#sewage_system__sewer_system__sewersystem__sewage_works  facility consisting of a system of sewers for carrying off liquid and solid sewage
  supertype:  installation__facility  a building or place that provides a particular service or is used for a particular industry; "the assembly plant is an enormous facility"
  part:  sewerage  sewer_main
  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"

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