CASEY ARBORWAY PROJECT
DAG Traffic Primer
May 24, 2012
Today’s Agenda
1. Previous Traffic Analysis Summary
2. Updates Post Planning Phase
3. Signal Coordination
4. Parking Supply
5. Transit Service and Accommodations
6. DAG #3: Mobility, Monday, June 18, 2012
Topics Requested
•Key Assumptions in Traffic Analysis
•Traffic Calming
•Level of Service (LOS) & Queue Results
•Right Turn Treatments
•Traffic Operations
•Pedestrian Crossings
•Transit Accommodations
•Emergency Response Times
•Alternative Routes
Specific Questions
1. Future queue lengths at key intersections
2. Pros and cons of slip lanes and pork chops
3. Signal timings, particularly for pedestrians
4. Explanation of the key assumptions that feed into
traffic analyses
5. Explanation of how buses coming from the east
(Dorchester and Mattapan) will be accommodated
DAG Welcome Questions
Topic
Response
How to calm traffic with wide median
DAG #3
Rights on Red Allowed
Design allows but
requires further
discussion on DAG #3
Level of Service (LOS)
Presentation today
LOS with 2-lanes in each direction
DAG #3
Location of Pedestrian and bike paths
DAG #3
Path Analysis for all modes – Experience Presentation today
of Corridor
DAG Welcome Questions
Topic
Response
North/south and east/west traffic flows
Clarify
Alternative Regional Routes - Walk Hill?
Clarify – Design or
Construction Phase?
Parking – loss of off-street impacts on
design
Presentation today
Emergency Response during Construction
DAG #4
24 hour review of traffic volumes (peak and
non-peak)
Presentation today
Previous Traffic Analysis
Summary
A Look Back
Early in the Project
Strong community directive to
study and fix the surface street
network regardless of a bridge or
at-grade replacement alternative
Key Assumptions in
Traffic Analysis
Top 5 Areas of Concern Today
2035 Multi-Modal Traffic Operations
• Address local surface system and
intersections
• Address pedestrian, bicycle and transit
access, circulation and crossings
• Accommodate regional traffic without
adversely impacting local conditions
• Allow for a local network to support future
development and abutting neighborhoods
2035 Future Traffic Volumes
2035 Regional Model (CTPS)
Local Development Parcels (City)
2035 No Build Traffic Volumes
2035 Future Growth Summary
Vehicular Volumes:
Casey Overpass (Regional):
+ 5%
Surface Roads (Regional & Local): + 12%
Non-Motorized (Peds & Bikes):
+ 13%
Transit Ridership:
+ 10%
How the Analysis was Performed
1.
2.
3.
Base Year Calibrated – 2010
Forecast Year Future – 2035
Alternatives developed – CTPS performed regional
analysis
•
•
•
4.
5.
Overall volumes
Travel times
Air Quality
Regional analysis results provided to project team
Project team examined local traffic operations
Traffic Calming
Traffic Calming Treatments
Design is ongoing
1.
2.
3.
Landscaping
Crosswalk Treatments
Signal Spacing
Level of Service &
Queue Analysis Results
Existing Traffic Operations
• Most of the study area intersections
operate at overall Level of Service (LOS)
“E;” with specific movements at LOS “F”
• Queues exceed existing storage space
Future No-Build Traffic Operations
• LOS and delay decline over existing conditions
• One intersection operates at overall LOS “F”
• Queues exceed current storage space
Future Build Traffic Operations
• Vehicular LOS improves at study area intersections;
most at LOS “D” or better.
• Queues are managed between intersections
• Analysis included both North-South and East-West
corridors
• Pedestrian and Bicycle operations at LOS “C” or
better.
• Surface streets are organized into conventional
intersections; the missing East-West link is provided
Regional Analysis
Central Transportation Planning
Staff Analysis
CTPS Regional Traffic Model
• Model runs for At-Grade and Bridge
Alternatives
• Initial results show no significant changes to:
• Traffic Volumes
• Vehicle Miles Traveled (VMT)
• Vehicle Hours Traveled (VHT)
• Air Quality/Emissions
CTPS Key Findings
• Both build scenarios allow
the same magnitude of
traffic to move through
this area
• Both build scenarios cater
to the same markets
• Both build scenarios result
in similar travel times for
trips
Detailed LOS and Queue Analyses
• Traffic Operations Improved for both
alternatives over existing conditions (see
Technical Memoranda)
• Acceptable traffic operations provided for
both alternatives
• Queues managed within available
storage area
• Operations comparable for at-grade and
bridge alternatives
Travel Time Comparison
• Travel times for existing based on
current volumes and presented for
comparison only
• Travel times for alternatives based
on 2035 volumes and analysis
• Travel times are for peak hours
Peak Hour Travel Time Results
• Both alternatives improve overall travel times within
the project limits
• Overall travel times for the alternatives are
comparable
• At-grade improves travel time for many moves,
particularly north-south
• At-grade increases travel time for affected left-turns
and east-west regional traffic (30-90 seconds)
• Regional delays offset local travel time increases
Future Operations with Modified
Lane Configurations
Design is ongoing
Further Discussed at DAG #3: Mobility (6-18-12)
1. Pros and Cons of different lane
configurations
2. Queues and signalization
3. Right sizing roadway 2016 versus 2035
Right-Turn Treatments
Design is ongoing
Further Discussed at DAG #3: Mobility (6-18-12)
1.
