Post on 20-Mar-2017
County of Fairfax, Virginia
Reston Network Analysis2050 Unmitigated Results
January 11, 2016
Kristin CalkinsFairfax County Department of Transportation
County of Fairfax, Virginia
Agenda
• Study Purpose• Project Progress Overview• Methodology• 2050 Unmitigated Modeling Results• Mitigation Options• Next Steps• Questions and Answers2
County of Fairfax, Virginia
Purpose of Study• Conduct a detailed analysis of the grid of streets
to determine:– Number of lanes between and at intersections– How to best serve pedestrians, bikes and transit– Right-of-way needs
• Assign urban street types and modal emphasis based on Department of Rail and Public Transportation Multimodal System Design Guidelines
• Conduct a phasing analysis of when larger projects are needed
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County of Fairfax, Virginia
Reston Network Analysis Tasks1. Data Collection – done2. Existing Conditions – done3. Future Conditions – 2050 unmitigated underway
– Determine Grid of Streets
4. Phasing Analysis 5. DRPT Classifications6. Specific location improvements for additional study
– Reston Parkway– Sunrise Valley Drive @ Fairfax County Parkway– Spring Street @ Fairfax County Parkway– Rock Hill Bridge
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Data Collection• Traffic
Counts in June 2015
• Travel Time Runs
Existing Conditions• Capacity
Analysis • Level of
Service
Test Grid of Streets (2030 & 2050)• Traffic
Forecasting Capacity Analysis
• Level of Service
Mitigation• Signal re-
timing• New links• Turn lanes• Additional
lanes
Roadway Classification• DRPT Design
Guidelines• Bike lanes• Sidewalks/
Pedestrian routes
• On-Street Parking
• Transit Routes
Finalize Grid of Streets (2030 & 2050) Based on:• Advisory
Group input• Stakeholder
input• Community
input
Phasing Analysis• Prioritizatio
n of larger projects
Network Analysis Project Process
Advisory Group input, Stakeholder input, Community input
County of Fairfax, Virginia
Project Progress Overview • Completed data collection• Finalized existing conditions • Begun analyzing future conditions (2030
& 2050)– Developed ITE-based vehicle trips for 2030 and 2050
• Significant vehicle trip reductions due to transit, TDM, and bike and pedestrian increases associated with the Metro station and TOD development
– Developed the 2050 VISUM model – Completed 2050 VISUM preliminary vehicle trip
assignment without mitigation6
County of Fairfax, Virginia
Methodology• County model
– Seed trip tables– Roadway network
• VISUM– Model development including local roads & driveways
• VISUM model input– Origin/Destination (O-D) trip tables from County and Regional Model– ITE-based trips– SYNCHRO for signal timing optimization
• VISUM model output– Intersection delay and level of service– Link volumes– Turning movements volumes and LOS
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County of Fairfax, Virginia
Reston VISUM Model
Tysons
Reston
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County of Fairfax, Virginia
2050 UnmitigatedVISUM Modeling Results
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County of Fairfax, Virginia
2050 Unmitigated Results• Stop controlled intersections:
– Overall LOS– Overall Delay
• Signalized intersections:– Overall LOS– Overall Delay– LOS by movement– Delay by movement– Volumes for each movement
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County of Fairfax, Virginia
LOS Results• Of 42 key signalized intersections in the study area,
in 2050 unmitigated the following operate at Level of Service F:– AM peak hour: 24– PM peak hour: 26– AM and PM peak hours: 22
• Existing development is 31,812,244 square feet• 2050 development is approximately 100,000,000
square feet (including Innovation TSA)
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County of Fairfax, Virginia
Existing Peak Hour LOS (Page 1)
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County of Fairfax, Virginia
2050 Unmitigated Peak Hour LOS (Page 1)
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County of Fairfax, Virginia
Existing Peak Hour LOS (Page 2)
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County of Fairfax, Virginia
2050 Unmitigated Peak Hour LOS (Page 2)
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County of Fairfax, Virginia
Existing Peak Hour LOS (Page 3)
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County of Fairfax, Virginia
2050 Unmitigated Peak Hour LOS (Page 3)
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County of Fairfax, Virginia
LOS Results
• Intersections with delay of 120 seconds or more– AM peak hour: 17– PM peak hour: 19– AM and PM peak hours: 14
• LOS E is the standard for the Reston Transit Station Areas
Delay (s/veh)
LOSSignalized
IntersectionsUnsignalized Intersections
A ≤ 10 ≤ 10
B > 10 - 20 10 - 15
C > 20 - 35 15 - 25
D > 35 - 55 25 - 35
E > 55 - 80 35 - 50
F > 80 ≥50
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County of Fairfax, Virginia
2050 Unmitigated Problem Locations
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County of Fairfax, Virginia
2050 Unmitigated Problem Locations (cont.)
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County of Fairfax, Virginia
2050 Unmitigated Problem Locations (cont.)
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County of Fairfax, Virginia
2050 Unmitigated Problem Locations (cont.)
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• Intersections with Delay over 120 Seconds1. Frying Pan Road & Sunrise Valley Drive2. Frying Pan Road & Centreville Road3. Centreville Road & Sunrise Valley Drive4. Centreville Road & the Eastbound DTR Ramps5. Centreville Road & the Westbound DTR Ramps (PM only)6. Monroe Street & Fox Mill Road (AM only)7. Monroe Street & Sunrise Valley Drive (PM only)8. Spring Street & Herndon Parkway9. Fairfax County Parkway & Sunrise Valley Drive10. Fairfax County Parkway & New Dominion (PM only)11. Fairfax County Parkway & Baron Cameron Avenue
