ADB Report Warns of Surging Coastal Flood Damage in Asia-Pacific

Asia and the Pacific's coastlines generate $7 trillion in annual economic output but face severe risks from rising sea levels and worsening natural hazards without adequate adaptation, according to a report released on 21 October 2026 by the Asian Development Bank (ADB) in Manila.

The publication, titled Asia–Pacific Climate Report 2026: Coastal Risks on the Rise—Actions for a Resilient Future, states that annual coastal flood damages across 30 regional economies could rise from roughly $27 billion today to between $172 billion and $199 billion by 2050, and up to $739 billion by 2100 if adaptation measures are not implemented.

According to the ADB, investing between $9 billion and $19 billion annually in coastal protection could keep flood damages near current levels, potentially avoiding between $178 billion and $360 billion in damages each year. The bank noted that resilience investments could yield benefits up to 20 times greater than the required costs.

More than 400 million people across the region live within 10 kilometers of the sea. The report notes that while larger economies face high absolute economic losses, small atoll nations could experience annual flood damage equal to 30% to 60% of gross domestic product by 2100 under a high-emissions scenario.

Additionally, the report projects that major coastal cities, including Bangkok, Jakarta, Kolkata, and Mumbai, could experience 100-year flood events annually by the end of the century. Disruptions to regional ports threaten between $40 billion and $45 billion each year.

To address these risks, the ADB recommends governments incorporate adaptive planning into development, strengthen governance, mobilize financing, and maintain long-term implementation. Although international adaptation finance to coastal economies in the region reached an average of $11.4 billion annually in 2022–2023—up from about $5 billion in 2015—the ADB highlighted that a significant financing gap remains, requiring broader mobilization of public, private, and concessional funding.

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