Where storm sewers are separated from sanitary sewers, runoff enters receiving waters untreated and can carry a variety of wastes, including organic and toxic wastes.

• 在雨水沟与污水道分开的地方，街道雨水没经过处理并携带各种各样的废物，其中包括一些有机的和有毒的废品流人承接河道。