Stormwater solutions for North Carolina

Stormwater pollution is the number one threat to coastal water quality in North Carolina, where it contributes to beach closures, impacts tourism, and interrupts shellfish harvests. Rapid urbanization, population growth, and a shifting climate have all converged to make it increasingly difficult for the state’s communities to reduce the volume of stormwater washing over landscape and protect water quality. Excess runoff also leads to street flooding that ranges from being a nuisance to a danger to public safety. A team led by the North Carolina reserve, the North Carolina Coastal Federation, and the University of North Carolina Wilmington recently collaborated with local communities, nonprofits, and state agencies to reduce the volume of polluted stormwater runoff in southeast coastal North Carolina.

Project Impact

This project resulted in the design and installation of a series of stormwater reduction measures within the Town of Wrightsville Beach and City of Wilmington. The retrofits aimed to reduce the volume of stormwater draining from the nearby development and roadways into the adjacent coastal waters. The measures directed runoff from the roadways to landscaped areas so that the polluted runoff could soak into the ground rather than flow through a pipe directly to the stormwater outfalls. Pre- and post-monitoring of the demonstration sites indicated that a majority of the retrofit sites resulted in a 50 to 90 percent reduction in stormwater volumes within the watersheds.

How it worked

This project built on an eight-year effort to address water quality issues in North Carolina’s Masonboro Sound. The North Carolina reserve leveraged that work by collaborating with the North Carolina Coastal Federation, the University of North Carolina Wilmington, state and local agencies, municipalities, development professionals, and homeowners to implement effective stormwater management techniques to improve coastal water quality.

Using collaboration and watershed restoration plans to frame the project, the team demonstrated, monitored, and shared various approaches to reducing stormwater volume in different contexts. They installed infiltration sites and retrofitted existing infrastructure at targeted sites within the project area. These projects increased the amount of stormwater that infiltrates into the ground and reduce the volume flowing into coastal waters.

The team involved stakeholders throughout the project and hosted interactive trainings for stakeholders, including trips to project sites. These events allowed stakeholders to develop an increased understanding of, and support for, the project and stormwater management practices. It also informed the design of the best practices guide and stormwater calculator generated by this project.

Resources

The project generated tools and resources that can be used by communities interested in implementing and assessing various stormwater reduction techniques: