Bangladesh is one of the most vulnerable countries to the effects of climate change, in part due to its geographical positioning and low-lying land. The geography and other environmental elements have also made Bangladesh historically prone to flooding, especially during the monsoon season, from early July to late September. The regular flooding already often comes with devastating consequences, and climate change is only making the situation worse with each passing year.
Over the past sixty years, the average temperature in Bangladesh has risen 0.7-1 degree Celsius, bringing with it an increase in storm events, more floods, and heavier rainfall. A warmer climate also contributes to the rising sea level. The global mean sea level rose by 4.4 millimeters per year for the last eight year– over twice the rate of sea level rise throughout the 1990s and early 2000s. In total, sea levels are expected to rise to a staggering 1.5 meters for the Bangladesh coastline within the next eighty years. Climate change is also wreaking havoc on the seasons, leading to hotter, longer summers, warmer winters, and extended monsoon seasons with a higher-than-before total volume of rainfall.
As climate changes make flooding a more significant issue for Bangladesh, the immediate need for cracking down on flood management and building climate resilience is clear.
In rural areas of Bangladesh, residents have historically adapted to the seasonal flooding patterns. However, this is becoming less sustainable with each passing monsoon season. Land is waterlogged for months at a time, longer periods than ever before. This has deadly implications for local populations of farmers, who rely on the yield of their land for their livelihoods. As floods become more frequent and land is inundated for longer periods of time, the soil becomes saltier over time. Over the past thirty-five years, there has been a 26% increase in soil salinity. This is a stark problem, as saline-contaminated soil is hostile to many crop varieties, including the regional staple crop: rice. In addition, as the sea level rises, more and more land is encroached by seawater. As of 2009, already about 13.5% of arable land was affected by encroaching seawater, and it’s projected that almost half of productive land (40%) in Bangladesh is at risk of inundation over the next century. In general, tidal flooding is more of a threat than ever, and climate change-fueled cyclones make villages even more vulnerable to flooding by destroying embankments and other flood infrastructure. As the pressures of flooding and waterlogged land mount, many are pushed to migrate from rural areas in the short- and long-term. As the rising sea level contaminates the land and water, there are also significant health risks, including hypertension and skin diseases, and a struggle to find clean drinking water as people from villages, often women, have to venture further to find uncontaminated freshwater sources.
Flooding in Dhaka is also becoming worse than before in terms of depth, total flooding area, and duration. While Bangladesh used to have a large and extensive natural canal system to help mitigate urban flooding, that’s largely gone today due to rapid urbanization and improper management and oversight. Human activities like the filling of canals and low-lying areas, surface paving, and solid waste dumping have exacerbated the flood risk. This has left Dhaka and other cities more vulnerable to the water-logging that occurs when runoff from heavy rainfall overwhelms the capacity of the drainage system. Urban residents of Bangladesh are feeling the negative repercussions of more frequent and disruptive flooding, including health problems arising from the contamination of drinking water and risks to critical public infrastructure like service provision facilities and communications systems.
People in both rural and urban areas of Bangladesh have been working to cope with and adapt to this reality of frequent, prolonged flooding in a variety of ways. In villages, some farmers have shifted from crop growing to aquaculture– growing shrimp or capturing, feeding & selling crabs– while others have developed ways to farm on top of water by using floating seedbeds made up of water hyacinth and bamboo. Scientists have also been looking into creating crop varieties that can grow in the saline-contaminated soil. The Bangladesh Rice Research Institute, for example, has created a new rice variety that can tolerate water that is three times saltier than what the regular rice varieties can survive in. Meanwhile, in Dhaka, Bangladeshi architect Rafiq Azam has worked toward making parts of the city more resilient to the climate by converting urban parks into revitalized parks that can also collect and store runoff from rainwater. These examples highlight the kind of innovation and adaptation that is necessary to cope with our changing climate.
On a larger scale, Bangladesh has also taken some significant and admirable steps in working to mitigate flood risks across the country, such as the implementation of various climate action initiatives. These include community training and education campaigns, preparatory actions, and investments in infrastructure. For example, volunteers are trained to prepare for cyclones by using warning flags and loudspeaker announcements and evacuating households in flood-prone areas. In some villages, people have worked to form a system to fight catastrophe, utilizing satellite images and notification-based warning systems. These actions are significant progress toward building community resilience, a cornerstone of adapting to and facing catastrophic climate events.
Unfortunately, these measures are still far from enough. Bangladesh needs to develop climate-resilient infrastructure on a large-scale. For instance, there needs to be significant investment in the drainage system in urban areas: improving general maintenance, implementing routine cleaning, devising better technology to reduce solid waste and improve management, etc. This also calls for coordination and possibly reorganization of the various institutional entities that influence elements of the drainage system, waste, and sanitation. There also needs to be more work in developing infrastructure to help divert or temporarily collect rainwater runoff, like Rafiq Azam’s dual-purpose water-catchment parks. Some ideas for this include green roofs, permeable alternatives to paving, and creating more bodies of water or other spaces to act as retention and detention ponds. In rural areas, there needs to be a reassessment of the efficacy of flood infrastructure and exploration of other ideas to reduce the flood risk. One such idea is to actually allow for flooding in certain areas, letting the natural flow of water and sediment take its course and avoid risks such as the sinking of land in polders (one type of flood infrastructure used in villages).
In general, to cope with and minimize the risks and damage of worsening floods, Bangladesh must adapt to its changing climate and build resilience through community and innovation on a national scale. The hopeful part is that we are already starting to see examples of this in both rural and urban Bangladesh.
Tanzilla Purnota graduated from University of California-Berkeley in May 2021 with a Bachelor's in Molecular and Cell Biology (emphasis in Immunology) and a Minor in Public Policy. She is passionate about climate justice, public health and policy, and human biology. During her free time, she enjoys writing across a wide variety of genres and styles, reading about the world, and getting out into nature.
