Class 10 Geography Chapter 3 Water Resources Notes

Freshwater Availability and Water Scarcity

Three-fourth of the Earth’s surface covered with water.
Only a small portion is usable freshwater.
Freshwater comes from surface runoff and groundwater, renewed through the hydrological cycle.
Water’s renewability makes it a crucial resource.

Freshwater Availability:

Obtained from surface runoff and groundwater.
Hydrological cycle maintains the availability of freshwater.
Water continuously circulated, ensuring its renewal.

Water Scarcity Despite Abundance:

Paradox: Abundance of water on Earth’s surface, yet water scarcity persists.
Factors contributing to water scarcity:
- Uneven distribution of freshwater resources globally.
- Population growth and increased demand for water.
- Pollution and contamination of available freshwater sources.
- Climate change affecting precipitation patterns.

Predicted Water Scarcity:

Projection: By 2025, approximately two billion people facing absolute water scarcity.
Causes behind the prediction:
- Rapid population growth.
- Increased industrialization and urbanization.
- Depletion of groundwater reserves.
- Insufficient infrastructure for water distribution and storage.

Water Scarcity: Causes, Implications, and Solutions

Despite water’s abundance and renewability, water scarcity is a global concern.
Water scarcity often linked with low rainfall, drought-prone areas, and regions like deserts.
Over-exploitation, excessive use, and unequal access contribute to water scarcity.

Causes of Water Scarcity:

Unequal distribution and variations in seasonal precipitation.
Growing populations demanding more water for domestic use and food production.
Over-exploitation due to agriculture expansion and industrialization.
Urbanization amplifying water and energy demands.
Pollution from domestic, industrial, and agricultural waste.

Agriculture’s Role:

Irrigated agriculture is a major water consumer.
Expanding irrigated areas for increased food production.
Need for innovation in drought-resistant crops and dry farming techniques.

Industrial and Urban Pressures:

Intensive industrialization and urbanization in post-independent India.
Industries as heavy water users; hydroelectric power generation.
Urban centers exerting pressure on water resources.
Groundwater depletion due to urban water pumping devices.

Water Quality Concerns:

Water scarcity not solely about quantity; quality matters too.
Pollution from domestic, industrial, and agricultural sources.
Chemicals, pesticides, and fertilizers contaminating water sources.

Government Initiatives:

Introduction of Jal Jeevan Mission (JJM) in India.
Goal: Assure rural households of potable piped water supply.
Focus on enhancing quality of life, rural development, and ecological sustainability.

Need for Conservation and Management:

Urgent need to conserve and manage water resources.
Prevent health hazards, ensure food security, and protect livelihoods.
Over-exploitation threatens ecosystems and leads to ecological crises.

India’s Rivers in Crisis: Threats to Ecosystem and Survival

Alarming degradation of India’s rivers, including major ones like Ganga and Yamuna.
Rivers turning into toxic streams due to various factors.
Multifaceted assault caused by population growth, agricultural changes, urban expansion, and industrial growth.

Toxic Streams and Impure Rivers:

Even major rivers like Ganga and Yamuna not immune to pollution.
Pollution caused by sewage discharge, industrial effluents, agricultural runoff, and waste dumping.
Degraded water quality poses health risks and ecosystem damage.

Assault on Rivers from Different Sources:

Population growth leading to increased waste and pollution.
Agricultural modernization involving chemical fertilizers and pesticides.
Urbanization contributing to sewage discharge and waste accumulation.
Industrialization releasing pollutants into water bodies.

Impact on Ecosystem and Life:

Severe threat to aquatic life and biodiversity.
Ecosystem imbalance affecting food chains and water-dependent species.
Reduced availability of clean water for various needs.

Growing Threats:

The scale of river degradation increasing rapidly.
Combined effects of population, agriculture, urbanization, and industrialization.
Ecosystem and human livelihoods in jeopardy.

Need for Urgent Action:

Immediate attention required to address river degradation.
Policy interventions, regulations, and awareness campaigns needed.
Transition to sustainable practices in agriculture, industry, and waste management.

Preserving Lifelines:

Rivers as lifelines, vital for agriculture, drinking water, and livelihoods.
Collective responsibility to protect and restore rivers.
Collaborative efforts of government, industries, communities, and individuals crucial.

