(GIST OF KURUKSHETRA) Water Use Efficiency Ensuring Water Sustainability

(June-2023)

India has about 18 percent of the world’s population but only 4 per cent of the world’s water resources (NITI Aayog Report, 2017).
With an ever increasing population, to support the food requirements of more than 1.35 billion people, irrigation water demand is increasing.
Rapid urbanisation and industrialisation are also taking a heavy toll on the overall water demand scenario. As a result, the gap between water demand and availability has been progressively increasing.
SDG target 6.4 addresses water-use efficiency and water stress, aiming by 2030, to ‘substantially increase in water use efficiency across all sectors and ensure sustainable withdrawals and supply of freshwater to address water scarcity and substantially reduce the number of people suffering from water scarcity’.

In general, the term efficiency is used to quantify the relative output obtainable from a given input. Water use efficiency is the ratio between effective water use and actual water withdrawal. In India, a major chunk of water usage is for agricultural purposes, and a small per centage is for drinking and domestic purposes. Hence, even a small percentage saving of water in agricultural usage will have a significant impact on water availability for drinking and domestic purposes.
Enhancing water use efficiency in every sector of water use including irrigation, is, thus, crucial and imperative for sustaining life faced with the challenges posed by climate change in the water sector in the present times.

India is an agrarian country, being one of the top producers of several crops such as wheat, rice, pulses, sugarcane, and cotton globally. Agriculture is also the source of livelihood for about 58 per cent of India’s population.
Referring to the use of water in irrigation, efficiency may be defined in various ways, depending on the nature of the inputs and outputs to be considered.
Water Use Efficiency (WUE) in irrigation is the per centage of total applied water that is stored in the soil and available for consumptive use by the crops. Some water is lost in conveyance, distribution, and application in the field.

Micro Irrigation:

The WUE in micro-irrigation including drip irrigation is as high as 80-95% in comparison to only 30-50% in conventional flood irrigation.
The micro-irrigation techniques also help in reducing water logging, fertiliser usage, labour expenses and other input costs and in enhancing agricultural productivity and farmers’ income besides sustaining soil health.

Mulching:

Mulching helps in increasing WUE by controlling water losses by evaporation from the plant root zone.
A mulch is a material spread on the top of the soil – plastic sheets, organic material.
There is about 10% water saving from the use of mulch materials in agriculture.

Drought-Tolerant Crops:

Growing crops that are appropriate to the climate of the region also helps in getting more crops per drop.
The ICAR has developed several drought-tolerant short-duration crop varieties that suit different agro-climatic regions of the country for judicious use of water.

Reduce conveyance losses by lining channels or preferably, by using closed conduits.
Avoiding mid-day sprinkling reduces evaporation.
Reduce run-off and percolation losses due to over-irrigation.
Select the most suitable and marketable crops for the region.
Use appropriate insect, disease and parasite control.
Apply manures and green manures where possible and fertilise effectively.
Apply weed control measures.
Practice soil conservation for long-term sustainability.
Irrigate in the exact amounts to prevent water deficits, taking into account weather conditions and crop growth stages.

The Bureau of Water Use Efficiency (BWUE) will be a facilitator for the promotion of improving water use efficiency across various sectors namely irrigation, drinking water supply, power generation, industries, etc., in the country.

Enhanced water use efficiency through persistent and concerted efforts of individuals, groups and associations of people, and the Government implementation agencies and institutional mechanisms will go a long way in effectively coping with the challenges posed by climate change and an ever-increasing population on available water resources and will result in optimum and efficient utilisation of precious water, thereby adding to enhanced productivity, prosperity, and sustainability.