Countries Are Building Giant ‘Sand Motors’ to Protect Their Coasts From Erosion

This story actually appeared on Grist And is part of Meteorological Desk Sharing.

When governments merge. Battling the threat of coastal erosion themselves, their default response is simple enough: if sand is disappearing from the beach, they add more sand to replace it. This strategy, known as “beach nourishment”, has become the basis of coastal defenses around the world, complementing hard structures such as sea walls. For example, North Carolina has dumped more than 100 million tons of sand on its beaches over the past 30 years, costing more than $1 billion.

The problem of beach nourishment is obvious. If you dump sand on an eroding beach, it’s only a matter of time before that new sand runs out. Then you have to do it all over again.

Beach-nurture projects last about five years, but they often disappear faster than expected. Moreover, a large coastal storm can wipe them out overnight. And the costs are staggering: Dredging in new sand requires leasing and operating large diesel dredge boats. Only the wealthiest areas can afford to do this year after year.

Now, after decades of relying on repeated beach nourishment, a new strategy for managing erosion is emerging on coastlines around the world. It’s called the “sand motor” and it comes from the Netherlands, a low-lying nation with centuries of experience in coastal protection.

A “sand motor” isn’t a real motor—it’s a sculpted landscape that works with nature instead of against it. Instead of recreating the beach with a uniform line of new sand, engineers extend a section of beach at an angle into the ocean. This stretch of land stretches miles along the coastline, along with the rest of the natural coastline.

While sand motors require a much higher initial investment than typical beach nourishment—and many times more sand—they also protect more land and last longer. Developed countries such as the Netherlands and the United Kingdom are repeatedly turning to these megaprojects as alternatives to nutrition, and the World Bank is financing a sand motor as part of a billion-dollar adaptation program in West Africa. is aimed at combating sea level rise. . But these large projects work only in areas where erosion is not yet at a critical stage. That means they’re unlikely to show up in the United States, where many coastal areas are already on the verge of disappearing entirely.

The idea for this project came from a The Dutch professor’s name is Marcel Stew., who had watched with dismay as their country’s government spent billions to nurture the same coastal areas over and over again as sea levels continued to rise. Steve pitched the idea to the government, which hired a large dredging company called Boscales to build a prototype on the coast south of The Hague.

Even this experimental project, called the Dutch “Sand motor“It was an unprecedented move. Boscals scooped up about 28 million cubic yards of sand from the sea floor that the Netherlands uses in a given year on nutrition projects across the country. Engineers then sculpted the sand into a hook. are curved eastward along the coast.ensuring that the tides would push the sand to the northeast towards the beaches near The Hague. They also built a lake in the center of the sand structure so that the local people would not have to walk nearly a mile to reach the water. In the years since the Boscales finished construction on the $50 million project, the sand hook has flattened, almost as the tide reaches the beach.