County of Fairfax, Virginia
2050 Unmitigated Problem Locations (cont.)
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• Intersections with Delay over 120 Seconds12. Town Center Parkway & Baron Cameron Avenue 13. Town Center Parkway & Sunset Hills Road14. Reston Parkway & Baron Cameron Avenue15. Reston Parkway & Sunset Hills Road16. Reston Parkway & Sunrise Valley Drive 17. Reston Parkway & South Lakes Drive18. Sunrise Valley Drive & Soapstone Drive (PM only)19. Wiehle Avenue & Eastbound DTR Ramps (AM only)20. Hunter Mill Road & Sunrise Valley Drive (AM only)21. Hunter Mill Road & Westbound DTR Ramps 22. Hunter Mill Road & Sunset Hills Road (PM only)
County of Fairfax, Virginia
2050 Unmitigated Data• Stop controlled intersections:
– Overall LOS– Overall Delay
• Signalized intersections:– Overall LOS– Overall Delay– LOS by movement– Delay by movement– Volumes for each movement
• Link volumes• Driveway volumes
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County of Fairfax, Virginia
2050 AM Peak Hour Data
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County of Fairfax, Virginia
PM 2050 Peak Hour Data
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County of Fairfax, Virginia
2050 AM Peak Hour Data
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County of Fairfax, Virginia
2050 PM Peak Hour Data
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County of Fairfax, Virginia
AM Peak Hour Site Trips and Link Volumes
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County of Fairfax, Virginia
PM Peak Hour Site Trips and Link Volumes
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County of Fairfax, Virginia
Existing Reston TSA Walk-shed
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County of Fairfax, Virginia
2050 Reston TSA Walk-shed
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County of Fairfax, Virginia
2050 Walkshed
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Distance Existing With Grid Increase0-.25 mile 0.06 0.10 66%
.25 - 0.5 mile 0.22 0.46 108%.05-1.0 mile 1.86 2.52 35%
Total 2.15 3.09 44%
Walkshed Area (square mile)
County of Fairfax, Virginia
Mitigation• Mitigation reduces vehicle congestion • Mitigation reduced delays experienced at
intersections• Mitigation improves the reliability of travel times
through an area (for both buses and vehicles)
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County of Fairfax, Virginia
Mitigation Options• Mitigation Measures - Tiered Approach
– No right of way impact – Some right of way impact– Large scale mitigations if needed
– Consultation with Advisory Group and Stakeholders
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County of Fairfax, Virginia
Mitigation MeasuresNo Right of Way Impact
•No/Low Cost: Intersection Reconfiguration– Optimized signal timing and phasing– Lane configuration modification
Westwood Center Dr. @ Route 7 (2013)
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Westwood Center Dr. @ Route 7 (2015)
County of Fairfax, Virginia
Mitigation Measures (cont.)No Right of Way Impact
•Existing and Potential Future Signals– Adding/removing traffic signals– Adding/modifying stop control
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Westwood Center Dr. @ Sheraton Tysons Dr. (2013)
Westwood Center Dr. @ Sheraton Tysons Dr. (2015)
County of Fairfax, Virginia
Mitigation MeasuresSome Right of Way Impact
• Turn lanes– Left and Right turn lanes– Add storage– Reduces queuing on to through movement
• Additional through lane• Additional grid link
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County of Fairfax, Virginia
Mitigation MeasuresAlternative Intersection Treatment
• Median U-Turn/Superstreet– Eliminate left turn movement for side streets– Increases thru movement green time– Additional needed ROW to provide turn radius
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County of Fairfax, Virginia
Mitigation MeasuresLarge Mitigation Measures
• Underpass/Overpass– Provides for an uninterrupted thru movement
• Only done in close coordination with Advisory Group and Stakeholders after all other mitigation measures have not worked
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County of Fairfax, Virginia
Next Steps• Apply no ROW impact Mitigation Measures
– Modifications to the lane configuration– Signal timing and phasing optimization – All-way stop vs. two-way stop evaluation – Additional traffic signals
• Meet with Stakeholder Group on no ROW impact Mitigation Measure LOS Results
• Develop possible mitigation measures for problem locations that remain to discuss with Advisory Group
• Meet with Advisory Group on possible some-ROW impact mitigation measures
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County of Fairfax, Virginia
ScheduleTask Description
1A Land Use and Networks - Task is Complete
1B Traffic Counts - Task is Complete
2A Establish Existing Conditions - Task is Complete
2B Calibrate Against Existing Conditions - Task is Complete
3A2 Analyze Future Conditions (2050)
3A1 Analyze Future Conditions (2030)
3B Simulation of the Dulles Toll Road
3C Microsimulation - Optional
4A Meetings/Presentations
5A Phasing Analysis - Existing Conditions
5B Phasing Analysis - 2050 - Optional
6 Determination of DRPT Guidelines Roadway Classification
7 Documentation
8 Reston Parkway Capacity Improvements
9 Fairfax County Parkway & Spring Street Interchange
10 Fairfax County Parkway & Sunrise Valley Drive
11 Rock Hill Bridge at Sunrise Valley Drive
12A Meetings/Presentations
Feb-15May-15 Jun-15 Jul-15 Aug-15 Sep-15 Oct-15 Nov-15 Dec-15 Jan-16 Sep-16 Oct-16Mar-16 Apr-16 May-16 Jun-16 Jul-16 Aug-16
1/11/16
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County of Fairfax, Virginia
Questions & Comments
For questions and comments about the study please contact:
Kristin Calkins: Kristin.Calkins@fairfaxcounty.gov(703) 877-5710
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