The following words, terms and phrases, when used in this article, shall have the meanings ascribed to them in this section, except where the context clearly indicates a different meaning:
All sewer lines, lift stations, pumping facilities, septic tanks, sewer collection facilities and their appurtenances which the City owns or which are owned on behalf of the City by county, or which the City has possession of and/or operating responsibility for, whether owned by the City or not, together with all works, plants, instrumentalities and properties used or useful in connection therewith in collecting sewage and transmitting and conveying such collected sewage to sewage treatment facilities, and all extensions, enlargements and improvements thereto in the City.