渠 - ditch, canal, lock

leaving the (repair) dock

open ditch; open channel; open conduit; open culvert

open ditch

entering a dock

pipe (e.g. sewer, storm water); culvert

sewage pipe

chief of bandits

waterway; canal; river

drain with an oblong cross-section

underdrainage

combined sewer

subterranean drain; culvert; conduit