Final answer:
The minimum distance that a potable water line has to be above a sewer line is typically around 18 inches. This helps prevent contamination between the two systems.
Step-by-step explanation:
The minimum distance that a potable water line has to be above a sewer line can vary depending on local regulations and codes. However, a common guideline is that the potable water line should be placed at least 18 inches above the top of the sewer line. This distance helps to prevent any potential contamination of the water supply with sewage or other harmful substances.
By maintaining a minimum distance between the potable water line and the sewer line, the risk of cross-contamination is minimized. Any accidental leaks or breaks in the sewer line would be less likely to affect the potable water supply if there is a sufficient vertical distance between the two.
It is worth noting that local regulations and codes may have specific requirements for this minimum distance, so it is essential to consult with local authorities and adhere to their guidelines when installing potable water and sewer lines.