Flood Protection by Mangroves Saves $855 Billion Globally, Report Finds

In a new report, researchers estimate that the economic value that mangroves provide as protection against flooding amounts to about $855 billion globally.

The report, led by researchers at the Center for Coastal Climate Resilience at University of California, Santa Cruz, utilized advanced flood risk modeling over around 700,000 kilometers (434,960 miles) of subtropical coastlines and 121 countries to evaluate the value of mangroves.

The results, which were published in the The Changing Wealth of Nations 2024 report by the World Bank, revealed that even with declining mangrove cover in the face of coastal development and agriculture, the economic value of mangroves has continued to increase since 1996. According to the report, the value of mangrove forests based on their flood protection abilities increased $130 billion from 1996 to 2010, then increased another $502 billion from 2010 to 2020.

Globally, the researchers determined that mangroves save around $855 billion through flood protection as of 2020, with the highest monetary value from mangroves found in China, Vietnam, Australia, the U.S. and India.

“The results are clear: Mangroves play a critical role in reducing flood risks and should be viewed as valuable natural assets,” Pelayo Menendez, co-leader of the research, said in a statement. “They offer cost-effective protection to coastal communities and support national wealth by preserving lives, livelihoods, and infrastructure.”

As explained by the National Oceanic and Atmospheric Administration (NOAA), mangroves, or mangrove forests, are made up of trees and shrubs growing along coastal waters in tropical and subtropical regions, where temperatures don’t drop below freezing. They thrive in low-oxygen soil and can even grow in salt water. 

In a 2020 study (co-authored by Menendez and Michael Beck, director of the Center for Coastal Climate Resilience and an author of the research in The Changing Wealth of Nations 2024), researchers determined that without mangroves, 15 million more people globally would experience flooding every year. The size, shape and density of the trees and the extent of mangrove forests help reduce wave impacts, and their roots stabilize soil to prevent erosion.

Mangroves are not just beneficial for their flood prevention benefits. As Conservation International reported, one square mile of mangroves can store carbon emissions equivalent to the annual emissions from around 90,000 cars on the roads.

According to The Changing Wealth of Nations 2024 report, the rate of global mangrove loss decreased from 2010 to 2020 to about 0.66%. While the total was small overall, some countries experienced major rates of decline of mangrove forest cover of more than 10%, including Saudi Arabia, Taiwan, Sudan, Pakistan and Jamaica. 

Further, a 2024 report from International Union for Conservation of Nature (IUCN) revealed that more than half of global mangrove ecosystems could collapse by 2050, presenting higher threats from flooding and an increase in emissions from the lost carbon storage.

The new report in the latest edition of The Changing Wealth of Nations reveals how important mangrove preservation will be now and into the future.

“Protecting and restoring mangroves isn’t just good for the environment — it’s a smart economic choice,” Beck said in a statement. “These ecosystems provide invaluable services that help build resilience against the growing threats of climate change.”