By translating state-of-the-art remote sensing data into practical, context-specific advice, WLE and partners are enabling farmers to sustainably improve water productivity and grow more with less.
Around the world, a combination of climate change, population growth and unsustainable production and consumption patterns are increasing water scarcity. It is clear that agriculture – which accounts for approximately 70% of global water withdrawals, mostly for irrigation – must sustainably improve its water productivity (the amount of output produced per unit of water used) if it is to stay resilient in the face of these challenges and strengthen water and food security worldwide. To make better use of available water, however, it is first essential that agricultural water use, especially irrigation, is accurately measured and monitored.
Over the past decade, WLE has been working to improve irrigation monitoring and management by combining field measurements with remote sensing data. Remote sensing data from satellites has revolutionized our ability to monitor irrigation water use. However, as it is rarely made accessible for farmers and irrigation scheme managers, water productivity data from remote sensing does not necessarily translate into improved water productivity. In response, WLE is using state-of-the-art remote sensing data to identify where there may be specific issues with irrigation schemes. This information is then used to define what context-specific interventions are needed on the ground to improve a scheme’s water productivity.
As a result of these targeted interventions, efforts and investments are focussed on the aspects of water service delivery where they will make the biggest difference. This prioritization of funds not only removes the need for extensive, time-consuming ground surveys, but contributes to the rehabilitation and long-term sustainability of irrigation schemes. This marks an important contribution to Sustainable Development Goal 12 on sustainable consumption and production.
Ultimately, this innovation is enabling farmers to make better use of available water. In Koga, Ethiopia, for example, remote sensing was used to generate water productivity indicators for an underperforming irrigation scheme, highlighting where water was being over-exploited. Armed with this information, WLE-supported researchers were then able to provide irrigation managers and over a thousand farmers in the region with tools to assess their irrigation use. These tools – consisting of wetting front detectors and soil moisture sensors – enabled farmers to improve their yields while reducing their agricultural water use, resulting in an impressive 25% increase in overall water productivity. Farmers in the Koga irrigation scheme estimated that their crop yields increased by as much as 20% owing to these changes in water use. There was also a reduction in water-related conflicts among water users.
This work demonstrates that the biggest challenge with using remote sensing for irrigation monitoring is not gathering data, but making that data accessible and useful to farmers. For this to happen, data needs to be translated into straightforward, practical and context-specific advice. This advice also needs to be made easily available to farmers, regardless of their information and communication technology capacity. For example, in Lebanon and Egypt, where most smallholders own smartphones, a smartphone app has been developed to communicate irrigation advice directly to farmers. In places like Koga, however, where the majority of farmers do not own smartphones, project workers teamed up with Water User Associations and irrigation scheme managers to advise farmers. Once again, the importance of context-specific solutions is clear.
Long-term sustainability is another challenge for irrigation. Although projects such as the one in Koga have had remarkable success, the question remains whether water productivity improvements like these can be sustained beyond the life of individual projects.
To address these challenges, irrigation programmes need to build the capacity of farmers to access and use remote sensing data and databases. Without this capacity building, there is a real risk that advances in remote sensing data will have little or no effect on farmers – the very people for whom this data could have the biggest impact. This work has shown that remote sensing data can lead to rapid and significant improvements in agricultural water productivity when it is used to identify issues with, and inform solutions to, irrigation schemes.