PVC pipe is quite often used for underground piping, including in drainage, irrigation and water supply systems. PVC pipe is strong and durable, and it is resistant to rot and moisture. Of course, it is crucial to check local codes.
Since PVC pipe is durable and resistant to rot, electrical wiring is often pulled through PVC conduit pipes laid underground. Quite often PVC pipe stubs can be seen protruding from new concrete slabs at construction sites, which might include electrical conduits, drainage and supply piping.
PVC pipe is sometimes used for underground drainage systems, although ABS plastic pipe is probably more popular now. ABS costs less and provides similar benefits. PVC pipe is more common in industry because it is stronger and more durable than ABS and some of the other plastics.
PVC is often used as underground water supply piping to bring pumped water from the well to the house. Generally, this type is flexible PVC that connects with special fittings and band clamps, making installation quick and easy, yet secure enough to be buried underground for years.
Recent and emerging data regarding some PVC plastics and some of the components (primarily "phthalates") used to manufacture them have raised questions about the safety of using phthalate-containing PVC piping on potable water systems. It is thought these chemicals may leach into the water from the piping, given the right conditions. Phthalates have been linked with certain health issues.