|---|---|---|---|---|---|
| Superior Township MI0006490 | 6,830 | 240 | 1 | 1 | 0 ppb |
| Ann Arbor MI0000220 | 123,851 | 120 | 3 | 0 | 2.3 ppb |
| Ypsilanti Community Utility Authority MI0007260 | 53,988 | 120 | 0 | 0 | 4.1 ppb |
| Pittsfield Township MI0005360 | 24,500 | 120 | 0 | 0 | 0 ppb |
| Saline MI0005900 | 9,158 | 60 | 0 | 0 | 0 ppb |
| Scio Township MI0005977 | 8,500 | 120 | 3 | 0 | 0 ppb |
| Milan MI0004380 | 7,363 | 60 | 0 | 0 | 5.1 ppb |
| Chelsea MI0001370 | 5,474 | 60 | 0 | 0 | 0 ppb |
| Dexter MI0001810 | 4,500 | 120 | 0 | 0 | 0 ppb |
| Augusta Township MI0000321 | 3,907 | 120 | 0 | 0 | 0 ppb |
| Saline Valley Farms MI0005901 | 375 | 0 | 0 | 1 | 0 ppb |
| Westbrook Apartments MI0007035 | 330 | 0 | 0 | 1 | 2 ppb |
| Regency at Whitmore Lake MI0067101 | 190 | 0 | 0 | 1 | 5 ppb |
| St. Louis Center MI0006325 | 56 | 0 | 0 | 4 | 0 ppb |
| Manchester MI0004020 | 2,150 | 0 | 0 | 0 | 4.9 ppb |
| Northville Crossing MI0040657 | 1,890 | 0 | 0 | 0 | 5 ppb |
| Loch Alpine Sanitary Authority MI0003940 | 1,506 | 0 | 0 | 0 | 7.2 ppb |
| Ann Arbor Township MI0000221 | 1,338 | 0 | 0 | 0 | 1.1 ppb |
| Colonial Gardens Mobile Home Ct KS2016118 | 1,200 | 0 | 0 | 0 | 0 ppb |
| Thornton Farms MI0006594 | 1,188 | 0 | 0 | 0 | 3 ppb |
| Andelina Farms MI0000215 | 750 | 0 | 0 | 0 | 4 ppb |
| Orchard Grove MI0040503 | 725 | 0 | 0 | 0 | 2 ppb |
| River Ridge - Saline MI0040663 | 720 | 0 | 0 | 0 | 2 ppb |
| Riverchase Mobile Home Park KS2016119 | 460 | 0 | 0 | 0 | 3.5 ppb |
| Barton Hills MI0000430 | 450 | 0 | 0 | 0 | 1 ppb |
ZIP reports in Washtenaw 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.