Coastal erosion and flooding pose growing risks to the DEEP C Industrial Zone in Hai Phong, Vietnam. This assessment evaluates how planting coastal mangroves can reduce flood damage, control erosion, and generate long-term economic and environmental value.
In Hai Phong, Vietnam, rising sea levels, storm surges, and coastal erosion are putting low-lying industrial zones like DEEP C at risk. While a national sea dike is under construction to protect this economic hub, additional measures are needed to safeguard infrastructure, businesses, and communities from worsening climate impacts.
To complement the sea dike, DEEP C plans to implement a planted coastal belt of mangroves along the Nam Dinh Vu Sea dike. This nature-based infrastructure (NBI) solution is designed to reduce erosion, extend the dike’s lifespan, and provide important co-benefits, including carbon sequestration, biodiversity preservation, and support for fisheries. The proposed pilot will cover 70 hectares, helping to protect 646 hectares of vulnerable industrial land and benefit more than 12,000 workers, local residents, and nearby families in the DEEP C 2 industrial area.
To assess the value of this investment, the Nature-Based Infrastructure Global Resource Centre applied the Sustainable Asset Valuation (SAVi) methodology. Two implementation scenarios were analyzed: one using soil transfer to enable immediate planting, and another relying on natural soil accumulation over time.
The valuation quantifies how mangrove planting can reduce flood damage, curb erosion, support tourism and fisheries, raise property values, and reduce dike maintenance costs. In the most favourable scenario, every VND 1 invested generates up to VND 3.42 in benefits. Over 26 years, the intervention could avoid up to VND 129.8 billion (USD 5 million) in flood damage and generate substantial co-benefits.
Key results:
Up to VND 129.8 billion (USD 5 million) in avoided flood damage
Benefit–cost ratio of up to 3.42
Increased land and property values (up to VND 184.8 billion)
Lower dike maintenance costs and carbon storage benefits (up to VND 17.6 billion)
Additional benefits from job creation, fisheries, tourism, and public revenues
The results will support DEEP C’s investment decisions and provide a basis for scaling nature-based infrastructure in Hai Phong. They also offer guidance for local authorities, national planners, and development partners like UNIDO working to advance sustainable industrial development and climate adaptation in coastal zones.
The NBI Global Resource Centre aims to bring together key partners to establish a business case for Nature-Based Infrastructure (NBI).
Get in touch to learn more, collaborate, or for media enquiries and speaking engagements.
