[🇧🇩] Smart Flood Management for Bangladesh

[Saif]

Rethinking canal dredging to improve flood management

As another monsoon season approaches, the government’s current canal dredging programme can be a core option for flood preparedness.

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Rethinking canal dredging to improve flood management

Md. Abdullah Al Baky

Overflowing river water washed away part of a coastal dyke in Khulna during the devastating flood of August 2024. FILE PHOTO: HABIBUR RAHMAN

As another monsoon season approaches, the government’s current canal dredging programme can be a core option for flood preparedness. The aim of the programme is clear: restore drainage, reduce waterlogging, and allow floodwaters to recede faster. But the real question is deeper: can canal dredging alone shield Bangladesh from increasingly intense monsoon floods like the 2024 flood? Or does it need to evolve into a broader, nature-based flood mitigation strategy, as seen in countries like Australia?

Although Bangladesh is a deltaic country, over time, both natural (e.g., sedimentation) and artificial (e.g., illegal encroachment) factors have disrupted the country’s natural hydrological system. The current canal dredging programme may smooth out this hydrological system. Fundamentally, the programme aligns closely with what global literature describes as nature-based solutions (NbS)—approaches that “use natural systems…to reduce flood impacts while delivering broader environmental benefits.” However, there are also negative outcomes, such as accelerated downstream flows, destabilised canal banks, and channel instability, arising from excessive canal deepening.

If asked about the success of the canal excavation programme, the answer depends on whether it is treated as isolated dredging or as part of a larger ecosystem-based flood management strategy. The immediate waterlogging problem can be resolved with an isolated strategy, but it does little to address broader flood risks. In ecosystem-based flood management (i.e., NbS), long-term resilience is ensured by reconnecting canals to floodplains, wetlands, and vegetation, thereby allowing the adjacent floodplain to absorb water, reduce peak flows, and regulate naturally. Canal restoration must therefore evolve beyond engineering fixes into a holistic, ecosystem-based flood management approach.

Recent flooding in Australia has accelerated the shift away from reliance on engineered infrastructure alone, driving a transformation towards NbS to manage flood risk. Traditionally, flood management relied on levees, dams, and channel modifications. However, these approaches often accelerated water flow, transferring risk downstream rather than reducing it. NbS, on the other hand, seek to retain water within the landscape by absorbing it, slowing its flow, and spreading it out. In Australia, this approach centres on restoring wetlands, reconnecting rivers with their floodplains, and reinforcing upstream vegetation to reduce runoff. Upper-valley dense vegetation plays a critical role by storing water and weakening its energy, whereas wetlands act as natural reservoirs, absorbing excess rainfall and reducing flood peaks.

Modern flood management is increasingly grounded in the understanding that ecosystems can regulate water more effectively than strict infrastructure. Scientific studies confirm that instead of rapidly draining water away, wetlands absorb and slowly release runoff, attenuating peak flows and easing downstream flood impacts. A study published in Nature shows wetlands prevented up to $625 million in damages during Hurricane Sandy in 2012 in the US. Likewise, mangroves’ contribution to reducing storm surges and associated economic losses cannot be ignored. Vegetated catchments further diminish runoff through natural absorption. Together, these observations confirm that NbS rivals or outperforms grey infrastructure, strengthening resilience while restoring ecosystems. The underlying principle is clear: managing floods effectively means letting the land absorb water, not simply accelerating its flow elsewhere. The question, then, is whether Bangladesh’s canal restoration programme stands up to this principle.

The case for scaling up canal restoration becomes undeniable when viewed through the lens of the Brahmaputra-Jamuna basin, one of Bangladesh’s most flood-prone and hydrologically complex systems. Scientific evidence indicates that this basin is susceptible to severe flooding, bank failures, and large-scale agricultural losses from extreme events. Apart from this basin, the devastation that the other basins can cause is evident from the 2024 floods that affected the eastern basins, including that of Gomati and Selonia, Muhuri, Feni rivers. According to the World Bank, over 12 lakh households were isolated, while total losses reached $1.67 billion, heavily impacting infrastructure and livelihoods. These incidents make the necessity of aligning the canal restoration initiative with NbS crucial.

