Irrigation Efficiency in Water Resource Management

Irrigation efficiency measures the proportion of applied water that is effectively used by crops, reflecting both technological performance and management practices. Improving this efficiency is critical for addressing water scarcity, sustaining agricultural productivity and safeguarding ecosystem services under shifting climatic conditions. At the farm level, efficiency gains may be achieved through precision methods such as drip and sprinkler systems, aided by remote sensing, machine-learning models and sub-field water-use mapping. At the catchment or basin scale, however, losses deemed inefficient on-farm may re-enter rivers or aquifers as return flows, supporting downstream users and ecosystems. Consequently, efficiency must be assessed across multiple spatial and temporal scales to avoid unintended consequences such as increased salinisation, reduced ecological flows or exacerbated scarcity in other sectors. Modernisation of irrigation infrastructure often yields higher water-application precision, yet may also drive rebound effects whereby saved water underpins expansion of irrigated area or change of crop types. Policy instruments, water accounting frameworks and basin-wide allocation rules are thus indispensable to translate on-farm gains into genuine resource savings. Globally, integrating hydrosaline balance studies, flow-resilience classification and remote-sensing-driven water accounting supports targeted interventions in arid and semi-arid regions. By coupling technological innovation with adaptive governance, research points to pathways for reconciling food security, ecosystem resilience and equitable water sharing under intensifying demand and climate uncertainty.

Research from Nature Portfolio

Recent studies have harnessed high-resolution remote sensing and machine-learning to generate field-scale crop water consumption maps, revealing that shifting to lower-intensity crops can cut water use by up to 93% and that non-cover-altering practices offer further ~11% savings. These tools provide sub-field guidance to optimise crop selection and irrigation scheduling in water-limited regions. Complementary work using a 35-year dataset spanning streamflow, climate and irrigation extents across major US western river systems demonstrates that irrigation intensification has altered flows beyond climate effects alone. By classifying basin sustainability according to flow and irrigation trends, researchers identified where modern irrigation systems bolster water supply and where inefficient networks exacerbate ecological stress, thereby informing targeted modernisation and basin resilience strategies.

Irrigation Efficiency in Water Resource Management publication trend

The graph below shows the total number of articles in irrigation efficiency in water resource management across all publications each year (not limited to Nature Index journals).

Technical terms

Irrigation efficiency: The fraction of water applied that is taken up and used by crops as intended.

Evapotranspiration: The combined loss of water from soil evaporation and plant transpiration to the atmosphere.

Return flow: Portions of irrigation water that percolate to groundwater or runoff into surface waters after application.

Hydrosaline balance: The accounting of water and dissolved salts entering, stored in, and leaving an irrigated system.

Water productivity: The ratio of crop yield (or biomass) to the volume of water consumed by evapotranspiration.

Basin resilience: The capacity of a river basin to maintain water supply, ecosystem function and societal benefits under stressors.

References

1. Field-scale crop water consumption estimates reveal potential water savings in California agriculture. Nature Communications (2024).
2. Irrigation intensification impacts sustainability of streamflow in the Western United States. Communications Earth & Environment (2023).
3. Hydrosaline balance evolution of an irrigated zone: The case of Lerma basin (Spain, 2004–2020). The Science of The Total Environment (2023).
4. A scale-based framework to understand the promises, pitfalls and paradoxes of irrigation efficiency to meet major water challenges. Global Environmental Change (2020).