Dutch at Werk: Designing with Water
The Dutch have an elevated sense for planning and adapting to the will of the sea. With one third of The Netherlands located below sea level, the Dutch have been planning around water since the first dikes and dams were built in the 13th century. In 1953 a storm caused the North Sea to flood 640 square miles of land, causing 1,835 casualties. After this event the municipal plan to deal with threats from flooding, called the Delta Works, was created. The plan centered around an extensive network of engineered protections to flooding including dikes, levees, and dunes, culminating in the construction of the Maeslant Storm Surge Barrier in Rotterdam.
From afar the Maeslant Barrier appears subtle on the horizon. A maze of twisting small routes and roundabouts leads you out of the tulip fields and past dozens of hydroponic farms and greenhouses to an active working waterfront. The plan for the Maeslant Barrier was tricky. The port of Rotterdam is the most heavily trafficked port in Europe and one of the busiest ports in the world. The storm surge barrier that was to protect the port and the surrounding area needed to be located in the channel connecting Rotterdam to the North Sea but not permanently close it off to shipping traffic, like other large surge protection projects like the Thames Barrier. As a solution, the structure was conceived as a pair of movable gates, pivoting on massive 10 meter ball joints (the largest in the world). The joints are connected to 210 meter long gates which are attached to 237 meter long arms. Standing up, each arm would be taller than the Eiffel Tower.
Scale of the Maeslant Barrier
Arriving at the coast, the barrier is not in sight but obstructed by a large hill. The peculiarity in the landscape turns out to be a mound created as a viewpoint for visitors to take in, yet conceal, the vastness of the Maeslant Barrier. When out of operation the barrier sits on pedestals within a dry dock. The trusses that form the arms are mostly hollow which allows the structure to move easily in to place once the dry dock is flooded. Once in the waterway, the hollow trusses are flooded and sunk, effectively blocking any incoming storm surge. However, space is left in between the gates to ensure they don’t crash into one another during choppy waters. Space is also left for a small amount of water to flow beneath the gates, preventing damage to the ecosystem and to protect the barrier from becoming a wedge in the muck at the river bottom. In the fall, when the barriers operations are routinely tested, crowds gather in the thousands on the hill to watch the marvel in operation.
Maeslant Barrier Dry Dock
The function of the barrier is piloted by an algorithm that measures the potential for storm surge based on current sea level and barometric readings/ weather events. The closing mechanism is run entirely by computer (though monitored) and will close automatically under conditions of 2.9 meter sea level rise. The entire system is triggered and operated by computers on site (with a manual override possible if needed), which dictate when the arms should be moved, flooded, and then have water pumped out to float back into place within the dry docks. There is a backup grid in case the main grid fails and a diesel generator for last resort.
The scale and complexity of the Maeslant Barrier didn’t come into focus until my trip was accentuated by an impromptu personal tour. Jeroen, a project engineer and my tour guide, had great pride and trust in the barrier’s function; he lives with his family just passed the barrier on the water’s edge. As Jeroen shared the Dutch perspective on the barrier and on climate change in general, he also allowed me to view the barrier from a closer perspective. Sightseeing is relegated to the hilltop, still a good distance away. With Jeroen, I was able to walk under the barrier and looking down from the famed ball joint to the end gate of the arm.
Benthemplein Water Square
The Maeslant Barrier represents one scale of the many instances of woven resilience that can be found in Rotterdam. This engineering marvel is certainly not the only way the Dutch deal with resilience to sea level rise and storm surge. A more integrated project that has become commonplace across Rotterdam are water plazas (or water squares), public parks with recessed areas built for storm water retention. A dynamic space, the Benthemplein water square was designed to make its function explicit; during peak rain events water can be seen pouring down the “water wall” and cascading through a series of rube-goldberg like gutters that outline the space and carry water to the three basins for storage. When in a dry state the park has ample space for the students of the adjacent college to utilize in addition to a basketball court that is housed in the deepest basin and with oversized gutters designed for use by skateboarders.
Benthemplein Water Square
It became clear when talking to Jeroen that the Dutch understand the importance of their relationship with the waterfront. In grade school, children learn about the great flood and what the country has done to prevent another one. There is a keen understanding even among children of the need to plan and work with the water at the country’s edge. Jeroen was also perplexed by the US, and New York in particular, for its perceived lack of urgency in adapting to the realities of our waterfront post Hurricane Sandy. No doubt high tax rates help fund these public infrastructure projects but there is also very clearly a public awareness initiative that is severely lacking in the states.
A reminder of the danger in coastal community