Introduction

Water is often taken for granted — we assume that what exists today will continue to exist tomorrow. But the future is likely to be very different. Societies will experience demographic transition, a geographical shift of population, technological advancement, environmental degradation, and, most critically, water scarcity. Among all these challenges, water scarcity is expected to be the greatest, because demand is rising sharply while supplies are shrinking due to overuse and pollution.

Water is a cyclic resource — it moves through the hydrological cycle and is, in principle, abundant. About 71 per cent of the Earth's surface is covered with water. However, freshwater — the kind usable by humans — makes up only about 3 per cent of the total water on the planet. And of that tiny fraction, only a very small proportion is actually available for human use. The rest is locked in glaciers, ice caps, or deep underground.

The availability of freshwater is not uniform. It varies over space (some regions get plenty, others very little) and over time (some seasons are wet, others dry). This unevenness leads to tensions and disputes over sharing and control of water — conflicts that are increasingly common among communities, regions, and even states.

Because water is both scarce and unevenly distributed, its assessment, efficient use, and conservation become essential for development. This chapter examines India's water resources: their geographical distribution, how different sectors use water, and the methods adopted for conservation and management.