Coastal groundwater management requires special attention due to the problem of saline water intrusion. Since the offshore saltwater and onshore fresh groundwater are of different unit weights, any hydraulic imbalance is likely to initiate a density stratified flow between them. The invasion of saltwater from the sea into the inland freshwater aquifer is termed as ‘saline water intrusion’, whereas the opposite phenomenon is called ‘submarine groundwater discharge’. Excessive pumping operations is coastal regions to withdraw fresh groundwater for domestic, irrigational and industrial usages initiates advancement of the saltwater interface inward, introducing saline water intrusion and associated hazards. The saltwater intrusion is also produced under the action of heavy storm or Tsunami, which initiates invasion of seawater under pressure into freshwater zone. The exposure of aquifer material to saltwater also produces significant alteration in its hydraulic conductivity and other geotechnical and geohydraulic properties, which in turn alters the groundwater flow pattern. A new technique has been introduced by the authors which ensure effective coastal groundwater management. The method includes withdrawal of fresh groundwater by qanat-well structure and recharging the freshwater aquifer by artificial rainwater harvesting. The technique is suitable for localized communities with low to medium population densities. The efficiency of the methodology has been studies in details and relevant conclusions are drawn therefrom. 
Key Words: Aquifer, Groundwater flow, Qanat, Rainwater harvesting, Saltwater.

Professor Sudip Basack, PhD, FIE, FIGS, CEng, M.ASCE, is a geotechnical and geoenvironmental expert with research expertise in diversified areas related to civil engineering. Being a PhD (Engineering) from Jadavpur University, Kolkata, India and a Post-doctorate from the world-renowned Centre of Geomechanics and Railway Engineering, University of Wollongong, New South Wales, Australia, he has more than 20 years’ of professional experience in responsible senior positions in India and overseas. His professional contribution has been characterized by research excellence in close collaboration with academia and industry and the implementation of innovative research-based solutions. He published more than 125 publications in reputed journals and conferences including top-class journals of ASCE, Springer, Elsevier, Taylor and Francis, etc., and several books He is the recipient of numerous academic and research awards and recognitions at national and international levels. He has supervised more than 12 research scholars (Masters and PhD) and implemented several externally funded R & D projects. He has undertaken frequent short-term and long-term academic visits in many countries including USA, UK, Germany, Australia, New Zealand, Singapore, Malaysia, China, etc. Over last few decades, his research covers a wide spectrum of applications from theory to practice, particularly in the following areas: pile foundation, ground improvement, transport geotechnics, groundwater hydraulics, construction management, solid mechanics, etc.