TTHM (Total Trihalomethanes) violations in Oregon
131 active public water systems in Oregon had a TTHM (Total Trihalomethanes) violation in the past three years, 6 of them in the latest quarter of EPA's data. What TTHM (Total Trihalomethanes) is and why it matters.
Systems with a TTHM (Total Trihalomethanes) violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Victoria Court Subdivision Jackson County |
70 | 4 | 0 | |
|
Salmon River RV Park Lincoln County |
69 | 6 | 1 | |
|
Clovercrest Community Water System Josephine County |
65 | 6 | 1 | |
|
Elk River Campground Curry County |
64 | 11 | 2 | |
|
King Silver RV Park Lincoln County |
62 | 8 | 1 | |
|
Gnr Water District Clackamas County |
60 | 3 | 1 | |
|
Welches Water Company Clackamas County |
60 | 9 | 0 | |
|
Zig Zag Water Co-Op Clackamas County |
60 | 2 | 0 | |
|
Ashland Valley Inn Jackson County |
59 | 6 | 2 | |
|
Lazy Days Mobile Home Park Lane County |
52 | 5 | 0 | |
|
McKenzie Palisades Water Board Lane County |
50 | 3 | 0 | |
|
Timberlab Laminators LLC Lane County |
50 | 2 | 0 | |
|
Taylors Landing RV Park Lincoln County |
48 | 6 | 1 | |
|
Hideaway Hills Water Company Clackamas County |
45 | 5 | 2 | |
|
River Village MHP Malheur County |
40 | 7 | 2 | |
|
South Yamhill Water District Yamhill County |
40 | 3 | 0 | |
|
Usfs McKenzie Work Center Lane County |
40 | 1 | 0 | |
|
Carmel Beach Water District Lincoln County |
39 | 4 | 0 | |
|
Jackson Creek Water Association Benton County |
39 | 6 | 0 | |
|
Mint Acres Water Co-Op Lane County |
35 | 5 | 1 | |
|
Alderwood Water Dev CO Lane County |
34 | 2 | 0 | |
|
Cascade Gorge Properties Jackson County |
33 | 8 | 1 | |
|
Galice Subdivision Water CO Josephine County |
33 | 13 | 3 | |
|
Latourell Falls Township Multnomah County |
32 | 6 | 2 | |
|
Lunnville Water District Yamhill County |
32 | 2 | 0 | |
|
Jasper Mountain Safe Center Lane County |
30 | 2 | 0 | |
|
Sunnycrest Meadows WS Yamhill County |
29 | 2 | 0 | |
|
Fox Hollow Estates Water Corp Marion County |
26 | 2 | 0 | |
|
Nantucket Shores Tillamook County |
25 | 9 | 1 | |
|
Pae Living Building Multnomah County |
25 | 6 | 1 | |
|
Hiland WC Wilderness Yamhill County |
20 | 3 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved TTHM (Total Trihalomethanes), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not TTHM (Total Trihalomethanes) alone.
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 Oregon 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.