New study shows flood risk already affects 1.81 billion people

Published: 29 June 2022

In many places of the world, flooding is expected to increase in both frequency and intensity, jeopardizing development agendas of many countries. Researchers from the World Bank, Deltares and UCL found in a new study that almost one fourth of the world population (1.81 billion people) live in locations that are exposed to at least 0.15 meters of inundation depth in a 1-in-100-year flood event. The results of their study were published in Nature Communications this week.

The share of population that is flood-exposed and living under $5.50 per day

Among these people, 170 million are currently living in extreme poverty (less than $1.90 per day), and almost 780 million belong to some level of poverty (less than $5.50 per day). This study describes the magnitude of the issue and underscores the importance of having adequate flood mitigation strategies to prevent the impacts on livelihoods and the setbacks of development progress.

A few of the key findings:

  • Exposure to flood risk is substantial, particularly in low and middle-income countries.
  • Flood risk is global, but the most flood-exposed people live in South and East Asia.
  • When flood exposure and poverty coincide, the risk to livelihoods is most severe.
  • Relying on monetary risk estimates risks overlooking the areas most in need of protection.

Systematic risk mitigation measures are crucial to prevent the loss of lives and livelihoods and reversal of development progress.

The study was led by Jun Rentschler (The World Bank) in collaboration with Bramka Arga Jafino (Deltares) and Melda Salhab (UCL / The World Bank). This study was supported by the Global Facility for Disaster Reduction and Recovery (GFDRR).

Download the study here:
Rentschler, J, Salhab, M and Jafino, B. 2022. Flood Exposure and Poverty in 188 Countries. Nature Communications.

Read the full blogpost (credit World Bank) here.