We frequently uncover challenges controlling excessive amounts of water while excavating the construction projects or infrastructure development. With lower water table and the bedrock or soils is permeable, this type of problem arises.

These large water volumes would usually be unanticipated, and they are often left for the contractor to cope with. This can harm schedules and finances, along with complicating routine building site administration. Eventually, poor waterproofing membrane installation beneath the foundation, for example, can degrade construction quality. A system for dewatering may be required in some circumstances to lower the water table permanently. This difficult scenario can be readily resolved upstream by including a thorough and suitable hydrogeological component in the preliminary environmental and geotechnical assessments. The etude hydrogéologique component of such types of research is frequently overlooked, resulting in a crude precision of the depth of the water table.

Using hydrogeology

The hydrogeological element, in particular, is designed to determine vital hydrogeological and geological conditions, such as:

• Existing geological description of bedrock and soils
• A measure of the water table’s depth
• The direction of groundwater flow and the hydraulic gradient
• Current soil and bedrock hydraulic permeability or conductivity
• The requirement to regulate the groundwater quality

During the study, the below-mentioned activities are carried out on-site to achieve this:

• The observation wells drilling and installation
• Survey of Piezometric level
• Test for Hydraulic conductivity
• Sampling for groundwater

If the bedrock and soils are extremely porous, a more thorough investigation, including pumping experiments and wells, may be necessary. Obtaining this information and identifying the vital hydrogeological parameters while the excavation phase aids in anticipating groundwater infiltration issues.

The below-mentioned factors are examined in detail:

• Calculation of groundwater flow and volume determined on the reachable depths or the completed excavation phase
• Methods for competent excavation and drainage dewatering are being developed, such as:
• At the base of the excavation, there is a sump pump system.
• Well points at the edge
• wells pumping
• Helps determine if a membrane for waterproofing needs to be put beneath the foundation.
• Groundwater discharge is managed dependent on the quality.
• Comprehensive design of lasting dewatering/drainage system after digging and infrastructure construction:
• Drainage system sizing and designing under infrastructure and margins
• Design of a pumping well-based drawdown water table system

Numerical modeling of groundwater flow is one tool that can be used for optimizing dewatering strategies along with designs of the drainage system. Hydrogeologists can use these technologies to predict optimization of the dewatering systems or water flows properly.