Unlocking the Value in Natural and Hybrid Coastal Infrastructure
Coastal climate resilience -
Natural geographic features and hybrid natural and built structures provide a range of valuable services to coastal communities all around the U.S. In effect functioning as infrastructure, naturally occurring marshes, reefs and beaches, as well as “hybrid approaches, such as a 'living shoreline' – a combination of natural habitat and built infrastructure” strengthen coastal communities' resilience to storms, storm surges, flooding and erosion, as well as the broader effects of extreme weather events, rising sea levels and a warming climate, according to results of a just released study from the National Oceanic and Atmospheric Administration (NOAA).
Assessing reports and peer-reviewed studies, NOAA researchers zoomed in on how U.S. coastal communities can enhance and derive greater socioeconomic and ecological benefits from natural and hybrid infrastructure. The study, entitled “Future of our coasts: The potential for natural and hybrid infrastructure to enhance the resilience of our coastal communities, economies and ecosystems” was published in Environmental Science and Policy.
“When making coastal protection decisions, it’s important to recognize that built infrastructure only provides benefits when storms are approaching, but natural and hybrid systems provide additional benefits, including opportunities for fishing and recreation, all the time,” lead author and NOAA National Ocean Service ecosystem science adviser Ariana Sutton-Grier, Ph.D., was quoted in a press release. “Natural and hybrid systems can also improve water quality, provide habitat for many important species, and mitigate carbon going into our atmosphere.”
Strengthening climate resilience in U.S. coastal communities
Storms, flooding and coastal erosion threaten some 350,000 houses, businesses, bridges and other public built infrastructure located within 500 feet of shorelines across the U.S., NOAA highlights. The frequency and intensity of extreme weather events is on the rise, while rising sea levels threaten to contaminate already strained water resources and distribution infrastructure.
Eleven billion-dollar weather and climate disasters occurred in the U.S. in 2012, resulting in 377 deaths and over $110 billion in damages, NOAA report authors point out. While just two were coastal events, among them was Superstorm Sandy, which caused $65 billion of damages – 65 percent of the total. The other, Hurricane Isaac, caused $3 billion in damages.
In terms of damages from natural disasters, 2012 was the second costliest year on record. 2005, year in which four coastal hurricanes contributed to $160 billion in damages, was the costliest.
NOAA's study authors found that both natural coastal structures such as marshes, dunes, sea grass and oyster beds, mangroves and coral reefs, as well as hybrid structures that combine natural and built infrastructure, can provide valuable, at times invaluable, services.
Adapting to sea level rise and a warming climate
Able to adapt to changing weather and climate conditions and “keep pace with sea level rise” lends advantages to natural ecosystems and coastal “infrastructure,” the study authors note. That said, they also conclude that “hybrid approaches, such as combining some habitat restoration with openable flood gates or removable flood walls, provide benefits while also providing more storm and erosion protection than natural approaches alone.
“There is a lot of potential innovation with hybrid approaches,” said Katya Wowk, Ph.D., study co-author and NOAA senior social scientist, was quoted as saying. “Hybrid approaches, using both built and natural infrastructure, often provide more cost-effective flood risk reduction options and alternatives for communities when there is not enough space to use natural coastal protection alone.”
“Coastal resiliency and disaster risk reduction have become a national priority, and healthy coastal ecosystems play an important role in building resilient communities,” added Holly Bamford, Ph.D., acting assistant secretary of commerce for conservation and management at NOAA, and the study's third co-author.
“We know that sea levels are rising and that coastal communities are becoming more vulnerable to extreme weather- and climate-related events. Now is the time to invest in protection to secure our coasts, but we need to make those investments wisely and with a full understanding of the costs and benefits of different approaches.”
*Image credits: NOAA, “Future of our coasts: The potential for natural and hybrid infrastructure to enhance the resilience of our coastal communities, economies and ecosystems”