Post on 28-Jul-2020
6/14/2012
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Planning Urban Roadway SystemsPlanning Urban Roadway Systems
Don Samdahl
Chris Breiland
• Review the ITE Report “Planning Urban
Roadway Systems”
• Understand the principles of planning urban
roadway systems
• Define a layered network
• Show how layered networks and MMLOS fit
together
Presentation
A Long History
Planning Urban Roadway Systems
3
Chapters
1. Introduction
2. Context for roadway systems
3. Principles of roadway systems
4. Roadway system characteristics
5. Planning process
6. Special issues
7. Implementation
Planning Urban Roadway Systems
• Planning = Focus on overall planning
• Urban = Focus on urban and suburban
• Roadway = Entire public right-of-way;
multimodal emphasis
• Systems = Look at entire network; holistic view
Planning Urban Roadway Systems Building Upon Urban Thoroughfare RP
• Focused on Corridors
• Context Sensitive Design
• Streetscape/Intersection
• Best Practices Street Design
• Focused on Networks
• Balanced for all modes
• Best Practices for Networks
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Traditional Conventional
Context
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• Fragmented systems
• Major roadways
overloaded
• Limited multimodal
provisions
Consequences
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• Limited opportunities to
reconfigure network
• Constrained ROW and
geography
• Public doesn’t understand value
of network connectivity
• Outdated codes
• Reactive rather than proactive
planning
Planning Challenges
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Balanced, layered multimodal networks that safely serve people of all ages and abilities, including pedestrians, bicyclists, transit riders, and motorists.
Principles 1 & 2: Balance
Principle 3: Connectivity
� Overall less capacity
� Higher number of crashes*
� Not ped/bike/transit friendly
� Slower emergency response**
� Overall more capacity
� Fewer, less severe crashes
� Multiple direct travel options
� Ped/bike/transit friendly
� Fewer/shorter auto trips
� Faster emergency response**Sources: * Research in 24 cities, 130,000 crashes
** City of Charlotte, NC
Conventional:
Disconnected, Separate Uses
Traditional:
Connected, Mixed UsesHave a high degree of connectivity to help provide multiple routing options for users (including emergency services).
Challenges of a Connected Network:
• Streets have been there for a
long time
• Right-of-way is constrained
• Street connections difficult to add
– Natural barriers
– Residents & developers oppose
connections
• Outdated codes
Solution: connect to the degree practical – at least non-motorized
Tra
dit
ion
al
Co
nv
en
tio
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Principle 3: Connectivity
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Appropriate to the land use patterns and urban form that are served.
Principle 4:
Appropriate Network Density Treat roadways as public spaces that influence urban environments.
Principle 5: ROW=Public Realm
Use all of the public right-of-way
To relate to private development
Go beyond the street
Be environmentally and fiscally responsible.
Principle 6: Sustainable Functional Classifications Don’t Always
Work� Context Factors
� Land Use Type
� Development Densities
� Form (e.g. height and setback)
� Corridor Users
Conventional
New Typologies
Layered Networks
� Complete Streets =
accommodate all modes
if possible
� Layered Networks =
provide priority to
particular mode to
improve efficiency and
safety
� Identify integrated
modal network
Layered
Networks
Have Been
Around for
Awhile
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Transit Networks
Connectivity - Connected roadways allow for a variety of transit routings, as well as
better pedestrian connections to access stops.
Roadway Spacing - Within a connected roadway network, the ideal spacing for transit-compatible roadways is one half mile
within a grid pattern to allow everyone to be within a quarter mile of transit.
Roadway Design - Improved access to transit, combined with a pedestrian oriented environment.
Land Use Planning - Planning and regulations to promote clustering of
development and mixed use Transit Oriented Development.
