counterdrain

例句：

1. 1. The engineer designed a counterdrain to prevent water from seeping into the foundation.
   工程师设计了一个逆流排水系统，以防止水渗入地基。
2. 2.The construction of this underground tunnel was crucial for counterdraining the city's sewage.
   建造这个地下隧道对于城市排污至关重要。
3. 3.The counterdrain system effectively reduced the amount of pollutants in the river, improving its quality.
   逆流排水系统有效地减少了河流中的污染物，提高了水质。