Multi-Purpose River Projects and Challenges in Integrated Water Resources Management

Historical records reveal ancient water management techniques.
Modern India continues this tradition with multi-purpose river projects.
These projects integrate various uses of water, including irrigation, power generation, and flood control.

Evolution of Dams:

Ancient hydraulic structures like dams, reservoirs, and canals for irrigation.
Modern dams serve multiple functions, including hydropower and water supply.
Dams as symbols of development, integrating agriculture, industry, and urban growth.

Critique of Multi-Purpose Projects:

Recent scrutiny and opposition to large dams and projects.
Altered river flow impacts sediment transport and aquatic habitats.
Fragmented rivers hinder aquatic migration and degrade ecosystems.
Submergence of floodplains affects vegetation, soil, and habitats.

Environmental Movements and Displacement:

Projects like ‘Narmada Bachao Andolan’ and ‘Tehri Dam Andolan’ sparked protests.
Displacement of local communities and loss of livelihoods.
Benefits often skewed towards landowners, industrialists, and urban centers.

Changing Landscape and Ecological Consequences:

Irrigation alters cropping patterns, leading to water-intensive and commercial crops.
Ecological consequences like soil salinization and social disparities.
Conflicts arise from competing demands and unequal distribution of benefits.

Failure to Achieve Objectives:

Some projects fail to fulfill intended purposes.
Dams meant to control floods sometimes exacerbate flooding.
Impact of sedimentation on flood plains and soil degradation.
Induced earthquakes, water-borne diseases, pests, and pollution due to excessive water use.

Water Harvesting as an Alternative: Sustainable Practices and Success Stories

Growing recognition of disadvantages and opposition to multi-purpose projects.
Water harvesting emerges as a viable alternative, aligning with socio-economic and environmental needs.
Ancient Indian water-harvesting practices reveal advanced knowledge of local conditions.

Traditional Water-Harvesting Techniques:

Diverse water-harvesting methods based on rainfall patterns, soil types, and local ecology.
Examples include diversion channels, rooftop rainwater harvesting, and floodplain irrigation channels.

Diverse Applications:

Diversion channels (‘guls’ or ‘kuls’) in hill regions for agricultural purposes.
‘Rooftop rainwater harvesting’ in Rajasthan for drinking water storage.
Inundation channels in Bengal for floodplain irrigation.
‘Khadins’ and ‘Johads’ in arid regions to store rainwater in agricultural fields.

Rajasthan’s Underground Tanks (‘Tankas’):

Underground tankas for drinking water storage in arid and semi-arid regions.
Part of rooftop rainwater harvesting systems.
Rainwater collected from rooftops via pipes and stored in tankas.
Tankas considered reliable water sources during dry spells and summer.

Modern Adaptations and Success Stories:

Gendathur village in Mysuru, Karnataka, a model for rooftop rainwater harvesting.
Annual precipitation of 1,000 mm, with 80% collection efficiency.
Nearly 200 households using rainwater harvesting systems.
Each house collects about 50,000 liters of water annually.
Success stories inspire similar initiatives in rural and urban areas.

Challenges and Decline:

Some traditional practices declining due to access to other water sources.
Perennial canals reducing reliance on rainwater harvesting in Rajasthan.
Focus on tap water leading to decreased preference for harvested rainwater.

Ancient Hydraulic Structures in India: Testament to Advanced Water Management

Ancient India displayed remarkable expertise in hydraulic engineering.
Hydraulic structures played a crucial role in managing water resources.

Evidences of Sophisticated Irrigation:

Sringaverapura, near Allahabad, had floodwater channelling in the 1st century B.C.
Chandragupta Maurya’s time saw construction of dams, lakes, and irrigation systems.
Notable irrigation works found in Kalinga (Odisha), Nagarjunakonda (Andhra Pradesh), Bennur (Karnataka), Kolhapur (Maharashtra), and more.

Prominent Hydraulic Achievements:

Bhopal Lake, 11th century, one of the largest artificial lakes at the time.
14th-century tank in Hauz Khas, Delhi, built by Iltutmish for supplying water to Siri Fort area.

Sophisticated Water Management:

Chandragupta Maurya’s era marked by extensive irrigation and water storage.
Different regions showcased advanced irrigation systems.
Mastery over managing water for agriculture, cities, and fortifications.

Legacy of Knowledge:

Hydraulic achievements reflected deep understanding of local ecology.
Water harvesting, storage, and distribution integrated with local conditions.
Engineering feats symbolized advanced civilization and resourcefulness.

