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Sustainable Deltas Initiative Shares Tools to Mitigate Submerging Coastlines

October 16, 2014

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October 16, 2014 – The Netherlands, no stranger to coastal flooding, was the launch location for an international program focused on protecting vulnerable deltas worldwide. Announced in September in Rotterdam, the initiative intends to spawn new research and develop new tools aimed at responding to the threats to vulnerable delta and riverine coastal areas in the 21st century.

Deltas are important to humanity. They cover one percent of the Earth’s surface but provide homes for a half billion on the planet. Major cities, harbors, farms and even forests occupy deltas. Climatologists are projecting that in the 21st century 50% of the world’s deltas will be at risk from four phenomena: changes in river flow from weather extremes causing extensive erosion, subsidence of delta land areas, saltwater intrusion into coastal aquifers from declining freshwater volumes, and rising sea levels to the point that natural habitats and human land use and settlement is being severely disrupted.

The initiative, entitled Sustainable Deltas 2015, includes 21 universities and institutes from 13 different countries including many of the most vulnerable. Three delta demonstration sites will serve as modeling frameworks for the research and testing of technologies to address sustainability. These include the Ganges-Brahmaputra-Meghna (seen below in this Envisat image), the Mekong and Amazon River deltas. The next three years will be devoted to developing a science-based modeling tool to help define policy at the regional and local level.

Through this tool governments will learn about how to mitigate the risk from rising sea levels and storm surges. They will look at natural remedies such as planting of mangrove forests, and building of berms and natural polders to fight coastal erosion. They will be able to index and predict delta vulnerability and develop population policies that include migration and adaptation.

When the Dutch were faced with the major flooding in 1953 their answer was to build artificial polders and berms to hold back the water of the North Sea. This type of approach would be prohibitively expensive should all world deltas adopt it. Instead a new approach is needed that incorporates “soft” solutions using nature to assist in holding back rising seas and mitigating storm surges. This has led to restoration of wetlands and building of mangrove forests at the mouths of the world’s major rivers. But that can only work for so long when sea levels continue to rise. So coastal nations will need to consider far more activist interventions as they experience the consequences of climate change.

To learn more about the impact of climate change on rivers across the planet in the search box on the 21st Century Tech home page type “rivers climate change.”