Identify the maximum depth for an underground service pipe.

• A. 1000mm
• B. 1250mm
• C. 1350mm
• D. 1500mm

Answer: (C)

The limit on how deep an underground service pipe can be laid is set to balance protection with practicality. You want enough cover to protect the pipe from surface damage, freezing, and future disturbances, but not so deep that locating, digging, or servicing the pipe becomes impractical and costly. In this subject, the commonly accepted maximum depth for a domestic cold-water service is about 1.35 meters below ground level. At this depth, the pipe is well protected from typical surface activities and frost risks, yet still within a reasonable reach for maintenance work and connections. Going deeper adds unnecessary digging challenges and costs, while shallower depths raise the risk of damage from gardening, vehicles, or other surface actions. That combination makes 1.35 meters the best choice.