Relevance Today:

Ancient hydraulic structures offer lessons for modern water management.
Sustainability, efficiency, and adaptability remain valuable principles.
Balancing traditional wisdom with contemporary challenges vital.

Dams: Structures, Types, and Classification

Dams are structures built across water bodies to obstruct, redirect, or control the flow of water.
They create reservoirs or impoundments, serving various purposes.

Components and Terminology:

A “dam” refers to the reservoir formed, not just the structure.
Most dams have a spillway or weir for controlled water release.

Types Based on Structure:

Timber Dams: Constructed using wood and logs.
Embankment Dams: Built with compacted earth and rock materials.
Masonry Dams: Constructed using bricks, stones, or concrete blocks.

Types Based on Intended Purpose:

Different dams designed for various purposes, like flood control, water supply, power generation, irrigation, etc.

Classification by Height:

Large Dams: Built for significant water storage or power generation.
Major Dams: Dams of substantial importance based on storage or function.
Low Dams: Smaller in height, used for minor water control or diversion.
Medium Height Dams: Intermediate in size, serving multiple purposes.
High Dams: Taller structures designed for larger water storage or power generation.

Dams and Their Functions:

Flood Control: Dams manage and regulate water flow during heavy rains to prevent flooding.
Water Supply: Dams store water for domestic, industrial, and agricultural needs.
Hydropower Generation: Water flow through turbines produces electricity.
Irrigation: Dams release water for controlled irrigation in agriculture.
Recreation: Dams create reservoirs used for recreational activities like boating and fishing.

Impact and Considerations:

Dams offer benefits but can also have environmental and social consequences.
Ecological impact on river systems, sediment flow, aquatic habitats, and fish migration.
Displacement of communities due to reservoir creation.
Balancing the benefits and drawbacks of dam construction is essential.

Narmada Bachao Andolan: A Struggle for Rights and Rehabilitation

Narmada Bachao Andolan (NBA) is a prominent Non-Governmental Organization (NGO).
Mobilized diverse groups against the construction of the Sardar Sarovar Dam on the Narmada river in Gujarat.

Origins and Focus:

NBA initially centered on environmental concerns, particularly submerged trees.
Evolved to advocate for comprehensive rehabilitation of displaced people.

Campaign Against Sardar Sarovar Dam:

Mobilized tribal communities, farmers, environmentalists, and human rights activists.
Fought against the construction of the Sardar Sarovar Dam due to environmental and social impacts.
Brought attention to the displacement of communities due to the dam’s construction.

Aims and Transformation:

NBA re-focused on ensuring proper rehabilitation for displaced citizens, especially oustees.
Highlighted the need for the government to provide complete rehabilitation facilities.
Struggle for social justice, human rights, and protection of livelihoods.

Narratives of Sacrifice and Questioning:

People initially endured displacement believing in promises of progress and benefits.
Acceptance of hardships as a national sacrifice for better prospects.
After years of displacement, questions arose about the unequal distribution of sacrifices.

Ongoing Struggle:

Struggle continues for just rehabilitation, livelihoods, and rights.
Advocates for equitable distribution of benefits and compensation.
Represents a larger narrative of social and environmental justice.

Sardar Sarovar Dam: A Major Multi-State Water Resource Project

The Sardar Sarovar Dam stands over the Narmada River in Gujarat, India.
It ranks among India’s largest water resource projects, spanning four states.

Project Coverage:

Encompasses the states of Maharashtra, Madhya Pradesh, Gujarat, and Rajasthan.
Aims to provide water resources across these states.

Water Supply Objectives:

Addressing water scarcity in drought-prone and desert areas.
Catering to the needs of 9,490 villages and 173 towns in Gujarat.
Providing water to 124 villages in Rajasthan.

Sardar Sarovar Project’s Significance:

Seeks to alleviate water shortages in arid and desert regions.
Key infrastructure for water supply, irrigation, and power generation.
An ambitious endeavor aimed at promoting agricultural growth and economic development.

Multi-Purpose Benefits:

Water Supply: Provides water to regions facing chronic water scarcity.
Irrigation: Facilitates irrigation to enhance agricultural productivity.
Power Generation: Harnesses hydropower potential for electricity generation.

Controversies and Disputes:

Environmental and social concerns have surrounded the project.
Displacement of communities, ecological impact, and questions of equitable distribution.

