What is the purpose of poly-pigging a water main?

Poly-pigging is a process used primarily for cleaning and maintaining water mains. The term refers to using a device known as a "pig," which is inserted into the water main to perform various tasks. The main purpose of poly-pigging is to clean the interior surfaces of the water pipe, which can accumulate sediment, biofilms, and other debris over time.

The process can also help to remove any buildup that may affect water quality and flow. While the specific aim of poly-pigging does not include sealing the inside of the main with a smooth coating or disinfecting it, successful cleaning can indirectly contribute to improved water quality. However, using pigging techniques should not be confused with actual disinfecting processes, which typically involve chlorine or other disinfectants.

Thus, the answer correctly indicates that the purpose of poly-pigging does not encompass sealing or disinfecting the water main, focusing solely on cleaning it.