After having my sprinkler system winterized, I noticed water leaking from the spigot. I thought it would stop once all the extra water came out but it is still leaking after 1 week.

I turned the spigot to the off position and after about 30 minutes I noticed a slow leak coming from somewhere on top around the back flow area. Right now I have the spigot turned back on so the leak will come out from the spigot instead.

The main water shut off to the sprinkler system has been shut off from inside.

  • What can be causing this slow leak?
  • What can I do to stop the leak just for winter without having to do any crazy repairs? In the picture its leaking from the red circle because originally the spigot was open to release leftover water. But the slow leak never went away. So I shut off the spigot and notice slow leaking coming either from the yellow area or blue area. It is hard to tell since my wall is wet. But to me it looks like leak from the blue circle. So right now I have my spigot (red circle) leaking . And hasn't stop for a few days now. [1]: https://i.stack.imgur.com/73ixC.jpg![enter image description here](https://i.stack.imgur.com/cbOMx.jpg)enter image description here

Another key note is the main sprinkler water valve inside the house is shut off and well as another valve closest to the wall of the sprinkler pipe is shut off as well. So two valves on the same pipe inside the house. Those don't have any leaks but I'm hoping they don't need any repairs?? I thought those would be preventing any water from going outside to the system.

Inside shut off valves are both off and not leaking. Another member mention this might be the issue. They are both not leaking. Since being shut off for winterizing.

. enter image description here

  • 1
    Could you edit your pic to indicate exactly where the water is currently leaking from? Is it a joint, or a valve stem, or some other location? Draw an arrow or circle to indicate the precise spot that the water is escaping from.
    – FreeMan
    Nov 12, 2020 at 12:32
  • That helps. Now that you mention it, I can see the water on the wall. Since it's above the valve in the blue circle, the only way it could get there would either be by spraying from the blue valve or by dripping down from the yellow circle area. Since you indicate a slow leak, it's coming from the yellow circled area.
    – FreeMan
    Nov 12, 2020 at 13:37
  • Yes. So after careful monitoring I do notice that the more I close the spigot I started getting leak from the yellow area. But where is this water coming from?downstairs from my main sprinkler valve shutoff? Can I assume that Valve shut off is not doing its job and releasing water slowly outside to my (probably also busted) backflow unit.
    – Xao yang
    Nov 12, 2020 at 15:27

2 Answers 2


Your main shut-off is leaking ( not shown ) into the system. Until it completely stops water flow ,leave the red hose bibb open to prevent water from going into the rest of the sprinkler system. I would also open the unmarked blue handle valve to help the sprinkler system drain.

  • Yes. After more investigation. Shutting every of those handles off or on at its own time. There's still a leak. I do have the main shut off water valve for the sprinkler shut off . (Its a red circle nob). From what I notice that nob cannot do a complete 360 turn??? And there's also another nob closer to the wall on the same pip but it's a handle nob.. both have been in the off position as far as I know for a week and half now. But I have not notice any leaks..
    – Xao yang
    Nov 12, 2020 at 17:07
  • I meant that although your main sprinkler valve is in the off position ,it is leaking past the seat . It needs a repair , possibly a new rubber washer will do it. It would be necessary to shut of water to do that, probably the main valve for the whole house. Nov 12, 2020 at 20:51

Obviously, your main sprinkler shutoff valve in the basement is leaking allowing water to leak into the vacuum breaker and out through the bell cap on the the backflow preventer.
You will need to isolate the sprinkler shutoff in the house and repair/replace the valve. In the meantime you should close the circled blue handled ball valve on the vertical pipe and open the hose bibb circled in red. This will keep the supply line drained and prevent any water from entering the vacuum breaker until you complete the repair..

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.