(a.1) Water authorities and sewer authorities.--If a water or sewer authority incorporated by one municipality provides water or sewer services to residents in at least two counties and has water or sewer projects in more than two counties where the combined population of the served municipalities, excluding the incorporating municipality, is at least five times the population of the incorporating municipality, all of the following apply:
(g) Definitions.--As used in this section, the following words and phrases shall have the meanings given to them in this subsection unless the context clearly indicates otherwise:
"Water or sewer authority." An authority incorporated by a city of the third class, a borough, a town or a township to provide water or sewer services.
"Water or sewer project." Any pumping station, filtering plant, impoundment facility, dam, spillway or reservoir.
53 Pa.C.S. § 5610