#41 times change, people change, transportation needs change - laplante
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John LaPlante, PE, PTOE
Director of Traffic Engineering
T.Y. Lin International, Inc.
ProWalk/ProBike Presentation
Long Beach, California
September 12, 2013
Committing a Lifetime to
Active Transportation
In the beginning…
There were bikes … and people walking
So how did we end up here?
So how did we end up here?
Common Traffic Engineering Myths
• Slower speeds reduce mobility and
increase costs for all vehicles
• Speed limits should be set at the 85th
percentile speed
• Required to design to Level of Service C
for the peak half hour 20 years hence
• Federal highway standards and
guidelines require wide lanes
• Spending for Complete Streets is a luxury
we cannot afford
Common Traffic Engineering Myths
• Slower speeds reduce mobility and
increase costs for all vehicles
• Speed limits should be set at the 85th
percentile speed
• Required to design to Level of Service C
for the peak half hour 20 years hence
• Federal highway standards and
guidelines require wide lanes
• Spending for Complete Streets is a luxury
we cannot afford
Defining Mobility
• Typical experience: – 45 mph speed
– 2 min wait at signal
Defining Mobility
• Viable alternative:
– 2-way progression set for 30 mph
Benefit/Cost Analysis
• Reducing speed from 45 mph to 30 mph – For a 5-mile trip, a 3.33-minute delay
– Assume 30,000 ADT and $20/hr driver cost
– $12.154 million in loss to economy, right?
• Wrong! – Delay for each person is still 3.33 minutes
– Less time than their daily stop for Starbucks
• Community benefit – Slower operating speeds
– Safer and more comfortable ped crossings
Common Traffic Engineering Myths
• Slower speeds reduce mobility and
increase costs for all vehicles
• Speed limits should be set at the 85th
percentile speed
• Required to design to Level of Service C
for the peak half hour 20 years hence
• Federal highway standards and
guidelines require wide lanes
• Spending for Complete Streets is a luxury
we cannot afford
ITE New
Recommended
Practice
Designing
Walkable Urban
Thoroughfares:
A Context
Sensitive
Approach
Sets target speed (desirable operating speed)
as the most important design element
Speed Affects Crash Avoidance
High speeds equate to greater
reaction and stopping distance 7-12 How to Develop a Pedestrian Safety Action Plan – Engineering
Strategies
High speeds lead to
greater chance of
serious injury &
death
Speed Affects Crash Severity
What about the 85th Percentile?
• The 85th percentile is the speed at which 85% of the drivers feel most comfortable driving
• It has nothing to do with the comfort of pedestrians or bicyclists
• It has nothing to do with safety
• It is only based on the ease of writing tickets
However, posting a lower speed limit does not slow cars down
Only designing the street for the target speed can achieve that goal
Common Traffic Engineering Myths
• Slower speeds reduce mobility and
increase costs for all vehicles
• Speed limits should be set at the 85th
percentile speed
• Required to design to Level of Service
C for the peak half hour 20 years hence
• Federal highway standards and
guidelines require wide lanes
• Spending for Complete Streets is a luxury
we cannot afford
Roadway Capacity Analysis
• Designing to LOS C for peak hour means: – Unnecessary pavement, waste of tax dollars
– Increased ped crossing times, thus reducing vehicular movement times
– Increased operating speeds for other 22 hours
ALWAYS design urban roadways to LOS D
Will traffic volumes always increase? Maybe not
Since 2005 US VMT has been flat
17
1,700
1,900
2,100
2,300
2,500
2,700
2,900
3,100
3,300
1985 1990 1995 2000 2005 2010
An
nu
al V
eh
icle
-Mile
s (
Billio
ns
)
Common Traffic Engineering Myths
• Slower speeds reduce mobility and
increase costs for all vehicles
• Speed limits should be set at the 85th
percentile speed
• Required to design to Level of Service C
for the peak half hour 20 years hence
• Federal highway standards and
guidelines require wide lanes
• Spending for Complete Streets is a luxury
we cannot afford
AASHTO: American Association of State Highway and Transportation Officials
ITE: Institute of Transportation Engineers
Nothing in Complete Streets
Conflicts with National Guidelines
Common Traffic Engineering Myths
• Slower speeds reduce mobility and
increase costs for all vehicles
• Speed limits should be set at the 85th
percentile speed
• Required to design to Level of Service C
for the peak half hour 20 years hence
