Backflow testing in Oregon
2 utility lists · 42 companies. Largest list: Clackamas River Water (30 companies). Your utility decides which testers it accepts, so start from the utility that sent your notice.
Utility lists in Oregon, ranked by companies on the list
| Rank in state | Utility list | Area | Companies | Testers | vs national median | National rank (by companies) |
|---|---|---|---|---|---|---|
| 1 | Clackamas River Water | Clackamas | 30 | Company-level list | 0.5× | 27 of 33 |
| 2 | City of Cornelius | Cornelius | 15 | Company-level list | 0.3× | 30 of 33 |
Computed from the 2 Oregon utility lists above, as fetched 2026-11-04 (UTC). National median: 57 companies per list across the 33 utility lists we hold (n=33). National rank 1 = the list naming the most companies; equal counts share a rank. Testers: only lists that name each company's testers carry a count.
How current each list is
| Utility list | Version as printed | Date and age | Fetched (UTC) | We re-check it every |
|---|---|---|---|---|
| City of Cornelius | “2026 (PDF created 24 Sep 2026)” | 2026-09-24 (PDF file created date; the list prints no full date), 41 days before we fetched it; 5 of 22 by recency | 2026-11-04 | 365 days |
| Clackamas River Water | “undated (PDF created 28 Jul 2026)” | 2026-07-28 (PDF file created date; the list prints no full date), 99 days before we fetched it; 9 of 22 by recency | 2026-11-04 | 365 days |
Computed from the 2 Oregon utility lists above, as fetched 2026-11-04 (UTC). Median age at fetch across the 22 lists we hold that carry a date: 206 days (n=22); rank 1 = the most recently dated list. A month-only or two-digit version (for example “7.2026”) is shown as printed and not turned into a date.
Where the listed companies are based
15 companies on Oregon lists print a town (15 of 42), spread over 9 towns. The most common:
- Portland: 4 companies
- Forest Grove: 3 companies
- Hillsboro: 2 companies
- Beaverton: 1 company
- Fairview: 1 company
- Lake Oswego: 1 company
- City of Cornelius: 0 of 15 companies with a printed town (0%) are in Cornelius, the utility’s home city.
Computed from the 2 Oregon utility lists above, as fetched 2026-11-04 (UTC). Towns as each list prints them; a company named on two lists counts once.
Companies on more than one list
3 companies of the 42 on Oregon lists are named on more than one of them:
- Clackamas River Water and City of Cornelius: 3 companies on both (10% of the first list, 20% of the second).
Computed from the 2 Oregon utility lists above, as fetched 2026-11-04 (UTC). Matched by our company record (same name plus a shared ZIP code or phone number on the lists).
What kind of businesses are on the lists
The biggest difference from all the lists we hold: “backflow or cross-connection” appears in 50% of company names on Oregon lists, against 24% across all of them.
| Company name contains | Companies (42) | Share | Share, all 2,590 companies we hold |
|---|---|---|---|
| Plumbing | 5 | 12% | 25% |
| Backflow or cross-connection | 21 | 50% | 24% |
| Fire | 10 | 24% | 17% |
| Irrigation, lawn, landscape or sprinkler | 7 | 17% | 10% |
| Mechanical, heating or air | 0 | 0% | 6% |
Computed from the 2 Oregon utility lists above, as fetched 2026-11-04 (UTC). A company named on two lists counts once. A name can match more than one row; 5 names here match none. The words say nothing about the quality of the work.
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