What is the term used for the distribution of underground pipes in a water supply system?

The distribution of underground pipes in a water supply system is referred to as water mains. Water mains are large pipes that transport potable water from the treatment facility or water source directly to residential and commercial areas. They are crucial for delivering water under pressure and ensure that communities have uninterrupted access to clean water. The design and construction of water mains are fundamental to the infrastructure of a water supply system, as they need to be durable and able to withstand environmental conditions and water pressures.

Sewers, while also a type of underground piping system, are specifically designed for transporting wastewater and stormwater, rather than potable water. Manifolds are typically used to distribute fluids in various applications, including plumbing, but do not specifically refer to a water supply system's main distribution lines. Ducts usually pertain to systems that transport air or other gases, making them irrelevant in the context of water supply systems. Thus, the term water mains distinctly identifies the specific underground pipes that are part of a water distribution network.