Our first round of irrigation lasts two days and there is usually plenty of water, so we irrigate non-stop. But during the second and especially third and final round of the season, water is much more limited. Water for the household we have to get from the well, and we have to deepen it in dry years

Pham Thi Tuyet, a coffee farmer in Dak Lak, aptly describes how farmers in Vietnam’s Central Highlands are experiencing the consequences of groundwater depletion. WLE scientists are trialing solutions for more sustainable water use, including a method for recharging farmers’ wells. A system of collection canals and filtering tanks captures rainwater and directs it into groundwater reserves, thus building resilience to water scarcity.

Likewise in sub-Saharan Africa, improving farmers’ access to irrigation helps them adapt to changing rainfall and growing water scarcity. Investments in agricultural water management technologies could double, or even triple, yields of crops that are currently rain fed, and irrigated areas could be sustainably expanded by 15 million hectares. But, many past investments in irrigation have been fraught with failure, which is why scientists recommend developing viable, sustainable and inclusive business models for small-scale irrigation.

Which is exactly what another team of researchers has done for Ethiopia, where only 14% of the population are connected to the electricity grid. A set of newly developed solar irrigation business models, coupled with maps that identify best bet zones for irrigation, seek to encourage investments in this green and climate-smart technology. By considering different mechanisms of adoption, payment, financing and governance, the models lay out how to make access to solar technology more inclusive, especially of the poorest farmers.

But there are challenges too: solar-powered pumps are essentially free to use, which implies a risk of over-pumping and groundwater depletion. A number of safeguards have been proposed, including creating financial incentives for responsible use via the energy sector. A tool to assess environmental flows in rivers globally can also help decision makers assess how much water is being replenished and thus the limits for sustainable abstraction.

Finally, with climate change likely to have increasing impacts on water availability—and in turn food production and smallholders—scientists have set out to determine how climate resilience can be quantified, measured and achieved. With climate change impacts intensifying, developing and sharing attractive, viable solutions to safeguarding water on a large scale is increasingly urgent.

WLE’s partners in this work include IWMI, IFPRI and ICRISAT.