Securing the Asian Mega-Deltas from Sea-Level Rise, Flooding, Salinization and Water Insecurity


Home to 400 million people, the densely populated Asian mega-deltas are biodiverse, fertile, and productive food baskets dominated by rice, fisheries, and aquaculture that support millions beyond delta dwellers. Deltas are reaching a significant tipping point. More than 100 million small-scale producers living in Asian mega-deltas face risks to food and nutrition security and livelihoods from impacts of climate change.

Recent models of coastal elevation show that the Asian mega-deltas are much lower than previously assumed and will be severely affected by increased incidence and intensity of floods, sea-level rise, and salinization of soil and freshwater. The models also predict water shortage, severe cyclones, and climate extremes, which can lead to an annual loss of 6% of GDP in Southeast Asia, over twice the global average expected loss. Furthermore, freshwater withdrawals far exceeding sustainable capacity are contributing to land subsidence, and rapid biodiversity loss threatens protective mangrove forests. These trends will put increased pressure on those remaining, who are often aging women facing labor shortages, decreased productivity, and reduced livelihood opportunities.


This Initiative aims to support the creation of resilient, inclusive, and productive deltas, which maintain socio-ecological integrity, adapt to climatic and other stressors, and support human prosperity and wellbeing.

This will be achieved through:

  • Management of critical risks exacerbated by climate change specific to Asian mega-deltas such as flooding, salinity, water shortage and dependence on upstream activities for freshwater flows.
  • Support for enabling policies and regulatory systems.
  • Implementation of adaptation and diversification technologies and practices, and advancement of decision-support tools across food system value chains to address capacity inequalities and poor cross-sector coordination while enhancing community-based resilience choices.
  • Dissemination of research outputs for equitable and sustainable management of Asian mega-delta landscapes, supported by multi-stakeholder exchanges informing investments in resource-efficient and environmentally responsible practices.
  • Stimulation of investments in sustainable production systems by co-developing inclusive business plans with value chain actors.


Proposed 3-year outcomes include:

  1. At least five development and/or investment programs use adaptation matrices developed by the Initiative to decide which agronomic, aquacultural and livestock technologies and farming systems can be scaled, thus initiating the scaling process and targeting at least US$100 million in support for millions of producers.
  2. Public and private sector investor groups in five countries actively pilot with stakeholders priority investment opportunities, innovative financing solutions, advisory services, and insurance products. Such investments increase the willingness to adopt climate-, biodiversity- and environmentally-responsible value chain practices among 200,000 farmers and value chain actors.
  3. More multi-functional and climate-resilient deltas, supporting diverse and equitable food systems through better-aligned land and water policy and regulatory frameworks and investments, informed by appropriate adaptation technologies and practices, new scaling strategies and interventions, and institutions for managing stakeholder inequalities.
  4. Women, youth, and other marginalized groups are empowered to access delta resources and technologies and to be more equal partners in food systems innovation, taking part in shaping adaptation technologies and practices and new scaling strategies and interventions, while benefiting from more inclusive water and land policies and regulations.
  5. At least three policy interventions are formulated by government agencies in Asian mega-deltas and at least three development programs are designed based on increased understanding of drivers and trade-offs in change processes.



Climate adaptation measures against sea-level rise, floods, water shortage, soil, and freshwater salinization are developed. Smallholders and policymakers have access to timely, relevant information and financial solutions supporting adoption of improved coping strategies.


Diversification and intensification of food systems with micronutrient-rich fish and livestock, vegetables, and pulses, alongside staple foods, increase opportunities for diet diversity and quality available to communities.


Diversified farming and food systems have large potential to attract investment by managing risk, offering income stability, and reducing out-migration. Nature-based adaptation services can buffer the impacts of climate shocks for local communities as well as for poor consumers in urban areas.


Women, youth, and other marginalized groups are effectively engaged in designing and implementing adaptive land and water use and management solutions, and benefit from inclusive food systems through broader governance reform, improving their livelihoods and socio-economic empowerment.


The adoption of nature-based, resource-conserving, efficiency-enhancing food systems through digital solutions, index-based actions, and incentive mechanisms helps Asian mega-deltas reduce pressure on natural resources, accelerate ecosystem restoration, and curb habitat and biodiversity loss.


For more details, view the full preliminary outline


Header photo: A farmer tends to her maize crop, an example of recession agriculture on the floodplains of the Tonle Sap at Phat Sanday, Cambodia. Photo by N. Palmer/IWMI.