Can 3D printed reefs save fish, oceans and beaches?
A small Dutch crowdfunding project is trying to 3D print reefs to provide habitat for fish, protection for beaches and coastal communities threatened by rising seas, and a future for reefs devastated by bleaching and other damage.
If your first thought is: there’s no way 3D printing, which works best on a small scale, could replace thousands of cubic miles of dead reef all over the planet, you’re not mistaken.
“I don’t believe we can rebuild all the coral reefs in the world. I think…the scale is way too big,” project co-founder and marine biologist Astrid Kramer told me recently. Tech First Podcast.
“But what we can do in some places is two things: it saves time by placing these structures, we can protect fragile low-lying areas that are suffering from erosion or flooding because the reefs are dying. And we are placing substrate for research purposes, because many scientists are working extremely hard to find these species that can withstand higher temperatures, and they will become new reefs that can adapt to climate change.
Coral reefs are in massive decline around the world, and some scientists estimate that we could lose 70-90% of our reefs due to warming ocean waters.
This has all sorts of negative consequences: a quarter of the world’s fish live in and around reefs, reefs are critically important protectors of beach communities threatened by high waves and tides, and they support a huge amount of biodiversity.
This led Kramer and his co-founder Nadia Fani, a computer scientist who led the construction of the first large-format concrete printer, to begin Construction.
Of course, no one prints the corals themselves. Corals are tiny sea creatures that build exoskeletons of calcium carbonate. Collect billions of them over decades and giant reefs are formed.
But corals need an anchor: a place to attach themselves. Floating in sandy-bottomed waters, they will never be able to settle down and begin to build. Give them something to hold on to, and they just might start a colony.
Even small beginnings have a big impact, says Fani.
“So even if you start small…one square kilometer already, it could have a big impact,” says Fani. It could really protect a coast, a beach, a resort, like an area where a community lives and needs protection because the sea is rising.
The first steps are to be able to print a reef substrate that is about one cubic meter in size (think a sugar cube that is about three feet by three feet by three feet). It is important to be able to 3D print, because you match individual sites. Every place is different, says Kramer, with different hydrodynamics, different fish, different algae and different coral species.
“It’s like everyone has a different house,” says Kramer. “You can consider the habitat needs of not only the coral, but also the herbivorous fish that live nearby and keep the corals clean. You can consider perhaps the function of breaking waves, providing habitat for octopuses or sea urchins, also very interesting species when looking at reef ecology.
Their current technology can print complex shapes by delivering a binding agent, which can simply be water, onto a powder mixture. After finishing a layer, the machine lays down more powder, binds it again and starts again. The result can be an amazingly natural-looking man-made rock with plenty of nooks, crannies, and crevices for corals and other reef flora and fauna to attach themselves to, make homes, hide from predators, and begin building.
Another thing that is unique: the local community.
Coastruction’s founders don’t think they can scale to global demand, so their goal is to provide the tools – like the 3D printer – to local people and design the technology to use cheap, locally available materials, including cement, sand and various binders to create the artificial coral reef substrate. No high temperatures or chemical additives are required, and any powder or sand material not used in one print will be used in the next. The 3D printer works on site, so there is no transportation of finished blocks required.
Currently, the team works with communities in Hawaii, Fiji and the Seychelles, as well as with local authorities in the Netherlands. Nature Seychelles, an environmental organization in the western Indian Ocean, is testing some of their samples.
It’s not just the Netherlands, with huge tracts of land dredged from the ocean and protected by dykes or tropical islands that can benefit.
Fani currently lives in Florida, and her home is literally four meters (about 12 feet) below sea level. Large parts of the United States and other wealthy countries also lie below sea level, and if reefs are eroding because corals are dying, the increased wave action is likely to increase flooding and storm damage. She grew up in Italy, which is fighting to keep Venice from sinking into the Adriatic Sea.
The ultimate goal?
Restoration of damaged reefs, protection of communities and habitat of ocean species at risk.