Water in an excavation: which pump do you need?
Dewatering an excavation, trench or foundation comes down to three things: how dirty the water is, how much there is, and how high or far you need to lift it. Get those right and the pump choice follows.
Three questions that pick the pump.
Dewatering comes down to how dirty the water is, how much there is, and how high you must lift it. Answer these and the right contractor pump follows.
How dirty is the water?
Most excavation water carries silt, sand and grit, which clogs or wears out a clean-water pump. You need a pump built for it:
- EVAK Trenchman: a built-in agitator keeps settled silt in suspension so it pumps away. The choice for muddy, sediment-heavy trenches.
- EVAK Drainox: a stainless steel vortex pump for hardwearing general site dewatering, available in 110V, 230V and 400V three phase.
- Tsurumi HS and Tsurumi LB: rugged contractor pumps for continuous site drainage, the reference standard on hire fleets.
How much water, and how high?
Match the flow rate (litres per minute) to how fast you need the excavation clear, and the head (metres) to how high or far you are pumping to discharge. For large volumes, see our high flow pumps; for deep lifts, our high head pumps.
What power is on site?
For construction sites, 110V is standard, and most of these pumps are available in 110V. 230V suits smaller or domestic jobs, and 400V three phase the largest continuous duties.
If there isn't any power, you can consider Engine Driven Pumps.
See the full dewatering pumps and site drainage and construction pumps ranges, or call our engineers on 0115 987 0358 to size a pump for your excavation.
Site dewatering, answered.
What pump do I need to dewater an excavation?
Most excavation water carries silt and grit, so you need a pump built for it. The EVAK Trenchman has a built-in agitator for sediment-heavy trenches; the EVAK Drainox, Tsurumi HS and Tsurumi LB are rugged contractor pumps for general site dewatering.
Can I use a clean-water pump to dewater a trench?
Not for long. Silt, sand and grit will clog or wear out a clean-water pump. Use a vortex, agitator or contractor site pump designed to pass and handle abrasive, sediment-laden water.
What power supply do site dewatering pumps use?
On construction sites 110V is standard and most of these pumps offer it. 230V suits smaller or domestic jobs, and 400V three phase is for the largest continuous duties.
