WithersRavenel worked closely with the Town of Holly Springs and the NCDOT to design the addition of a northbound right turn lane from NC 55 Bypass onto Sportsmanship Way. The proposed improvements included the conversion of a grassy valley median with yard inlets to a raised landscaped median with curb-and-gutter storm sewer. The proposed road widening associated with the project also required the extension of an existing box culvert under NC 55 Bypass.
WithersRavenel designed the retrofit of the storm sewer network to work with the Town’s vision for the intersection and to meet the Town’s and the NCDOT’s design standards. WithersRavenel also completed a hydrologic and hydraulic assessment of the existing box culvert and proposed extension. The resulting design for the extension included the use of a sloped and tapered inlet to improve the inlet efficiency of the culvert and reduce backwater conditions. The ultimate design and associated calculations were reviewed and approved by both the Town and the NCDOT.