Well points are essentially shallow wells, which offer an economic and versatile method of groundwater control. Their close spacing and use of vacuum is particularly effective in stratified and fine graded soils.
Well points consist of small-diameter tubes with slots near the bottom that are inserted into the ground from which water is drawn by a vacuum generated by a dewatering pump.
Well points are typically installed at close centers in a line along or around the edge of an excavation. As a vacuum is limited to 0 bar, the height to which water can be drawn is limited to approximately 6 meters.
To enable functionality at greater depths, well points can be installed in stages, with the first stage reducing the water level by up to five meters, and a second stage, installed at a lower level, lowering the water level further.