"Underground pipes" refers to a system of pipes that are located below the surface of the ground. These pipes are used to transport things like water, sewage, or gas from one place to another without them being visible. Full definition
Includes underground piping and wiring, permanent connections, valves or attached devices on your property. (armourinsurance.ca)
A common culprit for water loss is caused by leaks from broken or aging underground pipes. (suncommunitynews.com)
A flush toilet needs a sophisticated set of underground pipes linking it to a facility that can digest its output — a sewage plant that cleans the water, releasing it back into the rivers and oceans, and re-processes the so - called biosolids into fertilizer safe to put onto fields. (thenextweb.com)