I've owned my first home for a few years now, but have never truly known where my main water shutoff valve was, mainly because I've never really known how to identify it. I've looked around my utility room where my furnace, hot water heater, etc are, but nothing matches what I recall from my parent's home when they shut off the water there. For reference, my home was built in 1985.

After doing some searching via Google Images, this is what I believe might be the valve for my home: Overview

The area I've circled in red is what I believe to be the main shutoff valve, but wanted to confirm before I messed with anything (note: I do not have any need to do anything with this at this time, just something I'd like to know in the event of an emergency). There are many valves in my utility room with my washer, dryer, furnace, hot water heater, etc. But based off of the images I've found from Googling, this seems to match some of the examples I've seen.

Slight side note, I'm also slightly confused at what looks to be a ground wire going from the green circle in the above image to the blue circle in the above image. This seems unnecessary and / or abnormal, but I'm not too familiar with how any of this would be set up "properly". Here are some close ups: Bottom Right Wire Top Left Wire

2 Answers 2


Yes, that looks like your main shutoff valve. It's normally the first valve on your water supply from where it enters your house, and typically before the water meter. In my house there is another valve on the other side of the meter that makes it possible to swap out the meter without draining the house.

The copper wire is part of our house's grounding. It jumps around the meter and ensures that there is an electrically secure path "through" the meter. Because of the union joints and that some meter bodies are not electrically conductive, it provides a secure path. Also when the meter is being replaced.

  • Worth noting that depending on the materials of the meter, any electrical conductivity between it and the pipework is broken on purpose to prevent galvanic corrosion.
    – JMac
    Aug 14, 2019 at 13:06
  • 2
    Also worth noting that you should turn the valve fully open and then closing it a little (e.g. a quarter turn). This helps to stop the valve binding in the fully open position. (If it is already jammed it would be better to find out now instead of when water is spraying out somewhere!)
    – rolinger
    Aug 14, 2019 at 16:12
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    It may also be worth noting that in some places (I know every house in my city has it), there can be a second valve outside the building (mine is buried in the front yard), intended to be used if the main shutoff valve needs replacement. Where I live this valve is owned and maintained by the city itself and is also what they use as an emergency shutoff if needed.
    – mbrig
    Aug 14, 2019 at 19:03
  • @rolinger - I appreciate the additional words of warning. I tested the valve slightly by checking if it was already fully open and it mostly was. I then closed it 2 - 3 rotations and it seemed to rotate fairly easily. After that point there was a bit of tension, so I decided to stop as to not cause any issues; right now my water is working fine, I don't want to mess with anything too much and cause any unexpected side effects. Is that a fair test to ensure it's not "already jammed"?
    – William
    Aug 15, 2019 at 1:30
  • @mbrig - I can 100% confirm that is true for my situation. I know for a fact that I have a curb shut off valve towards the road in my front lawn. A year or so ago the town spray pained it blue and marked it with a blue flag. However, I do not have the tool to operate that value, nor do I want to do that since, from what I understand, it's supposed to be maintained by the town.
    – William
    Aug 15, 2019 at 1:36

Yes it is your main shut off valve. I'm assuming this is in a basement, from the looks. You're good on that.

The best experiment to prove this out is to turn the handle clockwise until it stops. This usually takes about 10 turns.

The wire attached is a grounding conductor which more than likely goes inside your breaker box .

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