Coastal challengesMitigating Coastal Flooding, Erosion and Storm Damage

Published 28 December 2020

Sea level rise and wave-induced flooding during increasingly frequent storm events threaten sustainability of the more than 1,700 Department of Defense (DoD) managed military installations in coastal areas worldwide. Current DoD coastal protection measures, including bulkhead and coastal seawalls, may reflect wave energy, exacerbate flooding, create downstream sediment loss, and restrict water exchange. DARPA’s Reefense program aims to develop novel hybrid biological and engineered reef-mimicking structures to mitigate wave and storm damage and reduce the ecological impact of current coastal protection measures.

 

Sea level rise and wave-induced flooding during increasingly frequent storm events threaten sustainability of the more than 1,700 Department of Defense (DoD) managed military installations in coastal areas worldwide (see: “Military Installations and Sea-Level Rise.” Congressional Research Service. 26 July 2019. https://fas.org/sgp/crs/natsec/IF11275.pdf

Despite previous efforts to implement storm mitigation solutions, damage due to storm surge and flooding continues to impact military infrastructure. Current DoD coastal protection measures, including bulkhead and coastal seawalls, may reflect wave energy, exacerbate flooding, create downstream sediment loss, and restrict water exchange. To protect DoD personnel and infrastructure, DARPA has established the Reefense program, which aims to develop novel hybrid biological and engineered reef-mimicking structures to mitigate wave and storm damage and reduce the ecological impact of current coastal protection measures.

As part of the Reefense program, custom wave-attenuating base structures will promote coral or oyster settlement and growth, which will enable the structures to be self-sustaining and address the infrastructure-related impacts of sea level rise over time. Program performers will employ recent innovations in materials science, hydrodynamic modeling, and adaptive biology to optimize these structures for responding to a changing environment.

“Reefense takes the novel approach of integrating structural engineering, reef health, and adaptive biology to create reef-like ecological systems,” stated Dr. Lori Adornato, Reefense program manager. “These structures will help significantly reduce infrastructure maintenance costs, promote ecosystem health, and strengthen DoD’s ability to maintain its infrastructure and military readiness.”

The five-year program will be divided into three phases, and address three Technical Areas (TA). TA1 will focus on the base structure and component materials to provide immediate wave attenuation and promote the establishment and growth of marine life, TA2 efforts will promote rapid recruitment of the non-reef building organisms needed to protect the reef, and TA3 will focus on adaptive biology for coral and oysters to ensure compatibility with a changing environment for greater long-term resilience. Teams must propose to all three technical areas to develop comprehensive, enduring solutions.

Proposers are expected to select from one of two environment/organism combinations for their envisioned Reefense efforts. While exact site locations have yet to be chosen, it is anticipated that sites on the U.S. Gulf Coast, South Florida and/or the Caribbean regions will likely be considered.

“We see a great potential for the Reefense program and performer teams to collaborate with other government and non-governmental organizations that have interest in coastal protection and improved ecosystem health,” added Adornato. “We encourage potential transition partners to engage early in the process.”

Reefense program requirements specifically exclude the use of genome editing. A forthcoming Broad Agency Announcement will include full program details. It will be posted to beta.SAM.gov.