A critical question, therefore, arises: how can the government align the current canal excavation work with NbS? While deepening seems like the primary focus of this initiative, it should be achieved through variable channel design with pools and shallow sections, resulting in reduced flow velocity and enhanced habitat as was done in the Mary River Catchment Rehabilitation Project in Australia. Equally, maintaining the canals’ natural bends rather than straightening them should be the key to managing the in-channel flow regime, as suggested by the National guidance of Australian Stream Rehabilitation Practice. Beyond excavation, reconnecting canals to the adjacent floodplain, palaeochannels, cutoffs, and wetlands is a vital option for spreading excess water, storing it, and reducing downstream runoff. Additional measures, including restoring riparian vegetation, adopting bioengineering for bank protection, and enhancing upstream infiltration, can further strengthen alignment with NbS principles.

Relying solely on structural flood-protection solutions may fail during extreme events. Our past experiences say so. During the 1988 flood, the Chandpur Irrigation project embankment failed, and the Meghna River shifted by about 550 m, causing catastrophic flooding. Emphasising NbS does not mean replacing engineering infrastructure. Rather, it means a complementary approach as seen in the Victorian Murray Floodplain Restoration Project in Australia. For managing floods in Bangladesh, levees, embankments, and polders will continue to play a critical role. To enhance their effectiveness, incorporating NbS can open a new window of opportunity. So far, the hybrid approach integrating engineered systems with NbS is the most resilient and successful in flood management strategies.

Therefore, it is time to rethink Bangladesh’s canal excavation strategy. Given that Bangladesh’s landscape is different from Australia’s, the programme can be adjusted in line with Australia’s examples and guidelines. Unless canal excavation integrates NbS and moves beyond conventional dredging, achieving effective, sustainable flood management remains unlikely. The principal theme should be working not against water, but rather giving it space, reducing velocity, and applying natural systems.

Dr Md. Abdullah Al Baky, a GIS and remote sensing professional with expertise in fluvial geomorphology, is director of Geospatial Intellect in Melbourne, Australia.​

 

[Saif]

As a flood-prone country, Bangladesh needs stronger early flood warning systems

The world is going through times of high climatic insecurity, exacerbated by unchecked global warming.

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As a flood-prone country, Bangladesh needs stronger early flood warning systems

Kazi Amdadul Hoque

An effective multi-hazard community-based early warning system, which includes disaster risk financing, can save lives and help flood victims cope with financial losses. FILE PHOTO: MD RAJIB RAIHAN

The world is going through times of high climatic insecurity, exacerbated by unchecked global warming. Low-lying countries, such as Bangladesh, find themselves to be especially susceptible to cyclones, floods, river erosion, and more. In Moulvibazar, recent heavy rainfall has caused flooding, leading to irrecoverable crop losses. Although timely adaptive measures have made Bangladesh adept at cyclone precautions, rescue efforts, and makeshift shelters, early warning and response systems for floods have continued to fall short of expectations. According to a World Bank report in 2020, Bangladesh tops the list of flood-prone countries globally, with an estimated 20 percent of its land area vulnerable to submergence. Additionally, around 60 percent of the country’s population is exposed to high flood risk, more so than in any other country in the world besides the Netherlands.

The population density in Bangladesh is 1,319 per square kilometre, and as per the World Bank’s April 2026 Bangladesh Development Update, the country’s poverty rate increased to 21.4 percent in 2025 from 18.7 percent in 2022, adding 14 lakh more poor people in 2025. Meanwhile, Bangladesh’s Human Capital Index score of 0.46 reflects gaps in education, healthcare, and skills, which also limit communities’ adaptation capacity.

The northern areas of Bangladesh, such as Gaibandha, Kurigram, and Chilmari, are in close proximity to major rivers such as Brahmaputra, Teesta, and Jamuna. In 2022, the north and north-eastern regions of Bangladesh were hit by unprecedented flooding, leading to the loss of 12 lives and impacting more than 70 lakh people.

In 2024, flash floods in the country’s east destroyed 339,382 hectares of crops and displaced over 500,000 people. According to a 2021 World Bank report, annual losses incurred by floods in Bangladesh amount to around $2 billion.

