How can I locate a blockage in a 75' long 1-1/2" lawn sprinkler line without digging up the whole line?

Question

Is there an easy way to locate a blockage in the 75' long 1-1/2" underground feeder line to one of my lawn sprinkler zones? Water does reach that zone this year, but at considerably reduced pressure. The valve and solenoid are fine, so I'm thinking that I may have a root strangle somewhere. I'd really like to avoid digging up the whole 75' line.

Answer 1

most likely clogged at a sprinkler head. take out the first head on the line where the pressure drops and then turn on the system to flush it out. clean filter in the head if it has one.

repeat on successive heads.

Hope that helps.

Answer 2

That would be a heck of a blockage. Any opening in the line that would allow that much of a root tangle would also make the water leak....a lot!

Try a couple of other things first. Remove the sprinklers heads on that circuit and make sure that the screens and the nozzles are clean. Then remove or disassemble the valve itself and flush it out. If it is one of the types that you can get a rebuild kit for, install one now.

I am willing to bet you trouble is in one of these areas.

If you just have to check for a plug then do this: pull and cap all of the sprinkler heads on this circuit, then turn the water on. If there is any opening in the line that will allow something to plug the line, it will also allow water out. A large opening will show up as a puddle within a few minutes, a small one may take a few hours. But I really think that this is not the problem.

Answer 3

Run a fish tape or small plumbing snake down it.Measure how far to blockage.