Water demand: sectoral use, irrigation need and efficient irrigation

Detail

1. Sectoral water use: who uses India's water?

• Sectoral water use means how a country's water is shared among agriculture, industry and domestic (household) users.
• India is an agrarian economy. This means farming is the main job of most people. So the Five Year Plans put irrigation first in water development.
• Share of each sector (NCERT, Class 12):

Sector	Surface water (rivers, lakes, tanks)	Groundwater (wells, tubewells)
Agriculture	89%	92%
Industry	2%	5%
Domestic	9%	3%

• How to read the table:
• Agriculture uses most of both kinds of water.
• Industry takes more of its water from groundwater (5%) than from surface water (2%).

• Households take more of their water from surface water (9%) than from groundwater (3%).

• Trend: as the economy grows, factories and cities grow too. So the industrial and domestic shares will rise, and the farm share will shrink in relative terms.

• Future demand: the National Commission on Integrated Water Resources Development (NCIWRD, 1999) said demand could rise to about 1,180 cubic km by 2050 in its high-demand scenario. This is close to India's utilisable water resource (the water that can actually be captured and used, about 1,122 cubic km). So India could reach its water limit by the middle of the century.
• Groundwater today (Dynamic Ground Water Resource Assessment 2024):
• Total yearly groundwater recharge (water that soaks back into the ground): 446.90 billion cubic metres (BCM) [3]
• Water that can be safely taken out each year (extractable resource): 406.19 BCM [3]
• Water actually taken out each year: 245.64 BCM [3]
• Stage of groundwater extraction (water taken out ÷ water that can be taken out) is 60.47% for India as a whole [3]. Each assessment unit is labelled Safe, Semi-critical, Critical or Over-exploited by this ratio.
• Example of how much farms take: in Andhra Pradesh (2024), irrigation takes 86% of groundwater drawn, domestic use 13% and industry 1% [4].

2. Why India needs irrigation

• Irrigation means giving water to crops by artificial means (canals, wells, tanks) when rain is too little or comes at the wrong time.
• Reason 1: rainfall is uneven in space and time.
• Spatial variability: some places get heavy rain and others very little.

• Temporal variability: most rain falls in about four monsoon months (June–September).

• Reason 2: drought-prone areas.

• The north-west (Rajasthan, parts of Gujarat and Haryana) and the Deccan Plateau get little rain that cannot be trusted.

• Reason 3: dry seasons. Most of India has dry winters and dry summers, so rabi and zaid crops (the winter and short summer crops) need irrigation.

• Reason 4: monsoon breaks and failures.
• Even wet states like West Bengal and Bihar face breaks in the monsoon (dry gaps of days or weeks during the rainy season) or monsoon failure.

• This causes dry spells that harm standing crops.

• Reason 5: thirsty crops. Rice, sugarcane and jute need a lot of water. Where rain is not enough, they need irrigation.

3. What irrigation does for farming

• Multiple cropping: with assured water, a farmer can grow two or three crops a year on the same land.
• Higher productivity: irrigated land gives much higher yields than land that depends only on rain.
• HYVs (high-yielding varieties): improved seeds that give big harvests, but only with steady water and fertiliser. Irrigation is a precondition for HYVs to work.
• Why the Green Revolution worked in Punjab, Haryana and western Uttar Pradesh:
• more than 85% of net sown area is irrigated there
• this assured water let HYV wheat and rice succeed

• result: these states became India's "food bowl"

• Dependence on groundwater (NCERT):

• Wells and tubewells water 76.1% of Punjab's net irrigated area.
• They water 51.3% of Haryana's net irrigated area.

• Result: water tables are falling fast in these states (the Class 8 NCERT also points to falling groundwater in Punjab).

• National picture (Economic Survey 2024-25):

• Irrigated area rose from 49.3% to 55% of gross cropped area between FY16 and FY21 [2].
• Irrigation intensity (gross irrigated area ÷ net irrigated area × 100, which shows how many times the same irrigated land is cropped) rose from 144.2% to 154.5% in the same period [2].
• Punjab, Haryana, Uttar Pradesh and Telangana have high irrigation coverage [2].

4. Sources of irrigation by region

Source	Where it is used	Why it is used there
Canals	North-west plains (Punjab, Haryana, western UP); Indira Gandhi Canal in Rajasthan; deltas of the Mahanadi, Godavari, Krishna and Kaveri	Rivers that flow all year (fed by Himalayan snow) or large reservoirs; flat land and soft soil make it easy to dig canals
Tanks	Peninsular India: Tamil Nadu, Karnataka, Andhra Pradesh, Telangana	Hard rock lets little water soak in; the land has natural hollows; rivers are seasonal, so rain water is stored. Old example: the Grand Anicut (Kallanai) on the Kaveri, built by the Cholas
Wells and tubewells	Northern plains (Punjab, Haryana, UP, Bihar), Gujarat, Rajasthan, Tamil Nadu	Alluvium (soft, loose soil laid down by rivers) holds large amounts of groundwater; in hard-rock areas, water sits in cracks in the rock

5. Pradhan Mantri Krishi Sinchayee Yojana (PMKSY, 2015-16)

• PMKSY is the central scheme to bring some protective irrigation to every farm. Protective irrigation means enough water to save a crop during a dry spell.
• Aims:
• Har Khet Ko Pani ("water to every field"): bring more farmland under assured irrigation
• join up the source, distribution and use of water (from dam or well, through channels, to the field)
• Per Drop More Crop: get more harvest from each unit of water
• bring in water-saving, sustainable practices

• develop rain-fed areas through watersheds. A watershed is the area that drains into one stream; it is treated by checking runoff, raising soil moisture and recharging groundwater.