• Federal highway standards and
guidelines require wide lanes
• Spending for Complete Streets is a
luxury we cannot afford
Costs of Retrofitting Urban
Arterials to Complete Streets
• Requires arterial traffic calming/taming:
1. Controlling operating speeds
2. Ped-friendly street crossings
• Geometric issues
• Signal considerations
Costs of Retrofitting Urban
Arterials to Complete Streets
• Requires arterial traffic calming/taming:
1. Controlling operating speeds
2. Ped-friendly street crossings
• Geometric issues
• Signal considerations
• Design to D LOS
• Signal progression
• Narrower travel lanes
• Road diets
• Raised medians and landscaping
• Retain curb parking
Costs to Control Operating Speeds
• Design to D LOS – Less pavement =
less cost
Costs to Control Operating Speeds
• Design to D LOS – Less pavement = less
cost
• Signal progression – Cost to
interconnect
Costs to Control Operating Speeds
News Flash! 10 and 11-foot lanes are just as safe as
12-foot lanes on urban arterials with posted speeds
less than 45 mph
Narrower Travel Lanes
• Design to D LOS – Less pavement = less
cost
• Signal progression – Cost to interconnect
• Narrower travel lanes – Less pavement
= less cost
Costs to Control Operating Speeds
29% reduction in total crashes/mile
Effect of Converting 4-Lane
Roads to 3-Lane and TWLTL
“Classic Road Diet”
Mission District, San Francisco
North-South ADT
0
5000
10000
15000
20000
25000
Dolores Guerrero Valencia Mission S. Van Ness
1998 – before Valencia Road Diet 2000 - after Valencia Road Diet
Handles 20,000 ADT
29
• Design to D LOS – Less pavement = less
cost
• Signal progression – Cost to interconnect
• Narrower travel lanes – Less pavement =
less cost
• Road diets – Install with resurfacing, no
additional cost
Costs to Control Operating Speeds
Continuous raised median
Raised Medians
40% reduction in pedestrian crashes
Median/Parkway Landscaping
• Design to D LOS – Less pavement = less
cost
• Signal progression – Cost to interconnect
• Narrower travel lanes – Less pavement =
less cost
• Road diets – Install with resurfacing, no
additional cost
• Raised medians and landscaping – With
roadway reconstruction
Costs to Control Operating Speeds
Eliminating on-street parking
encourages cars to go faster and
discourages neighborhood business
Retain Curb Parking
• Design to D LOS – Less pavement = less cost
• Signal progression – Cost to interconnect
• Narrower travel lanes – Less pavement = less
cost
• Road diets – Install with resurfacing, no
additional cost
• Raised medians and landscaping – With
roadway reconstruction
• Retain curb parking – No cost, parking meter
revenue
Costs to Control Operating Speeds
Costs of Retrofitting Urban
Arterials to Complete Streets
• Requires arterial traffic calming/taming:
1. Controlling operating speeds
2. Ped-friendly street crossings
• Geometric issues
• Signal considerations
• Tighten corner curb radii
• Corner “pork chop” islands
• Eliminate free flow right turn lanes
• Curb bulb-outs
Pedestrian Friendly Geometrics
Effect of large radius on drivers
They drive fast, ignoring pedestrians
Large corner radii:
•Increase
crossing distance
•Longer signal
time
Tighten Corner Curb Radii
Pedestrian Friendly Geometrics
• Tighten corner curb radii – With roadway
reconstruction
Corner “Pork Chop” Islands
Benefits:
• Separate conflicts &
decision points
• Reduce crossing distance
• Improve signal timing
• Reduce ped crashes (29%)
• Tighten corner curb radii – With roadway
reconstruction
• Corner “pork chop” islands – With
roadway reconstruction
Pedestrian Friendly Geometrics
Eliminate free flow turns across
crosswalks/bikeways Designing Streets for Pedestrian Safety – Interchanges & roundabouts 7-10
… they are difficult for pedestrians to cross… they are difficult for pedestrians to cross
Avoid freeAvoid free--flow movements…flow movements…
Asheville NC
Free Flow Right Turn Lanes
Free Flow Right Turn Lanes
Eliminate free flow turns across
crosswalks/bikeways
• Tighten corner curb radii – With roadway
reconstruction
• Corner “pork chop” islands – With roadway
reconstruction
• Eliminate free flow right turn lanes – With
ramp reconstruction
Pedestrian Friendly Geometrics
Reduce crossing
distance
Improve sight
distance and sight
lines
Prevent
encroachment by
parked cars
Create space for
curb ramps and
landings
Curb Bulb-outs
• Tighten corner curb radii – With roadway
reconstruction
• Corner “pork chop” islands – With roadway
reconstruction
• Eliminate free flow right turn lanes – With
ramp reconstruction
• Curb bulb-outs – With roadway
