Understanding Why a Small Proportion of It Accounts for Freshwater Use in Class 10 Social Science

Why a Small Proportion of It Accounts for Usable Freshwater

Although water covers about three-fourths of the Earth's surface, only about 2.5% of it is freshwater. Of this freshwater, a large amount is locked in glaciers, ice caps, and deep underground aquifers, making only a small proportion accessible for human use. The main sources of usable freshwater are surface runoff from rivers and lakes, and groundwater that can be extracted through wells.

This limited availability is why a small proportion of it accounts for the water we use daily. Freshwater is continually renewed through the hydrological cycle, but uneven distribution and accessibility challenges mean many regions face shortages despite the abundance of water globally.

Causes of Water Scarcity in India and Its Impact

Water scarcity occurs when the demand for water exceeds the available supply. In India, both natural and human factors contribute to this scarcity:

• Natural causes: Low rainfall, drought-prone areas, and seasonal variations reduce water availability.
• Human causes: Over-extraction of groundwater, population growth, urbanization, and pollution increase demand and reduce quality.

For example, cities with large populations often face water shortages because the demand for domestic, agricultural, and industrial use exceeds supply. Overuse of groundwater for irrigation lowers water tables, threatening food security. Water scarcity affects health, agriculture, and livelihoods, making it a critical issue for sustainable development.

How Water Becomes a Renewable Resource

Water is considered a renewable resource because it is continuously recycled through the hydrological cycle:

• Evaporation: Water from oceans, lakes, and rivers evaporates into the atmosphere.
• Condensation: Water vapor forms clouds.
• Precipitation: Rain or snow returns water to the surface.
• Runoff and infiltration: Water flows into rivers or seeps into the ground to recharge aquifers.

This cycle renews freshwater supplies, but the rate of renewal and accessibility vary by region. Sustainable management is essential to ensure that water use does not exceed natural replenishment.

The Role of Agriculture and Industry in Water Demand

Agriculture is the largest consumer of freshwater in India, accounting for about 80% of total water use. Irrigated farming requires large volumes of water, often leading to groundwater depletion. Over-extraction can cause falling water tables and reduce water availability for future use.

Industries also demand significant water, especially for cooling, processing, and cleaning. Urbanization increases domestic water consumption. Both sectors contribute to water pollution through discharge of untreated waste, further reducing usable water.

Efficient water use and pollution control in these sectors are vital for water sustainability.

Water Pollution and Its Effect on Water Scarcity

Even when water quantity is sufficient, pollution can make water unsafe for use, effectively causing scarcity. Common pollutants include:

• Domestic sewage
• Industrial effluents
• Agricultural chemicals like pesticides and fertilizers

Polluted water harms human health and ecosystems. It increases treatment costs and limits water availability for drinking, farming, and industry. Protecting water quality is as important as conserving quantity to address water scarcity effectively.

Government Initiatives and Water Conservation Methods

The Government of India has launched several initiatives to tackle water scarcity, including the Jal Jeevan Mission (JJM), which aims to provide potable piped water to every rural household at 55 litres per capita per day.

Water conservation methods include:

• Rainwater harvesting: Collecting and storing rainwater for later use.
• Multi-purpose river projects: Dams and canals to regulate water flow, control floods, and generate hydroelectricity.
• Efficient irrigation techniques: Drip and sprinkler irrigation reduce water wastage.
• Public awareness campaigns: Educating people on water-saving practices.

These efforts help manage water sustainably, ensuring availability for future generations.