Waterscarcity can be defined as a condition in which people lack sufficient water or else do not have access to safe water supplies. a lack of access to fresh, potable water for drinking and sanitation. in the developing world, finding a reliable source of safe water is often time consuming and expensive. This is known as economic scarcity. In other areas, the lack of water is a more profound problem. There simply isn't enough. That is known asphysical scarcity. The problem of water scarity is a growing one. As more people put ever increasing demands on limited supplies, the cost and effort to build or even maintain access to water will increase. And water's importance to political and social stability will only grow with the crisis.
Water scarcity already affects every continent. Around 1.2 billion people, or almost one-fifth of the world's population, live in areas of physical scarcity, and 500 million people are approaching this situation. Another 1.6 billion people, or almost one quarter of the world's population, face economic water shortage
At the current consumption rate, this situation will only get worse. By 2025, two-thirds of the world’s population may face water shortages. And ecosystems around the world will suffer even more.
POLLUTION
Water pollution comes from many sources including pesticides and fertilizers that wash away from farms, untreated human wastewater, and industrial waste. Even groundwater is not safe from pollution, as many pollutants can leach into underground aquifers.