Operator terms · Water

What is a water service line?

A service line is the small pipe that carries water from the main in the street to a single customer's building and meter. It is the last stretch of the distribution system, connecting one property to the public supply, and it usually has a curb stop to shut it off.

Last reviewed 2026-08-03

Where it fits

The main runs down the street; the service line taps off it and runs to one building. It typically passes through a curb stop near the property line and a meter, then into the customer's plumbing.

Why it matters

Because the service line is the direct link to a customer, a leak or a cross-connection on it can affect both that customer and, through backflow, the public supply. The curb stop lets an operator isolate it.

Common questions

What does a service line connect?
The water main to one customer's meter and building.
What valve shuts off a service line?
The curb stop near the property line.
Is the service line part of the distribution system?
Yes; it is the last connection to a single property.

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