Enhancing Flood Resilience and Community Connectivity Through Floodplain Culvert Design in a Downtown Setting
Emily D. Brown, PhD, PE, TSP
Freese and Nichols, Inc.
Raleigh, NC
The City of Sanford, North Carolina, in partnership with Freese and Nichols, Inc. (FNI), is implementing a comprehensive flood mitigation and stream restoration project along Little Buffalo Creek to address chronic flooding, ecological degradation, and limited pedestrian connectivity in an economically disadvantaged neighborhood near downtown.
The first phase of the project centers on the design and installation of a new floodplain culvert constructed adjacent to two existing 10'×10' box culverts beneath a 40‑foot embankment. Positioned at a higher elevation, the new culvert is engineered to intercept overbank flows during severe rainfall events, reducing water surface elevations by up to three feet during the 100‑year storm in key locations. Beyond flood reduction, the culvert is designed to serve dual purposes—conveying stormwater during wet weather while providing a pedestrian passageway during dry conditions. This approach supports the City’s vision for improved connectivity to a future downtown park and farmer’s market, integrating flood mitigation with community enhancement.
The second phase of the project is the restoration of 2,300 linear feet of Little Buffalo Creek located immediately upstream of the culvert. This design incorporates stream re-alignment, in-channel structures and floodplain reconnection within an urban watershed. Design considerations included multiple utility crossings and conflicts, industrial infrastructure conflicts, power pole relocation, coordination with a concurrent sewer line project, and roadway crossings. The stream will be a primary feature within the future downtown park and was designed in a way to facilitate community interaction while also achieving ecological uplift and habitat improvements.
This presentation will highlight the project’s integrated engineering and ecological design, the measurable flood reduction benefits, and the strategic project approach that enabled the City to advance a transformative, resilient investment for its downtown community.
About Emily D. Brown, PhD, PE, TSP
Emily Brown is an Associate and Project Engineer with Freese and Nichols in the firm’s Raleigh, North Carolina office. She has over 12 years of experience specializing in stream restoration and stormwater design, water quality testing and monitoring, environmental assessments, soil and water quality analysis, fluid mechanics, and floodplain modeling. Her work includes supporting communities with integrated flood mitigation and stream restoration solutions, such as designing floodplain culvert systems that reduce flood impacts, improve ecological function, and enhance community connectivity. Emily completed her PhD at North Carolina State University, where she studied long-term riverbank erosion rates associated with stream restoration projects, research that informs her applied work on resilient floodplain and channel design.
https://www.linkedin.com/in/emily-brown-phd-pe-envsp-cfm-tsp-094a111a/