reconstruction and on-street parking
Pedestrian Friendly Geometrics
Costs of Retrofitting Urban
Arterials to Complete Streets
• Requires arterial traffic calming/taming:
1. Controlling operating speeds
2. Ped-friendly street crossings
• Geometric issues
• Signal considerations
Pedestrian Signal Considerations
• Time signals for 3.5 ft/sec walking speed
• Countdown clocks
• Ped actuated HAWK signals
• Rectangular Rapid Flash Beacon
2009 MUTCD now recommends using a
pedestrian walking speed of 3.5 fps for FDW and
3.0 fps for overall WALK phase
Pedestrian signal timing
Recent studies found that previous 4.0 fps
walking speed based on average walking speeds
(not 15th percentile)
• Time signals for 3.5 ft/sec walking speed –
Signal maintenance
Pedestrian Signal Considerations
50% of pedestrians in the
U.S. do not understand
that “Flashing Don’t Walk”
really means it is OK to
continue walking
So we put signs like this to
“correct” the problem
Effective Communications
Pedestrian count-down signal tells pedestrians
how much crossing time is left
Countdown Clocks
Results from San Francisco:
25% Crash Reduction Factor after
countdown signals installed
Countdown Clocks
• Time signals for 3.5 ft/sec walking speed –
Signal maintenance
• Countdown clocks – Can be added for
roughly $2,000/intersection
Pedestrian Signal Considerations
HAWK (High Intensity Activated Crosswalk)
Also in 2009 MUTCD
HAWK Pedestrian Hybrid Signal
Drivers
see
Beacon
Peds see
Pedhead
• The CROSSWALK STOP ON RED sign shall be used
• There are Guidelines (similar to signal warrants) for
Pedestrian Hybrid Beacons – variables include:
– Pedestrian volume
– Traffic speeds
– Traffic volumes
– Crosswalk length
Excerpts from MUTCD Chapter 4F
For Pedestrian Hybrid Beacons
Speeds exceeds 35 mph
0
100
200
300
400
500
0 500 1000 1500 2000
Major Street - Total of Both Approaches - Vehicles Per Hour (VPH)
To
tal o
f A
LL
Pe
de
str
ian
Cro
ssin
g
Ma
jor
Str
ee
t -
Pe
de
str
ian
s P
er
Ho
ur
(PP
H)
34 50 72 100 Signal Warrant Minimum Pedestrian
Signal warrant
Curves based on
length (see below)
Pedestrian Hybrid Beacon Effectiveness
• Time signals for 3.5 ft/sec walking speed –
Signal maintenance
• Countdown clocks – Can be added for
roughly $2,000/intersection
• Ped actuated HAWK signals – Half the
cost of standard ped signal; lower
warrant
Pedestrian Signal Considerations
Rectangular Rapid Flash LED Beacon
►Beacon is yellow, rectangular, and has a rapid “stutter” flash
►Beacon located between the warning sign and the arrow plaque
►Must be pedestrian activated (pushbutton or passive)
►Studies indicate motorist yielding rates increased from 18.2% to 81.2% for 2 beacons and to 87.8% for 4 beacons
►Interim approval from FHWA in July 2008
• Time signals for 3.5 ft/sec walking speed –
Signal maintenance
• Countdown clocks – Can be added for
roughly $2,000/intersection
• Ped actuated HAWK signals – Half the
cost of standard ped signal; lower warrant
• Rectangular Rapid Flash Beacon - $20K
and no specific warrant
Pedestrian Signal Considerations
• Slower speeds reduce mobility and increase
costs for all vehicles
• Speed limits should be set at the 85th percentile
speed
• Required to design to Level of Service C for the
peak half hour 20 years hence
• Federal highway standards and guidelines
require wide lanes
• Spending for Complete Streets is a luxury we
cannot afford
ALL MYTHS!
Common Traffic Engineering Myths
• Bikes and pedestrians are alternative
transportation modes
• Bikes should only be on low stress
facilities
• Bike boxes are an answer
• Cycle tracks are the ultimate answer
• Cars are the enemy!
Common Nonmotorized Myths
• Bikes and pedestrians are alternative
transportation modes
• Bikes should only be on low stress
facilities
• Bike boxes are an answer
• Cycle tracks are the ultimate answer
• Cars are the enemy!
Common Nonmotorized Myths
is like calling women
alternative men Mark Fenton
Designating peds and bikes as
“alternative transportation”
• Bikes and pedestrians are alternative
transportation modes
• Bikes should only be on low stress
facilities
• Bike boxes are an answer
• Cycle tracks are the ultimate answer
• Cars are the enemy!
Common Nonmotorized Myths
Auto-oriented street: High stress
Four Bicyclist Types*
Bicyclist Characteristics
* Roger Geller, Portland, OR
• Strong & Fearless <1%
• Enthused & Confident 7%
• Interested but Concerned 60%
(Includes children)
• No Way, No How 33%
• LTS 1: Suitable for almost all cyclists, including
children trained to safely cross intersections
(paths, low volume streets).