Despite extensive data on the issue, early warning systems are still not intensive or community-centric. As of now, demarcated gauge lines, handled by the water resource authorities, are in place to measure dangerous levels of water flow. When water levels threaten to reach or cross these lines, a warning goes out to state that flooding is possible in surrounding areas. What often goes unnoticed, however, is that these installations are sometimes quite far from the villages. Due to topographical diversity, there is hardly a way to discern when and at what speed the water level will hit the villages, located some distance away from the water level gauges. In Bangladesh, hydrological models for an effective early warning system suffer from a lack of upstream data.

According to one study including respondents from Sirajganj district, during 2015-2020, 71.81 percent of households didn’t receive an early warning for flooding. Of the 28.29 percent which received early warning, 82.99 percent households responded by taking preparedness measures.

While early warnings are provided over radio and speaker announcements on regional and union scales, confirmed information on a community or village level is still out of reach. Simply calling for evacuation is often not enough. The ultra-poor residents of these areas spend years saving up for their homes, fields, and livestock. When they hear of a possible evacuation plan, they think of all the losses that await them. Savings and assets go underwater, and they become aid-dependent. However, when aid is discontinued, they do not have any source of income left. Even loans are hard to come by without any assets to show. More often than not, these victims are confused or in denial as to whether evacuation is indeed required.

Decentralising early warning systems

A 2019 United Nations Office for Disaster Risk Reduction (UNDRR) report stated that investment in early warning systems could yield a tenfold return and help avoid losses, save lives, and enhance socioeconomic resilience.

We need to look at our early warning systems through a tech-forward lens. Incoming cyclones or floods should be trackable using mobile phones, satellite images, and waterflow systems. Villages can be assigned colours to signal levels of danger and safety. Each union has a local government information centre that could serve as an early warning hub for that community.

Instead of waiting to distribute aid during floods, disaster risk financing can be pushed for and demanded early on. This will not only reduce pressure on post-disaster aid but also help people innovate their own solutions to deal with the crisis.

Effective multi-hazard early warning systems

Multi-hazard early warning systems are only effective if they actually reach and are actionable by those who need them. Early warning systems convey critical information on potentially hazardous events and can yield the highest benefit-cost ratio of any adaptation investment. As per a 2019 report by the Global Commission on Adaptation, a 24-hour warning for an imminent storm or heatwave can cut the resulting damage by 30 percent, and spending $800 million on such systems in developing countries would avoid losses of $3-$16 billion per year.

It is evidenced that loss of life can be reduced if there is better uptake and understanding of necessary actions, as well as better flood forecasting.

A community-based approach is cheaper than a centralised system. While a central system is crucial, balancing the approach with people’s engagement and the best technology available can make it all the more beneficial.

An effective multi-hazard community-based early warning system with engagement from the community, civil society and private sector is needed. Finally, the benefits will accrue only if early warnings lead to early action, which can very much depend on the credibility and available lead time of the warning information.

Kazi Amdadul Hoque is a climate and social action practitioner.​

 

[Saif]

We need to rethink how we respond to haor floods

In the haor basin, floods have a way of sneaking up on you.

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We need to rethink how we respond to haor floods

Altaf Russell

Flooded fields result in fewer workdays and uncertainty for those working the fields and the existing labour shortages and rising costs exacerbate the problem. Photo: STAR

In the haor basin, floods have a way of sneaking up on you. They often come overnight with sudden currents that fully submerge ripening paddy, turning harvest into a race against rot. In late April and early May, continuous rain and hill runoff from Meghalaya pushed water into Netrokona’s beels and Sunamganj’s lowlands, drowning ripe and semi-ripe Boro and leaving harvested grains to be spoiled due to a lack of sunlight. What followed later was a brutal arithmetic: labourers refused to work in deep water, machines could not operate in waterlogged fields, and whatever could be salvaged had to be dried quickly or sold wet at a discounted price.

This is not merely a regional inconvenience; it has deep implications for the national economy.

Reuters reports Bangladesh may face a rice shortfall of over 200,000 metric tonnes after pre-monsoon rains and upstream inflows damaged the main crop in the northeastern haor wetlands, with more than 46,000 hectares of standing crop submerged. Boro harvested in April and May supplies roughly 55 percent of national rice output, and the haor belt is central to that supply. Farmers have already reported selling paddy at Tk 650-Tk 800 per maund (37.32kg) while production costs are far higher.

