Date post: | 12-Sep-2014 |
Category: |
Business |
View: | 7 times |
Download: | 0 times |
HRMPO Proposed Alternatives1. 3rd Crossing from Southside to the Northern Peninsula.
a. Phase 1: Widen I-664 from Bowers Hill to Hampton.b. Phase 2: Add a bridge-tunnel between the existing MMMBT and
I-564 in Norfolk and a connector across Craney Island from new bridge-tunnel and the Western Freeway.
2. Southeastern Parkway/Dominion Boulevard from Virginia Beach to Chesapeake.
3. Widen Midtown Tunnel and extend MLK Freeway to I-264.
4. Improving Route 460 (eventual construction of a parallel roadway)
5. Widen I-64 on the Northern Peninsula as far west as Route 199.
6. Widen I-64 on the Southside (including the High Rise Bridge) from Battlefield Boulevard in Chesapeake to Bowers Hill in Suffolk
HRMPO Proposed Alternatives
Key Sections of StudyMacroscopic transportation model (regional traffic demand model)
Freight Modeling Adds impact of cargo transfer and large trucks to the
traffic demand model
Congestion analysis Mesoscopic transportation simulation Ability of selected sections of network assessed for ability
to clear congestion
Accidents and Incidents
Potential economic model
Assistance Provided StudyVirginia Department of Transportation Statewide traffic demand model Hampton Roads regional traffic demand model Global Insight, Inc. Transearch Database (nationwide
database of freight traffic flow) Accident and incident data compiled by Virginia State
Police (restricted to events with injury or property damage exceeding $1000)
Hampton Roads Traffic Operations Center Hampton Roads accident and incident data based on
Safety Service Patrols reportsHampton Roads Metropolitan Planning Organization Hourly traffic flow data for 2006 Analysis suggestions, reviews, and comments
Metrics Used in AnalysisVehicle Volume: The number of vehicles assigned to the analyzed road section.
Level of Service Indicator (Volume/Capacity): Road segment volume is the maximum demand (number of vehicles) using the segment. Capacity is the maximum that can be handled before additional traffic is diverted to other routes. V/C = 1 means a road is operating at its maximum capability. V/C>1 means congestion will occur due to high volume.
Speed Decay: Free-flow speed (FFS) is the vehicle speed for vehicles experiencing no congestion. Congestion forces vehicles to slow. Speed decay is the ratio of free-flow speed to modeled speed. Speed decay values of >1.0 indicate speeds are reduced due to congestion.
Freight Traffic Modeling
Integrates freight traffic with passenger traffic in the traffic demand model.
Commonwealth does not have a Cube Cargo freight model.
Commonwealth provided the Global Insight Transearch Database, which was used to extract anticipated 2030 truck volumes.
Freight Modeling Metrics
Four metrics have been selected to describe the performance of the road transportation system. Truck volume Total vehicle volume Level of service (volume/Capacity) Speed decay (Free-flow to congested speed ratio)
Tables summarizing these performance indicators for 27 selected locations in the road network are provided for each scenario
Year 2000 Level of Service
Significant sections around region are already congested or extremely congested
2030 No-build Level of Service
Majority of principal roads throughout region are congested or extremely congested
Year 2030 All Build Level of Service
Congestion improves compared to no-build scenario, especially on MMMBT and JRB.
3rd Crossing (Ph. 2) Level of Service
Significant improvement at MMMBT and some improvement to HRBT with new lanes on I-664 .
Six-lane HRBT Level of Service
Improved service on JRB and MMMBT as traffic shifts to expanded HRBT, which remains highly congested with increased volume.
Year 2000 Speed Decay
Lower than free flow speeds in large portions of Peninsula, Virginia Beach, Chesapeake and all bridges and tunnels
Year 2030 No-build Speed Decay
Severe speed reductions much more extensive on highways and on selected local roads.
Year 2030 All Build Speed Decay
Compared to no-build scenario, vehicle movements will be faster, but roads remain congested.
