2 minute read

Wetlands May Be Coastline’s Best Defense Against Storms

RESEARCH PARTNERS

Wetlands May Be Coastline’s Best Defense Against Storms

When civil and infrastructure engineering PhD student Juan L. Garzon came to Mason from Spain, he fell in love with the marshes and wetlands of the Chesapeake Bay. “Many people think of the wetlands in a negative way—as a place full of bad smells and mosquitoes,” says Garzon, “but coastal marshes, among many other things, have the potential to shield communities from storms.”

Hurricanes like Irma, Harvey, Maria, and Sandy remind us every summer how vulnerable we are. These storms can cause huge economic losses and fatalities in coastal communities, he says.

While traditional infrastructures, such as levees and dikes, have been used to protect populations living on the coast, a new approach might be needed because of the threat of rising sea levels and climate change, says Garzon. That is what lead him to begin searching for an environmental solution to coastal fooding.

Among the different alternatives for coastal protection, wetlands might be the most appropriate form of protection.

These ecosystems present two huge advantages over traditional infrastructures. First, they can capture carbon dioxide from the atmosphere and transfer it to the ground, fghting climate change and global warming. Second, through a sedimentation process they can grow vertically, helping to maintain the coastal elevation when the sea level is rising.

Wetlands are the transition space between the sea and the land, and they receive the direct impact of waves and fooding. The complex interaction between waves, currents, tides, and the vegetation growing in wetlands is far from being completely understood. “My research aims to better understand the ability of wetlands in the Chesapeake Bay to reduce the height of ocean waves,” says Garzon.

Wetlands can be used as a natural defense to protect coastal communities from the strong impact of waves. When wetlands food during a coastal storm, waves can travel across land, he says. Without the presence of the vegetation, waves will travel freely along the wetlands, hitting houses and buildings, overtopping coastal defenses, damaging properties, and threatening people’s lives.

Garzon took feld measurements during storm events and discovered that ocean waves are effciently dissipated by the vegetation, and they disappear in less than 200 meters. He also developed a mathematical expression that can predict the wave height decrease inside the wetland for any storm and plant conditions. This expression can be used for coastal engineers when they are designing protection plans against coastal hazards.

“The outcomes of my research promote wetland protection and restoration,” says Garzon. “This will help to fght against climate change and protect coastal populations and therefore reduce our vulnerability against hurricanes.”

––Martha Bushong

Juan Garzon, who graduated in May 2018, worked with associate professor Celso Ferreira’s Flood Hazards Research Lab.

Photo courtesy of the Flood Hazards Research Lab

GIVING

Partnerships with our alumni and friends nurture a spirit of giving.

This article is from: