Aquifer
An aquifer is a geological formation that is sufficiently porous and permeable to store and yield a significant quantity of water to a borehole, well or spring.
A confined aquifer is an aquifer that is confined between two layers of soil or rock that are much less pervious than the aquifer.
Principal aquifers are layers of rock or drift deposits that have high intergranular and/or fracture permeability, meaning they usually provide a high level of water storage and transmission. They may support water supply and/or river base flow on a strategic scale. In most cases, principal aquifers are aquifers previously designated as major aquifers.
For more information see: Principal aquifer.
There are two types of secondary aquifer designation:
- Secondary A: permeable layers capable of supporting water supplies at a local rather than strategic scale, and in some cases forming an important source of base flow to rivers. These are generally aquifers formerly classified as minor aquifers.
- Secondary B: predominantly lower permeability layers which may store and yield limited amounts of groundwater due to localised features such as fissures, thin permeable horizons and weathering. These are generally the water-bearing parts of the former non-aquifers.
Ref HS2 London-West Midlands Environmental Statement,November 2013, Volume 1 Glossary of terms and list of abbreviations.
[edit] Related articles on Designing Buildings
- Anisotropic.
- Aquitard.
- Artesian.
- Catchment flood management plans.
- Chalk aquifer.
- Groundwater.
- Groundwater control in urban areas.
- Principal aquifer.
- Secondary aquifer.
- Water engineering.
- Watercourse.
- Water framework directive.
- Water management.
- Water table.
- Why creating new ponds helps to protect the ecosystem.
Featured articles and news
Futurebuild and UK Construction Week London Unite
Creating the UK’s Built Environment Super Event and over 25 other key partnerships.
Welsh and Scottish 2026 elections
Manifestos for the built environment for upcoming same May day elections.
Advancing BIM education with a competency framework
“We don’t need people who can just draw in 3D. We need people who can think in data.”
Guidance notes to prepare for April ERA changes
From the Electrical Contractors' Association Employee Relations team.
Significant changes to be seen from the new ERA in 2026 and 2027, starting on 6 April 2026.
First aid in the modern workplace with St John Ambulance.
Ireland's National Residential Retrofit Plan
Staged initiatives introduced step by step.
Solar panels, pitched roofs and risk of fire spread
60% increase in solar panel fires prompts tests and installation warnings.
Modernising heat networks with Heat interface unit
Why HIUs hold the key to efficiency upgrades.
Reflecting on the work of the CIOB Academy
Looking back on 2025 and where it's going next.
Procurement in construction: Knowledge hub
Brief, overview, key articles and over 1000 more covering procurement.
Sir John Betjeman’s love of Victorian church architecture.
Exchange for Change for UK deposit return scheme
The UK Deposit Management Organisation established to deliver Deposit Return Scheme unveils trading name.
A guide to integrating heat pumps
As the Future Homes Standard approaches Future Homes Hub publishes hints and tips for Architects and Architectural Technologists.
BSR as a standalone body; statements, key roles, context
Statements from key figures in key and changing roles.
Resident engagement as the key to successful retrofits
Retrofit is about people, not just buildings, from early starts to beyond handover.






















Comments
[edit] To make a comment about this article, click 'Add a comment' above. Separate your comments from any existing comments by inserting a horizontal line.