#sewer_main__sewermain__sewer_line__sewerline  a main in a sewage system
  supertype:  main  a principal pipe in a system that distributes water or gas or electricity or that collects sewage
  part of:  sewage_system__sewer_system__sewersystem__sewage_works  facility consisting of a system of sewers for carrying off liquid and solid sewage
     part of:  infrastructure__base  the stock of basic facilities and capital equipment needed for the functioning of a country or area; "the industrial base of Japan"

No statement uses or specializes sewer_main; click here to add one.