How many inches above sewer lines should water mains ideally be located?

The ideal placement of water mains above sewer lines is 18 inches. This distance is crucial for several reasons, primarily focusing on public health and safety, as well as system integrity. Keeping water mains 18 inches above sewer lines helps to prevent any potential contamination of drinking water. In the event of a leak or rupture in the sewer line, the vertical separation creates a buffer zone that reduces the risk of sewage contaminating the potable water supply.

Additionally, this separation helps to ensure that any maintenance, repairs, or inspections can be conducted without compromising either line, thereby promoting the resilience and reliability of both water and sewage infrastructure. Moreover, this distance is a standard set forth in various plumbing codes and regulations to maintain sanitary conditions and safeguard public health, reflecting best practices in utility management.