LOLA Landscape Architects: The Netherlands has got tens of thousands of kilometres of dikes, all told more than ten times the circumference of the country. For the Dutch, the presence of dikes is so obvious that they sometimes forget their presence at all, that a large part of their country lies below sea level, and that many rivers are higher than the surrounding area. Few people take into account the risk of a dike breach or flooding. Yet that is anything but obvious: the Netherlands has endured countless floods, houses have been washed away, and people have died. Dutch Dikes marks the first time in history that all of the Dutch dikes have been described in one document and database, at a pivotal moment in the age of Climate Change.
A dike is an elevated, originally (water) retaining ground body, with all its associated buildings and artificial structures. This definition includes all the dikes that have, or do not have, a flood defence function, plus an exceptional category that includes for example the defence line dikes: these dikes serve to hold back the water, but usually with the intention of stopping the enemy. A dike is therefore much more than just a kind of water defence; it is part of our culture. The Dutch are consciously and unconsciously bound to the dikes. The dike is also our hiking path, it is our museum, and it is our park. As the saying goes, it is better to live with the water than to only defend against it. The Netherlands is shot through with dikes, as is Dutch history and the life of the Dutch people.
For more than 2,000 years, dikes have kept the Netherlands safe and dry (with the occasional flood). What once began with the raise of small mounds of earth is now an extensive network of over 22,500 km of dikes and dams. Without those at least one third of the Netherlands would not be land but sea. Despite the many floods throughout Dutch history, and the presence of thousands of kilometres of dikes in the landscape, there has not yet been any detailed description of the location of all the dikes on the scale of the Netherlands, and there has been no comprehensive overview of the different types of dikes. This gap has now been filled. For the first time the dikes are fully mapped, the defense system is explained and the diversity is categorized. The result of Dutch Dikes is a geographic database containing all the dikes of the Netherlands: flood defences and non-flood defence dikes. The database was used to develop the map of dikes of the Netherlands, which displays the entire system of dikes. A second result is an overview of all different types of dikes, the dike typology. A dike is not just a dike: there are at least 43 substantially different kinds of dikes, all with different structures, histories, or regional locations. Some of these dikes operate in concert, in the nine so-called dike systems. All dikes are brought together in a unique, systematic genealogy. Dutch Dikes presents an overview of our dikes in their current state, and offers a look towards the future.
Presently about 40% of the world’s population live in coastal areas in a complex and dangerous cocktail of rapid population growth, haphazard urban planning and quite often a neglected flood protection system. Subsidence and a changing climate will increase to influence the livability in delta’s worldwide.
The lowlands of the Netherlands provide living proof that dikes can be used successfully to keep a densely-populated delta dry. The Dutch are kept safe by a comprehensive system of design, management and inspection of these water works. Innovations in dike building have been arrived at by trial and error: brilliant inventions and intelligent dike management proposals have frequently followed in the wake of a disaster or a fiasco. So what will the future hold? The Dutch government and the water sector take a very long view, and look well beyond the country’s borders. The Netherlands is only one of many densely-populated delta regions, and recent events bring home to us that floods and devastation are by no means confined to developing countries. Since Hurricane Katrina laid waste to New Orleans, Hurricane Sandy has left a trail of disaster in New York, major floods have afflicted Somerset (UK), and there is a recurrent risk of flooding in the rivers throughout Central Europe. It is indeed the failure of flood protection in a number of delta metropolises in the developed world that drives innovation in dike building in the Netherlands today.
The launch of a new Delta Plan for flood protection in the Netherlands cannot be divorced from the growing number of freak weather conditions worldwide. Hurricanes cause devastation, but much of the damage arises in the hours and days that follow, with the failure of flood defences. In the wake of Hurricane Katrina, Lake Pontchartrain flooded the low-lying districts of New Orleans, because the structure and foundations of the floodwalls that were in place there proved to be inadequate. New Orleans and New York have now adopted the ‘Dutch approach’ as their new blueprint, and many Dutch civil engineering firms are actively exporting their expertise, services and products within the project that has been named ‘Topsector Water’. What is this expertise that is exported from the Netherlands to the other countries with delta regions? And what is the vision underlying the Dutch approach to the future of the dikes in the Netherlands itself? This is of interest to all those who work to keep deltas dry worldwide.
Eric-Jan Pleijster, Cees van der Veeken 2015
Landscape Architecture: LOLA Landscape Architects
Type of project: Research/publication
Publication: December 2014 (first edition), February 2015 (second edition)
Location: The Netherlands
Publisher: NAI010 Uitgevers
Graphic design: Koehorst in ‘t Veld
Partners: Ministery of Infrastructure and the Environment, Deltares, Dienst Landelijk Gebied (DLG), Hoogheemraadschap Holland Noorderkwartier, Hoogheemraadschap Rijnland, Hoogwaterbeschermingsprogramma, Rijksdienst voor het Culturele Erfgoed.
Image Credits: © LOLA Landscape Architects