May 2023: Barbara Doll
NC State University Associate Extension Professor in Biological and Agricultural Engineering
Exploring Natural Infrastructure Strategies in Flood Mitigation
Coastal riverine flooding puts human lives in danger, destroys homes and businesses, and impacts health. It disrupts and damages transportation and infrastructure resulting in road closures. These impacts affect local economies and first responder and emergency response times. Damage and issues as a result of flooding occur most frequently in North Carolina in the coastal flood plains. A recent research study led by Dr. Barbara Doll of North Carolina State University investigates key strategies for improving North Carolina’s flood resiliency by implementing flood mitigation strategies.

In what ways do coastal and riverine flooding impact like the health of residents in North Carolina?
When an individual’s home is flooded, whether they’re going to have to move to another place or repair their house to be livable again, is a tremendous strain. For those who are low-income households, recovery is longer and more difficult and that plays on mental health. Mental health strains and emotional strains lead to poor health in general. People who drown during or after these storms, whether pedestrians or in cars, there’s a very acute impact of human health. Even after the storm, the health of drinking water supplies is contaminated. River water picks up contaminants that negatively human health such as animal waste and chemicals from spills. There are complex and extensive repercussions from flooding.
Why should natural infrastructure practices be a major component in flood mitigation?
The primary reason is that natural infrastructure practices are lower risk while building big levees and dams are high risk and very expensive practices. We’re starting to move away from those practices to more distributed and lower risk ones because we’re in an uncertain climate. We’ve seen where the levees that were built many decades ago now aren’t doing so well because of climate shifts. In addition to lowering risk, there are many added benefits to water quality. It is necessary to think about systems that work when it’s drought, normal, and flood conditions. This is possible natural infrastructure because these systems would be more localized and able to work with adjacent land uses.
Which natural infrastructure practice is the most efficient and realistic for North Carolina?
Wetland restoration, although costly because it requires grading to create an area large enough to hold floodwaters from large storms, is preferable. Wetlands would help not only during flooding events, but during drought as well. Wetlands can be utilized for water storage for agricultural purposes such as crop irrigation. Additionally, because wetlands play a significant role in improving water quality, they would help to address water quality issues from agricultural land in North Carolina. Wetland restoration is the most versatile natural infrastructure option.