Removing an Existing Valve Circuit

Q.  I have 3 zones for my sprinkler system.  I need to remove the valve/pipe/heads from one of the 3 zones in my backyard.

A. You may not even need to turn off the irrigation system water for this project.  But it is a good idea to know how to turn it off.  You never know when you may need to.

Definition:Zone valve” when used in irrigation, is the valve that turns on and off a group of sprinkler heads.  In most cases the zone valve is an electric activated valve and has a solenoid with wires leading into it on top of the valve.  The wires connect the zone valve to the irrigation controller (sometimes called the “timer” or “control box.”)  The power to the valve is typically 24 volts AC.  It usually will not harm most people if they touch a live wire, but it will give you enough of a shock that you will never want to do it again!  Obviously if you have a pacemaker or sensitivity to electrical current you will want to be extra careful around the wires.  If you touch your cell phone to a bare wire it may become an expensive paperweight.

Shut off the water. (Optional, if you are not going to remove the zone valve you don’t need to do this.)  Turn off the water to the entire sprinkler system.  Many sprinkler systems have a main shut off valve that turns off all the water to the sprinkler system.  Look around for the shut off valve.  It may be in a box underground.  Often it it near the location where the pipes enter the house.  Often it it in a basement if other water pipes are located in the basement.  Once you found a possible shut off valve, turn on one of your sprinkler zone valves so you can see that the system is running.  Now try turning off the possible shut-off valve.  It the sprinklers stop running you know the valve shuts off water to the sprinkler system.  Now check and see if it also turned off the water to the house.  If it did, you just found the house main water shut off valve.  You may not find a valve that turns off only the sprinkler water.  A lot of homeowner installed sprinkler systems don’t have them.  You may just have to turn off all the water to the house in order to work on the sprinkler system.

The easiest way is to leave the zone valve installed and not remove it.  Just plug it.  I’ll tell you how to do that first.

Identify the valve.  Now you need to figure out which of the sprinkler zone valves is the one you want to remove.  Hopefully you know where the valves are.  If not, see the article on how to find missing valves.   To determine which valve you want to remove, you manually turn on the zone valves (without using the control box) and see which one turns on the sprinkler you want to remove.  On top of your zone valves is a solenoid, written on it you will see ON/OFF arrows.  Turn the solenoid in the “ON” direction about 1/4 turn or so.  This should open the valve and the sprinklers should come on.  Note: Some valves have a lever that turns them on and off, some have a bleed screw you partially turn to make them manually open.  Each valve make and model is a little different, so you may have to use some deductive skills to figure out how to manually open your valve.  By turning them on one at a time you should be able to determine which valve operates the sprinklers you want to remove.  When finished, turn off the valve by by reversing the procedure you used to turn it on.  If your valve uses a bleed screw to open it, DO NOT completely remove the bleed screw.  Just unscrew it slowly until the valve turns on.

Typical sprinkler zone valves.
Typical sprinkler zone valves.

3. Now that you know which valve you want to remove, carefully dig the dirt away from the valve and expose the pipe on the downstream side of the zone valve. If you clear the dirt off the top of the zone valve it should have a flow direction arrow someplace on the valve body that points toward the outlet side.  (It may be on the side of the valve, using a small mirror makes it easier to find it.)

Once you know which direction the water flows through the valve, cut out a short section of the pipe right after the valve. Water may squirt out when you make the first cut into the pipe, so be prepared to get some muddy water sprayed at you!   A lot of water may drain out when you cut the pipe, depending on how much water was in the pipes and the slope of your yard.   You may have to bail water out of the hole with a bucket to remove it.  With the pipe section removed you can now use a wrench to unscrew the remaining pipe from the valve outlet.  Take the pipe section you removed from the valve (with the threads on it) to a hardware store and buy a threaded plug of the same size and a roll of Teflon tape.  Wrap several layers of the Teflon tape sealant onto the threads of the plug and then put the plug into the valve outlet opening.  Hand tighten the plug, then use the wrench to tighten it another half turn.  Do not overtighten it, if you overtighten the plug the valve body may split open.  Now that valve zone is plugged off.  You can remove the wires for that valve from the controller if you wish.  Now remove any of the pipe or sprinklers you want from that valve zone.

You can remove the entire valve if you want to.  I didn’t have you remove the valve because that does not require you to turn off the water to the entire sprinkler system, which is easier for most homeowners to do themselves.

To remove the entire valve:  Turn off the water to the entire sprinkler system.  Then manually turn ON the valve you want to remove, the sprinklers will come on for a few seconds then slowly shut off as the water discharges from the pipes and the pressure is released.  If the sprinklers keep running the water is not shut off!  Now follow the directions above.   Once the outlet pipe section is cut and removed, cut the wires off the valve, then unscrew and remove the entire valve.  Seal the ends of the wires with PVC glue or silicon caulk/sealer if you think you may ever want to use them again.   Put a threaded cap on the pipe that formerly connected to the valve.

Removing sprinklers.  To remove a sprinkler you can sometimes just grab the top of it and turn it counter-clockwise.  It will unscrew from the pipe below it and then you can lift it out of the ground.  Often you will need to dig away grass from it so you can twist it out.  In most cases you don’t need to dig a big hole around the sprinkler head, just dig away enough dirt and grass to allow you to grip the sprinkler.  Fill in the hole with dirt after you remove it.  Assuming you are abandoning the pipes, there is no need to cap the pipe off below the sprinkler, just leave it there.  If you don’t plan to ever use it, it doesn’t matter if it gets dirt in it.

Removing Pipes.  Most of the time we just leave the pipes in the ground.  They are a lot of work to remove and most of the time they don’t bother anyone if left buried.  If the pipes are not very deep you can often pull them up using “brute force”.  Dig down to expose the end of the pipe, grab the end and pull it up out of the ground.  If there is thick lawn you may need to cut a slit in the lawn surface to allow the pipe to be pulled up easier.  Use a edger to cut the turf directly above the pipe.  A string trimmer with heavy string in it may be able to cut the turf.  It may use up a lot of string!

I don’t recommend using a vehicle to pull the pipe out, but I know some will try it.  If you do this and get yourself injured or killed, you will be featured in those “knuckleheads in the news” columns!  If you try attaching a rope to the pipe and the other end to a garden tractor or truck to pull the pipe out of the ground – be very careful.  Wear protective clothing, gloves, eye protection and a hard hat.  Keep everyone else far away.  Have someone there watching from a distance who can call 911 if you get hurt!  Here’s why I say you shouldn’t do this:  Plastic pipe breaks suddenly and violently when pulled hard.  If the pipe or rope breaks while pulling on the pipe both the rope and the pipe can whip around violently and cause injury or damage, ie; break a window.  The white hard PVC plastic pipe can shatter and release small, very sharp pieces of plastic that act like shrapnel and cut like dozens of little knives.  If the pipe does not come out easily and you see the rope stretching, STOP, it’s going to break!  Don’t be an idiot, use common sense and extreme care.

If you can’t pull the pipe up and you absolutely can’t just abandon it in place, the only way I know of to get it out is to dig it out.  Ugghh.  Lots of work.