By 2030, up to 15 million people and $177 Billion USD in urban property will be affected by annual coastal flooding and an additional 132 million people and $535 Billion USD will be affected by riverine flooding, the World Resources Institute (WRI) reports (Aqueduct Floods Tool).

Floods are more intense as a consequence of climate change, development in high-risk zones, and land subsidence from the overuse of groundwater. Using its “Aqueduct Floods” tool, World Resources Institute calculates that by 2050, the numbers are predicted to be “catastrophic”, with a total of 221 million people at risk, with cities bearing the cost of approximately $1.7 Trillion USD annually. Developed in 2014 with consortium of data partners, including Deltares, Amsterdam’s Institute for Environmental Studies, Utrecht University, and the Netherlands Environmental Assessment Agency, the tool also suggests that investment in flood protection infrastructure returns significant benefit. For instance, every $1 invested in flood protection infrastructure in India results in $248 in avoided damages and a 50 percent decrease in future risk.
Charlie Iceland, Director of water initiatives at WRI, told OOSKAnews that “even relatively modest efforts to increase flood protection levels could yield very significant benefits. For example, if Tanzania were to increase its riverine flood protection levels to guard against a 1-in-10-year flood instead of a smaller 1-in-5-year flood (the amount of flood protection we estimate they currently have), this would result in avoided impacts on $79 billion worth of GDP between now and 2100, avoided impacts to 74 million people, and benefits of about $20 for every $1 spent".