Balancing Development and Conservation:

Striking a balance between development goals and environmental conservation.
Challenges include ensuring the well-being of displaced populations and maintaining ecological equilibrium.

Krishna-Godavari River Dispute: Water Allocation and Interstate Conflicts

The Krishna-Godavari river dispute involves Karnataka, Andhra Pradesh, and Maharashtra.
Centered on water diversion at Koyna by Maharashtra for a multipurpose project.

Dispute Overview:

Maharashtra’s project involves diverting more water at Koyna.
Karnataka and Andhra Pradesh governments raise objections due to downstream implications.

Water Diversion and Consequences:

Maharashtra’s project would lead to reduced downstream flow in Karnataka and Andhra Pradesh.
Adverse impacts on agriculture and industries in these states.
The dispute underscores the interconnectedness of water resources across states.

Interstate Conflicts and Concerns:

Concerns about equitable distribution of water resources.
Tensions arise when one state’s development affects another’s water availability.
Disputes highlight the complexities of balancing developmental needs with the shared nature of water resources.

Multipurpose Projects and Impacts:

Multipurpose projects often serve various needs but can lead to conflicts.
Need for careful planning and collaboration among states to mitigate negative impacts.

Resolution Efforts:

Resolving interstate water disputes requires negotiation and cooperation.
Legal frameworks like water-sharing agreements may be necessary.
Collaborative management and long-term sustainability are key considerations.

Rooftop Rainwater Harvesting in Shillong: Addressing Water Scarcity in a Rain-Rich Region

Rooftop rainwater harvesting is a prevalent practice in Shillong, Meghalaya.
Despite being in proximity to some of the world’s highest rainfall areas, Shillong faces water scarcity.

Rainfall Discrepancy and Water Scarcity:

Cherapunjee and Mawsynram, just 55 km from Shillong, receive world’s highest rainfall.
Despite abundant rainfall nearby, Shillong experiences acute water shortage.

Widespread Implementation:

Rooftop rainwater harvesting structures are common in Shillong.
Practiced in nearly every household to alleviate water scarcity.

Effective Water Source:

Rainwater harvesting contributes significantly to water availability in households.
About 15-25% of the total water requirement is met through rooftop water harvesting.

Importance of Rooftop Rainwater Harvesting:

Mitigates water scarcity by harnessing abundant rainfall.
Enhances local water self-sufficiency and resilience.

Factors Contributing to Water Scarcity:

Factors like rapid urbanization, population growth, and infrastructure development.
Insufficient infrastructure to capture and store rainwater.

Benefits and Challenges:

Benefits include reduced reliance on external water sources and improved water security.
Challenges include maintaining and managing the rainwater harvesting systems.

Local Solutions for Global Issues:

Shillong’s example emphasizes the need for context-specific solutions to water scarcity.
Illustrates that abundant rainfall does not guarantee access to reliable water sources.

Tamil Nadu’s Trailblazing Initiative: Mandatory Rooftop Rainwater Harvesting

Tamil Nadu leads as the pioneer state in India to mandate rooftop rainwater harvesting.
The state has made it compulsory for all houses, backed by legal provisions and penalties.

Mandatory Rooftop Rainwater Harvesting:

Tamil Nadu’s proactive step aims to address water scarcity and promote sustainable water management.
Every house in the state is required to have a rooftop rainwater harvesting structure.

Significance of the Initiative:

Represents a forward-thinking approach to tackle water scarcity and ensure water self-sufficiency.
Addresses the state’s water challenges by harnessing rainwater.

Legal Backing and Penalties:

Legal provisions ensure compliance with the mandatory rainwater harvesting requirement.
Defaulters may face penalties or consequences for non-compliance.

Benefits of Mandatory Rainwater Harvesting:

Enhances water availability and security.
Promotes water conservation, reduces reliance on external water sources.

Inspiration for Other Regions:

Tamil Nadu’s initiative sets an example for other states facing water scarcity.
Encourages governments to explore similar policies to alleviate water stress.

Challenges and Implementation:

Ensuring proper implementation and maintenance of rainwater harvesting structures.
Overcoming challenges related to awareness, technology, and community involvement.

Sustainable Water Management:

Tamil Nadu’s approach highlights the importance of proactive policies for sustainable water management.
Demonstrates the potential for impactful change through legislative measures.