Dykes, sea-walls, groins and reservoirs have protected many people around the world from disasters. For a long time, these so-called “grey infrastructure” solutions were regarded as the default solution to protecting communities from weather-related events. It is time to rethink this.
Grey infrastructure solutions neither address any underlying causes of disasters nor do they prevent new risks from emerging. Green solutions, also called ecosystem-based solutions or green infrastructure, can offer new opportunities, either by working as stand-alone solutions or by functioning as a hybrid when grey and green infrastructures are combined.
Green solutions can not only reduce the hazard from which they are meant to protect communities, but they can also help to reduce social vulnerabilities, for example by providing food and water supply. For example, restored and maintained wetlands, such as floodplains, marshes, peatlands and lakes help to increase rain infiltration. They can act as a sponge to soak up excess amounts of river water, thereby reducing the flood risk, while also becoming a reservoir for water resources. This will also result in a flourishing biodiversity; for example, a restored wetland will become a source of food as fish like to use wetlands as breeding grounds.
But green infrastructure does not only offer additional benefits, it can also reduce the severity of a hazard event and minimize its impacts. When ecosystems are protected or restored along the coastlines or riverbanks, they can act as a natural buffer to hazard events and, as such, reduce exposure to these events.
Coral and oyster reefs, seagrasses, sand beaches, dunes, and barrier islands, mangroves, salt marshes and other wetlands have shown to contribute to shoreline stabilization, erosion control and/or wave energy attenuation. Green solutions can also protect grey infrastructure, thus reducing maintenance costs, supporting its lifespan and enhancing the sustainability of grey infrastructure.
On the occasion of the International Day for Disaster Risk Reduction, we are calling for decision-makers to factor green solutions into all aspects of disaster risk reduction (DRR) efforts. Despite their values, the degradation of wetlands and other ecosystems continues unabated, rendering local communities and the economy highly vulnerable to climate change.
Planning for protected areas and maintaining intact ecosystems while at the same time restoring ecosystems which have already been damaged is key to achieving the international societal and environmental goals, such as those embodied in the Aichi Biodiversity Targets and the 2030 Agenda for Sustainable Development, the Paris Agreement and the Sendai Framework for Disaster Risk Reduction.