• Components:

Component	What it does
Accelerated Irrigation Benefit Programme (AIBP)	Funds the quick completion of big and medium irrigation projects
Har Khet Ko Pani	Creates new water sources, repairs and restores water bodies, builds field channels
Per Drop More Crop (PDMC)	Water-use efficiency on the farm through micro-irrigation
Watershed Development	Soil and water conservation in rain-fed areas

• PDMC updates:
• It ran as a PMKSY component from 2015-16 to 2021-22. From 2022-23 it has been carried out under the Rashtriya Krishi Vikas Yojana (RKVY) [5].
• Subsidy: 55% of the project cost for small and marginal farmers and 45% for other farmers [2].
• From FY16 to December 2024, ₹21,968.75 crore was released and 95.58 lakh hectares came under micro-irrigation. That is about 104.67% more than before PDMC [2].
• The Micro Irrigation Fund (MIF), set up with NABARD in 2018, gives states a 2% interest subvention (a cut in the interest rate) on their loans [2].

6. Micro-irrigation: drip and sprinkler

• Micro-irrigation means giving water in small, controlled amounts close to the plant's roots instead of flooding the whole field. It saves about 30-50% of water.
• Leading states: Maharashtra, Karnataka, Andhra Pradesh, Rajasthan and Gujarat.

Feature	Drip (trickle) irrigation	Sprinkler irrigation
How it works	Pipes with small emitters let water fall drop by drop onto the roots	Water under pressure is sprayed through nozzles and falls like rain
Saving	40-70% of water and fertiliser	Less than drip, but more than flooding
Best for	Orchards, vegetables, sugarcane, cotton (row crops)	Uneven land and sandy soils, e.g. Rajasthan, Haryana
Extra benefit	Fertigation: fertiliser mixed into the drip water	No need to level the land; covers large areas

• Why flood irrigation wastes water:
• water spreads over the whole field
• much of it evaporates or sinks below the roots
• result: low water-use efficiency and waterlogging and salinity (salt build-up in the soil) in canal areas

7. Virtual water and water footprint

• Virtual water (term coined by J.A. (Tony) Allan, 1993) is the water used to produce a good. It is "hidden" in the product.
• How trade moves water:
• growing 1 kg of rice in Punjab uses about 3,000-5,000 litres of water
• when India exports rice, it is in effect exporting that water

• result: groundwater from stressed Punjab and Haryana leaves the country inside the grain

• Water footprint (A.Y. Hoekstra, 2002) is the total fresh water used to make the goods a person, firm or country consumes.

• The National Water Policy 2012 asks for benchmarks of water use for different purposes, called water footprints, along with water auditing.
• Policy lesson: grow water-heavy crops in water-rich regions. Move Punjab-Haryana farmers from paddy to less thirsty crops (crop diversification: pulses, maize, oilseeds).

Prelims Hooks

• Agriculture takes 89% of surface water and 92% of groundwater use. Industry takes 2% of surface water and 5% of groundwater.
• Domestic use takes a bigger share of surface water (9%) than of groundwater (3%). Industry is the reverse.
• Wells and tubewells water 76.1% of Punjab's and 51.3% of Haryana's net irrigated area (NCERT).
• India's stage of groundwater extraction = 60.47% (Assessment 2024). Yearly extraction is 245.64 BCM out of 406.19 BCM extractable [3].
• Irrigated area rose from 49.3% to 55% of gross cropped area between FY16 and FY21. Irrigation intensity rose from 144.2% to 154.5% [2].
• PMKSY (2015-16) has four components: AIBP, Har Khet Ko Pani, Per Drop More Crop, Watershed Development. PDMC has been under RKVY since 2022-23 [5].
• PDMC subsidy: 55% for small and marginal farmers and 45% for others [2]. NABARD's Micro Irrigation Fund gives a 2% interest subvention [2].
• Drip suits orchards, sugarcane and cotton and saves 40-70% of water. Sprinkler suits uneven land and sandy soils (Rajasthan, Haryana).
• Virtual water was coined by Tony Allan (1993). Water footprint was coined by Hoekstra (2002). Do not mix them up.
• Trap: tanks are typical of peninsular hard-rock areas (Tamil Nadu, Karnataka), not of the alluvial northern plains, where wells and tubewells lead.

Mains Points

• Farm-led water demand and the coming squeeze (GS-III):
• agriculture uses about 90% of water
• industrial and domestic demand is rising
• NCIWRD's 1,180 cubic km estimate for 2050 is close to the utilisable limit

• so demand management (efficiency, pricing, recycling) matters more than new supply

• Green Revolution trade-off (GS-I/III):

• more than 85% irrigation in Punjab, Haryana and western UP made HYVs succeed
• but heavy use of tubewells, encouraged by free power and paddy procurement, caused over-exploited blocks and falling water tables
• rice exports add to the drain by exporting virtual water

• answer: crop diversification, direct-seeded rice, and pricing that reflects the value of water

• Efficient irrigation as policy (GS-III):

• PMKSY joins supply (AIBP, Har Khet Ko Pani) with demand-side efficiency (PDMC)
• micro-irrigation reached 95.58 lakh ha by December 2024 [2]

• growth needs more subsidy reach for small farmers, MIF loans, and solar pumps

• Regional pattern of irrigation sources (GS-I):

• canals: north-west and the deltas
• tanks: the hard-rock south
• wells and tubewells: the alluvial plains
• this pattern follows relief, rock type and whether rivers flow all year