Tackling flooding in Bangladesh in a changing climate

Nearly 60% of Bangladesh’s population is exposed to high flood risk, a higher proportion of the population than in any other country in the world other than the Netherlands, and around 45% are exposed to high fluvial flood risk, the highest figure in the world. Climate change is exacerbating this risk and causing damage with an increasingly high financial and humanitarian cost.

This policy brief examines the physical and socioeconomic factors that make Bangladesh so vulnerable to flooding, particularly in a changing climate, before reviewing how the country has addressed this challenge to date and how it might respond better in the future.

• Bangladesh is highly prone to flooding because of its location in the Bengal Delta and its low-lying, flat topography. Over half of its population is exposed to high flood risk.
• Several factors linked to climate change are increasing the country’s flood risk, including the increasing frequency of extreme precipitation events and more erratic rainfall.
• The magnitude of peak river flow could increase by 36% on average under a high-emissions scenario and by 16% under a low-emissions scenario by 2070–2099 relative to 1971–2000.
• Effective flood policies are ever more important to increase resilience and adaptation and reduce the likelihood of cascading humanitarian and economic impacts.
• Early efforts to address flooding that focused on structural measures such as building embankments have not been fully effective and in places may have made flood-prone areas appear safer than they are, in turn exposing a higher share of the population to flood risk.
• More recent government policies have adopted a ‘living with floods’ approach, using measures such as discouraging settlements in high-risk zones and providing water-resistant construction materials and salt-resistant crops.
• Barriers to implementing more effective flood risk management in Bangladesh include insufficient knowledge about vulnerabilities and local needs; a lack of capacity in local institutions such as the Ministry of Disaster Management and Relief; governance issues; and poor access to funding for investment in adaptation.
• Governance of flood and disaster risk could be improved through needs assessments, more community participation, better coordination between government and non-governmental organisations (NGOs), and between government agencies themselves.