Water quality in Onalaska, Washington
Onalaska is in Lewis County. 167 active public water systems serve the county; 56 had an EPA violation in the past three years.
Most likely your provider
Your location is within the outer bounds of this system's EPA service area.
Other community water systems in Lewis County
50 systems, nearest first| System | Serves | Status | Rules violated, 3 yr | Distance |
|---|---|---|---|---|
| Middle Fork Water & Sewer |
144 | 0 | 3.4 mi | |
| Salkum Water Supply |
103 | 3 | 5.1 mi | |
| Jackson Mobile 2 |
30 | 1 | 5.5 mi | |
| Valley Meadows 240 |
148 | 0 | 6.9 mi | |
| Mayfield RV Park |
165 | 2 | 7.0 mi | |
| Winston Creek RV Park |
50 | 0 | 7.4 mi | |
| Mountain Lakeview 619 |
70 | 0 | 7.4 mi | |
| Lakeside Village |
94 | 0 | 8.1 mi | |
| Lake Mayfield Community Club |
88 | 0 | 8.1 mi | |
| Lakeview Terrace |
41 | 1 | 8.2 mi | |
| Silverbrook MH & RV |
42 | 0 | 8.3 mi | |
| Mayfield Kamper Klub |
87 | 0 | 8.5 mi | |
| Gunderson Water Works |
53 | 0 | 8.6 mi | |
| Lewis Co Water Sewer Dist #6 |
740 | 2 | 8.8 mi | |
| Newaukum Ventures |
186 | 1 | 8.8 mi | |
| Cowlitz Indian Tribal Housing |
52 | 1 | 9.3 mi | |
| Napavine City of |
3,095 | 1 | 9.4 mi | |
| Frost Road Park |
65 | 1 | 9.5 mi | |
| Harmony Park Lot Owners |
81 | 0 | 10.1 mi | |
| Aust 210 |
35 | 0 | 10.4 mi | |
| Timberlane Mobile Home Park |
63 | 1 | 10.9 mi | |
| Mossyrock Public Utility City of |
1,553 | 1 | 11.0 mi | |
| Parkwood Mobile Home Estates |
105 | 1 | 11.1 mi | |
| Winlock City of |
3,502 | 0 | 11.3 mi | |
| Toledo Municipal |
1,944 | 1 | 11.3 mi |
Non-community systems in Lewis County (116: schools, campgrounds, workplaces, restaurants)
These systems serve places you visit rather than homes.
About this data
Water systems are matched to Lewis County, nearest to Onalaska first. Your exact provider depends on your address and connection; the largest community water system in a county is usually the city or town utility. Distances are measured to the centre of the service area EPA publishes for the system.
Town locations and ZIP code areas come from U.S. Census Bureau 2020 files.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Washington records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.