this is over my head and I am calling a professional. but anyway, i turned off the main sprinkler line (i.e. when I try to turn on the sprinklers, they wont turn on) by turning the ball valve under the plastic green rectangular cap labeled "irrigation control valve". However, that same area (underneath the green rectangular cap) is still overfilling with water because after I vacuum out all the water, in 2 hours it refills again and now is overflowing towards the sidewalk. I turned off the front hose bib and back hose bib in the basement but i dont think these are related to turning off the sprinkler line but i just did it in case. I have the hunter electronic sprinkler panel in the garage and the line from that goes directly outside through the garage floor. I dont know where the backflow preventer is.

17:28 here. happy to help but need more details. Can you post photos of your 1) main water line entry and shut off for the house, 2) the place where the main feed for the sprinkler taps into the house water supply, 3) the back flow preventer for the sprinkler, and 4) the valve box you are having fill up? So you say you shut off the valve for the whole sprinkler system? Depending on the size of the system, (and assuming you got the system shut off fully) you could have gallons of water under pressure, and shutting off the supply means you still have that water under pressure in the pipe. It might take while for the pressure to dissipate through the leak, hence "still filling up with water." All depends on how big the pipe is and how many linear feet of it.

darn; it looks like it is still filling up with water, even after turning off the sprinkler line.

I just pumped out all the water. It is the sprinkler water line with the sprinkler shutoff valve inside. First I pumped out all the water without shutting off the sprinkler line valve inside and it refilled back with water in 2 hours. I pumped out the water again and this time I turned the sprinkler shutoff valve and it stayed not filled. It is behind the the main water line (i.e. metal cap on the street). Any idea why the irrigation shutoff valve box would fill up with water? Thanks.

Presumably, if this is constantly leaking, then you do not have a master valve that only allows water to feed the branch pipes when the system is on. So you will want to find your shut-off to the irrigation system. There *should* be a shutoff prior to or immediately after the backflow preventer that should be located where the water supply comes out of the house. Find that and shut it off. Otherwise you are wasting a lot of water.

Call an irrigation company NOT a plumber. At this time of year it will be hard to get on their schedule as they’re winterizing clients systems so one strategy is to pay for that service.

I noticed there was some leaking from a panel cover labeled as "irrigation control valve" that is at the edge of my front lawn. I opened it up and it is flooded inside and i see the white sprinkler line with a turn valve inside. I noticed the panel was leaking because it was leaking onto the front sidewalk and is always wet at that spot there. I have changed sprinkler heads and fixed split sprinkler lines but anybody have an idea how to approach this? should i just call a professional or a plumber? Thanks.