Title: John V' Thomas, PhD
1Transportation Policy and Placemaking in Tysons
Corner
John V. Thomas, PhD US EPA, Office of Policy
Economics and Innovation June 26th, 2007
2The Core Transportation Issues
- Street Design Challenges
- Accommodating traffic while creating a high
quality pedestrian environment - Addressing assumptions about technical standards
- Analytical Challenges
- Forecasting the baseline traffic
- The net effect of a new land use and transit
environment is a difficult analytical question - Appropriately evaluating the tradeoffs
- Metrics are key
- Details matter
- Finding creative solutions
3Design Challenges
4Context Sensitive Street Design
5Evaluating Cross-Sections
6Design Tradeoffs
- Parking
- Sidewalk Width
- Vehicle Capacity
- Large Vehicle Accommodation
- Pedestrian Crossing Width
- Left turn lanes
- Landscaped Median
- Pedestrian Amenities
- Reduced Speeds
- Minimize Right of Way Acquisition
Across the planning area, the relative weight
assigned to each criteria will vary
7Why Design Speeds are Critical
Source- ICF International, Spokanes University
District Policy Options for a New Urban Center.
Based on data from Karger, Teige et al (2000)
Relationship between impact velocity and
injuries in fatal pedestrian-car collisions
International Journal of Legal Medicine.
8Innovative Ways to Minimize Tradeoffs
- Better crossing conditions across major roads
- Curb bump-outs at key intersections
- Median space as a pedestrian refuge
- Flexible Infrastructure
- Mountable medians and curbs
- Access management and parallel routes
9Curb Bump-out
10Median Refuge
11Design Details Matter
12Mountable Median
13Some Relevant Examples
- 28th Street Boulder, CO
- 30,000 to 50,000 vehicles per day
- Up to 7 lanes
- Multi-year redesign effort
- http//www.bouldercolorado.gov/files/Transportatio
n/Projects/28th_tnp.pdf - El Camino Real San Mateo County, CA
- Route 29 Trenton, NJ
14El Camino Redesign
Source Marcy McInelly, Urbsworks and Phil
Erickson, Community Design Architecture
15El Camino Redesign
Source Marcy McInelly, Urbsworks and Phil
Erickson, Community Design Architecture
16Source Marcy McInelly, Urbsworks and Phil
Erickson, Community Design Architecture
17Source Marcy McInelly, Urbsworks and Phil
Erickson, Community Design Architecture
18Source Mark Stout NJ DOT, Smart Growth and Smart
Transportation, The NJDOT Experience
19Source Mark Stout NJ DOT, Smart Growth and Smart
Transportation, The NJDOT Experience
20Source Mark Stout NJ DOT, Smart Growth and Smart
Transportation, The NJDOT Experience
21Source Mark Stout NJ DOT, Smart Growth and Smart
Transportation, The NJDOT Experience
22Source Mark Stout NJ DOT, Smart Growth and Smart
Transportation, The NJDOT Experience
23Source Mark Stout NJ DOT, Smart Growth and Smart
Transportation, The NJDOT Experience
24Source Mark Stout NJ DOT, Smart Growth and Smart
Transportation, The NJDOT Experience
25Analytical Challenges
26Forecasting Future Traffic Critical Questions
- New development new trips
- What share will be by car?
- What policies would increase transit use,
walking, and biking?
27How will greater accessibility, diversity of
activities and better urban design change trips
currently made within Tysons?
Source Lewis Grim, Cambridge Systematics,
Presentation to the Tysons Corner Coordinating
Committee (2005)
28Evaluation Metrics
- Intersection Level of Service (LOS) for vehicles
is the most common metric - Butit presents a limited picture
- Corridor LOS, corridor travel time, or volume to
capacity measures are somewhat better - Other more comprehensive measures are still in
very early stages of development
29Pedestrian Level of ServiceFlorida DOT example
- Sidewalks (10 points)
- Continuous on one side 4
- Both sides 6
- At least 5 ft 1
- More than 5 ft 2
- Off street parallel trail 1
- Conflicts (4 points)
- Medians 1
- Access management 1
- Reduced turn conflict 0.5
- Amenities (2 points)
- Buffer gt 3 ½ ft. 1
- Shade trees 0.5
- Benches 0.5
- Traffic Flow (2 points)
- LOS E/F gt 6 lanes 0
- LOS D lt 6 lanes 1
- LOS C lt 6 lanes 2
30Other design concepts
31Thinking out of the box
Source City of El Cerrito, CA
32Rail ROW Could Double as a Greenway
33Source Teri Musser, Charlier Associates