Replacing hostile breakwaters – Reefy wants to preserve sections threatened by storm surges
With giant concrete blocks resembling Lego bricks that have a textured surface and tubular passages for water, the company Reefy (https://reefy.nl/) aims to protect coastlines threatened by storm surges. At the same time, they ensure that marine life settles, which additionally contributes to coastal protection.
Test off Rotterdam harbour
Decades ago, the Netherlands began to protect their coasts from erosion with so-called tetrapods. These are four-legged components made of concrete, each weighing six tonnes. They break waves, but also destroy marine life. Even worse are breakwaters made of discarded car tyres, on which no animals can settle. Moreover, toxic substances are released when the waves break them up. The oversized Lego blocks do not have all these disadvantages, they say.
The blocks are currently being tested off the Rotterdam harbour, the largest in Europe. Another test is to take place in Mexico. There are also plans to protect offshore wind turbines with these artificial reefs. “The idea for developing these blocks was to create a basis for colonisation with mussels, for example,” says Jaime Ascencio, CEO and co-founder of Reefy. “The idea is to create a living layer that can grow and heal itself as sea levels rise.” This will also be helped by a coating that offers nutrients to mussels, making them even more inclined to settle on the concrete.
Firmly connected to each other
The blocks are joined together so that waves cannot move them. The textured surfaces are designed so that marine life feels invited to colonise them. Other animals find shelter in the tubes through which water flows, for example from predators. Overall, natural marine life is restored, the developers hope. They can also be used to replace destroyed coral reefs. Coral reefs can reduce wave energy by 97 per cent and thus help protect coastal communities from storm surges and prevent erosion on beaches. Reefy blocks are designed to do this job when natural reefs are damaged.
