Increasing urban water demand exacerbated by climate change has led to greater pressure among water managers to make e- cient use of available resources. In the past, the solution to meeting demand was to build more dams or access more groundwater from aquifers. In the last 30 years, however, especially in developed countries, the easy sites for further dam construction have

evaporated and those wishing to preserve key environmental assets oen oppose new dams. Increased accession to groundwater has also been of concern in many areas due to the conservation of groundwater-fed environments and concerns about the potential collapse of aquifers.