Well Point Dewatering Systems & Their Use in Construction

The installation of a well point system is used to help lower the groundwater levels of a construction site and create a stable working environment. They usually consist of a series of small diameter wells connected to a well point pump by a header pipe. A well point is normally placed around an excavation site in most circumstances. The pump’s purpose is to help draw water from the ground to the surface by creating a vacuum in the header pipe.

Installing a well point system is just one technique available to engineers, to help make a workplace more favourable for construction purposes. This is particularly important if a project is to be carried out in an area with a high volume of water beneath the earth. This type of dewatering system is commonly used around or besides excavation sites. Water can be drawn from wells up to 6 metres underground. When the depth level is deeper, however, the best way to obtain optimal dewatering results is to establish well points at various intervals as the excavation progresses.

Well point systems come in a variety of shapes and sizes.

1) Well Point System with a Single Stage

A pipe measuring roughly 1.5 metres in length and 55 millimetres in diameter is used in this well point system. Because of the nature of the installation, it is recommended that the holes be covered with a screen to prevent the pipe from clogging. A jetting nozzle serves as a driving point at the bottom of the well. A ball valve near the bottom end of the single-stage well point system, which serves as a conduit for water to flow in one direction, is installed during the installation procedure.

The well point at the bottom is connected to a riser pipe with the same diameter measurement. A horizontal pipe known as the header pipe connects the riser pipes and the pumping machine. During the installation, the riser pipes give space for water to flow downhill at a specified depth.

As a result, the installed pump’s job is to keep the water level in check until the installation is finished.

2) Well Point System with Multiple Stages

For excavations larger than 4.5m or in sloping locations, a multi-stage well point system is recommended. The multi-stage system, unlike the single-stage well point system, is installed in stages. The well point is installed at a depth of 4.6 metres during the first installation step. It will be in use until the water table rises over the 4.6 m mark. The surrounding surroundings will be dug before the second installation is installed. It will be the location where the second well point will be installed. Furthermore, new well points are erected, so long as the water table remains below 4.6 metres.

The use of well point systems

The following construction location can benefit from well point systems:

• constructing subsurface storage tanks
• constructing a bridge
• Building foundation excavation
• Basement construction is a type of construction that involves the construction of a basement.
• constructing deep sewer lines
• Construction of a subway
• Tunnel construction

The final word

Dewatering for shallow foundations and excavation sites is a much easier task when well point systems are used. It’s relatively easy to set up and maintain. It’s available in single-stage and multi-stage versions, making it adaptable to a wide variety of construction locations and conditions.