How to Find Your Main Water Shut-Off Valve (and the One the City Owns)

Which valve is yours, and which one is the City’s?

Calgary homes have two shut-off points, and they have different owners.

The indoor main shut-off valve is yours. The City’s water service lines page says the homeowner is responsible for the main shut-off valve, which is normally inside the house. It is what you use in an emergency or when a leak, tap or toilet needs repair.

The outdoor service valve, sometimes called the curb stop, belongs to the City. The City states that service valves are owned and operated by The City of Calgary. It is usually in the front, back or side yard, such as in the lawn, driveway or private sidewalk, and sometimes just outside the back fence line in the alley.

The pipe between the two is where responsibility changes hands. The City says everything outside the property line is its responsibility, while the property owner pays for repairs to the service on private property, apart from the water meter. In most cases the property line ends a few metres from the edge of the curb or sidewalk.

Where is the main shut-off valve inside a Calgary home?

Sources describe a few common places, and your house may differ:

Because the City’s own pages describe slightly different spots, check all of them. Hot water tank rooms are a good first stop, and our page on hot water tank installation and repair in Calgary explains what sits around a tank. In a condo or townhome, the City’s frozen pipes page says to contact your building owner or manager when there is a flooding emergency.

How do you find it, step by step?

1. Go to the basement or lowest level. Start where the water line enters the house. The City describes the indoor main as being located where the water line enters the home.
2. Find the water meter. It is a small device with a dial or display. The City says the meter is connected to your water shut-off valve, so the valve is on the same pipe, just before or after it. EPCOR notes that of the two valves near its meter, the one to use is the one located before the meter on the pipe coming from the outside wall.
3. Check beside the hot water tank and in the furnace room. These are other places the City mentions.
4. Follow the pipe. Trace the incoming water line from the wall. The main shut-off is on that line, ahead of the branches that feed the rest of the house.
5. Look for a handle. You are looking for either a lever or a round wheel.
6. Check it is reachable. The City asks owners to protect the meter and valves, and advises insulating the main shut-off valve from cold surfaces such as concrete walls. Don’t store anything on the meter either, because the City says it can damage the register or the wire that sends information to the radio.
7. Mark it. Tape a tag nearby, or write the location on a household card. Add a photo of your own valve to the file.

Finding the outdoor valve is different. The City says to contact 311 to locate the service valve, for example before pouring a new driveway.

What does the valve look like and how does it turn?

You will usually find one of two types. A supplier’s valve guide describes them like this. A ball valve is a quarter-turn valve: the handle needs only a 90 degree turn, and the valve is open when the handle is parallel to the pipe and closed when it is perpendicular. A gate valve is a multi-turn valve, because it takes more than a 360 degree turn to open or close it entirely. It usually has a round handwheel.

EPCOR confirms that a gate valve or ball valve may be what you find. Our practical advice, not a rule from any source: turn a lever or wheel gently, and stop if it resists. The valve should close fully so that taps stop running.

What if the valve leaks or will not turn?

Do not force it. EPCOR notes that mineral deposits and grit can clog a home valve and make it hard to turn, and suggests hiring a professional plumber. The same page says homeowners are responsible for this valve, and that if it leaks or needs replacement the owner must have it fixed.

In Calgary, the City says an indoor valve repair needs a certified plumber, who must have the City shut off water at the outdoor service valve first. That is booked through the City’s Water Interruptions and Disconnections page, which lists fees.

For problems with the City’s own valve, such as one that needs raising or lowering, is missing a cap, or is damaged or leaking, the City says to submit an online service request or call 311. It also warns that freeze-thaw movement may mean the valve needs adjustment, sometimes more than once a year.

If a pipe is already spraying and the valve will not close, treat it as an emergency. Our guide on what to do when a pipe bursts lists the order of actions, and the City lists 311 for a flooding home on its frozen pipes page.

What should every household do about it?

Use this as a short household checklist:

• Locate the indoor main and tell everyone in the house where it is.
• Insulate it from cold concrete, as the City advises. Our guide on preventing frozen pipes in a Calgary winter covers the rest.
• Move anything blocking it, and keep the meter clear.
• Look at it once a year for drips, corrosion or stiffness. This is our suggestion, not a rule from the City. If you do try the handle, be gentle, and if it feels stuck or starts to drip, stop and call a plumber.
• Keep a plumber’s number somewhere visible. If the valve is old or hard to turn, ask a plumber to look at it.
• Know that the outdoor valve is the City’s. Report problems to 311, and never operate it.
• If you are planning a new driveway, the City says to schedule the pour at least 30 days after contacting 311 to locate the service valve and having it checked.

Knowing where the valve is can also help in a flood. Our guide on what to do when your basement floods explains when shutting the water off helps and when the problem is elsewhere.

Next step

If you have found your main valve, you are ahead of most homeowners. If you cannot find it, or it leaks or will not close, have it looked at by a licensed plumber. H2O Expert Plumbing is available 7 days a week. We inspect, explain what we find in plain language, and you approve a written quote before work starts, as set out on our plumbing services in Calgary page.

Call +1 (403) 700-4443, or request a free quote for planned work.