Water Scarcity is one of the most important environmental hazards world-over associated with atmosphere, hydrosphere, lithosphere, and biosphere. In spite of receiving intensive orographic rainfall, different sources of fresh water; most parts of the population is facing increasing water scarcity day by day. It is more prevalent in the under developed as well as developing countries, than in comparison to the developed ones. The water scarcity is having multiple reasons behind it. in the broader sense, the causes behind the water crisis are mainly of two types. They are either natural or anthropological. The present paper tries to focus on the mechanisms of water scarcity from the perspectives of physical processes and anthropogenic processes. Today's water scarcity in the developing and under developed world is mostly triggered by anthropogenic activities decreasing water supply both in relative term and absolute term. This paper finally presents some measures that can be taken to reduce the hazardous effects of water scarcity for sustainable development of the ecologically fragile ecosystems. At the end, this paper also tries to throw some light as a solution to this problem (in a long term way) for betterment of inhabitants of those water scarce regions of the world.