Public groundwater supplies: minimising operational costs and carbon footprints

The key factors determining the operational cost and carbon footprint of public water supplies derived from groundwater are identified. Both remain low compared to alternative sources while groundwater levels remain stable and water quality potable, but can increase markedly if derived from overexploited and/or polluted aquifers. Thus, ‘potable source protection zones’ are strongly advocated, and examples from England (UK) and Spain are illustrated. The concept of minimising the carbon footprint of groundwater use for potable water supply is novel, and deserves greater attention.