A County Water Supply Authority shall not engage in any activity except the water supply business. All waterworks, water supply works and water distribution systems, heretofore or hereafter acquired, held, constructed, improved, maintained and operated, owned or leased either in the capacity of lessor or lessee, by a County Water Supply Authority, shall constitute a single project for all the purposes of this act and the act to which this act is a supplement.
16 P.S. § 12904