Figure 2.
The multi-panel labelled A and B depicts sump pump drainage methods in excavations. Panel A shows sump pumps installed at the base of sloped excavation sides, with French drains directing water towards the pumps. Panel B shows pumped wells positioned outside the excavation, drawing groundwater away through connecting pipes. The diagrams illustrate groundwater collection at low points and removal using pumps, with arrows indicating water movement towards drainage points and wells.Groundwater control by (a) open pumping or (b) pre-drainage (from Cashman and Preene (2021), with permission)