Dewatering construction sites
Dewatering refers to the removal of groundwater and/or surface water from a site before construction work commences. This may be necessary on sites where there are trenches and excavations in which water can accumulate, in places where there is an inadequate slope for water run-off, or where there is a high water table.
Dewatering techniques typically include pumping and evaporation and may include the use of:
For more information, see Dewatering equipment.
Care should be taken when pumping to ensure water is being discharged somewhere suitable, otherwise erosion and other problems can occur. Best management practices must be followed when pumping water to lakes, wetlands or directly into storm sewers.
NB The SuDS Manual published by CIRIA in 2015 defines de-watering as: ‘The lowering of groundwater/surface water levels or the removal of water from a substance.’
Culvert, screen and outfall manual, (CIRIA C786) published by CIRIA in 2019, defines dewatering as: ‘The process of handling and/or reducing significant flows of water (especially groundwater) into an area where construction work is being undertaken.’
Short Guide, Lime Mortars in Traditional Buildings, published on 1 March 2013 by Historic Scotland, defines dewatering as: ‘The rapid loss of water that occurs when a mortar is applied to a porous substrate on which suction has not been controlled by dampening down.’
[edit] Related articles on Designing Buildings
- Freezing method.
- Geotechnical engineering.
- Ground conditions.
- Ground investigation.
- Groundwater control.
- Groundwater control in urban areas.
- Hydrogeological Impact Appraisal HIA.
- Passive dewatering.
- Pumps and dewatering equipment.
- Raising awareness of dewatering regulation.
- Sinkholes.
- Sludge.
- Soakaway.
- Sustainable urban drainage systems SUDS.
- Water abstraction licence.
- Water engineering.
Featured articles and news
Future Homes Standard Essentials launched
Future Homes Hub launches new campaign to help the homebuilding sector prepare for the implementation of new building standards.
Building Safety recap February, 2026
Our regular run-down of key building safety related events of the month.
Planning reform: draft NPPF and industry responses.
Last chance to comment on proposed changes to the NPPF.
A Regency palace of colour and sensation. Book review.
Delayed, derailed and devalued
How the UK’s planning crisis is undermining British manufacturing.
How much does it cost to build a house?
A brief run down of key considerations from a London based practice.
The need for a National construction careers campaign
Highlighted by CIOB to cut unemployment, reduce skills gap and deliver on housing and infrastructure ambitions.
AI-Driven automation; reducing time, enhancing compliance
Sustainability; not just compliance but rethinking design, material selection, and the supply chains to support them.
Climate Resilience and Adaptation In the Built Environment
New CIOB Technical Information Sheet by Colin Booth, Professor of Smart and Sustainable Infrastructure.
Turning Enquiries into Profitable Construction Projects
Founder of Develop Coaching and author of Building Your Future; Greg Wilkes shares his insights.
IHBC Signpost: Poetry from concrete
Scotland’s fascinating historic concrete and brutalist architecture with the Engine Shed.
Demonstrating that apprenticeships work for business, people and Scotland’s economy.
Scottish parents prioritise construction and apprenticeships
CIOB data released for Scottish Apprenticeship Week shows construction as top potential career path.
From a Green to a White Paper and the proposal of a General Safety Requirement for construction products.
Creativity, conservation and craft at Barley Studio. Book review.
The challenge as PFI agreements come to an end
How construction deals with inherited assets built under long-term contracts.
Skills plan for engineering and building services
Comprehensive industry report highlights persistent skills challenges across the sector.
Choosing the right design team for a D&B Contract
An architect explains the nature and needs of working within this common procurement route.
Statement from the Interim Chief Construction Advisor
Thouria Istephan; Architect and inquiry panel member outlines ongoing work, priorities and next steps.
























