Protection system

Coral reefs inspire Hawaii’s coastal protection system

image from video courtesy of University of Hawaii

(BIVN) – The University of Hawaii plans to develop a “rapid resilient reef for coastal defense” – or R3D – to help protect coastlines from flooding, erosion and storm damage.

The university says the Living Coastal Protection System is inspired by coral reefs.

From the University of Hawaii press release:

The University of Hawaii will receive up to $25 million from the Defense Advanced Research Projects Agency (DARPA) to develop a coral reef ecosystem designed to help protect coastlines from flooding, erosion and damage from the storms. The goal of this five-year project, inspired by natural reefs, is to create an artificial structure that dissipates wave energy while providing habitat for corals and other reef life.

The groundbreaking project is a joint effort between the School of Ocean and Earth Science and Technology (SOEST) at UH Mānoa and the Applied Research Laboratory (ARL) at UH.

“The Rapid Resilient Reefs for Coastal Defense (R3D) project will be the first of its kind in taking an integrated ecosystem-level approach to designing and building a living system of coastal protection,” said Ben Jones, R3D Principal Investigator and Director of Ocean Science and Technology at the ARL. “It’s a huge challenge. We have assembled a team of experts right here in Hawaii who, in partnership with Florida Atlantic University and the Scripps Institution of Oceanography, will design real solutions that will help our community and other communities around the tropical Pacific that are already facing the effects of climate change. .”

image by Ben Jones from video courtesy of the University of Hawaii

Rising sea levels and wave-induced flooding during increasingly frequent storms threaten coastal sustainability and more than 1,700 military installations operated by the U.S. Department of Defense in coastal areas around the world . Natural coral reefs provide substantial protection to shorelines, absorbing and dissipating the intense energy of storms and waves. As sea levels rise and coral reefs degrade, existing storm mitigation solutions may prove insufficient and damage from storm surges and flooding will continue to impact communities. and infrastructure.

“This award will enable our world-class experts to develop cutting-edge technology that will have a significant impact here in Hawaiʻi and around the world,” said Michael Bruno, UH Mānoa Provost. “We are proud to have UH research at the forefront of creating a solution to a global problem.”

Combining engineering, ecology and biology

The new project integrates coastal engineering and hydrodynamics with expertise in coral reef ecology and adaptive biology to enable the team to rapidly develop a living breakwater system that can adapt to the rise seas and rising ocean temperatures.

“The typical fringing reef consists of a fore reef along the slope, a reef crest which absorbs much of the wave energy, and a protected back reef which is home to more delicate species”, said Zhenhua Huang, SOEST professor of ocean and resource engineering and principal investigator. for basic structure engineering. “We intend to achieve similar wave attenuation using thin-walled perforated core structures that are efficient and inexpensive energy sinks. We hope this project can provide a win-win solution for the preservation of coastal marine natural resources and coastal protection.

Reefense chart via University of Hawaii

Healing corals over time

The establishment of corals and other reef supporting organisms on reef structures is essential to ensure that the structures have the ability to grow and heal over time. Fragments of known heat-tolerant colonies will be attached to succession modules, reef-mimicking structures that will be attached to base wave-attenuating structures. Larvae of known thermotolerant coral species will also be encouraged to settle on these structures.

“Designing succession modules that attract coral larvae and then prevent them from being eaten or overrun by algae is essential to reviving a living reef,” said Josh Madin, associate research professor at the Institute of Biology. Hawaiian Marine (HIMB) in SOEST and Principal Investigator for Ecosystem Engineering. “The larvae are very poor swimmers and therefore need to be caught in cracks and nooks in the structure. We will use 3D design and biofilm chemistry to attract larvae and encourage colonization, while discouraging algae growth. In addition to this, we will use sounds that mimic a healthy reef to attract organisms that help coral growth.

Additionally, the team will explore cost-effective ways to supplement bleached coral feeding and even actively shade or cool the reef in the early stages of reef development and during marine heat waves.

“The planet’s coral reefs are declining under the combined onslaught of human impacts,” said Rob Toonen, HIMB professor and principal investigator for adaptive biology. “This project builds on more than a decade of research at HIMB into practical solutions for breeding thermally tolerant corals that can withstand these stresses and rebuild the reef structure that protects our coastal roads, runways and our neighborhoods.

The project is already garnering local support as an alternative to man-made coastal protection systems.

Rocky Kaluhiwa, President of the Koʻolaupoko Hawaiian Civic Club, said, “The Koʻolaupoko Hawaiian Civic Club strongly supports an approach like this, as it respects our traditional ways of managing our ʻaina and kai, balancing the seas and Earth.

The team will collaborate with scientists and engineers from Makai Ocean Engineering in Oʻahu, Florida Atlantic University, the Scripps Institution of Oceanography at the University of California, San Diego and Ohio State University. Additional partnerships will also facilitate various aspects of this project. To scale up this groundbreaking effort, Makai Ocean Engineering, a Hawaii-based company, will handle major construction, anchoring and installation; and an Australian company, Reef Design Labs, will create flexible, reusable forms to build hundreds of estate modules.