Maarg Manthan · Topic 11.1

Surface Water Resources and Groundwater Resources

Environment & Ecology › Water Resources and Water Pollution · Topic 11.1

India supports about 17 to 18 percent of the world's population with roughly 4 percent of its freshwater, so water is a limiting resource. Water resources are of two kinds: surface water in rivers, lakes, ponds, reservoirs and glaciers, and groundwater held in aquifers beneath the ground. India receives about 4,000 billion cubic metres (BCM) of precipitation a year, mostly in the June to September monsoon, but only part is usable: the Central Water Commission puts the average annual water resource of the country's rivers at about 1,999 BCM and the utilisable resource at about 1,122 BCM, of which around 690 BCM is surface water and 432 BCM replenishable groundwater; check the latest assessments. Per capita availability has fallen to about 1,400 to 1,500 cubic metres a year, below the water-stress threshold of 1,700. India is the world's largest user of groundwater, which supplies most irrigation and rural drinking water, and overuse has put many blocks in the over-exploited category.

5 min read · UPSC Prelims · Environment & Ecology · Water Resources and Water Pollution

At a Glance

Share of world water About 4 percent
Share of population About 17 to 18 percent
Utilisable water About 1,122 BCM
Stress threshold 1,700 cubic m per person
Top groundwater user India
Exam link UPSC Prelims, Environment & Ecology: Water Resources and Water Pollution

Where Does It Fit?

This is the first topic of the macro on water resources and water pollution. It sets the supply picture before the topics on sources of water pollution, measurement, effects, eutrophication and contaminants. Previous topic: Organic Farming. Next topic: Sources and Causes of Water Pollution.

How Is India’s Water Resource Divided?

Component	Features
Annual precipitation	About 4,000 BCM including snowfall, mostly in the monsoon
Average annual river flow	About 1,999 BCM as per Central Water Commission estimates
Utilisable surface water	About 690 BCM, limited by topography and storage
Replenishable groundwater	About 432 BCM utilisable; net annual extractable groundwater is assessed by CGWB state by state
Total utilisable	About 1,122 BCM
Per capita availability	Falling with population growth; below 1,700 cubic metres means stress and below 1,000 means scarcity
Use pattern	Agriculture takes around four-fifths of water withdrawn

What Do Surface Water and Groundwater Offer and Face?

Surface water: rivers like the Ganga, Brahmaputra, Indus and Godavari, plus reservoirs, tanks and lakes
Surface water problems: seasonal flow, floods and droughts, interstate disputes and pollution
Groundwater: stored in alluvial aquifers of the Indo-Gangetic plain and in hard rock aquifers of the peninsula
Groundwater share: supplies over half of irrigated area and most rural drinking water
Over-exploitation: falling water tables in Punjab, Haryana, Rajasthan, Delhi and parts of the south
Quality issues: fluoride, arsenic, salinity, nitrate and iron in some areas
Agencies: Central Water Commission for surface water and Central Ground Water Board for groundwater
Schemes: Atal Bhujal Yojana, Jal Shakti Abhiyan, Jal Jeevan Mission and Pradhan Mantri Krishi Sinchayee Yojana

What Else Should You Remember?

Water cycle role: monsoon rain feeds rivers and recharges aquifers; glaciers feed Himalayan rivers
Major basins: Ganga-Brahmaputra-Meghna is the largest, followed by the Indus and Godavari
Himalayan rivers: perennial, fed by rain and snow
Peninsular rivers: seasonal, depend on monsoon
Reservoir storage: India stores only a modest share of annual flow compared with some countries
Groundwater extraction: India extracts the largest amount in the world, a large share of global groundwater use
Stage of extraction: ratio of annual extraction to annual extractable resource; assessment units are classed safe, semi-critical, critical or over-exploited
Dynamic resource assessment: CGWB and states assess groundwater resources periodically
Aquifer types: alluvial aquifers are rich and productive, hard rock aquifers hold less and recover slowly
Water table: the upper surface of the saturated zone
Recharge: rainfall, canal seepage, return flow from irrigation and ponds
Free power: subsidised farm electricity encourages pumping
Crop pattern: water-heavy rice and sugarcane in dry regions
Rainwater harvesting: roof and field structures to recharge groundwater
Atal Bhujal Yojana: a scheme launched in 2019 for community-led groundwater management in water-stressed areas of seven states
Jal Shakti Abhiyan: a campaign for water conservation in water-stressed districts
National Water Policy: 2012 policy treats water as a scarce resource to be managed with a river basin approach
National Water Mission: one of the eight missions under NAPCC, aiming at 20 percent higher water use efficiency
Interstate disputes: Cauvery, Krishna and Godavari are examples
Transboundary rivers: the Indus Waters Treaty with Pakistan and Ganga and Teesta issues with Bangladesh
Link to previous: see Organic Farming
Link to next: see Sources and Causes of Water Pollution
Link to wetlands: see Wetlands in India and Threats to Wetland Ecosystems
Caution: water resource figures are revised in each assessment, so use the latest CWC and CGWB numbers
Exam hint: remember the stress and scarcity thresholds and the main agencies and schemes
Glacier and snow melt: Himalayan glaciers feed the Indus, Ganga and Brahmaputra and keep them flowing in the dry season, but melt patterns are shifting with warming
Rural drinking water: most rural households depend on handpumps and wells drawing groundwater

