Case Study #2 for UTCM Report #08-14-03 "Making Mobility Improvements a Community Asset: Transportation Improvements Using Context-Sensitive Solutions"

1. Project 2
North Central Freeway (US 75) and High
Five Interchange Reconstruction
Dallas, Texas
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2. North Central Expressway
 Constructed 1947 (4-6 lanes)
 Capacity exceeded after about 10
years
 Initial planning for more capacity
 Started in early 1970s
 More lanes in existing ROW
 Double deck (similar to Austin I-35)
 Broadly opposed (twice)
 Noise
 Aesthetics
 Maintenance of traffic concerns
 ROW acquisition
 By 1980, congestion 12 hours/day
NCE near Walnut Hill looking south toward downtown in 1959. Source:
http://www.texasfreeway.com/dallas/historic/photos/images/us75_central_walnut_hill_looking_south_2_1959.jpg
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3. North Central Expressway
 Same segment 29 years later (before improvement)
NCE near Walnut Hill looking south toward downtown in 1988. Source:
http://www.texasfreeway.com/dallas/historic/photos/images/tti_us75_walnut_hill_may_88.jpg
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4. Collaborative Approach – Early 1980s
 North Central Task Force
 City of Dallas
 TxDOT
 Chamber of Commerce
 DART
 Property owners
 Business leaders
 Elected officials North Central Task Force Organization. Source: North
Central Task Force reports
 Initiated North Central Project (~10 miles)
 10 miles
 Collaborative
 Consensus plan
 Meet corridor objectives, concerns
 Led by C of C Transportation Committee chair
 Nationally respected project manager
 Multidisciplinary deign team 4

5. Ultimate Proposal
 8+ lanes
 At-grade and depressed sections
 Extensive retaining wall to reduce
ROW needs
 Cantilevered frontage roads
(some)
 LRT in tunnel under frontage road
 Aesthetics package (renowned
architect) Typical cross-sections: north, central, south
sections
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6. Features –
Before and After
Section of NCE at Northwest Highway interchange showing
existing and improved configurations (visualization).
Source: Regional Mobility Initiatives, NCTCOG, Vol. 11, No.
1, July 1997.
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7. Features
Source: http://www.texasfreeway.com/Dallas/photos/us75/us75.shtml
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8. Features
Source: TTI
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9. Features
DART LRT line at north end of tunnel under NCE. Source: Regional Mobility
Initiatives, NCTCOG, Vol. 11, No. 1, July 1997.
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10. “High Five” Interchange
 Project
 Last part of NCE project
 Followed NCE north and south of I-635
 Delayed due to cost and funding
 Full replacement
Before reconstruction. Looking south on US 75 at I-635. Source: TTI 10

11. Project Components
 Fully directional high speed ramps
 NCE widened to 8 basic lanes
 Accommodate wider I-635
 Include HOV ramps
 Maintain existing number of lanes during
construction
Issues
 Construction duration
 Impact of construction on businesses
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12. CSS Solution
 Collaboratively discuss needs and possible solutions
 Extensive public outreach
 Reduce construction duration
 Innovative construction techniques
 Contractor flexibility to innovate
 Incentives/disincentives
 Night construction
 Off-site pre-casting
 Maintenance of traffic
 Existing number of lanes during day
 Coordinate other improvements with High Five
schedule
Photo: Segment erector technology. Source: http://www.urbantransport-technology.com/projects/dallas_1/dallas_19.html 12

13. Expediting Construction
Erecting bridges by pre-cast sections. Source:
http://www.houstonfreeways.com/modern/dfw_high_five_2003-10-27.aspx
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14. Expediting Construction
Expedited construction while maintaining original number of lanes. Source: Eric Slotboom
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15. Result
Before reconstruction. Looking south on US 75 at I-635. Source: TTI
Source: Google Earth
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16. NCE near downtown in 1958. Source:
http://www.texasfreeway.com/dallas/historic/photos/images/us75_central_n_of_downtown_july_1958.jpg
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