Groundwater
The term 'groundwater' refers to all water which is below the surface of the ground and within the permanently saturated zone. A groundwater body is a distinct volume of groundwater within an aquifer. The term ‘hydrogeology’ refers to the nature, distribution and movement of groundwater in soils and rocks, including in aquifers. Ref The HS2 London-West Midlands Environmental Statement, Glossary of terms and list of abbreviations, DETR 2013.
Groundwater is an important part of the water cycle which continually moves water through the environment. Water evaporates from the oceans and condenses into clouds, before falling onto land as rain and flowing into rivers and back into the oceans.
However, the ground has the potential to interrupt this cycle, absorbing rainwater like a sponge. Some of this water will return to the atmosphere through processes such as transpiration, while some will infiltrate deeper into the ground where it becomes groundwater.
The water table is the level at which the ground becomes saturated and water will flow to a point of discharge such as a spring, lake, river or sea. Groundwater plays a vital role in supporting industry, wells, wetlands, stream flows, and so on. The water table may rise during periods of heavy rain or melting snow, or fall during drier periods, or as a result of extraction.
In some parts of the world, water shortages can be experienced when groundwater supplies are used faster than they are replenished, while in other regions, groundwater can cause flooding or can become polluted by human activities such as industry and agriculture.
Nearly 30% of global freshwater originates from groundwater, and almost all the water used for agriculture, industry and drinking will have been groundwater at some point in its cycle.
Some geological formations are impermeable to groundwater whilst others are permeable. Permeable formations – known as aquifers – have fine holes or networks of fine cracks that allow water to flow through them. The size of the spaces in the soil or rock, as well as how well they are connected, determines the speed of groundwater flow.
In the UK, hydrogeologists are work to ensure groundwater is maintained in sufficient supply with a quality that is protected. In developing countries, hydrogeologists may work on rural water supply projects to help provide safe and accessible water.
Notes:
- Groundwater-dependent terrestrial ecosystems are wetlands that are directly dependent on water from a groundwater body to maintain their form and function.
- Groundwater source protection zones are areas defined by the Environment Agency which show the risk from contamination/pollution to groundwater that is extracted for drinking water.
- According to the Groundwater Foundation, groundwater (or ground water) is ‘…water found underground in the cracks and spaces in soil, sand and rock. It is stored in and moves slowly through geologic formations of soil, sand and rocks called aquifers.’ Ref https://www.groundwater.org/get-informed/basics/whatis.html
- The unsaturated zone is: ‘The soil layer between the land surface and the groundwater level.’ Ref The SuDS Manual (C753), published by CIRIA in 2015.
- A groundwater body is: 'The principle reporting units for distinct volumes of groundwater within an aquifer or aquifers defined by the Water Framework Directive.’ Containment systems for the prevention of pollution, Secondary, tertiary and other measures for industrial and commercial premises (CIRIA C736), published by CIRIA in 2014.
- Approved document C: Site preparation and resistance to contaminants and moisture, 2004 edition incorporating 2010 and 2013 amendments defines groundwater as: ‘Water in liquid form, either as a static water table or flowing through the ground.’
[edit] Related articles on Designing Buildings
- Chalk aquifer.
- Dowsing.
- Flood.
- Groundwater control.
- Groundwater control in urban areas.
- Groundwater flooding.
- Groundwater recharge.
- Groundwater source protection zone.
- Pumps and dewatering equipment.
- Raising awareness of dewatering regulation.
- River engineering.
- Types of water.
- Water engineering.
- Waterlogged.
- Water table.
Featured articles and news
Construction Skills Mission Board launch sector drive
Newly formed government and industry collaboration set strategy for recruiting an additional 100,000 construction workers a year.
New Architects Code comes into effect in September 2025
ARB Architects Code of Conduct and Practice available with ongoing consultation regarding guidance.
Welsh Skills Body (Medr) launches ambitious plan
The new skills body brings together funding and regulation of tertiary education and research for the devolved nation.
Paul Gandy FCIOB announced as next CIOB President
Former Tilbury Douglas CEO takes helm.
UK Infrastructure: A 10 Year Strategy. In brief with reactions
With the National Infrastructure and Service Transformation Authority (NISTA).
Ebenezer Howard: inventor of the garden city. Book review.
The Grenfell Tower fire, eight years on
A time to pause and reflect as Dubai tower block fire reported just before anniversary.
Airtightness Topic Guide BSRIA TG 27/2025
Explaining the basics of airtightness, what it is, why it's important, when it's required and how it's carried out.
Construction contract awards hit lowest point of 2025
Plummeting for second consecutive month, intensifying concerns for housing and infrastructure goals.
Understanding Mental Health in the Built Environment 2025
Examining the state of mental health in construction, shedding light on levels of stress, anxiety and depression.
The benefits of engaging with insulation manufacturers
When considering ground floor constructions.
Lighting Industry endorses Blueprint for Electrification
The Lighting Industry Association fully supports the ECA Blueprint as a timely, urgent call to action.
BSRIA Sentinel Clerk of Works Training Case Study
Strengthening expertise to enhance service delivery with integrated cutting-edge industry knowledge.
Impact report from the Supply Chain Sustainability School
Free sustainability skills, training and support delivered to thousands of UK companies to help cut carbon.
The Building Safety Forum at the Installershow 2025
With speakers confirmed for 24 June as part of Building Safety Week.
The UK’s largest air pollution campaign.
Future Homes Standard, now includes solar, but what else?
Will the new standard, due to in the Autumn, go far enough in terms of performance ?
BSRIA Briefing: Cleaner Air, Better tomorrow
A look back at issues relating to inside and outside air quality, discussed during the BSRIA briefing in 2023.
Restoring Abbotsford's hothouse
Bringing the writer Walter Scott's garden to life.
Reflections on the spending review with CIAT.