Report

Sustainable Asset Valuation of Coastal Wetland Restoration in Chile

Improving climate resilience through nature-based infrastructure in the Rocuant–Andalién wetland system

This report evaluates the economic, social, and environmental benefits of restoring parts of the Rocuant–Andalién coastal wetland system in Chile using the Sustainable Asset Valuation (SAVi) methodology. It quantifies the value of nature-based infrastructure (NBI) in reducing flood damage, enhancing climate resilience, supporting biodiversity, and delivering economic returns through avoided costs, carbon storage, recreation, and avitourism.

By Nathalia Niño, Marco Guzzetti on May 31, 2025

Key Findings

  • NBI in Rocuant–Andalién can avoid up to USD 58.7 million in flood damage over 26 years, and when combined with benefits from recreation, land valuation, jobs, and carbon storage, total returns outweigh the USD 140 million restoration costs across all modelled scenarios.

  • Nature-based restoration delivers strong economic returns. For every dollar invested, the project can generate up to USD 1.30 in benefits—including increased land value, enhanced carbon storage, and avoided damages—while supporting Chile's climate resilience goals.

  • Restored wetlands provide critical social and ecological co-benefits. The project enhances biodiversity, supports migratory bird pathways, and improves quality of life for local communities by creating green spaces, jobs, and new opportunities for recreation and avitourism.

Chile's Biobío region is home to ecologically important coastal wetlands that play a critical role in reducing flood risk, supporting biodiversity, and providing climate resilience to nearby communities. However, the Rocuant–Andalién wetland system has suffered significant degradation due to urban expansion, pollution, and unsustainable development. These changes have increased the region’s vulnerability to flooding, saline intrusion, and biodiversity loss, threatening both human and ecological well-being. 

The American Flyways Initiative and partners are supporting the restoration of 579 hectares of wetlands in Chile's Biobío region. The project integrates green and hybrid infrastructure solutions, such as re-naturalized riverbanks, wetland rehabilitation, rain gardens, and birdwatching infrastructure, to enhance ecosystem services and benefit over 31,000 local residents. 

This report applies the International Institute for Sustainable Development's SAVi methodology to assess the impacts of these interventions using an integrated cost-benefit analysis. Six scenarios were modelled to reflect different levels of wetland degradation, carbon storage potential, and land valuation assumptions. 

All NBI scenarios assessed were found to be economically viable, with benefit-cost ratios exceeding 1.0. The most favourable scenario showed a return of USD 1.30 for every dollar invested, and net benefits of USD 42.45 million. Key outcomes include

  • up to USD 58.74 million in avoided flood damage and rental income loss,
  • increased land and property values due to reduced flood risk,
  • USD 78.64 million in social value from improved access to nature and recreation,
  • carbon storage benefits ranging from USD 1.37 to 4.57 million depending on degradation levels, and
  • additional benefits from local job creation and increased avitourism. 

The results confirm that coastal wetland restoration is a cost-effective, high-impact strategy for advancing Chile’s climate resilience and development goals, especially under high-risk climate scenarios.

Participating experts