§ 50.07  CLASSIFICATION OF WATER PIPES AND MAINS.
   Water pipes or mains are classified as:
   SERVICE PIPE or MAIN.  One designed to supply water to the property abutting upon the particular street or way in which it is laid.
   SUPPLY PIPE or MAIN.  Any pipe, ditch, flume, conduit, or other appliance designed to conduct a supply of water from its source to the municipality.
   TRUNK PIPE.  One designed to supply water to the property abutting upon the street or way in which it is laid and to other pipes or mains in a defined district or portion of the municipality.
(SDCL § 9-47-8)