outfall       
noun [ C ] uk/ˈaʊt.fɔːl/ us/ˈaʊt.fɑːl/
 排水口;排污口
the place where water or liquid waste comes out of a pipe
  Damaged and blocked outfalls will cause surface water problems. 受损和堵塞的排污口将导致地表水问题。 
 Each day, the outfall pipe pumps 240 million gallons of waste water into the sea. 排水管每天将2.4亿加仑的废水排入大海。 
 - More examples
 - The flow from one outfall is discharged to the stream without treatment.
 - The feasibility studies found that submarine ocean outfalls would indeed solve the problem of beach pollution.
 - By the time the agency's emergency response team arrived at the plant, the stormwater outfalls that carry water off the property had been closed.