Mega-scale groundwater quality challenges and the need for an inter-disciplinary approach

A recent Hydrogeology Journal essay flagged a return to groundwater quantity research at the 'mega-scale', as a future focus for hydrogeology (Gleeson and Cardiff 2013). Like the massive groundwater quantity challenges that have been documented in recent 'groundwater depletion' studies (Rodell et al. 2009; Gleeson et al. 2012; Wada et al. 2012; Konikow 2013), groundwater quality issues have also reached a critical stage where they need to be tackled at unprecedented scales (e.g., Ravenscroft et al. 2009; Yaron and Berkowitz 2010; Zheng and Liu 2013). This will require use of the best inter-disciplinary knowledge, tools and co-operation. This essay outlines some of the mega-scale groundwaterquality challenges currently being faced, and highlights how integrated water quality and quantity approaches are needed to address them.