Human settlement in the world’s riskiest flood zones increased 122 per cent since 1985, according to a World Bank report. This had made a lot more people vulnerable to water disasters from climate change. The study authors looked at the settlement extent and expansion using satellites instead of population. They found that the world’s overall built-up regions grew 85 per cent from 1985 to 2015 and a growth of 80 per cent was seen for the safest areas.
According to Jun Rentschler, lead author of the study, “...as a nation grows a bit wealthier, there’s a change from rural to urban and people leave the country to go to cities, which are often near waterways that flood in places”. She further stated that initially one would expect to settle in a safe space but as the city expands, it is more likely to grow into areas which were previously avoided, flood zones for instance. The study found that the problem is driven by middle and low income countries. Richer countries like the US and parts of Europe are seeing more growth in safer areas as compared to flood prone ones.
As per the study report, Dar es Salaam in Tanzania is a poster city for this problem. It bloomed from a fishing village of about 83,000 people in 1950 to more than seven million people now. China and Vietnam both saw their settlement extent more than tripling in the past 30 years, increasing far more than their dry land areas. On the other hand, the US saw dry settlements increase 76 per cent and the highest flood settlements go up only 46 per cent.
Other countries with more dry settlement than ultra wet include France, Sweden, Japan, India and many more. The study further added that populations growing into flood zones doesn’t mean climate change isn’t a major problem, rather they are intertwined. Appropriate development policies and smarter urban planning, can prevent people from moving into these risky fringe areas of cities.