Scientists and industry players have come together to develop an online World Flood Mapping tool to better plan for disasters in the future.
The World Flood Mapping tool is the result of collaboration between UN University’s Institute for Water, Environment and Health in Hamilton, Canada, Google, MapBox an other partners. The tool is free to use and helps users locate gaps in flood defences and responses, and to plan future development of all kinds.
Simple to use, the tool, at https://floodmapping.inweh.unu.edu, requires only Internet access to obtain a flood map at 30-meter resolution — street by street level. An upcoming version for more commercial uses, for example by insurance firms, will offer even more precise building-level resolution.
The tool allows users to adjust variables to help locate gaps in flood defences and responses, and to plan future development of all kinds — for example, where to build or upgrade infrastructure, or develop agriculture. The World Flood Mapping Tool uses the Google Earth Engine combined with decades of Landsat data since 1985 — a vast catalog of geospatial data enabling planet-scale analysis capabilities.
Layers of Landsat information for a selected region and specified timeframe identifies temporary and permanent water bodies while integrating site-specific elevation and land-use data. This produces a detailed map of flood inundation in recent decades, with available overlays of population, buildings and land use, which can be used for community planning, building zoning, insurance assessments and more.
To validate the technology, maps generated in less than a minute using the new tool were compared to documented flooding events in Australia, Bangladesh, Canada, Cambodia, India, Mozambique, Sri Lanka and Thailand (detailed below), with 82% accuracy achieved.
The new tool will also reflect new floods soon after they occur to provide the most up-to-date maps to help assess overall flood impacts and plan for the future. The more detailed version of the tool in development for commercial use will provide resolution at a building-by-building level and incorporate building occupancy data.
And a free flood risk prediction tool for release next year will use artificial intelligence to generate current and future flood risk maps for three climate change scenarios at the city, district, and river basin levels.
The new tool differs from previously available systems in a number of ways, including:
- Improved resolution of inundation maps to 30 meter resolution, enabling analysis at a citywide level
- Focus on the Global South, where data and information gaps are prominent and annual losses due to floods are high
- Improved accuracy of inundation maps using data from multiple satellite sensors
- Improved accuracy and shorter development time of flood risk maps by using AI models
The World Flood Mapping Tool could also potentially guide development of agriculture insurance support for persons living and farming at the subsistence level. Creating this safety net would have far-reaching implications for global development goals and promoting more secure economies and nations.