洞とう道どう

noun

service tunnel; utility tunnel

Technical term for an underground tunnel housing utility lines such as cables, gas pipes, or water mains. Primarily used in civil engineering and infrastructure contexts.

• この洞とう道どうには高こう圧あつケーブルが敷ふ設せつされている。

  High-voltage cables are laid in this service tunnel.

• ガス管かんを洞とう道どう内ないに収しゅう容ようする計けい画かくだ。

  There is a plan to house gas pipes inside the utility tunnel.