1. Synthesis of Recent & Ongoing Studies: Accessibility and Pedestrian Safety at Roundabouts
Andrew T. Duerr, P.E. Northeast US Roundabouts Peer Exchange July 7, 2010

2. Towson Roundabout 1st Urban Roundabout Heart of CBD
High Vehicular & Ped Volumes

3. Historical Perspective
Based Largely on European Experience
NCHRP Synthesis 264 (1998)
Roundabouts safe for Pedestrians because:
Low Speeds
Shorter Crossing Distances
Fewer Conflict Points
2000 FHWA Roundabouts: An Informational Guide
Maintains prior assumptions
The differences between modern roundabouts and traditional intersections controlled by traffic signals and stop signs have important implications for blind pedestrians. While some of these implications are not yet well understood, they must be considered by any transportation engineer or planner whose goal is to create an accessible pedestrian environment.

4. Back to Towson Located near Balt. Co. Commission on Disabilities
CMCB files Complaint to DOJ
DOJ defers to FHWA
American Council for the Blind Continues to Seek Roundabout Moratorium
The differences between modern roundabouts and traditional intersections controlled by traffic signals and stop signs have important implications for blind pedestrians. While some of these implications are not yet well understood, they must be considered by any transportation engineer or planner whose goal is to create an accessible pedestrian environment.

5. Back to Towson FHWA Finds in Favor of SHA SHA offers Concessions
Improved Wayfinding
Detectable Warning Surfaces
APS at Signals near the Roundabout
Access Board begins to Focus on Roundabouts (1999)
The differences between modern roundabouts and traditional intersections controlled by traffic signals and stop signs have important implications for blind pedestrians. While some of these implications are not yet well understood, they must be considered by any transportation engineer or planner whose goal is to create an accessible pedestrian environment.

6. Accessibility Research
1999 Western Michigan/Vanderbilt
3 roundabouts in MD (including Towson)
3 roundabouts in Tampa, FL
2000 National Eye Institute Study (NEIS)
2001 National Institute on Disability & Rehab Research
2005 Human Factors Study
2006 FHWA Pedestrian Access to Roundabouts
The differences between modern roundabouts and traditional intersections controlled by traffic signals and stop signs have important implications for blind pedestrians. While some of these implications are not yet well understood, they must be considered by any transportation engineer or planner whose goal is to create an accessible pedestrian environment.

7. Accessibility Research
Summary of Findings –
Poor Yield Rates – Unsignalized Locations
Noise makes Aural Gap Detection difficult
Identifiable Gaps may be Infrequent
Visually Impaired Pedestrians experience 3s Delay (compared to Sighted Peds)
The differences between modern roundabouts and traditional intersections controlled by traffic signals and stop signs have important implications for blind pedestrians. While some of these implications are not yet well understood, they must be considered by any transportation engineer or planner whose goal is to create an accessible pedestrian environment.

8. Access Board Perspective
Accessibility is a Civil Right
Safety ≠ Accessibility
Courts finding 2005 Draft PROWAG to be Best Available Guidance

9. Pedestrian Safety Research
2006 NCHRP 562: Improving Pedestrian Safety at Unsignalized Crossings
2007 NCHRP 572: Roundabouts in the United States
TØI Report 1009/2009
Subjective and Objective Safety: The Effect of Road Safety Measures on Subjective Safety among Vulnerable Road Users
Institute of Transport Economics, Norway
The differences between modern roundabouts and traditional intersections controlled by traffic signals and stop signs have important implications for blind pedestrians. While some of these implications are not yet well understood, they must be considered by any transportation engineer or planner whose goal is to create an accessible pedestrian environment.

10. NCHRP 562 Improving Pedestrian Safety at Unsignalized Crossings (2006)
Recommend Treatments for:
Pedestrian crossings
High speed, high volume roadways
Unsignalized intersections
Recommend Modifications to MUTCD Pedestrian Signal Warrants

11. NCHRP 562 Treatment Categories Marked Crosswalk
Enhanced, High Visibility, or Active When Present devices
Red Signal or Beacon Device
Conventional Traffic Signal

12. NCHRP 562 Findings & Conclusions Crossing Treatment Affects Compliance
Only Signals > 95% Compliance Rate
Other Factors Affect Compliance
Width, Speed & Environment
1-Lane Roads – Compliance > 75%
2-Lane Roads – 30% to 100%

13. NCHRP 572 Roundabouts in the US (2007)
No Substantial Safety Problems Found
Non-Yielding Rate 43% on 2-Lane Legs
Additional Changes required to Improve Yield Rates
Design
Operational
Enforcement & Education

14. TØI Report 1009/2009
Objective (Real) Ped Safety ↑ Subjective (Perceived) Ped Safety ↓

15. On-Going Research
NCHRP 3-78: Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities
Golden, Colorado
Oakland County, Michigan
Andy turns over presentation to Mike

16. NCHRP 3-78
Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities
Objectives:
Identify/Test Treatments
Analysis Framework
Means to Extend Findings
Expected Summer 2010

17. NCHRP 3-78 Study Involved: Single-Lane Roundabouts
Two-Lane Roundabouts
Channelized Turn Lanes

18. NCHRP 3-78 4-Step Analysis Framework: Crossing Opportunity Criterion
Crossing Opportunity Utilization Criterion
Delay Criterion
Safety Criterion

19. NCHRP 3-78 Draft Findings: CTL’s are Challenging
Low Speed S/L Roundabouts are Accessible given Certain Conditions
Pedestrian Hybrid Beacons & Raised Crosswalks show Promise at 2-Lane Roundabouts
2-Lane Roundabouts are Challenging w/o Additional Treatments

20. NCHRP 3-78 Future Research: Expand Number of Field Study Sites
More Detailed Look at CTL’s
Investigate Impact of Education
Expand Study of Treatments at 2-Lane Roundabouts
Improve Field-Based Risk Performance
Auditory Environment

21. Andrew T. Duerr, P.E. aduerr@rkk.com
Synthesis of Recent & Ongoing Studies: Accessibility and Pedestrian Safety at Roundabouts
Andrew T. Duerr, P.E.

22. Eliminate/Reduce Conflict
Grade Separation
Simplify Geometry
Eliminate or reduce entry/exit lanes
Reorient pedestrian networks away from Roundabout

23. Minimize Pedestrian Exposure
Simplify Roundabout Geometry
Geometric Improvements
Bulb outs
Raised cross walks
Buffer Strips between Sidewalk and Roadway
Low Speed Design
Signalized Crossings
ITS Solutions
Police Enforcement

24. Improve Gap Detection ITS Solutions
Treatments that Provide Audible Cues
Shift Crossings Downstream from Exits