BAE-designed stormwater wetland earns national construction award

A large-scale water quality project in New Bern, designed by members of N.C. State’s Department of Biological and Agriculture Engineering (BAE), has received national recognition for its construction. Cape Fear Precast LLC of Jacksonville was awarded second place for a local project in the National Precast Concrete Association’s Creative Use of Precast (CUP) Awards at the NCPA’s January trade show in Indianapolis, Ind.

The Jack Smith Creek Stormwater Project, one of the largest stormwater retrofits in the state, was designed by Cooperative Extension’s BAE Stormwater Group in the College of Agriculture and Life Sciences and involved the construction of a stormwater wetland to capture and treat runoff from a large watershed in New Bern. The innovative project can capture and treat the runoff from more than 1,000 acres of residential and commercial property.

The CUP Award recognizes those projects promoting innovative and cost-saving advantages of precast concrete. The W-shaped precast concrete outlet weir for the project, constructed by Cape Fear Precast, is modeled after a labyrinth weir design concept, said Kris Bass, professional engineer and BAE Extension associate.

“The ‘W’ shape creates more flow length in a smaller width than a traditional spillway. The design also incorporates flashboard risers that provide flexibility for controlling water levels in the wetland,” Bass explained. “This design and precast construction approach maximized control over critical features and created an efficient and economical installation in a challenging setting.”

BAE became connected to the project “through a grant with the N.C. Ecosystem Enhancement Program, where we identified over 20 potential water quality projects in the Neuse River Basin,” said Bass.

“The Jack Smith Creek Wetland project was selected for implementation due to its innovative approach and regional scale. BAE Extension was hired to lead the design work and development of a research effort at the site.”

Bass noted that the size and complexity of the project made cooperation with project stakeholders critical. “Extension was able to help foster partnerships with the City of New Bern, Clean Water Management Trust Fund, and several government agencies that have all contributed to the project.”

While the project construction was completed in December of 2012, Bass said that BAE is currently installing monitoring equipment on-site to collect water quality samples. “Final planting is scheduled for the spring of 2013, and we should be getting some results back by the end of the summer,” he said.

The project is also intended to set a new standard for treating stormwater at a watershed scale and be an education center for design and construction of best management practices in a coastal environment, according to the award write-up.

“Watershed scale stormwater projects have been successful in other areas and are gaining momentum in North Carolina,” Bass said. “The research that results from this project will not only expand the knowledge base in stormwater treatment, but also provide guidance on how to develop water quality goals balanced with ecological services and surrounding environments.”— Terri Leith