A 2022 study found that flood exposure reduces per-capita income and pushes households to adjust expenditures in ways that are developmentally corrosive, especially with cuts to education and health. The study explored why the haor shock travels far beyond the flooded field using the Household Income and Expenditure Survey (HIES) 2016-17 of Bangladesh Bureau of Statistics (BBS). There was a “spillover” effect too, according to the study, where households that did not self-report flood damage but lived in government-identified flooded upazilas experienced income losses comparable to, or larger than, self-reported flooded households.

We can see those spillovers in the haor right now. Flooded fields result in fewer workdays and uncertainty for those working the fields and the existing labour shortages and rising costs exacerbate the problem. According to a report in by this daily, even traditional emergency arrangements, like offering a share of the crop to anyone who harvests during disasters are failing as risk rises and lightning fear grows. Meanwhile, post-harvest bottlenecks continue to spread the shock: the directorate general of food has discussed using private rice mills and warehouses for drying so procurement and milling do not stall. These are the mechanics of spillover: disrupted value chains, delayed payments, and shrinking local commerce.

Spillover also moves through livestock, which is why “crop loss” is an incomplete metric. Rotten straw and fodder shortages can follow crop loss, forcing farmers to consider distress sales of cows after losing grain and straw. Farmers calculating debts, considering cattle sales, and fearing exclusion from aid lists—signs that the shock is turning into a balance-sheet crisis at household level. The HIES evidence shows why that matters: households cope through asset depletion and reduced human-capital spending, converting a climate event into long-term poverty.

Targeting relief is where spillovers are often missed. Prothom Alo estimated that nearly 53,000 hectares of boro across five districts were destroyed and about 230,000 farmers affected, while assistance depending on lists still being verified amid fear of genuine victims being left out. This is precisely the policy risk our research flags: when identification relies on incomplete reporting, we undercount indirect victims and misallocate support. In a haor economy where sharecropping and seasonal labour are common, the “affected” category must include people whose income falls because the market around them stalls, not only those whose plot was submerged.

Bangladesh has strengthened one crucial capability that can reduce such losses: anticipatory action. ReliefWeb reports that the Flood Forecasting and Warning Centre (FFWC) issued a seven-day outlook on 23 April indicating high flash-flood risk in the northeastern haor basin from 28 April onward, triggering preparedness measures. Reports also noted that multiple rivers were flowing above the danger level and warned that conditions could worsen and spread to new areas over the following days. Early warning is no longer the missing piece; turning warning into protection is.

So, what would an economy-minded flood response look like?

First, treating post-harvest rescue as a public good by expanding mobile dryers, raising community drying floors, and having emergency procurement that pays a fair, quality-adjusted price so farmers are not pushed into distress sales.

Second, designing relief around livelihoods, not only land ownership. It can include sharecroppers and wage labourers in cash support and the list can be verified through field checks to reduce exclusion.

Third, protecting human development during recovery. Floods displace health and education spending so temporary school fee waivers, health outreach, and targeted top-ups can prevent a short shock from becoming an intergenerational setback.

A fourth step could be shock-responsive finance. Reports capture a familiar chain of crop loss, debt calculation, and talk of selling cattle or mortgaging land. We should formalise relief beyond one-off grants through automatic rescheduling of agricultural loans in declared flash-flood windows, low-interest bridge credit, and pilots of area-based crop insurance that pay out when FFWC triggers are met. Early warnings should unlock early liquidity, not only early messages.

Finally, we must stop manufacturing waterlogging through poor infrastructure choices. In the 2022 study on economic impact of monsoon flood, it was noted that roads, railways and embankments can interrupt floodplain connectivity and turn a natural hydrology into human-induced harm; some other analysis echoes this through the lens of blocked drainage and inadequate culvert openings. “Living with water” in the haor requires restoring flow pathways, enforcing cross-drainage standards, and aligning development with wetland ecology rather than against it.

Bangladesh will always live with water. The question is whether we will keep paying the same hidden bill: lost incomes in flooded villages, lost workdays in nearby towns, and lost futures when families cut health and education to survive. The haor flood of 2026 is an economic lesson in spillovers: if we plan for the spillover, we protect more than a crop, we protect the country’s development trajectory.

Altaf Russell is a PhD researcher in economics at the University of Glasgow.​