Photo: Cyril Liebrand/Eureco.
Strong dikes
With a third of the land below sea level, flood protection is the highest national priority in the Netherlands. Over the next thirty years, 1,300 km of dikes will be reinforced within the Flood Protection Programme. A traditional reinforcement usually means constructing higher and wider dikes. This is a extensive, time-consuming and costly undertaking. In addition, the dike reinforcement often leads to resistance from the surrounding area because of the impact on the living environment and the classical landscape. There is a need for knowledge about effective and safe, but less drastic reinforcement measures and a sustainable dikemanagement.
Biodiversity
The Future Dikes project investigates how we can strengthen Dutch dikes with a species-rich grass cover. Previous research has shown that a biodiverse vegetation is highly resistant to the erosive effect of water overflow. The variation of grasses and forbs results in a diverse and deep root mat that holds the soil layers together. Both above and below ground, a species-rich vegetation therefore offers an excellent first layer of protection.
In addition, species-rich grass cover can contribute to the restoration of biodiversity, offering opportunities for a variety of plant and insect species. Moreover, dikes meander through the Dutch landscape and form a corridor between different ecosystems. A species-rich dike cover is in line with the Green Deal Infranatuur that various water boards have signed to guarantee the biodiversity and environmentally friendly management of the dikes. Research is needed to enable a large-scale application of species-rich grass cover in the Netherlands. More knowledge is needed about erosion resistance, the design, quality assessment and management of species-rich dikes.
