Natural disasters caused by warming temperatures are typically associated with catastrophic consequences, but what if there was a way to harness the strong ocean currents they generate in a productive way? That's the question that lies at the heart of MIT Self-Assembly Lab's latest project, which explores how these forces could be used to develop sandbars that could eventually develop into islands and help protect vulnerable coastal communities.
Presenting their research at the TED conference in Vancouver a few weeks ago, Skylar Tibbits recounted how the idea has been developing for him over several years, since one of his thesis students suggested that mudslides and landslides could be used to build parks. "It has always been on my mind that maybe we could take these natural disasters—earthquakes, tsunamis, windstorms, mudslides, landslides, fires—and build instead of destroy," he said.
The team partnered with Invena, an organization in the Maldives focused on tech-forward solutions for conserving the islands, to develop a system of underwater structures that use wave energy to create sand accumulation in strategic locations.
First, a series of "low-cost, easy to deploy, and adaptable" underwater ramps are installed. As waves pass over the ramp, the force carries sand particles and allows them to accumulate in front of the ramp, eventually forming a sand bar above the water's surface. "Over time, the goal is that the accumulation of sand will grow into new islands or help rebuild existing beaches, creating an adaptable solution to protect coastal communities from rising sea levels," their project description states.
While Tibbits recognizes this will be a "very long-term project," he believes this could be a far better alternative to dredging or building barriers—which are "static" solutions for a dynamic problem. Having observed natural sandbars reaching over six feet in height form in just a few months, he knows this process could yield real results.
The team installed a 9.8 x 9.8-foot structure in the Maldives this February and are currently monitoring it and collecting data to analyze the sand accumulation with the goal of installing a second experimental structure by year's end. "This is the first phase of a multi-year project with various field experiments and years of data collection all with the aim to create a system of submersible structures that can adapt to the dynamic weather and wave conditions and naturally grow our coastlines," the team notes. "We envision far-reaching applications for rebuilding and stabilizing heavily-populated coastlines and vulnerable island nations with our approach."