BGS carried out investigations on the baseline quality of groundwater in aquifers of England and Wales between the late 1990s and 2015. A series of 23 reports and an overall synthesis report were produced as part of this investigation in a collaboration between BGS and the Environment Agency between 2002 and 2005. These are available for download.

Groundwater sampling from boreholes beneath standing water on the River Thames floodplain near Oxford. BGS © UKRI.
Reports
- The Bridport Sands of Dorset and Somerset
- The Carboniferous Limestone of northern England
- The Chalk and Crag of north Norfolk and the Waveney catchment
- The Chalk aquifer of Yorkshire and north Humberside
- The Chalk of Dorset
- The Chalk of the Colne and Lee river catchments
- The Chalk of the North Downs, Kent and east Surrey
- The Corallian of Oxfordshire and Wiltshire
- The Devonian aquifer of South Wales and Herefordshire
- The granites of south-west England
- The Great and Inferior Oolite of the Cotswolds district
- The Great Ouse Chalk aquifer, East Anglia
- The Lincolnshire Limestone
- The Lower Greensand of southern England
- The Millstone Grit of northern England
- The Ordovician and Silurian meta-sedimentary aquifers of central and south-west Wales
- The Palaeogene of the Wessex Basin
- The Permo-Triassic sandstone aquifer of Shropshire
- The Permo-Triassic sandstones of Liverpool and Rufford
- The Permo-Triassic sandstones of Manchester and east Cheshire
- The Permo-Triassic sandstones of south Staffordshire and north Worcestershire
- The Permo-Triassic sandstones of west Cheshire and the Wirral
- The Triassic sandstones of the Vale of York