Sewer line inspection

Hi everyone. Anybody have any advice about approaching a backflow preventer (not full port but small ABS flap one) with a sewer camera. Did one the other day and terminated the inspection because I didn’t want to get stuck on the return pull out. No other clean outs available so just would like to know if it was the right call. Jim Krumm?

We have to understand our limitations with sewer cameras. Equipment costs money and sacrificing your equipment is not what we should do. Catching and damaging the spring on the way out is a real possibility, you might even lose the camera head. Sometimes you just can’t get there. Setting expectations in advance with the client is helpful.

Good example why Licensed Plumbers (in my area) charge by the foot. If they need to abort, they still get paid for what they were able to scope. No more, no less. Just make sure this potential scenario is spelled out in your Contract and the “Scope to Scope” (like how I did that?).

Jim covered this in depth in the sewer scope training class. And there is a backflow preventer set up at the House of Horrors.

Though I’ve yet to come across one, so I have no real-world experience.

If I recall, on plastic/ABS one, have a bathtub filled, or similar way to flood the line. Finish the inspection, drain the tub so the line is flooded, and pull back. The water should keep the valve open long enough to pull back.

On a metal backflow preventer, he advised just stop and do not go past it.


You recalled the correctly. I also attended the sewer scope course and heard the same thing from Jim. The caveat is not to proceed; however, water manipulation should cause a plastic value to rise and enable the camera to return.

And I received the same as you; on a metal backflow preventer, do not enter.