1. Fordham at Columbia as a Grade-Separated Intersection
Multimodal NC-54 Meeting
May 9, 2017
Fordham at Columbia as a Grade-Separated Intersection
Joe Hummer, Staff Engineer, Mobility and Safety

2. Current Diamond Interchange

3. Improvement Opportunities
Pedestrians
Congestion
Speed control
Progression

4. Grade-Separated Intersection Idea
Sometimes junctions need a bridge
If we build a bridge, we may not need or want a complete interchange
Grade separated intersections = intersections with bridges
All movements signalized
Efficient two-phase two-approach (half) signals
Encourage peds and bikes
Allow four-way progression
Control speeds

5. Concept—Replace Two Three-Phase Full Signals with Six Two-Phase Half Signals
Columbia
Fordham

6. Left Turns From Fordham to Columbia

7. East Intersection

8. North Intersection

9. West Intersection

10. South Intersection

11. Progression through all N-S signals Congestion relief
Potential
Progression through all N-S signals
Congestion relief
Pedestrian crossing simplified with less delay
Two phase instead of three-phase signals
Speed control on Fordham
Need traffic control devices
Need a little pavement
Should be no extra ROW, no utility impact, minimal grading

12. Future Work
Need traffic count, forecast
Quick traffic analysis to see if concept feasible
If feasible, more detailed traffic analysis
Consultations
Design
Construct
Document effects
Look for other places to make similar conversion

13. Thank You! Joe Hummer, jehummer@ncdot.gov, 919-814-5102