What is water-use efficiency? Describe the role of micro-irrigation in increasing the water-use efficiency.
Approach · directive: “what / describe”
What it asks · Define water-use efficiency and explain how drip and sprinkler systems raise it.
The question has 2 parts — answer each
- What is water-use efficiency: define it
- Describe the role of micro-irrigation (drip and sprinkler) in increasing water-use efficiency
Open with · India uses most of its freshwater for irrigation, yet gets less crop from each unit of water than many other countries; efficiency is the answer to a shrinking water budget.
Cover
- Meaning: water-use efficiency is crop yield per unit of water used, often called more crop per drop, and judged at field, farm or project level.
- Where it is lost: in canals and channels through seepage and evaporation, and in the field through runoff, deep percolation and excess flooding in traditional surface irrigation.
- Drip: delivers water drop by drop to the root zone, cutting evaporation, runoff and weed growth and letting fertiliser be applied with water (fertigation).
- Sprinklers and micro-sprinklers: spread water like rain with controlled amounts, suitable for uneven land, light soils and many field and orchard crops.
- Gains: substantial water and energy savings, higher yield and quality, more area under irrigation from the same source, and less waterlogging and salinity.
- Constraints: high upfront cost for small farmers, clogging, maintenance and power needs, delays in subsidy; cereals such as paddy are hard to cover.
- Support: the Per Drop More Crop component of PMKSY (from 2015-16) provides subsidy, and NABARD's Micro Irrigation Fund (Rs 5,000 crore, created in 2018-19) helps States top up incentives for coverage.
Close with · Water-use efficiency must rise with micro-irrigation, better canal management, crop choice matched to water availability and efficient pricing of water and power.
Add value (verified)
- PMKSY guidelines list improving on-farm water-use efficiency to reduce wastage among the scheme's objectives. ↗“Improve on-farm water use efficiency to reduce wastage and increase availability both in duration and extent”
Question: UPSC's CS (Main) 2016, GS Paper III — paper ↗. Approach: Minimalist IAS, checked 30 Sept 2026 (how we verify) — UPSC publishes no model answers. ·
Model answer · 256 words (UPSC limit 200) · Minimalist IAS
Irrigation takes most of India's freshwater, yet each unit of water yields less crop than in many countries. Water-use efficiency is the ratio of crop output to the water actually used, popularly 'more crop per drop', measured at field, farm or project level.
Where water is lost
- Conveyance losses: seepage and evaporation from canals and field channels.
- Application losses: runoff, deep percolation and excess flooding in traditional surface irrigation, so only part of the water reaches the root zone.
- Efficiency rises when these losses fall and when each unit of water produces more yield.
Role of micro-irrigation
- Drip: delivers water slowly to the root zone through emitters, cutting evaporation, runoff and deep percolation, suppressing weeds, and allowing fertigation, so nutrient use improves too.
- Sprinklers and micro-sprinklers: spread controlled amounts of water like rain, suited to uneven land, light soils and many field, vegetable and orchard crops.
- Gains: substantial water and energy savings, higher yield and quality, more area irrigated from the same source, and less waterlogging and salinity.
- Support: the Per Drop More Crop component of PMKSY (2015-16) subsidises systems, with improving on-farm water-use efficiency a stated objective (since then, a Rs 5,000 crore Micro Irrigation Fund was created with NABARD in 2018-19).
- Constraints: high upfront cost for small farmers, clogging and maintenance, power needs and delayed subsidies; cereals such as paddy are hard to cover.
Micro-irrigation is the quickest route to higher water-use efficiency, but it must go with better canal management, crop choice matched to water availability, and rational pricing of water and power.
Written by Minimalist IAS from facts checked at source (how we verify) — a little fuller than exam length, so every part of the question is covered; in the hall, keep the structure and trim the detail. UPSC publishes no model answers: compare your structure and coverage with this, then write your own.