How Giant Plant Pots Could Save Shorelines
WHY YOU SHOULD CARE
This design could solve two environmental problems.
By Carly Stern
Oyster bars are a classic happy hour favorite, but you probably haven’t heard of OysterCastles — blocks made of stackable eco-friendly material that serve as homes to oyster populations, which are dwindling. But these Lego-like mollusk dwellings also serve another purpose: They help to remediate shorelines and preserve salt marshes. A win for the earth, a win for the oysters.
Earlier this year, an exhibit at the Cooper Hewitt Museum featured designs for a creation that solves two somewhat similar environmental issues. The TetraPOT is an option that could keep shorelines in place, while also renewing a coastal shrub that’s become a victim of climate change.
The TetraPOT was on display earlier this year as part of the exhibit “Nature: Cooper Hewitt Design Triennial.” Designed by Taiwanese designer Sheng-Hung Lee and Malaysian designer Wan Kee Lee, this soil erosion defense method presents an alternative to the more familiar tetrapods: large, concrete blocks that are scattered along shorelines to help keep coastlines in place.
TetraPOTs, which look like giant plant pots, link the preservation of shorelines with the preservation of mangroves.
But the cheekily named TetraPOT simultaneously caters to another disappearing act: mangroves. More than 35 percent of global mangrove forests have been destroyed by climate change. Their steady disappearance creates a catch-22: The shrubs themselves help prevent soil erosion by acting as natural barriers. During storms, wind and wave swells lose energy and height as they pass through the small trees’ tangled roots.
TetraPOTs, which look like giant plant pots, link the preservation of shorelines with the preservation of mangroves. A three-part system with holes and a central chamber houses mangrove seedlings inside a decomposable pot with a concrete exterior. Roots grow out of the holes, creating an interlocking system that will remain long after the pod has deteriorated. As the shrub grows, the roots spread downward and attach to nearby seeded pods. These clutch the land to gradually form an interconnected system that protects the soil against storms over roughly 14 months.
The TetraPOT caught the eyes of Cooper Hewitt curators, who thought it was a fascinating redesign of an existing product –– one that can be reframed to accommodate natural growth, says Andrea Lipps, a co-curator of “Nature: Cooper Hewitt Design Triennial.” Regular tetrapods don’t enable much growth for natural sea organisms — except for oysters, which might grow on the solid concrete slabs. But the redesigned TetraPOT pushes people to consider how objects that already exist in their daily lives can be harnessed to create new benefits, says Lipps.
TetraPOTs could help restore habitat in highly degraded systems where biodiversity has been harmed, says Carter Smith, a researcher at the Duke Marine Lab studying coastal habitat restoration. And they could also serve homeowners in places like Florida who rely on salt marshes or natural mangroves to act as coastline’s natural barriers against erosion. Smith points out that rigidly drawn property lines aren’t compatible with the fluidity of shorelines to begin with. Storms naturally close old inlets and create new ones, but losing even a single foot of shoreline for a waterfront landowner means losing private property that could put their home at risk, she says.
While TetraPOTs are still in the design prototype phase, other similar products have hit the market. In addition to the OysterCastles, manmade ReefBalls establish new habitats for coral reefs. But Carter says she’s not yet seen a product as complex as the TetraPOT for mangrove habitats, that can foster growth of an organism within the structure itself.
To be sure, this design isn’t ready to hit real world markets yet — so any upside is speculative. It’s possible that mangroves won’t grow well when fully encased in concrete structures, or that this kind of manmade device could disrupt some biological interactions in the marine environment, Carter says. But even so, there’s value in any accessible way to get people interested in protecting coasts and restoring habitats. The path from design to field testing to the commercial market can feel glacially slow — but a changing climate could hurry it along.