Whereas sewage treatment plants remove harmful bacteria and other contaminants from their effluent, storm water runoff is usually untreated.
Whereas sewage treatment plants remove harmful bacteria and other contaminants from their effluent, storm water runoff is usually untreated.
尽管污水处理厂会清除污水中的有害细菌及其他污染物，但是暴雨迳流通常是无法处理的。