Our firm was selected by the City of Raleigh to provide significant improvements to the stormwater system and open stream channel in Simmons Branch Creek. The area is located along Pineview Drive and Swift Drive, two residential streets adjacent to the stream.

The site’s original stormwater system consisted of circular concrete stormwater pipes and cinderblock box culverts, which are more prone to cracking and water intrusion over time. This increased the risk of failure or sinkholes, creating safety and stability concerns. Due to significant erosion, sections of the stream bank fell within two feet of the curb, further exposing the crossing utilities that served many of the homes in the neighborhood. As a result, residents frequently experienced street and yard flooding, and the water service lines to their homes were constantly at risk of failing. Sinkholes along the cinderblock culverts posed significant safety and maintenance issues for the city. In addition, stream bank erosion often facilitates the buildup of sediment, debris, and pollution, which can significantly impact both the immediate environment and the surrounding basins that Simmons Branch connects to.

We were tasked with replacing and upsizing the existing drainage system to reduce flooding, stabilize stream banks, improve public safety, and address maintenance challenges associated with failing infrastructure. Our design included 790 linear feet (LF) of rectangular concrete box culverts, 650 LF of channel improvements, 1,700 LF of sanitary sewer infrastructure, and 1,200 LF of water main relocations. The water and sewer utilities were buried under the channel or encased completely to increase resilience against storms, reduce conflicts between the main and the stormwater system, and maintain the visual appeal at crossings across the creek.