First sort out how much is out: the whole building, one tenant space or one fixture. Whole-building loss points to the utility, a closed or failed main valve, or a broken service line. A partial loss points to a closed zone valve or a local fault. Check valves and neighbors before anything else.
How wide is it?
| What is out | Where to look |
|---|---|
| Entire building, nothing flows | Utility outage, closed or failed main valve, broken service line |
| One tenant space or one wing | A closed zone or riser valve, or a local break |
| One fixture or one restroom | Fixture stop, strainer or aerator, or a failed branch |
| Water flows but weakly | Pressure problem, covered on its own page |
What can you check in ten minutes?
- 1Ask your neighbors. If nearby businesses are dry too, it is probably the utility. Phoenix Water Services notes that customers may see reduced pressure when there is construction in the area, including work on infrastructure that keeps water delivery safe and reliable. Call the utility before a plumber.
- 2Find the main valve and see if it is open. Phoenix tells customers to know where the shutoff is and test it regularly. Someone doing maintenance may have closed it. Do not use the utility's meter valve: Phoenix says that requires a special tool and you may be held responsible for repairs to a damaged meter.
- 3Check zone valves if only part of the building is out. Planning a shutdown explains why zones are labeled.
- 4Look for water where it should not be. EPA suggests watching for wet spots on sidewalks, in parking lots and in grassy areas around a facility. A sudden total loss with a soaked yard suggests a broken service line. How to tell.
- 5Check the meter. If the dial is spinning with every fixture closed, water is leaving upstream of your fixtures.
When should you call a plumber?
If the utility isn't affecting your area and the valves are open, the cause is inside your property. A leak that drained the line, a failed pressure regulator or a stuck valve each need someone to find it. If a boil-water or other advisory follows an outage, restoring service safely takes more than turning the valve on.
For a restaurant, losing water also raises food-safety questions that apply immediately; see the outage close and reopen page. HQ offers 24/7 emergency service if the cause turns out to be inside the building.