Below is the incoming supply line from the municipal water. I noticed that the shut-off valve is very slowly leaking at the [???] shaft of the knob that turns (almost exactly where the point of the yellow arrow indicates)

My question - Let's say it's time to replace it. How does one do that? I know of no other way to shut off the incoming water.

enter image description here

  • 4
    There should be a shutoff somewhere outside at the edge of your property. Call your water company to schedule a shut-off. Sometimes they will even let you do it yourself if you have the correct tool.
    – MonkeyZeus
    Jun 3, 2021 at 19:22
  • Note that you can buy the tool at most hardware stores. If your street shutoff valve is accessible, this is a valuable and inexpensive last resort for stopping flow in case your main shutoff valve fails.
    – zaen
    Jun 4, 2021 at 13:50
  • Be very cautious about using a street key yourself. City utility officials often take a very dim view of homeowners that operates those shutoffs without permission. Depending on how slowly the valve is leaking, you might have some luck if you just open and close it a few times, then firmly open it all the way and leave it alone for a few weeks. Eventually it will get plugged up with minerals from the water, and the leak will stop.
    – Z4-tier
    Jun 6, 2021 at 22:22

4 Answers 4


This is the shutoff valve for your "house" not your residence.

So before this the city has their main shut-off in the front yard (98% of the time) and then probably an outside hose bib (90% of the time) and then this shutoff that shuts off everything inside your house.

You can always call the water company and ask them. But most companies will not replace this for you. Some do it as a service and some have contractors (reduced rates) they will point you to for house shut-off. These screw shutoffs fail all of the time and my water company will actually replace it for you for $25 or free if you are an old lady as they normally come out to turn off the main during this anyway. That isn't normal though so either call and hope for best, call a plumber ($100 if it isn't urgent) or try to replace yourself (have to shut off main to do this).

  • You guys are right - big metal thing smack in the front of my lawn. Forgot about that for some reason.
    – GWR
    Jun 3, 2021 at 20:18
  • 7
    Trick: If you are not an old lady, but you know someone who is, have her come to your house when the service people are scheduled, and let her answer the door instead of you. Jun 4, 2021 at 13:59
  • Now I'm wondering what happens if the main shut off needs to be replaced... is there another shut-off up the line? What if it needs to be replaced? Is it shut-off valves all the way back to the water tower?
    – Michael
    Jun 4, 2021 at 22:48
  • 2
    @Michael: of course. Otherwise you would have kilometers of continuous pipe below the streets, and every broken main (a daily occurrence in many places) would require shutting the water off city-wide. Jun 5, 2021 at 13:49

The stem packing is leaking, a standard repair. Try tightening the bronze hex nut . If that does not stop it, turn off the water , back off the hex nut to get more/new packing on the stem . I used several wraps of teflon tape pipe dope, works well although not approved by every one . I got the idea from an old guy in refinery maintenance. You may need to remove the red handle to lift the hex nut.

  • 6
    Absolutely. Given that it appears to be a branded and quality valve, it is probably built to be maintainable. Not everything is built for a throwaway society. Jun 4, 2021 at 3:05
  • It might even be possible to repack the gland without shutting off the water outside - I have done this once on a traditional British stop tap.
    – grahamj42
    Jun 4, 2021 at 6:16
  • Since it may be drinking water, please be sure you are using a sealing material that do not interact or degrade the quality of water.
    – EarlGrey
    Jun 4, 2021 at 11:52
  • 1
    Interesting! I'm ALL ABOUT fixing vs. replacing! Repack without shutting off water outside? How would that be done?
    – GWR
    Jun 4, 2021 at 12:01
  • @GWR, the gland nut on the valve I had only holds the packing in place, so I was able to undo it far enough to repack with the traditional knitting wool in vaseline without removing the handle - had to leave the valve part open to lift the nut enough and put up with the water seeping out while I packed it. My valve looked like this: media.screwfix.com/is/image//ae235?src=ae235/…. With your valve, I'd shut the water off.
    – grahamj42
    Jun 4, 2021 at 17:44

The homes in a neighborhood where I used to live, all built in the early 1950s, have no street-side shut-off valves that are accessible without digging up the street. Between jack hammers, laborers, city permits and re-paving, it costs thousands of dollars to access the street-side shut-off valve.

When the main shut-off valve in my basement failed (it no longer shut off the water completely), I opted to freeze the copper water main in my basement where it came up out of a sump in the basement floor. Freezing a short, straight length of soft copper pipe does not cause the pipe to burst. I made sure there was no water flowing anywhere in the house during the freezing process.

I built a gallon-sized cup around the water main about a foot below the bad valve by cutting up an old bleach bottle and reinforced it with duct tape. I filled the cup with pellets of dry ice and wrapped the whole thing in a towel.

After about an hour, the water main had an ice plug in it (evidenced by lack of flow when I opened a nearby faucet) and I cut the threaded brass pipe above the shut-off and installed a brass union and a new full-flow ball valve above the bad valve, leaving the old valve in place in the interest of finishing the job quickly, before the ice plug melted.

This is how licensed plumbers do it in that area, so as crazy as it may sound, it's the accepted practice.

  • 1
    "Freezing a short, straight length of soft copper pipe does not cause the pipe to burst". The pipes in my yard have about a foot of 3/4 copper pipe exposed. Every single winter that I forgot to drain that pipe after shutting it off, it burst and I had to do some plumbing. I'm wondering what's different. Jun 5, 2021 at 13:57
  • 2
    @MartinArgerami Perhaps your copper pipe was medium or hard temper like most straight lengths? If a foot is exposed to the air, more than a foot will freeze and that goes beyond the short length that I had in mind. My water main was dead soft 3/4" copper that comes in a big roll. Freezing a few inches in a straight section doesn't cause any damage because soft copper can deform without cracking. But if near an elbow or a T, all bets are off.
    – MTA
    Jun 5, 2021 at 15:16
  • Sounds reasonable, but not my experience. Jun 5, 2021 at 18:45
  • @MartinArgerami Pipes usually burst because a volume of water is first trapped so it can't "move out of the way" as the pipe continues to freeze. You probably trapped the water between the point where you "shut it off" and where the pipe started to freeze.
    – alephzero
    Jun 6, 2021 at 18:14
  • @alephzero: obviously, somehow it did happen. But the taps were open. Jun 6, 2021 at 18:44

The packing (5) is under the nut (4) on top of the valve body (12) where it seals between the stem (7) and valve body.

When the valve is closed you can bleed the pressure above the seat (9) by opening a valve, e.g. a faucet, inside the house, then closing it. After that you can remove the nut to access the packing with only minor dribbling from water above the valve inside the house. Do NOT open the shutoff valve while the packing nut is removed.

Clean up the stem so that it will seal more reliably, repack the valve, replace the nut and you'll be good to go.

enter image description here

  • 2
    Small consumer valves come in dozens of designs , so chances that it is like the diagram are slim. So the safe action is to turn off the main water. Jun 4, 2021 at 18:37
  • Solenoid-operated valves (e.g. watersavers.co.uk/water-solenoid-valves/water-shut-off-valves) are now becoming more common, since the shut-off switch can be in any convenient location, the seal can't be damaged by users over-tightening the valve, and the switch function can be automated, for example with a timer for an office building unoccupied at night and weekends.
    – alephzero
    Jun 6, 2021 at 18:40

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