Construction Dewatering Methods and Processes


Engineers often must manage groundwater on various building sites, particularly for the construction of a basement or foundation. To guarantee that the project is a success, groundwater should be managed efficiently. Construction dewatering is a process that extracts surface water and subsurface water from the construction site in order to provide a steady and secure subgrade. Therefore, whether a minimal amount of water needs to be taken away or a large amount of water needs to be regulated in deep excavations, a range of techniques should be considered to make sure all safety measures have been followed.

The importance of dewatering your construction site

One of the most important things for a construction team is effectively preparing the site for work. Here are some reasons why dewatering is important:

  • Prepares the soil for construction. The soil’s elements are an essential factor for construction. Before starting a construction project, you should be sure you are able to build a sturdy structure on the site because working with wet soil is quite difficult.
  • It prevents unsafe conditions. It is important to maintain safety on construction sites; employees don’t like working in wet conditions, including excavation workers, pipeline welders, and every other constructor. Additionally, dry excavations reduce slip and trip hazards and prevent equipment damage by preventing slipping and tripping hazards. Every construction site should be kept safe and free from any health risks. Dewatering reduces the accidents that could occur on a construction site. Additionally, dewatering removes toxins and waste from the water, allowing your team to reuse it for other purposes. Removing the groundwater from the site reduces employee exposure to toxins if it is contaminated with chemicals from a dry cleaner or leaking fuel storage tanks.
  • It ensures the project is completed on time. During the rainy season, a construction site could get flooded, which could delay the project completion time frame. Also, excess groundwater can damage equipment which could lead to costly repairs.

Methods of dewatering

  • Open Sump Pumping. Open sumping is a series of trenches, small pits, or depressions in the construction site. It is the simplest and cheapest dewatering method and works well for most soil and rock conditions. Groundwater is collected by drains and conveyed into sump tanks. The water is continuously evacuated from the sump (manually or mechanically). The groundwater collects in the sump and is discharged through a discharge pipe by a pump.
  • Well Point System. This is one of the most common dewatering options. This method’s installation is easy, relatively flexible, practical, and effective under most soil and hydrologic conditions. Well points are connected to a surface-mounted vacuum-assisted centrifugal pump, which draws water up the header to a discharge point through an above-ground header.
  • Constructing Deep Wells. If deep excavation is required to remove a large amount of groundwater, deep wells may be constructed in soils or rocks with moderate permeability (e.g. sands) to high permeability (e.g. gravels). Dewatering systems remove groundwater from the construction site through drilled gravity wells.
  • Educator System. This is a specialized technique used in low-permeability soils such as silts and clay. Educators are commonly used to help stabilize the side slopes and soil in the excavation area. Pumps in the educator are in the well’s bottom and do not move down-hole.

Things to consider when choosing a dewatering method

The accomplishment of your building venture will frequently be dictated by the dewatering technique you pick. You can allude to the geotechnical and groundwater webpage examinations and hazard evaluations that have been finished as a feature of the building venture and, if necessary, counsel the data given by the nearby powers. Regularly, you will require master designing administrations to deal with soil balance and fruitful groundwater control. The typical strategy for dewatering incorporates the accompanying advances: gathering water, siphoning, sifting/expulsion of silt, and release.

Final words

A variety of approaches are available to extract ground water from building sites, forming a dry, secure workspace for people working onsite. Keeping the worksite dry makes it easier to do the construction work quickly and without lags in the plan. Those involved in the construction industry must be aware of relevant laws and regulations and be able to undertake all phases of the project – from demolition to repair – to be successful in a situation where more and more structures are being developed and designed.

If you are uncertain about the method of dewatering to utilize, you should consult a professional. Meridian environmental supplies a wide variety of environmental services. Our group of proficient experts have access to the most up-to-date technology and techniques and will make sure your construction project progresses smoothly.