Transcript Slide 1

Draft/Conceptual
Engineering Solutions for
Americans with Disabilities
Act (ADA) Compliance
by the
NYSDOT Pedestrian & Bicycle Program
for
Pro Walk/Pro Bike 2004
September 8, 2004
Goal: Obtain ADA Compliance
for Roundabouts Without
Gridlock.
Engineering A Path To
Accessibility And Safety
1.
2.
3.
4.
5.
6.
7.
8.
9.
Chronology of Major Events.
Prior Research Findings.
Current Research Activity.
Access vs. Safety Dichotomy
Motorist Compliance with/without Signals.
Goals for Optimal Roundabout Conditions.
Draft Conceptual Engineering Solutions.
Next Steps/Implications Beyond ADA
Concluding Observations
Chronology of Major
Events
Building A True Community, Access Board,
PROWAAC, 2001
Draft Guidelines for Accessible Public ROW,
Access Board, 2002
AASHTO Comments submitted, 2002
Roundabout Accessibility Summit, 2002
NCHRP 3-78, Crossing Solutions at
Roundabouts… is expected to begin Fall 2004
Prior Research Findings
Pedestrians with vision disabilities took up
to 6 seconds longer to detect gaps.
Few safe/crossable gaps when traffic is
moderate to heavy.
Difficult using audible cues when traffic is
moderate to heavy.
Difficulty finding intersection, curb ramps,
and splitter islands.
Current Research Activity
NCHRP 3-78, Crossing Solutions at
Roundabouts and Channelized Turn Lanes for
Pedestrian with Vision Disabilities.
National Eye Institute of the National Institute of
Health (on Blind Pedestrian Access to Complex
Intersections).
NCHRP 3-72: Lane Widths, Channelized Right
Turns, and Right Turn Deceleration Lanes in
Urban and Suburban Areas.
NCHRP 3-65: Applying Roundabouts in the US.
Access Versus Safety
Dichotomy – Basic
Comparative Observations
Conventional Intersection
Accessibility
Can use audible cues to
determine gaps.
Crosswalk and ramp more
aligned and predictable.
Signalized stopped phase.
Quiet vehicle/pavement
technologies threaten
adequacy of audible cues.
Roundabout Accessibility
Audible cues only help at
lower volume sites.
Difficult to determine safe
crossable gap.
More circuitous route to
walk to reach crossings.
Continuous vehicular flow,
and no signal stop mode.
Challenging to find the
crossing, island or ramps.
Conventional Intersection
Safety
Up to 24 pedestrian and
vehicle conflict points.
Red light running.
Right-turn-on-red
(RTOR).
Left turns during
concurrent phasing.
Up to 1/3 of crashes at
the green “walk” phase.
Roundabout Safety
1 lane roundabout has
8 pedestrian/vehicle
conflict points.
Splitter island is a
pedestrian refuge.
Shorter/one way
pedestrian crossing.
Lower speed is
enforced by design.
Motorist Compliance
With Or Without Signals
Depend on motorists to stop at red, and yield
before RTOR and left turn movements.
4-way, 2 lane signalized intersection speeds
can still be double roundabout speeds.
Its easier to yield and/or stop traveling at 15 20 mph, than 40 mph.
At 15 - 20 mph, you can’t credibly claim “you
didn’t see them” (the motorist is culpable).
Goals For Optimal
Roundabout Conditions
Obtain full ADA compliance.
Keep traffic calming attributes.
Design speed is self-enforcing.
Works for all users and modes.
Consider all traffic control systems.
Multimodal design is essential.
Consider Methods To
Determine Gaps And WayFinding Needs
Sensors that alert pedestrians (audible
message for “real time/true presence” info.)
whether a safe crossable gap is available.
Detectable manual and/or remote actuated
flashing beacon signals or message boards.
Cane detectable surfaces, curb fencing/edging,
talking signs, GPS, other portable devices, etc.
Audible/tactile cues (locator tones, underfoot
detectable vibrations) to find curb/island, etc.
Sensor/Flasher System &
Outside/Center Edging
Overhead Signs & Flashers
Pedestrian Crossing Control Manual for B.C.
Consider Methods To
Improve Motorist
Compliance
Optimal sight lines at crosswalk/splitter island.
High visibility markings & pedestrian signing.
Speed tables, rumble strips, and increased
deflection to improve yielding.
In-road-lighting systems, light-up bollards,
flashing beacons, message boards, etc.
Automatic in-vehicle warning and breaking
systems for crash avoidance.
Roundabout Speed Tables
In-Road-Lighting System
Pursue Crossable Gaps
Without Gridlock
Alternate crosswalk configurations (off-set,
mid-block, pork-chop, etc).
Calming “green wave” signal progressions for
creating platoons conducive to safe crossable
gaps at roundabout crossings.
Sensor-based “ramp metering” as a means of
creating gaps/providing notice of those gaps.
Criteria for when/if fixed signals and separate
rights-of-way are warranted.
Approach (Ramp) Metering
& Monitoring
Stop & Go Signalization
Draft Conceptual
Engineering Solutions
Draft/Conceptual Baseline
Accommodation For Rural
Single Lane Roundabout
Cut-through splitter islands,
Detectable warnings at crosswalks,
Straight alignments at crosswalks,
Detectable warnings at splitter islands,
Standardized detectable high visibility marking,
Basic lighting at all crossings/open sight lines,
Warning/advance warning & regulatory signs.
Draft/Conceptual Baseline
Accommodation For Urban
Single Lane Roundabout
Baseline accommodations from prior slide,
Sidewalk, curb ramp & way-finding edging,
Human scale/low glare crosswalk lighting,
Rumble strips, beacons, message boards,
Pedestrian warning, gap creation systems,
Stop-go signals/separate ROW if needed.
Draft/Conceptual Baseline
Accommodation For
Multilane Roundabouts
Baseline accommodation from 2 prior slides,
Greater emphasis at crosswalks (pavement
warning text, in-roadway devices & overhead
signing to avoid multiple threat crashes),
Design must avoid speed differentials that
contribute to multiple threats crashes,
If space/budget permits, provide alternative
route or separate ROW for non-motor modes.
Next Steps
Access Board issues a Notice of Proposed
Rulemaking (NPRM) for public comment.
Access Board adopts Accessible Public ROW
Guidelines.
USDOT & USDOJ must adopt Accessible Public
ROW Guidelines for them to become regulation
and be enforceable.
Possible Implications
Beyond ADA
Advancing empirical,
simulation model, and
human subject research.
Benefit access & safety
at roundabouts and
signaled intersections.
Anticipate increased
emphasis and support
for pedestrian travel.
Concluding Observations
Engineering measures
may result in safe access
comparable or better than
signalized intersections.
Thoughtful dialogue and
ongoing research can help
make all transportation
facilities more accessible.
Questions & Comments
Are Welcomed!
For Further Information, Please Contact:
James M. Ercolano, M.S.
Pedestrian Specialist
Phone (518) 485-8291
E-mail: [email protected]
NYSDOT Pedestrian & Bicycle Program
NYSDOT Passenger Transportation Division
50 Wolf Road, POD 54
Albany, New York 12232