A whole-house shutoff that no one labeled is not a plan. We still walk Covina and Walnut houses where three people point at three different valves and none of them stop the service. A slab leak weekend then starts with a hunt. Drain Doctor Plumbing & Rooter would rather label the valve that actually kills the house before the floor is wet.
This is not the remodel article about replacing a frozen valve before demolition. That already lives at replace the main shutoff before a remodel. This post is the unlabeled valve nobody can find tonight. Supply leaks route through water-line repair and plumbing repair.
If nobody can name the shutoff, the leak weekend is already slower
Photograph the meter, the house-side valve, and any painted or buried lid. Note who has a key if the meter box is locked. West Covina and Glendora homes often have a valve in a flower bed that looks like irrigation. It is not. Write which handle actually stopped the water when we tested it.
Heater closets have their own shutoffs. They do not stop a slab leak. See water heater when that tank is the leak. Drain backups are a different system.
Label the valve that actually stops the house
After we confirm it, we want a tag and a photo in the house file. If the valve will not turn, that is a replacement conversation, not a lecture. Call (626) 332-9984 or contact us. Coverage is on service area pages including Walnut and Rowland Heights. More reading is on the blog.
Label the Walnut shutoff while the house is dry. An unlabeled valve is how a small leak becomes a long night.