Project Info:
Location: Raleigh, North Carolina
Role: Prime
Owner: City of Raleigh
Client: City of Raleigh
Construction Cost: $10,600,000
Services:
- Alternatives Development and Analysis
- Public Outreach/Involvement
- Traffic/Transportation Analysis
- Highway/Roadway Design
- Intersection Analysis/Design
- Roundabout Intersection Design
- Traffic Calming Feature Design
- Construction Phasing Plan Development
- Hydraulic Analysis/Design
- Geotechnical Investigation/Evaluation
- Sedimentation Study/Design
- Landscape Architecture
- Signing Design
- Right of Way Plan Development
- Cost Estimate Development
- Utility Coordination
- Utility Engineering
- Railroad Coordination
- Railroad Crossing Design (At‐Grade)
- Local Municipality Coordination
Carolina Pines Avenue is a two‐lane corridor in a primarily residential area of Raleigh. Although transit routes are operated through the corridor, there are currently no pedestrian or bicycle facilities. Additionally, vehicles using the corridor often travel at unsafe high speeds. To improve the safety and mobility for all corridor users, the City of Raleigh is implementing capital improvements on Carolina Pines Avenue between Lake Wheeler Road and South Saunders Street, including accommodations for pedestrians and bicyclists. Lochner is providing design.
To better control vehicle speeds within project limits, Lochner is proposing traffic calming measures using horizontal deflection methods, such as concrete islands, to divide and slow traffic. Additionally, roundabouts at strategic locations along the corridor are proposed. A traditional roundabout will be constructed at the Carolina Pines Avenue/Granite Street intersection, and a turbo roundabout will be installed at the Lake Wheeler Road intersection, which is in an electric transmission easement where signals are not permitted. The design of a roundabout forces vehicles to travel at a slower speed and minimizes stop‐and‐go movement, creating safer driving conditions, reducing idle time, and resulting in better air quality. Relatively new, the design of a turbo roundabout provides a spiraling flow of traffic, allows for controlled left turns, reduces the number of conflict points, and limits weaving movements inside the roundabout.
Lochner’s design also proposes a six‐foot‐wide sidewalk along the north side of Carolina Pines Avenue and a ten‐foot‐wide multi‐use path for the south side. Because the project crosses an earthen dam for Carolina Pines Lake, a 370‐foot‐long boardwalk structure will provide continuity for pedestrians and bicycles, preserve the integrity of the dam, and reduce construction costs. Additionally, the project area includes an existing at‐grade railroad crossing, which is being upgraded as part of the project. The Lochner team is coordinating with Norfolk Southern on the proposed improvements to develop a crossing that meets their needs and will be constructed without impacting their services lines.