Study highlights the benefits of mangroves for reducing property damage during hurricanes

October 15, 2025 by Mike Peña, University of California – Santa Cruz

Collected at: https://phys.org/news/2025-10-highlights-benefits-mangroves-property-hurricanes.html

A new study led by the UC Santa Cruz Center for Coastal Climate Resilience (CCCR) and East Carolina University (ECU) has found that mangroves significantly reduced storm surges and property damages during Hurricanes Irma in 2017 and Ian in 2022.

In collaboration with the catastrophe risk modeling firm Moody’s RMS, the team used industry models to price the mangrove benefits during these hurricanes at $725 million and $4.1 billion, respectively.

The study, published in the journal Cell Reports Sustainability, also assessed the expected benefits of mangroves for storm surge protection at $67 million annually in southwestern Florida’s Collier County.

These natural flood defenses are especially important economically in Florida, with its extensive coastline, expensive coastal properties, extreme events, and some exceptional stands of mangrove forests still remaining.

Overall, the study found that mangroves reduce flood losses for coastal homes built inland of the trees. But in some locations, especially for properties in front of mangroves, the team found that properties actually face higher damages due to mangroves.

With their unique aerial root systems, mangroves thrive in marine environments because they can filter saltwater into freshwater. In Florida, an estimated 600,000 acres of mangrove forests contribute to the overall health of the state’s southern coastal zone and beyond, according to the state’s environmental protection department.

The study—a collaboration between CCCR, ECU, Moody’s RMS, and The Nature Conservancy—is the first to value the benefit of mangroves using catastrophe risk industry models.

“In this collaboration with the risk-modeling industry, we show the value of mangrove forests in reducing property damages from storm surges every year,” said study lead author Siddharth Narayan, a recent CCCR research fellow.

“Similar to how salt-marsh wetlands from New York to North Carolina reduced damages during Hurricane Sandy, coastal properties in Florida avoided anywhere between 14 to 30% in surge losses during Hurricanes Ian and Irma due to mangroves acting as natural defenses.”

Now a professor of coastal studies at ECU, Narayan hails from Chennai, a tropical coastal city in South India where he completed his bachelor’s in civil engineering. At UC Santa Cruz and UC Santa Barbara, he focused on coastal adaptation and nature-based solutions.

Nationally, storm surges from tropical cyclones and hurricanes cause billions of dollars in coastal property damages every year. However, natural ecosystems such as mangrove forests can, by their presence on these coastlines, modify storm surges and affect property damages, the study states.

There is growing awareness that mangroves are an important part of storm defenses, and the study aims to increase understanding of when, where and how properties benefit from the effects of mangroves on storm surges.

“Mangroves provide many benefits to communities, and it is particularly important that we used a risk industry model to put a price on their flood protection benefits,” said CCCR Director Michael Beck, the study’s senior author. “Like it or not, we only protect what we value, and this is doubly true if it should influence the cost of insurance.”

Further, Beck noted, “The results of these industry models show the real benefits of conserving Florida’s mangroves for property protection and the real costs of choosing to develop in front of these natural barriers.”

Other co-authors of the study include Christopher Thomas, Kechi Nzerem, and Joss Matthewman at Moody’s RMS, Christine Shephard and Laura Geselbracht from The Nature Conservancy.

More information: The spatially variable effects of mangroves on flood depths and losses from storm surges in Florida, Cell Reports Sustainability (2025). DOI: 10.1016/j.crsus.2025.100531. www.cell.com/cell-reports-sust … 2949-7906(25)00227-7