One of our many disciplines is vertical dewatering. Vertical dewatering is accomplished by connecting vertical filters to a central loop and a vacuum-piston pump. There are various systems for vertical dewatering. Vacuum and gravitational filters are most commonly used.
Vacuum filters are partially perforated filters with a length ranging from 4 up to 7 meters. The filters are sprayed by hand or machine in a combined drilling/rinsing process.
Application: Vacuum filters are used in sandy soils for small and short term construction projects such as sewage pipes up to a depth of 5 metres.
Gravitational filters rely solely on gravitation for the flow of water to the filter. By means of a drilling machine, possibly equipped with a rinsing device or hollow auger (dry drilling), filters are vertically inserted into the ground. These filters can have a length of up to 9 meters. This filter consists of a tube wrapped with coconut fibre. In this tube another tube, connected to the centralized suction tube is inserted. It is called Koop Mini Well
Application: Gravitational filters are used in multi-layered soils or in soils where vertical filters cannot reach the required depth.