April 2023: Miyuki Hino

UNC-Chapel Hill Assistant Professor in the Department of City and Regional Planning

Understanding Sunny Day Flooding in North Carolina

“As we invest in more climate-resilient communities, it is critical to use the best possible evidence on the impacts of flooding, today and in future climates, to maximize the effectiveness of those investments.”

Miyuki Hino

Prior to joining UNC-Chapel Hill, Hino was a postdoctoral researcher at the University of California, Berkeley, and received her Ph.D. in Environmental Science and Management from Stanford University. She has expertise in climate change impacts and adaptation, with a focus on extreme weather events and natural disasters.

What is the goal of your research on communities that experience sunny day flooding in the long run and what is the big solution?

We are a group of researchers from the University of North Carolina at Chapel Hill and North Carolina State University that collaborates with communities to measure, model, and better understand the causes and impacts of chronic coastal flooding in North Carolina.

Through our customized flood sensors and models, we are working with communities to help them plan for the future by identifying how often chronic floods occur, why they occur, where flood risk is highest, and how flooding may change in the future.

We currently have sensors deployed in Beaufort, Carolina Beach, and New Bern, NC. We work with our partner communities to identify locations that experience chronic flooding. Our team then installs water level sensors in stormwater drains and traffic cameras on nearby light posts.

The underground water level sensors help us monitor water levels even if they are not high enough to flood the road – this helps us estimate how sea level rise will impact chronic flooding in the future. Our traffic cameras help verify roadway flooding by taking pictures of the roadway every 6 minutes.

Flooding is already occurring dozens of days each year in North Carolina’s coastal communities. Moreover, flooding occurs more often than tide gauge-based proxies would suggest. In our initial deployment in Beaufort, NC, we detected water on the roadway 24 times in five months. 25% of those events were due to combined rain and tidal forces and would not have been detected by tide gauges.

By more accurately measuring how often these floods occur and what causes them, we can better diagnose the impacts they have on people and businesses and how that might evolve due to climate change. As we invest in more climate-resilient communities, it is critical to use the best possible evidence on the impacts of flooding, today and in future climates, to maximize the effectiveness of those investments.

What are some of the most effective strategies for reducing the impacts of sunny day flooding, and how can these strategies be implemented at the local level?

There are a range of potential solutions for managing coastal flood risk, and there is no one-size-fits-all solution. Funding is a definite challenge, especially for smaller towns and rural areas that have less capacity to apply for and administer big infrastructure grants. While there are short-term costs for investing in upgrading infrastructure or doing wetland restoration to reduce flood frequency, there are also immediate benefits – when roads are underwater on a monthly basis (or more often, as we see in our partner communities), that affects the ability of kids to get to school, customers to get to businesses, patients to get to medical care. So, understanding the impacts of these chronic events can help policymakers advocate for investments that increase the climate resilience of their communities.