The Dutch Built a Massive Wave Machine to Study Flooding
THE STORY GOES like this: A little Dutch boy spots a hole in a dike, and sticks his finger in to plug it up. He stays there for days and nights, ultimately saving his country from watery ruin. Apocryphal? Well, yeah. But the people of the Low Country have been preoccupied with keeping the ocean at bay for centuries, an interest that has only intensified with the threat of climate change. That means designing better infrastructure—which is why a Dutch company, Deltares, has built a machine that generates the world’s biggest artificial waves.
Their machine, the Delta Flume, works like this: Pistons rhythmically shove around more than two million gallons of water in a 900-foot-long concrete trough, like a giant toddler splashing back and forth in a bathtub. Eventually, the waves double back on themselves to form monsters up to 15 feet high.
The project isn’t about making really big waves for the sake of making really big waves, though, says Dan Cox, a coastal engineering professor at Oregon State University, which houses the largest research wave machine in North America. The purpose of wave machines is pretty simple: to see how human-made structures—breakwaters, seawalls, giant concrete blocks—stand up to crashing waves and giant storms before millions of people trust them to protect them from the elements. For wave machines, “bigger is better, because you don’t have to worry about scale effects,” Cox says. A giant machine sidesteps factors like surface tension and sand grain size that, at the wrong scale, could screw up results.