sanitary sewer

例句：

1. 1. The city's sewage system is designed to handle the waste from thousands of homes and businesses.
   城市的污水处理系统设计用来处理成千上万家庭和企业产生的废水。
2. 2.The sewer was clogged with garbage, causing a backup that flooded the streets.
   下水道被垃圾堵塞，导致污水倒灌，淹没了街道。
3. 3. The construction workers were required to wear masks and gloves while working in the sanitary sewer.
   施工工人在卫生下水道工作时必须佩戴口罩和手套。