Water Resources

The hydrological cycle describes the continuous movement of water on, above, and below the surface of the Earth. It includes processes like evaporation, condensation, precipitation, and runoff. This cycle replenishes freshwater sources, making water a renewable resource. For example, rainwater fills rivers and lakes, which are then used for various purposes.

Water scarcity occurs because only a small proportion of Earth's water is freshwater suitable for use. Factors like over-exploitation, unequal access, and pollution reduce available freshwater. For instance, in Rajasthan, despite the Indira Gandhi Canal, water scarcity persists due to overuse and pollution.

Urban areas face water scarcity due to high population density, overuse of groundwater, and pollution. Industries and urban lifestyles increase demand, while pollution makes existing water unsafe. Cities like Chennai experience scarcity despite adequate rainfall due to mismanagement and pollution.

Multi-purpose river projects integrate irrigation, electricity generation, and flood control. They store water in reservoirs for dry seasons, like the Bhakra-Nangal project. However, they can also lead to ecological issues like sedimentation and habitat fragmentation.

These projects can cause displacement of communities, ecological imbalance, and sedimentation. For example, the Sardar Sarovar Dam led to habitat loss and disputes over water sharing. They may also fail in flood control during excessive rainfall.

In Rajasthan, rooftop rainwater is channeled into underground 'tankas' through pipes. The first rain cleans the roof, and subsequent showers are stored. This method provides drinking water during dry months, as seen in Phalodi's traditional homes.

The Jal Jeevan Mission aims to provide piped potable water to every rural household. It ensures 55 litres per capita daily, improving quality of life. This initiative addresses water scarcity and promotes sustainable management, as highlighted in the Economic Survey 2020-21.

Industries discharge chemicals, heavy metals, and waste into water bodies, making water unsafe. For example, textile industries release dyes and toxins. This pollution affects aquatic life and human health, necessitating strict regulations and treatment plants.

Traditional methods include 'kuls' in Himalayas, 'tankas' in Rajasthan, and 'inundation channels' in Bengal. These systems are adapted to local conditions, like 'jhons' in Rajasthan for agriculture. They showcase indigenous knowledge of water conservation.

The dispute arises from Maharashtra diverting water at Koyna, reducing flow to Karnataka and Andhra Pradesh. It highlights inter-state conflicts over water sharing, affecting agriculture and industry. Such disputes underscore the need for equitable water distribution policies.

Dams regulate river flow, storing excess water during rains and releasing it gradually. However, sedimentation can reduce their effectiveness, as seen in the Hirakud Dam. Proper management is crucial to prevent floods and ensure water availability.

This scheme focuses on sustainable groundwater management in water-stressed areas. It encourages community participation and efficient water use, like in Gujarat's 80 districts. The goal is to ensure long-term water security through behavioral changes.

Overuse lowers water tables, causing wells to dry up and land subsidence. In Punjab, excessive irrigation has depleted aquifers and increased salinity. Sustainable practices, like drip irrigation, are needed to mitigate these effects.

Modern adaptations, like rooftop harvesting in Karnataka's Gendathur village, combine traditional knowledge with technology. They enhance water availability and reduce dependence on external sources. Such systems are scalable and environmentally friendly.

This scheme aims to expand irrigated areas and improve water use efficiency. It promotes 'per drop more crop' through micro-irrigation. By reducing wastage, it ensures better productivity and water conservation in agriculture.

Sedimentation reduces reservoir capacity and disrupts aquatic ecosystems. For example, the Tehri Dam faces silt accumulation, impacting its longevity. Regular desilting and watershed management are essential to maintain dam functionality.

This 200-year-old system uses bamboo pipes to transport water efficiently. It minimizes wastage and ensures precise watering, ideal for hilly terrains. Such indigenous practices are cost-effective and sustainable.

Agriculture consumes 70% of freshwater, making conservation vital for crop production. Overuse depletes resources, threatening food supply. Techniques like drought-resistant crops and efficient irrigation can secure water for future needs.

Polluted water causes diseases like cholera and dysentery. Industrial toxins can lead to long-term illnesses, such as cancer. Access to clean water is essential to prevent health crises, especially in rural areas.

Urbanisation increases demand for water while reducing recharge areas. Concrete surfaces prevent rainwater infiltration, lowering groundwater levels. Cities like Bengaluru face scarcity due to rapid urban growth and poor planning.

Individuals can fix leaks, use water-efficient appliances, and practice rainwater harvesting. Simple actions, like shorter showers and reusing water, can significantly reduce consumption. Community awareness is key to sustainable water use.

Climate change alters rainfall patterns, causing droughts and floods. Melting glaciers reduce freshwater availability, affecting rivers like the Ganges. Adaptive strategies, like better storage and conservation, are needed to cope with these changes.

Governments implement policies like the Jal Jeevan Mission and regulate industrial discharge. They promote infrastructure projects and community participation. Effective governance ensures equitable distribution and sustainable use of water resources.

Disputes can be resolved through tribunals, equitable sharing agreements, and collaborative management. The Krishna-Godavari dispute highlights the need for legal frameworks and dialogue to ensure fair distribution among states.

This method provides a reliable water source, reduces runoff, and lowers demand on groundwater. In Tamil Nadu, it's mandatory, ensuring water availability during shortages. It's a simple, cost-effective solution for urban and rural areas.