Groundwater resource management during construction dewatering

The careful management of groundwater resources is critical in the design and implementation of construction dewatering systems. Such systems are typically required to temporarily lower the water table to a target level, in turn aiding construction. As is indicated in the name, ‘construction dewatering’ involves the removal or abstraction of groundwater over the period of the operation. This can impact on groundwater resources, with these impacts being amplified in recent years due to increasing strain on global groundwater supplies. In addition to placing strain on groundwater supplies through abstraction, construction dewatering operations also have the potential to impact negatively on groundwater resources through inducing contamination of an aquifer. This can lead to groundwater quality deterioration. In light of the potential risks, and in order to mitigate damage to groundwater resources during construction dewatering operations, hydrogeoethics must be considered from an early stage in a project. This in turn will lead to appropriate planning as to how the required groundwater abstraction can be managed to ensure the protection of groundwater as a resource. This paper documents some of the key groundwater resource risks to be considered during a construction dewatering operation. The paper then outlines how groundwater resources can be managed effectively during construction dewatering, from the planning stage right through to well decommissioning. A recent relevant case study is also presented.