Why the main shutoff comes first
A broken supply line under normal household pressure can put a surprising amount of water on the floor in the time it takes to find a phone number. Every minute it runs, water soaks further into drywall, baseboards, cabinets and, in slab-on-grade houses, the flooring laid directly on concrete. Closing the main stops all of it, no matter where the leak is.
The trouble is that most people have never touched their main valve. In an emergency they lose time searching for it, or they find a valve that has not moved in decades and is afraid to force it. Doing a dry run on a calm afternoon is the single most useful plumbing preparation a Brea household can make.
Where to look in a typical Brea house
Start at the side of the house that faces the street and work around.
- On an outside wall near the front or side hose bib, where the copper or galvanized line comes up out of the ground and into the house.
- Inside the garage, low on the wall that faces the street, sometimes behind shelving or a water softener.
- Near the water heater in older homes, where the supply was routed through the garage.
- In a small utility closet or under a hall cabinet in some newer homes.
- At the water meter box near the curb or sidewalk, which serves as the backup shutoff for the whole property.
Valve types and how to close them
| Valve | What it looks like | How to close it |
|---|---|---|
| Gate valve | Round wheel handle, common on older houses | Turn clockwise by hand until it stops. Several turns are normal. Do not use a wrench on the wheel if it resists. |
| Ball valve | Straight lever handle | Turn the lever a quarter turn so it sits across the pipe. Parallel means open, crossways means closed. |
| Meter valve | Flat tab or key fitting inside the meter box | Usually needs a meter key. Turn the tab a quarter turn so it sits across the line. |
| Fixture stops | Small oval handles under sinks and behind toilets | Turn clockwise. Useful when only one fixture is leaking and the rest of the house still needs water. |
Closing the main, step by step
- Confirm it is the right valve.It should be on the line coming from the street, before any branch to the house. If there is a pressure regulator, the shutoff is usually just upstream of it.
- Close it steadily.Turn a gate valve clockwise with even pressure, or swing a lever a quarter turn. Stop if something cracks, drips heavily or bends.
- Test it.Open a faucet on the lowest level. Flow should drop to a trickle and stop within a minute as the pipes drain.
- Protect the water heater.If the house will be without water for hours, turn the water heater to its vacation or pilot setting, or switch off the breaker on an electric unit.
- Leave it closed.Keep the main off until a licensed plumber has repaired or capped the leak. Reopen it slowly afterward so air and debris do not slam through the lines.
Which valve should you use?
- IfOnly one toilet, sink or appliance is leakingClose that fixture's stop valve and keep the rest of the house running.
- IfThe leak is inside a wall, ceiling or slabClose the main. You cannot isolate a hidden leak from a fixture valve.
- IfThe house main is stuck or brokenUse the meter valve at the street, with a meter key if you have one.
- IfWater is leaking at or before the meterContact your water provider. That section is usually not the homeowner's to repair.
Ask a plumber while they are there
- Is my main shutoff in good shape, or should it be replaced with a ball valve?
- Do I have a pressure regulator, and is it working?
- Can you tag the main and the water heater shutoffs so anyone in the house can find them?
- Is this valve work something that needs a permit? I will check with the City of Brea too.
Common questions
- How do I know if my main valve is fully closed?
- Open a low faucet. If water stops after the pipes drain, the main is closed. A steady stream means the valve is not sealing or you closed a branch valve instead.
- Can I buy a meter key?
- Meter keys are sold at hardware stores. Keep it near the front door so you are not hunting for it in the dark.
- Should I replace an old gate valve?
- Many plumbers suggest replacing a stiff or leaking gate valve with a quarter-turn ball valve. Ask a licensed plumber whether yours is worth replacing.
General information for Brea, not a quote or professional advice. In an emergency, call 911.