3rd Crossing (Ph. 2) Speed Decay
I-664 is less congested, but congestion on other roads remains
Six Lane HRBT Speed Decay
Widespread low congested speeds remain, but are improved on HRBT, MMBT, and JRB
Macroscopic Modeling“Big Picture” Cannot model individual vehicles All vehicles modeled as passenger cars
Assesses over 5 million trips/day and over 1000 origin and destination zonesFourteen total scenarios analyzedAll alternatives assumed to be assigned tolls with rates as indicated in the VDOT provided modelCube Voyager (Citilabs®, Inc.)
Scenarios Analyzed
Fourteen total Scenarios
Four main sections No build scenario All build scenario (includes completion of
the six alternatives proposed by the HRMPO)
Individual alternatives analyses HRBT analyses
HRBT Traffic Demand and V/C
Peak Hour V/C Ratios of Road Segments Where Each Project is Built
0 0.5 1 1.5 2 2.5
Build
No Build
I-64 Widening (Peninsula Only)
0 0.5 1 1.5 2 2.5
Build
No Build
I-64 Widening (Southside Only)
0 0.5 1 1.5 2 2.5
Build
No Build
Third Crossing-Phase 1
0 0.5 1 1.5 2 2.5
Build
No Build
Third Crossing-Phase 2
0 0.5 1 1.5 2 2.5
Build
No Build
US 460 Only
0 0.5 1 1.5 2 2.5
Build
No Build
Midtown Tunnel
Peak Hour V/C Ratios: Impacts of “All Build” and HRBT Expansion on Third Crossing and
Midtown Tunnel
0 0.5 1 1.5 2 2.5
All Build + HRBT 6 Lanes
All Build (HRBT 4 Lanes)
Build
No Build
Third Crossing-Phase 1
0 0.5 1 1.5 2 2.5
All Build + HRBT 6 Lanes
All Build (HRBT 4 Lanes)
Build
No Build
Third Crossing-Phase 2
0 0.5 1 1.5 2 2.5
All Build + HRBT 6 Lanes
All Build (HRBT 4 Lanes)
Build
No Build
Midtown Tunnel
Peak Hour Speeds (mph) on Road Segments Where Each Project is Built
0 10 20 30 40 50 60
Build
No Build
Third Crossing-Phase 1
0 10 20 30 40 50 60
Build
No Build
I-64 Widening (Peninsula Only)
0 10 20 30 40 50 60
Build
No Build
Third Crossing-Phase 2
0 10 20 30 40 50 60
Build
No Build
I-64 Widening (Southside Only)
0 10 20 30 40 50 60
Build
No Build
Midtown Tunnel
0 10 20 30 40 50 60
Build
No Build
US 460 Only
Incident-Induced Congestion Analysis
Mesoscopic simulation: Citilabs® Cube Avenue
Selected sections of network tested
Testing assumed rush hour conditions and three incident scenarios: Shoulder blocked One lane blocked Two lanes blocked (selected sections)
For simplicity of comparison, all incidents assumed to have 15 minute duration
Incident-Reduced Capacity
Values taken from HCM 2000 Exhibit 28-6
Critical Segment Daily Traffic Flow
Note variances in flow during the day and variances between segments
Rush hour volumes simulated during incident
Congestion Analysis Results
Congestion Analysis Videos
Video Simulation Unavailableat this time
[email protected] more information
Congestion Analysis Videos
Simulations Videos show:
A 15-minute incident at HRBT and its effects on length of back-up, traffic flow and time to clear traffic as follows:
1.Current status2.Status with 1 additional HRBT lane both east and west3.Status with “3rd crossing” diverting traffic through MMBT
Study ConclusionsFailure to take action should not be an option. All major road ways will be very congested. Peak hour demand will exceed capacity by more than 50% on most
critical roads.
All alternatives significantly improve local recurrent and incident induced congestion.Of 6 proposed alternatives, only the 3rd Crossing appreciably improves conditions at the HRBT. Even with the building of the 3rd Crossing and a significant shift of traffic
to this route, volume at the HRBT will still exceed capacity.
Only expanding the HRBT can relieve both recurrent and incident-induced congestion at the HRBT. Expanding the HRBT to 6 lanes (or more) and imposition of tolls will
relieve some, but not all, of the recurrent congestion. Combining an expanded HRBT and the 3rd Crossing (Phase 2) greatly
improves congestion.
Questions?
Backup Slides
HRBT Traffic Demand and V/C
p. B-7
Project Traffic Demand, V/C, and Speed
p. B-11