This title offers 100 papers from 20 countries, covering the most up-to-date research and state of the art on a widening range of methods for recharge enhancement and groundwater quality protection and improvement. These include bank filtration, aquifer storage and recovery and soil aquifer treatment as well as rainwater harvesting and pond infiltration. The emphasis is on understanding subsurface process to improve siting, design and operation and facilitate use of stormwater and reclaimed water, particularly in water-scarce areas.