Dewatering is the process of removing water from the ground before carrying out a major project on the site. It is used for various sites, but it is most common in construction, and it is a necessary step for excellent operations on these sites. This article will highlight the various dewatering services in use today and some expert tips for extracting groundwater.
Reasons for Dewatering Prior to Construction
The main reason for dewatering sites before construction is to remove the excess water from the soil of the area to be excavated. Hence, making the site safe for workers and facilitating a smoother construction process. Here are other significant reasons to dewater before construction.
- Prevents sand boiling
- Helps to avoid basement floatation
- Helps to give construction workers stability on site
- Promotes stronger structures
- Prevents erosion
Dewatering Techniques for Construction
Several methods of dewatering have been introduced for different purposes, but only four techniques are recognised for construction.
- Wellpoint dewatering
- Eductor wells
- Sump pumping
- Deep wellpoint
- Wellpoint Dewatering: This is one of the most popular dewatering systems for construction. It involves the alignment of wells around the excavated area. Wellpoints are installed and connected via flexbows to the manifold and pump.
- Eductor Wells: The eductor well system of dewatering is similar to the wellpoint method, with the only significant difference being the item used for extraction. This setting of the wells is the same, but the system utilises high pressure/flow water through a venturi to create a vacuum. Motive and recovered ground water flows to the surface and discharged to the designated discharge point.
- Sump Pump: Sump pumping is the most used dewatering method for several reasons. Firstly, it is a very economical solution to eliminating groundwater. It is also a versatile dewatering technique that can be used for almost any project. In this method, the water is gathered in sumps at the excavation depth, where it is then pumped out.
- Deep Wellpoint: This dewatering technique is often adopted for projects and constructions where a large amount of water needs to be extracted from the ground. This method uses boreholes and water pumps lowered below the excavation depth. Wells are drilled along the excavated area, allowing the groundwater to fall freely into the wells. The pumps are then used to pressure the water away from the well to the collection point.
Tips for Dewatering
Dewatering can be a critical step before construction, especially in water-logged areas. But it is only valid when it is correctly carried out. Here are some expert dewatering tips to help you get it right.
- It is essential to evaluate the proper discharge area
- Ensure you get rid of contaminated water correctly
- Properly analyse soil reports including depth of the standing water table before selecting a dewatering plan.
Dewatering a construction site is advantageous, but the benefits can only be achieved when the process is carried out correctly. Knowing the suitable method to use is essential for getting excellent results, and the various dewatering methods have been highlighted in this article. To ensure best results, all dewatering work must only be completed using premium quality dewatering equipment and accessories.