Journeyman Plumber ExamWater Supply SystemsEasy
A plumber is installing a water service line from a municipal main to a new commercial building. The building's water demand requires a 2-inch diameter service line. What is the minimum burial depth required for this water service pipe in an area where the frost line is 30 inches deep, assuming local code mandates a minimum of 6 inches below the frost line?
- A36 inches
- B42 inches
- C24 inches
- D30 inches
Show answer & explanationAnswer & explanation
Correct answer: A. 36 inches
The minimum burial depth for a water service pipe is determined by the frost line depth plus any additional code requirements. In this case, 30 inches (frost line) + 6 inches (code mandate below frost line) = 36 inches.
Why the other options are wrong
- B. This depth exceeds the minimum requirement, which is permissible but not the 'minimum' required.
- C. This depth is less than the frost line, risking freezing.
- D. This depth is only at the frost line, not below it as required by code.
Water Service Burial Depth
Water service pipes must be buried below the local frost line to prevent freezing, with additional depth often mandated by plumbing codes.
- Prevents freezing of water in the pipe.
- Based on local climate and geological conditions (frost line).
- Local plumbing codes often specify a minimum depth below the frost line.
Memory trick: Deeper than the freeze, your water flows with ease.