Range of application of pumped groundwater-control methods in soils

Temporary control of groundwater is required for excavations, tunnels or shafts that extend below groundwater level. It is typically needed early in the construction programme and any shortcomings in the groundwater control strategy will likely lead to delay, cost overrun and occasionally catastrophic failure. In appropriate hydrogeological settings, pumped groundwater-control strategies offer a relatively quick, low-cost and low carbon dioxide footprint solution. The variety of techniques and construction methodology and the very wide range of hydrogeological settings mean that the design of pumped groundwater-control (dewatering) systems is not readily codified. Also, pumped groundwater-control systems and other groundwater control strategies are increasingly subject to environmental regulation and legislative oversight. This had led to reliance on experienced specialist contractors, designers and operatives to deliver groundwater control services. However, there remains a need for general construction practitioners to have access to up-to-date information on the range of strategies available together with their attributes, limits of application and associated risks. This paper uses recent experience to review and update existing guidance on the application of pumped groundwater-control systems in a variety of hydrogeological settings.