When used in this division, the following words and phrases shall have the following meanings, respectively, unless the context clearly indicates otherwise:
(1) WATER SYSTEM. A waterworks plant and distribution system, together with all appurtenances thereto and all property used in connection therewith, including franchises.
(2) SEWER SYSTEM. A sanitary sewer system, including mains, laterals, sewage disposal plants or sewage treatment plants, and all appurtenances to such system and all property used in connection therewith.
(3) SYSTEM. A water system or a sewer system.
(4) SYSTEMS. A water system and a sewer system.