2.
3.
Pros and Cons of channelized right turns
Right-Turn-on-Red
Pedestrian Signal Timing
Traffic Operations
Future Traffic Conditions: Summary
• Pedestrian/Bike/Transit Operations
Improved
• Overall Vehicle Capacity Increased
• No Added or Diverted Traffic
• Overall Travel Times Remain Constant
East West
Regional Travel
• Regional travel times relatively unchanged for
overall trip
• Any in-bound delays at grade on New Washington
are offset by existing delays at Murray Circle
• In fact, the new design of New Washington may
“meter” the travel times, providing more
systematic processing of traffic
Bar chart of traffic by time of day
Discussion
Pedestrian Crossings
Pedestrian Crossings
Design is ongoing
Will be further examined in DAG #3: Mobility
1.
Ongoing efforts to minimize the pedestrian
crossing distance
2.
Location of pedestrians within the cross-section
3.
Pedestrian Signal Timing – length of walk phase,
exclusive versus concurrent phasing
Transit Accommodations
Transit Signalization
1.
Bus Signal
Phases
2.
“7th lane”
3.
Deadhead
Buses
School Bus Coordination
• Met with Boston’s
School
Department BusOperations on
5-15-12
• Meeting with
METCO bus
service on 5-25-12
Ongoing MBTA
Coordination
•Compiling data on bus
volumes by peak hour,
including deadhead buses
•Coordination on bus priorities
Emergency Response
Time
Emergency Response Times
•
Future Build Condition = Faster Emergency
Response Times
•
Construction
Design is ongoing
More at Construction Management DAG
Meeting (7-18-12)
Alternative Routes
Alternative Routes
•
Future Build Condition = Traffic Diversions are not
anticipated
•
Construction
Design is ongoing
More at Construction Management DAG
Meeting (7-18-12)
Local Diversions (cut-through)
• Concerns on cut through
focused on east/west travel.
• The At-Grade Alternative
increases east/west travel by
only 30 to 90 seconds.
• The travel times along
alternate routes (potential cutthrough routes) are greater
than the proposed at-grade
network.
For more Information:
Project Web Site
For Detailed Results
Casey Project Web Site Documents
http://www.massdot.state.ma.us/caseyoverpass/
Traffic
Documents
• Traffic flow maps
by mode
• Level of Service by
Mode
• CTPS graphics
• Travel Time
Analysis
Meetings
• Notices
• Presentations
• Graphics
• Minutes
Previous Traffic Discussions
Discussed at 11 WAG & 5 Public Meetings
Primary Traffic meetings included:
• Public Meeting #1 – 4/6/11
• WAG 2B – 5/4/11
• WAG 3B – 6/14/11
• WAG 5A – 9/28/11
• WAG 5B – 10/25/11
• Public Meeting #5 – 11/21/11
Updates Post Planning Phase
Traffic Peer Review
Conducted by CDM Smith
Dec. ‟11–Jan „12
“Summary:
• …, the traffic analysis provided for the Casey overpass
Project has been performed in a professional manner
consistent with standard traffic engineering practices and
the guidelines of the MassDOT 2006 Project Development
and Design Guidebook.
• …traffic operations will be more efficient in the future year
with either alternative than the existing conditions or no
build conditions.”
Additional Review conducted
By notable traffic advocates
“Report on Evaluation of Two Design
Options for Casey Overpass”
Volume Graphics Updates
• Traffic count data for Cemetery Road
• Bus left-turn volumes
• Minor graphic clarifications
• Adjusted volumes at Orchardhill Road
Ongoing/Future Traffic
Analysis Summary
A Look Ahead
Signal Coordination
Coordinated Signal Systems:
•Casey Arborway (E-W)
•Washington Street (N-S)
•Hyde Park Avenue (N-S)
Parking Supply
On and Off-Street
Existing Parking Supply
Proposed Parking Supply
Parking Changes
Parking changes
were reflected in
the future traffic
volumes
–(i.e. -LAZ
parking lot)
Next Steps:
DAG #3: Mobility Topics
DAG #3 Mobility Topics:
•Off-Peak Design Options
•Build Year LOS, queues, delays
•Turn Treatments
•Signal Details
•Bus Operations
•Cut-Thru Traffic
Casey Arborway Project
Discussion
End of Presentation
Extra Slides
Conceptual Alternatives
TRAFFIC
Traffic Simulations
Bridge Alternative
At-Grade Alternative
How can traffic operations be similar?
• North-south traffic volumes unchanged between
alternatives
• At-grade offers additional improvements to critical northsouth link on South Street
• Removal of Bridge only adds east-west through traffic to
surface streets (additional thru lanes provided at-grade)
• All turning movements happen at grade regardless
At-Grade Conceptual Alternative
DESIGNER GENERAL’S WARNING: THE DESIGN SHOWN
HERE IS PRELIMINARY AND CONCEPTUAL, DESPITE THE
HARD LINE FINISHED STYLE RESULTING FROM THE
SOFTWARE PROGRAMS USED
Bridge Conceptual Alternative
DESIGNER GENERAL’S WARNING: THE DESIGN SHOWN
HERE IS PRELIMINARY AND CONCEPTUAL, DESPITE THE
HARD LINE FINISHED STYLE RESULTING FROM THE
SOFTWARE PROGRAMS USED