What device is installed on the water service line that serves as a control valve in case the water supply needs to be cut off to a building?

The curb stop is specifically designed to control the flow of water in a service line, allowing for the water supply to be shut off when necessary, such as during maintenance or emergencies. It is typically located just before the water meter and is often accessible from the street or sidewalk. This accessibility makes it practical for municipal workers or property owners to quickly halt the water supply without needing to access the interior plumbing of a building.

While gate valves also serve as flow control mechanisms, they are usually found within the plumbing system of a building rather than on the service line itself. Check valves are employed to prevent backflow, ensuring that water flows in one direction only, and pressure regulators are used to control the pressure of the incoming water supply. Neither of these serves the same direct function of isolating the water service line as the curb stop does.