drainage
/ˈdreɪnɪʤ/
emptying something accomplished by allowing liquid to run out of it
中文释义：排水；排水系统
Proper drainage is essential to prevent flooding in urban areas.
良好的排水系统对于防止城市内涝至关重要。
The drainage of the swamp made the land suitable for farming.
沼泽地的排水使土地适合耕种。