Global Pump submersible dewatering pumps are centrifugal in type and are used to remove water collected in construction sites, tunnels, and mines. They suck the dirty water – which is circulated in the casing by the impeller and later discharged to a wellpoint system or open sump. Depending on the type of water, a dewatering pump may use strainers to remove abrasives from the groundwater before being processed. A dewatering sludge pump, on the other hand, is used for moving thick, viscous fluids.