Educational Diagram
How Your Home's Water Supply Works
Tap a part to learn what it does.
Overview
Water travels from the city main under the street, through a meter, through your service line, past the main shutoff, and into your home's distribution piping. Knowing this path — and where the shutoff is — is the most important thing a homeowner can learn about their plumbing.
How It Works
The utility water main supplies a service connection to the property. The meter measures usage, and the service line then feeds the building's shutoff, pressure-control equipment where applicable, and distribution piping. Ownership and repair responsibility around the meter and service connection can vary by utility, so verify the current serving-utility rules instead of assuming the meter is always the exact legal boundary.
Key Components
Water Meter
Measures water usage. Responsibility for piping and connections around the meter depends on the serving utility's rules and service agreement.
Service Line
The pipe from the meter to the house. Homeowner-owned in most Knoxville areas.
Main Shutoff Valve
Stops all water to the house. Usually near where the line enters.
PRV (where applicable)
Reduces street pressure to safe house pressure.
Distribution Piping
The pipes that branch to every fixture in the house.
Common Issues
No water at all
Main shutoff closed, frozen line, or utility issue.
Maintenance Tips
- Find and label your main shutoff before you need it.
- Know where your water meter is — it's the key to the meter leak test.
- If you have a PRV, know where it is (usually near the main shutoff).
- If leaving town for a week or more, consider shutting off the main water.