Rhode Island Journeyman Plumber Practice Exam 2026 - Free Journeyman Plumber Practice Questions and Study Guide

The minimum clearance required above a sewer line for a water line is specified to ensure the safety and integrity of the water supply. A clearance of 12 inches is mandated because this distance helps to prevent contamination of the potable water supply. In instances where there is a break or leak in the sewer line, maintaining this vertical separation reduces the risk that wastewater could seep into the water line, thereby protecting public health and ensuring compliance with plumbing codes and regulations.

This requirement reflects a broader principle in plumbing where different types of piping systems must maintain certain clearances to ensure safe and reliable operation. Adhering to this standard minimizes the possibility of cross-contamination between water and sewage systems, which is essential for preventing health hazards associated with untreated sewage entering the drinking water supply.