noun
drainage; sewer system; ditch; gutter
Refers to the infrastructure for carrying away wastewater and rainwater, including pipes, ditches, and gutters.
この地域の下水は古くて、大雨のたびに溢れる。
The drainage in this area is old and overflows every time it rains heavily.
道路の下水が詰まっている。
The gutter on the road is clogged.
noun
sewage; black water
Refers to the wastewater itself, especially from toilets and kitchens. Often used in contexts like treatment, discharge, or pollution.
工場から出る下水は厳しく管理されている。
Sewage discharged from factories is strictly controlled.
下水を浄化して川に戻す。
We purify the sewage and return it to the river.