What type of valve do newer style curb stops use?

• A. Ball valves
• B. Gate valves
• C. Globe valves
• D. Butterfly valves

Answer: (A)

Ball valves are used in newer curb stops because they provide a quick, positive shut-off with minimal torque in a compact design. When you operate a curb stop with a key, you want a valve that can be turned a small amount (a quarter turn) to go from fully open to fully closed, and the ball valve achieves that with a simple rotation of the stem. The ball’s bore aligns with the flow when open and blocks it when closed, delivering reliable sealing even if the curb box has some dirt or debris. This makes it well-suited to the surface-access, service-line environment of curb stops.

Gate valves, by contrast, require multiple turns to move a gate up and down, which can be difficult to achieve in a curb box and increases the chance of sticking or seat damage from sediment. Globe valves are designed for throttling and typically demand more turning effort and space, which isn’t ideal in the confined curb-stop setting. Butterfly valves are larger and better suited for bigger mains, so they’re not common for small service-line curb stops.