Alternate Wetting and Drying: What’s holding Bangladesh back from a promising irrigation practice?

Rice is the staple crop in Bangladesh, covering about 75% of arable land. Continuous flooding in rice fields is a long-standing practice and widely believed to be essential for high yields. This practice, however, poses a two-fold challenge.

First, flooded rice fields emit large amounts of methane — a potent greenhouse gas. Irrigated rice fields account for around 62% of the country's total methane emissions. Second, this cultivation method exerts immense pressure on groundwater, as most irrigated rice in the country relies heavily on pumped water.

To meet food-security goals while advancing climate and water sustainability, these twin challenges must be addressed without compromising yields. One promising solution is Alternate Wetting and Drying (AWD), an irrigation management practice that intermittently dries rice fields instead of keeping them continuously flooded. 

Research across South and Southeast Asia shows that such irrigation practices can cut methane emissions by 30–70% and reduce irrigation water use by 20–70% without affecting yields.

In Bangladesh, studies suggest AWD can increase farm profits by 7–10%, mainly by lowering irrigation costs, which make up about 30% of rice production expenses. Properly managed AWD also allows deeper root growth, reducing harvest losses and sometimes even improving yields. Moreover, it opens opportunities for earning carbon credits by cutting emissions from one of agriculture's largest sources.

Yet despite nearly two decades of trials since the mid-2000s, AWD adoption remains very low, with fewer than 4% of farmers practising it at scale. The reasons lie in weak incentives, policy gaps, and behavioural barriers.

Weak incentives for farmers to save water

Bangladesh's irrigation is dominated by fixed-cost, serial-based pumping. Pump owners supply water to farmers in scheduled turns for a flat seasonal fee. Because the cost is fixed, farmers tend to draw as much water as possible during their allotted turn. Since continuous flooding is seen as essential for good yields, neither farmers nor pump owners have much incentive to conserve water.

Water pricing and pumping controls are largely absent in agriculture, which consumes up to 88% of all pumped groundwater. Regulations apply mainly to urban and industrial uses, which together consume about 12%. Moreover, irrigation subsidies and the expansion of solar-powered pumps further reduce pumping costs, discouraging water conservation and limiting AWD uptake.

Policy and institutional barriers

Although national policy documents encourage water-saving technologies, AWD has not been mainstreamed into agricultural extension services. In practice, subsidies for irrigation and solar pumps often work against AWD by making water cheaper to overuse.

A prepaid irrigation system introduced in the drought-prone Barind region showed promise: farmers using prepaid cards tended to reduce pumping hours and adopt AWD. However, weak monitoring and limited enforcement stalled wider diffusion. 

Currently, AWD promotion falls under the Department of Environment, which must coordinate with the Department of Agricultural Extension — a collaboration still weak in practice.

By contrast, countries like Vietnam have seen greater success through policy alignment. There, farmers' cooperatives coordinate irrigation schedules, manage pumps, enforce pumping limits, and extension agencies actively train farmers on AWD under clear institutional mandates — enabling widespread adoption.

Structural and behavioural barriers

Beyond technical feasibility, AWD uptake depends on farmer education, land tenure, topography, and soil type. Studies in Bangladesh find higher adoption among farmers with more education, secure land ownership, flatter fields, and access to reliable weather information.

For smallholders, who are often risk-averse, the lack of training and the belief that continuous flooding is "safer" for yields remain major obstacles. Overcoming these barriers requires large-scale training and demonstrations, which usually follow from clear policy priorities.

The way forward

To scale AWD and realise its water- and emission-saving potential, Bangladesh must take a holistic approach. First, AWD should be mainstreamed in agricultural extension programmes, treated not as a niche trial but as a core component of climate-smart rice cultivation. 

Aligning incentives is also critical: irrigation models should be reformed so that farmers and pump owners share the savings from reduced pumping, whether through volumetric pricing, prepaid systems, or command-area incentives, with subsidies targeting pump owners to reward efficiency rather than consumption. 

Collective irrigation governance should be promoted by encouraging the formation and strengthening of irrigation cooperatives, as seen in Vietnam, since past efforts that focused solely on individual farmers or pump owners often faltered once projects ended. Efforts should target high-priority regions, particularly groundwater-depleted and high-cost areas, guided by hydrological and economic data; areas such as Rajshahi, Chapainawabganj, Naogaon, and parts of Chattogram have recently been designated as critically water-stressed, where AWD could be transformative. 

Finally, strengthening monitoring and adaptive learning is essential: continuous evaluation of AWD under diverse agro-ecological conditions will refine guidelines, while robust institutional monitoring will help prevent post-intervention dis-adoption.

Will politics be an obstacle?

Scaling AWD is as much about political will as technical feasibility. Reforming water pricing, extension services, and irrigation business models are all politically sensitive in a developing democracy like Bangladesh.

Encouragingly, Bangladesh Nationalist Party (BNP) has included AWD promotion in its policy priorities ahead of the February 2026 national election, aiming to cut emissions, curb groundwater depletion, and earn carbon credits from agriculture. This could provide a window of opportunity: if such manifesto commitments translate into actionable policies post-election, AWD could finally move from project-based trials to mainstream practice.

However, political commitments must be matched with institutional capacity: the formation of farmer cooperatives, inter-ministerial coordination, extension systems, and irrigation governance all need strengthening. Simply placing AWD in policy documents is not enough.

The case for AWD is compelling: it reduces emissions and water use, raises yields when properly managed, and can earn carbon credits. It could be a game-changing technology in Bangladesh. Yet institutional inertia, misaligned policies, weak incentives, and behavioural barriers continue to stall progress.

With groundwater stress deepening and climate pressures mounting, scaling AWD is no longer optional — it is imperative. The coming years will determine whether political and institutional actors act decisively or allow AWD to remain an under-utilised good idea.

Sketch: TBS

Md Sohel Rana, PhD, is a Senior Researcher (Agricultural Economist), Centre for Development Research (ZEF), University of Bonn, Germany. Email: srana@uni-bonn.de 

Disclaimer: The views and opinions expressed in this article are those of the author and do not necessarily reflect the opinions and views of The Business Standard.