Groundwater control is one of the most common and complicated applications encountered on a construction site where excavation occurs below the water table or into water bearing soils. On sites with high groundwater tables, a dewatering system must be installed to pre-drain the site to facilitate excavation and footings construction.
Design professionals should consult with a geotechnical engineering firm to perform a hydrogeological study and to recommend an appropriate dewatering and discharge system specific to project needs.
A reputable dewatering professional will ensure a properly installed dewatering system accomplishes these objectives:
1.
Lowers the water table inside the excavation and intercepts seepage that emerges from the banks and the bottom of the excavation.
2.
Improves the stability of the bottom of the excavation to prevent disturbance due to hydrostatic pressure.
3.
Provides a reasonably dry working area in the bottom of the excavation
4.
Provides for the collection and removal of surface runoff water and rain-fill.
Once surfaces are water-free, design professionals face another challenge. Which waterproofing method best ensures a water-tight foundation, especially for blindside applications? We’ll tackle that question in our next blog.