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Bengal water machine reform offers hope for millions of farmers
Research is providing alternatives to restrictive policies that have limited groundwater use in Bangladesh, where food security challenges remain.

In 2022, CGIAR research produced recommendations for groundwater policy reforms in Bangladesh that could benefit tens of millions of people.
The recommendations have been drawn from extensive CGIAR research into the groundwater-energy nexus, ongoing explorations into solar irrigation under the CGIAR Research Initiative on Transforming Agrifood Systems in South Asia, and emerging CGIAR literature on local irrigation methods—such as the “Bengal water machine”—and their potential for supporting climate change mitigation and adaptation, while ensuring food security.
Bangladesh is among the world’s most densely populated countries and crop production is intensive. Since facing food scarcity around the time of independence in 1971, policymakers have encouraged farmers to cultivate crops during the rainy monsoon season; but also produce a second or even third crop during the dry winter and early summer seasons. Production during these dry seasons has long been supported through policies that have relaxed barriers to the import and installation of irrigation pumps.
Farmers adapted to this context with the invention of the “Bengal water machine”—tube wells using water from aquifers that are recharged on an annual basis by monsoon rains and major rivers. The system has captured 75 cubic kilometres of freshwater over 30 years. Farmers use pumps to extract water and control flooding during the rainy season. Research shows that, when carefully managed, the process can not only aid water conservation efforts, but can also enhance flood control and food security.
Being mindful of differing groundwater recharge rates, government policy has tried to restrict pumping in areas with lower recharge. A lack of reliable information on aquifer levels has since led to blanket bans, even where groundwater is abundant. Farmers in Bangladesh are now bound by mandatory, restrictive groundwater use permits that limit their ability to use groundwater to irrigate. Longer dry seasons compounded by climate change make it harder to produce extra crops, threatening the nation’s food security.
Now, based on CGIAR recommendations, farmers could soon be benefiting from new policies that are tailored to specific areas, based on how much water is available in local underground aquifers. The concept and proposed policies have gained attention both nationally and internationally, with researchers featured in the media.
In parallel, the CGIAR Initiative on Transforming Agrifood Systems in South Asia is investing in options like solar-powered pumps to shift the innovative system towards clean, renewable energy. These are being introduced as on-grid systems where farmers can generate and sell solar electricity when their pumps are not in use.
The integrated approach contributes to national and global goals on food security, sustainable development, and climate change adaptation and mitigation.

Learn more
- CGIAR Initiative on Transforming Agrifood Systems in South Asia
- Publication: The ‘water machine’ of Bengal
- Publication: Adaptation co-benefits of solar irrigation: evidence from Bangladesh
- Publication: The energy-irrigation nexus in Bangladesh: implications of rapid rural electrification on informal groundwater markets
- Opinion: Climate change: put water at the heart of solutions
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