Why Does It Matter for the Exam?

Stress limit: 1,700 cubic m
Scarcity limit: 1,000 cubic m
Agencies: CWC, CGWB
Current affairs link: Atal Bhujal and Jal Jeevan
Common errors: confusing precipitation with utilisable water

As an analytical point, India’s water problem is less about total rain than about timing, storage, quality and use. Fixing crop choices, power pricing and recharge matters as much as building new storage.

Why Is This Topic Important?

Supply Monsoon bound
Groundwater Overused
Fix Recharge, efficiency

What Came Next?

The next topic covers the sources and causes of water pollution. Next topic: Sources and Causes of Water Pollution.

Key People and Terms

BCM Billion cubic metres
Aquifer Water-bearing rock layer
Water table Top of saturated zone
Recharge Refill of groundwater
CWC Central Water Commission
CGWB Central Ground Water Board

Exam Corner

Points to Remember

India has about 4 percent of world freshwater.
Utilisable water about 1,122 BCM.
Stress below 1,700 cubic m.
Largest groundwater user.
Atal Bhujal began in 2019.

Do Not Confuse With

Precipitation and utilisable water Total rain versus usable share
CWC and CGWB Surface water versus groundwater body
Water stress and scarcity 1,700 versus 1,000

Memory Hook

Four percent water, eighteen percent people, monsoon fills, pumps drain.

Mains Angle

Questions ask for numbers and agencies. These points help.

Supply Uneven
Use Farm heavy
Fix Recharge

A Question You May Face

An original practice question, not a past paper question.

“Discuss the status of surface water and groundwater resources in India and the challenges in their management.”

How to Answer

Supply Numbers.
Use Farm.
Problems Depletion.
Way Recharge.

GS Relevance

Prelims: water numbers, agencies, schemes. GS Paper 1 and 3: water resources and management.

Frequently Asked Questions

How much water resource does India have?

India receives about 4,000 billion cubic metres of precipitation a year. The average annual flow of its rivers is estimated at about 1,999 billion cubic metres, and the utilisable water resource at about 1,122 billion cubic metres, of which around 690 is surface water and 432 is replenishable groundwater. These figures are updated by the Central Water Commission.

What is the water stress threshold?

A country is considered water-stressed when per capita water availability falls below 1,700 cubic metres per year, and water-scarce when it falls below 1,000. India's per capita availability has dropped to roughly 1,400 to 1,500 cubic metres, which places it in the water-stress category and shows a falling trend.

Why is groundwater important in India?

Groundwater supplies a large part of irrigation and most of rural and a large share of urban drinking water in India. India is the world's biggest user of groundwater, and over-pumping, helped by free or cheap farm power, has lowered water tables in states such as Punjab, Haryana, Rajasthan and Delhi.

Which agencies manage India's water data?

The Central Water Commission handles surface water data, planning and basin studies, while the Central Ground Water Board assesses and monitors groundwater resources. Both work under the Ministry of Jal Shakti. States have their own groundwater departments, and groundwater is assessed block by block as safe, semi-critical, critical or over-exploited.

What is the Atal Bhujal Yojana?

The Atal Bhujal Yojana, launched in 2019, is a central scheme for community-led sustainable groundwater management in water-stressed areas of seven states: Gujarat, Haryana, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan and Uttar Pradesh. It focuses on demand-side management, participatory planning and better data.

PYQ Practice — Statement Analysis

1 India has about 4 percent of the world's freshwater.

True

For a large population.

2 Water stress means below 1,000 cubic metres per person.

False

Stress is below 1,700.

3 India is the largest user of groundwater in the world.