Our award-winning reporting has moved

Context provides news and analysis on three of the world’s most critical issues:

climate change, the impact of technology on society, and inclusive economies.

India faces worst urban flood risk, analysis suggests

by Kyle Plantz | Thomson Reuters Foundation
Thursday, 5 March 2015 16:09 GMT

People walk past partly submerged vehicles on a flooded street in Srinagar after the worst flooding in the Kashmir valley for more than a century. Picture September 15 2014. REUTERS/Danish Ismail

Image Caption and Rights Information

Cities most at risk of river flooding can save billions of dollars by taking precautions now

LONDON (Thomson Reuters Foundation) - Worsening floods in urban areas could cost India billions of dollars and affect a significant portion of the population by 2030, a new online flood risk tool suggests.

As a result of strengthening climate change impacts and a growing population, India tops the list of countries with the most people affected by river floods. About 4.8 million Indians are hit each year at present, but by 2030 that could rise to about 19 million a year, predicts the Aqueduct Flood Analyzer, developed by the World Resources Institute (WRI) and four Dutch research agencies.

Bangladesh ranks second with 3.4 million people affected annually by river flooding today; China is third with 3.2 million. By 2030, Bangladesh could have about 5.5 million affected each year and China about 11 million.

River flooding currently affects 21 million people on average globally each year, causing losses of about $96 billion in GDP on average each year, according to WRI's analysis. Those numbers could grow to 54 million people and $520 billion in GDP affected annually by 2030.

The analyzer estimates potential gross domestic product loss, affected population and urban damage from river floods for every state, country and river basin in the world, said Tianyi Luo, a research analyst at WRI and co-developer of the analyzer.

The interactive tool allows users to choose between different potential combinations of socio-economic development and climate change effects, and adjust the scenario for the number of years that countries provide flood protection.

The adjustments - for most countries, 25 years of flood protection is "a middle of the road scenario" - allows a user to "customize flood protection levels based on his or her experience and knowledge of a specific place," Luo said.


Hessel Winsemius, a researcher at Deltares, a Dutch research organization that partnered with WRI for the analyzer, said the tool's value is that "complex data really becomes alive and becomes available to a non-specialist audience, far beyond the research arena."

"The analyzer really transforms these data layers into actionable information, informing users like governments and businesses which developments in their region are at risk," he said. "This really opens doors to discuss how to achieve this protection."

According to the tool, India has more of its annual GDP exposed to river flooding each year, on average, than any other country. Its current $14.3 billion exposure could increase to about $154 billion by 2030, the tool suggests.

Southeast Asia also could see a significant increase in risk as a result of strengthening climate impacts and changing socio-economic trends, Winsemius said.

Flood risk and efforts to avoid it in particular need to be looked at in growing cities such as Ho Chi Minh City in the Mekong delta and Shanghai in the Yangtze basin, he said.

Results from the tool suggest that climate change is a bigger driver of growing urban flood risk - accounting for about two-thirds of it - than population growth and urban growth itself, Luo said.

Worsening urban flood risk is evident around the world. Floods last September in Kashmir killed more than 270 people in India and 280 people in Pakistan.

In 2011, Thailand suffered an estimated $45.7 in damage and economic losses as a result of flooding along the Mekong and Chao Phraya river basins, including in industrial areas near Bangkok, according to World Bank figures.

"This powerful tool helps us focus our efforts on early flood warning systems (and to guide) resilience building inventions in flood-prone areas to reduce the actual damage that can occur over time," said Erin Coughlan, senior climate specialist for the Red Cross Red Crescent Climate Centre.

Alana Simpson, a senior specialist for the Global Facility for Disaster Risk Reduction of the World Bank Group, said international relief organizations usually have to "answer swiftly" to governments that are seeking solutions for flood-risk prevention, and the analyzer allows them to compile that data in a way that is easy for people to understand.

"One of the challenges in least developed countries is looking at what is the risk today and where the populations are located (alongside) where the flood risk is historically and where it will be in the future," she said.

"We need to get decision makers to visualize what their future is like and what actions they can take today to mitigate the risk in the future," she said.

(Reporting by Kyle Plantz; editing by Laurie Goering)

Our Standards: The Thomson Reuters Trust Principles.