Combining Concrete and Coral: Hybrid Reefs Offer New Solution to Coastal Flooding
Coastal flooding is a growing concern worldwide, as climate change leads to rising sea levels and more severe storms. But researchers at the University of Miami (UM) are working on a new tool to fight back against these threats: hybrid reefs that combine concrete and coral to weaken the force of ocean waves.
Most of the world’s coral reefs are dying off due to climate change. This not only threatens coastal communities, where reefs offer protection from flooding and erosion by breaking down waves, but also puts the military at risk. The U.S. Department of Defense recognizes this, which is why it’s funding the UM research in the hopes that hybrid-reef technology could someday protect bases like Navy Air Station Key West.
UM researchers received an initial $7.5 million grant from the U.S. Defense Department’s research arm last June to work on the project, called Reefense. It’ll be completed in three phases over five years. Teams from Rutgers University and the University of Hawaii also received funding to participate in other parts of the Reefense project.
The hybrid reefs will be built on a base of hollow, stackable concrete blocks that are full of holes to maximize the wave energy they can absorb. Researchers will then place a combination of lab-grown and nursery-raised coral on top of the concrete structure. The research teams also plan to biologically engineer more heat-resistant coral, including through selective breeding.
UM researchers plan to install and test two 20-foot-long hybrid reefs off Miami Beach near 80th Street later this month. In May 2024, the Reefense team will install a 160-foot hybrid reef off the coast of the Key West Navy base.
The potential of this technology is huge, as it could be used in coastal areas across Florida and beyond. Marine biology and ecology Professor Andrew Baker, who is a principal investigator for the project, says “If you’re not gonna try it here, where would you try it?” This innovative technology offers a ray of hope for our coastal communities and military bases, as well as the coral reefs themselves.
