How we check

Primary sources only

Each utility page is built from that utility's own backflow or cross-connection program pages, its customer FAQ, its tester list and tester packet, its test report form or online reporting system, its fee schedule and the section of its city or county code that sets the rules. State hubs use the state agency's own rules and certification pages. We never copy facts from other directories, plumbers' blogs, reviews or search snippets.

Every section is dated

Under each section of a utility page you'll see the page that holds its facts and the day we checked it. If two official pages disagree, we use the program page first, then the code, then forms, and the newest dated version among equals.

Re-checks

Rules, fees and reporting systems change, sometimes mid-year. We re-check every utility page at least every 120 days. A page that hasn't been re-checked in that time is taken out of search results until it is.

What we leave out

We don't list testers' prices (they vary by company and assembly and change often), we don't rate or recommend testers, and we don't guess: when a utility doesn't publish something, the page says so or leaves it out.

Corrections

If you spot an error, email corrections@backflowrules.com with the page and, if you can, a link to the utility's current page. We check it against the source and fix it.