Infrastructure and site development projects that extend below the groundwater table present challenges for engineers and construction contractors. If groundwater is not adequately controlled then excavations may flood or become unstable, which can result in project delays and increased costs.
Dewatering assessments typically involve prediction of groundwater inflow rates and the amount of groundwater lowering near proposed excavations. The objective of a dewatering assessment is to inform decisions for groundwater control, to allow excavations to be constructed in suitably dry, stable and safe conditions, and to assess the potential for ground settlement outside excavations.
- Undertake or co-ordinate hydrogeological field testing
- Development of a hydrogeological conceptual model
- Groundwater numerical modelling
- Dewatering assessment to assess potential effects on the natural and built environment
- Examples of dewatering assessments include trenches, shafts, tunnels, and basement excavations
- Preparation of technical reports and Groundwater and Settlement Monitoring and Contingency Plans (GSMCP) to support resource consent applications.