Artificial recharge (AR) is defined as a man-made operation aimed at transferring water from the ground surface into an underlying aquifer. While groundwater recharge, i.e. natural replenishment, can be regarded as (mostly) uncontrolled (by man) input into the groundwater system, AR is defined as a controlled input. Artificial recharge, where implemented, is an intrinsic element of a groundwater, or water resources system and thus the quantity, quality, location, and scheduling of AR are decision variables of planning and management of the system. Recent research on climate change predicts a reduction in rainfall and in natural replenishment in many groundwater basins around the world. This makes AR an important tool for augmenting available groundwater in such areas.
Artificial recharge may be practiced in order to achieve various objectives, e.g., (a) control of the regional flow regime (sea water intrusion, contaminant transport), (b) long term and short term storage of water, primarily in phreatic aquifers (conjunctive use, reduction of evaporation), and (c) improvement of water quality as a consequence of mixing or the interaction between chemical compounds or pathogens transported in the fluid and the aquifer solids (and sometimes the unsaturated zone). Induced recharge, i.e. bank filtration from rivers may also be considered as artificial recharge, achieving primarily the goal of quality improvement.
Planning artificial recharge within the framework of a water resources (or ground water) planning requires (a) identification of the respective necessity, (b) understanding of flow and reactive transport processes in saturated and unsaturated media, (c) site selection and characterization, (d) system design by (flow and reactive transport) modeling of alternatives, based on process understanding, (e) economic considerations, (f) socio-economic aspects, and (g) solution of management issues.
Contributions are invited within the context of the topic described. Examples could be:
• The role of AR within a water resources system
• Relevant flow and reactive transport processes in AR
• Modeling flow and reactive transport associated with AR.
• Design and planning of an AR project
• AR with different sources of water (e.g. treated effluent, flood water, river water)
• Monitoring tools and techniques after the spreading water
• Management of AR systems as part of IWRM concepts.
• Economic and socio-economic aspects
• Examples and case studies.