Rotterdam tested its storm surge barrier last Saturday, and a large audience came out to cheer what must be one of the most unusual civic ceremonies. The barrier system is checked annually in September.
Hundreds showed up for the test of the 420-metre-long movable barrier near the city. The barrier, considered one of the world’s engineering wonders, helps protect the region against flooding the area, where parts of the city and its suburbs are as much as six metres below sea level. In an emergency, when water levels have risen 3 metres, the barrier operates automatically.
The barrier’s two arms, each longer than the Eiffel Tower, took 30 minutes to close and a further 90 minutes to submerge completely. It has to sink slowly to avoid sending waves of water into the city. Once the barrier’s six engines are activated, they bring the barrier walls together. The hollow walls float on the river until they reach each other. Next, the valves are opened, the walls fill with water and the barrier sinks into place.
