Is China's coastal engineered defences valuable for storm protection?

Area of Science:

• Coastal engineering
• Environmental economics
• Storm risk management

Background:

• China has extensive experience with hard coastal defenses for storm protection.
• Historical storm impacts and economic damages provide data for analysis.
• Hard engineering plays a role in mitigating storm damage.

Purpose of the Study:

• To examine the economic effects of hard engineering in storm damage mitigation in China.
• To quantify the storm protection value of hard engineered defenses.
• To compare the cost-effectiveness of hard engineering versus ecosystem-based measures.

Main Methods:

• Analysis of historical storm impact data from 1989 to 2016.
• Statistical examination of the relationship between economic damages (TD/GDP) and coastal defense length.
• Economic valuation of storm protection services provided by hard defenses.
• Comparative cost-effectiveness analysis with coastal wetlands.

Main Results:

• A significant negative relationship was found between storm damages and the length of hard engineering.
• The average storm protection value of hard engineered defenses in China is estimated at CNY 3.18 million/km.
• Hard engineered defenses provide an average annual economic value of CNY 6.04 billion.
• Coastal wetlands are more cost-effective than hard engineered defenses.

Conclusions:

• Hard engineered defenses are critical for storm mitigation but less efficient than coastal wetlands.
• China should consider shifting focus towards ecosystem-based measures or combined approaches for future storm damage prevention.
• Integrating ecosystem-based solutions can enhance coastal resilience and cost-effectiveness.