drain pit meaning in English

排放池
排水坑

Strategies for draining pit water during construction of the second - stage cofferdam of the three gorges project
三峡工程泄洪坝段蓄水初期实测渗流性态分析
Fire water drain pit is provided at side of bottom of each fire elevator well , waste water will be sucked up and drained out by the pumps
在每个消防电梯井底旁设有消防排水坑,废水经潜污泵提升排至室外