• LTS 2: Suitable to most adult cyclists but
demanding more attention than expected from
children (bike lanes, sharrows).
• LTS 3: More traffic stress than LTS 2, but less
stress than integrating with multilane traffic (bike
lanes/sharrows on arterials).
• LTS 4: Strong and fearless.
Levels of Traffic Stress (LTS)
Source: Mekuria, Furth & Nixon- “Low-Stress Bicycling and Network Connectivity” – Mineta Transportation Institute, May 2012
It’s okay for young kids to ride on sidewalks
Sidewalks are Low Stress
An adult bicyclist on a sidewalk is not a good sign
A cyclist on a sidewalk interferes with pedestrians
A cyclist on a sidewalk places himself at risk
Especially when riding against traffic!
RELATIVE DANGER INDEX Of various types of facilities
• Major Streets w/o bike lanes 1.28
• Minor Streets w/o bike lanes 1.04*
• Streets with bike lanes 0.5
• Mixed-use paths 0.67
• Sidewalks 5.32
(* = shared roadway)
1.00 = median
Source: William Moritz, U.W. - “Accident Rates for Various Bicycle Facilities” - based on 2374 riders, 4.4 million miles
Provide space on streets …
Bike lanes most
appropriate on urban
thoroughfares
They get you from one
part of town to another
efficiently
Intersections stop or
signal controlled
No point in striping
local streets with bike
lanes
Can be low stress when wide on low speed roads
Provide access to major destinations on arterials
Guide bicyclists into safer behaviors
More visible bicyclists improves motorist behaviors
Advantages of Bike Lanes
Disadvantages of Bike Lanes
Most bike lanes on arterial streets are LTS 3 or 4
Often not enough street width (even with 10-foot
travel lanes)
May require stripping parking (NEVER a good idea)
• Bikes and pedestrians are alternative
transportation modes
• Bikes should only be on low stress
facilities
• Bike boxes are an answer
• Cycle tracks are the ultimate answer
• Cars are the enemy!
Common Nonmotorized Myths
Bike Box
Colored Bike Lane & Bike Box
Allows bicyclists to go before motor vehicles at
signalized intersections
More visible bicyclists improves motorist behaviors
Bicyclists think they are wonderful
Advantages of Bike Boxes
Disadvantages of Bike Boxes
Requires lots of bicycles to gain motorist compliance
Onset of green can lead to blind right turn hooks of
bicyclists approaching from behind
Crash record is mixed, no good data available as of
this time
Not in AASHTO Bike Guide or MUTCD
Merging Bicyclists & Right
Turners Still a Better Idea
Merging Bicyclists & Right
Turners Still a Better Idea
Merging Bicyclists & Right
Turners Still a Better Idea
• Bikes and pedestrians are alternative
transportation modes
• Bikes should only be on low stress
facilities
• Bike boxes are an answer
• Cycle tracks are the ultimate answer
• Cars are the enemy!
Common Nonmotorized Myths
Midblock (LTS 1)
Cycle Tracks
Cycle Tracks
Midblock (LTS 1)
Where a bike signal is required
Cycle Tracks (LTS 1)
Except at intersections
Or a combined bike/right turn lane
Cycle Tracks (LTS 1)
Except at intersections
Or special markings through the
conflict area
Cycle Tracks (LTS 1)
Except at intersections
Very low stress midblock
Encourages bike riding, thereby increasing overall
conspicuity and crash rate reductions
Advantages of Cycle Tracks
Disadvantages of Cycle Tracks
Requires special intersection treatments (signals,
prohibit vehicular right turns or merged right turns)
Not appropriate on streets with driveways
Takes more room (removal of travel or parking lane)
More costly than traditional bike lanes
Not in AASHTO Bike Guide or MUTCD
• Bikes and pedestrians are alternative
transportation modes
• Bikes should only be on low stress
facilities
• Bike boxes are an answer
• Cycle tracks are the ultimate answer
• Cars are the enemy!
Common Nonmotorized Myths
“All roads, streets and
highways, except
those where bicyclists
are legally prohibited,
should be designed
and constructed under
the assumption that
they will be used by
bicyclists.” AASHTO
Bikes Belong
Bikes Belong
“Therefore, bicyclist’s needs should be considered in all phases of transportation planning, design, construction. ,maintenance, and operations.” AASHTO
Cars Also Belong
Wide Bike Lane/Low Speed (LTS 1)
5-foot Bike Lane/30 mph (LTS 2)
Cars Also Belong
5-foot Bike Lane/30 mph (LTS 2)
Cars Also Belong
Cars Also Belong!
H.G. Wells: “When I see an adult on a bicycle,
I realize there is hope for civilization.”
QUESTIONS?
COMMENTS?
CONCERNS?