Bicycle Networks
� Network needs a variety of bike
facilities for different bike users
A: Advanced, experienced
B: Basic, most potential
C: Children, less confident
� Network may include
� Bike Routes (share the road)
� Bike boulevards (minor streets)
� Bike lanes
� Trails and pathways
� Type of rides
� Time of day
� Trip purpose
� Weather
Route Selection Factors
Layered Network Layered Network
Network Spacing
� Three principal determinants of roadway spacing
� Trip density
� Travel characteristics
�Design and physical characteristics
� Roadway Networks should consider adequate spacing to
accommodate all modes of transportation
Different treatments at different locations23
Charlotte, NC Access Route for FS 31
~1½ miles
~½ mile
300’ gap in road
NCourtesy of Danny Pleasant, AICP Charlotte Dept of Transportation
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0
5,000
10,000
15,000
20,000
25,000
30,000
Fire Station
Station 2
Station 15
Station 14
Station 24
Station 22
Station 19
Station 9
Station 31
Station 31 w/Shelley
Greater connectivity Less connectivity
Charlotte, NC Households per Fire Station
Courtesy of Danny Pleasant, AICP Charlotte Dept of Transportation25
Balance and prioritize design to meet street’s purpose
Multi-Modal Quality of Service
Highway Capacity Manual 2010
• Comfort based
• LOS based on:
� Autos: quality of service
� Transit: quality of
service; comfort
� Bikes: comfort
� Pedestrians: comfort
• Accounts for:
� Street cross-section
oTravel lanes
oBike lanes
oParking
o Landscaping
o Sidewalk
oBus Shelters
� Speed of traffic
� Vehicle volume (ADT)
HCM 2010 MMLOS Case Study:
Tukwila, WA• Citywide calculation of
pedestrian, bicycle, and
auto LOS
• Grant funded
• More than 70 auto and
bicycle segments and
more than 350
pedestrian segments
• Extensive data collection
• Custom GIS application
Pedestrian LOS Bicycle LOS
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Auto LOS Lessons Learned
• LOS results generally met expectations,
particularly for bicycles
• Some surprises: Lack of a sidewalk did not
lead to automatic LOS F
• Difficult to score LOS A or LOS F
• Not sensitive to urban form/adjacent land
uses
• Not tuned to identifying mitigations
• Need for clear policy guidance and design
standards
Need for Clear Policy Multi-Modal Quality of Service
One Idea: Person-Delay
Illustration of Alternative 5 (bicycle/pedestrian bridge) and analysis by mode
0
10
20
30
40
50
60
70
Se
co
nd
s
HCM Intersection LOS = C
PM Peak Hour Delay
Option 5 28.7 29.8 64.2 15.1 28.1
Vehicle Buses Pedestrian Bicycle Average
Person Delay
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City of Burien, WA
Layered Modal Networks and MMLOS
Auto / Truck
Priority
Routes
LOS E- Downtown Burien
LOS D- Vehicle Priority Roadways
LOS C- Other Roadways
Transit
Priority
Routes
Emphasis
•All day, frequent transit service
•Transit stop
amenities•Minimal transit
delay
•Good pedestrian access
Pedestrian
Priority
Routes and
Areas
Needs:
•17-18 miles of
new sidewalks on
arterials and
collectors
•Wide shoulders
on local streets
where possible
Bicycle
Priority
Routes
Emphasis
•Use of local streets and
selected arterial
corridors•Adequate
treatments at
intersections•Limited stop
frequency
Chapter 5: Planning Process
Planning Issues
• Environmental Sustainability
• System Continuity
• Travel Demand Management
• Traffic Operations/ Control
• Economic Impacts
• Network Resiliency
• Fiscal Considerations
• Capacity for Vehicular Travel
Demand
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Chapter 6: Special Issues
• Suburbanization of Rural Roadway Systems
• Urbanization of Suburban Systems
• Traditional Neighborhood Development (TND)
• Transit-Oriented Development (TOD)
• Junctions and Intersections (signals, roundabouts)
• Traffic Calming
• Road Dieting
• One-Way and Two-Way Streets
• Freeways, Surface Streets, & Service Roads
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Traditional Neighborhood Development
• Design buildings, site, streetscape, and streets as one
• Shared use = multimodal with ped/bike emphasis
• Low speeds
• High connectivity
Illustration: LSL Planning, Inc.
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Transit-Oriented Development
• Networks influence ridership
• Transit priority operations/design
• Pedestrian connectivity and
crossings
• Bike accommodations
• Parking management
• Balanced multi-modal system
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Traffic Calming & Road Diets
• Retrofit vs. built-in
• Replace facility-oriented
planning with a system-
oriented planning effort
• Anticipate impacts on
adjacent facilities and other
modes
• Assess and mitigate impacts
across the multi-modal
system
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Two-Way
• Less capacity
• More crashes
• Lower speed
• Better wayfinding
• Conversion expensive (signals)
One-Way v Two-Way (Lansing, Oakland-Saginaw)
Existing: One-way
Illustration: LSL Planning, Inc.
One-Way• More capacity
• Fewer crashes• Higher speed
• Complicates wayfinding
Two-way Conversion
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Planning for the Freeway Interface
• Functional area of the interchange
• Arterial spacing
• Access management
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We’ve Come a Long Way
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