Wageningen World magazine contains an article about an impressive project called “Building with nature”, where nature helps us maintain the upper hand over the advancing waves and rising sea levels.
Oyster reef in Bangladesh
An artificial oyster reef was installed off the Bangladesh coast. The reef does not only break the rough waves from the sea, it also helps to combat coastal erosion. Mangroves swamps are replanted along the coast to further improve the coastal defences and also contribute to the development of nature and the economy, because they are the nurseries for tropical marine fish.
Oysters as coastal protection
The artificial oyster reefs in the Oosterschelde estuary reduce the influx of sand from shelves and mud flats. Migrating birds use the waters of Zeeland again as foraging grounds. Small oysters clamp onto the reef made up of old shells. They are quick to adapt their shape to their conditions and grow with the rising sea levels caused by climate change. Eventually a living reef of oysters is made.
Wave-breaking willow dyke
In the Noordwaard polder at Werkendam willows were planted to break the waves. By doing it this way, there was no need to raise the dyke and the resident’s view stayed as it is. As all stakeholders were involved in the planning from the early stages the decision-making process was straight-forward and quick.
Salt water-impeding Balance Island
By creating a Balance Island on the seaward side of the Haringvliet dam, a more gradual transition between salt and fresh water is allowed to take place. The island also reduces the impact of the salinization.
All around the world building with nature
Safety is especially at stake in vulnerable, heavily populated deltas. Hurricane Katrina showed less damage in areas where the salt marshes were intact. Building with nature can also contribute towards market-oriented development aid. The oyster reef in Bangladesh shows it is possible to have coastal protection that is cost-efficient and nature-friendly.