Scientists at the University of Texas at Arlington are using Roman concrete and 3D printing coral reefs that provide marine habitats, store carbon, and protect coastlines from storm surges.
You might wonder — where do Roman concrete, algae, and 3D printers meet? At the University of Texas at Arlington. There, a small team of researchers is racing against the clock to save marine wildlife by building artificial coral reef structures from Roman concrete using 3D printing.
These man-made reefs aren’t alive, but they are designed to serve as new homes for algae, fish, and eventually coral larvae that have lost their natural habitat.
The need for innovation, like 3D printing coral reefs, is urgent. Nearly 40% of the world’s coral reefs have already been damaged by warming oceans, ocean acidification, and pollution. Corals are highly sensitive to rising sea temperatures, which cause bleaching — a stress reaction that leaves reefs vulnerable to disease and death. Combined with overfishing and coastal development, these pressures threaten to erase reefs entirely by the end of the century. Without intervention, the ecosystems that support a quarter of marine life could collapse.
That’s where the Texas research team steps in. With a $2 million grant from the National Science Foundation, civil engineering professor Warda Ashraf and her colleagues are 3D printing coral reefs made from a material that has already stood the test of time: Roman concrete. Unlike modern concrete, which erodes in seawater within decades, Roman concrete actually grows stronger when exposed to ocean water.
Earlier attempts at artificial reefs have used concrete blocks, old tires, or even sunken ships. Many broke down quickly, leached pollutants, or failed to attract enough marine life. The Roman concrete recipe offers a cleaner and more resilient solution. Its chemical reaction with volcanic ash creates new minerals that fill cracks and reinforce the structure — a perfect property for something meant to last under the sea.
In fact, small test structures placed in Baffin Bay, south of Corpus Christi, showed a 40–50% increase in strength after five months in seawater, while barnacles and algae began colonizing their surfaces almost immediately.
The project brings together experts across disciplines. Biologist Laura Mydlarz is studying how coral larvae and other organisms interact with the structures, ensuring that the artificial reefs support rather than harm marine ecosystems. Civil engineer Adnan Rajib is modeling how 3D printing coral reef placement can reduce coastal flooding and storm surge, adding another layer of protection for vulnerable communities. Together, the team is designing reef shapes that mimic natural coral structures, providing fish with vital shelter and breeding grounds.
The benefits go beyond habitat. The researchers are modifying the Roman concrete recipe to capture and store carbon, offering a dual climate solution: restoring marine ecosystems while locking away thousands of tons of CO₂. This approach could help offset the very emissions driving reef decline.
3D printing coral reefs also adds flexibility to the project. Scanning real coral reefs allows the team to replicate their intricate designs with precision. Different ocean regions may need different shapes, sizes, and placements, and printers can produce customized modules quickly. This adaptability means the technology could be deployed in diverse environments around the world.
See also: How New Coral Reef Restoration Technology is Giving Corals a Fighting Chance
For now, the research is being tested in the Gulf of Mexico, where reef systems have been heavily degraded by warming waters, hurricanes, and runoff from coastal development — making it an ideal proving ground for the new structures.
Of course, artificial reefs can’t fully replace natural ones. But they can buy time. By creating safe spaces for marine life, they help ecosystems recover while broader efforts, such as reducing carbon emissions and cleaning up coastal pollution, take hold. In a future where natural reefs may struggle to survive, these printed structures could play a crucial role in preserving marine biodiversity.
The project shows how ancient wisdom and modern technology can work together in unexpected ways. Roman concrete, perfected over 2,000 years ago, is now being used to solve one of today’s most urgent environmental challenges. And with coral reefs on the brink, that unlikely combination of old and new might just be what saves them.
