1. County of Fairfax, Virginia
Reston Network Analysis
2050 1st Tier Mitigation Results
February 19, 2016
Stakeholders Group
Kristin Calkins
Fairfax County Department of Transportation
2. County of Fairfax, Virginia
Agenda
• Study Purpose
• Project Progress Overview
• 2050 1st Tier Mitigation Results
• Mitigation Options
• Next Steps
• Questions and Answers
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3. 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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4. County of Fairfax, Virginia
Reston Network Analysis Tasks
1. Data Collection – done
2. Existing Conditions – done
3. Future Conditions – 2050 mitigation underway
– Determine Grid of Streets
4. Phasing Analysis
5. DRPT Classifications
6. 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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5. 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
• Prioritization
of larger
projects
Network Analysis Project Process
Advisory Group input, Stakeholder input, Community input
8. County of Fairfax, Virginia
Purpose of Mitigation
• Mitigation reduces vehicle congestion
• Mitigation reduces delays experienced at
intersections
• Mitigation improves the reliability of travel times
through an area (for both buses and vehicles)
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9. County of Fairfax, Virginia
Mitigation Options
• Mitigation Measures - Tiered Approach
– 1st Tier: No right of way (ROW) impact
– 2nd Tier: Some right of way impact
– 3rd Tier: Large scale mitigations if needed
– Consultation with Advisory Group and
Stakeholders
• Each grid link is initially assumed to be one
lane in each direction
– No turn lanes at new intersections
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10. County of Fairfax, Virginia
2050 1st Tier Mitigation Measures
• No ROW Impact Mitigation Measures
– Modifications to lane configurations
– Signal timing and phasing optimization
– All-way stop vs. two-way stop evaluation
– Additional traffic signals
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11. County of Fairfax, Virginia
Mitigation Measures
1st Tier: No Right of Way Impact
•Intersection Reconfiguration
– Optimized signal timing and phasing
– Lane configuration modification
Westwood Center Dr. @ Route 7 (2013) Westwood Center Dr. @ Route 7 (2015)
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12. County of Fairfax, Virginia
Mitigation Measures (Cont.)
1st Tier: No Right of Way Impact
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•Existing and Potential Future Signals
– Adding/removing traffic signals
– Adding/modifying stop control
– Modifying Parking
Westwood Center Dr. @
Sheraton Tysons Dr. (2015)
Westwood Center Dr. @
Sheraton Tysons Dr. (2013)
14. County of Fairfax, Virginia
2050 1st Tier Intersection Control
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Existing Signal
Signal Proposed by
different study
Signal Proposed
15. County of Fairfax, Virginia
2050 1st Tier Intersection Control (Cont.)
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Existing Signal
Signal Proposed by
different study
Signal Proposed
16. County of Fairfax, Virginia
2050 1st Tier Signal Recommendations
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New Signalized Intersection Locations
Sunrise Valley Dr. @ Wood Oak Dr. Sunrise Valley Dr. @ Commerce Park Dr. East
Sunrise Valley Dr. @ Colts Brook Dr. Soapstone Overpass @ Indian Ridge Rd. Extension
Frying Pan Rd. @ Greg Roy Ln. Sunset Hills Rd. @ West of Town Center Pkwy.
Monroe St. @ Future Connection to Herndon Metro Town Center Pkwy. @ North of Sunset Hills
Glade Dr. @ Pinecrest Rd. Town Center Pkwy. @ Market St.
South Lakes Dr. @ Pinecrest Rd. Sunset Hills Rd. @ Library St.
Sunrise Valley Dr. @ Pinecrest Rd. Extended Sunset Hills Rd. @ Soapstone Overpass
Sunrise Valley Dr. @ Town Center Pkwy. Sunset Hills Rd. @ East of Soapstone Overpass
Town Center Pkwy. @ North of Sunrise Valley Dr. Sunset Hills Rd. @ South Lakes Overpass
West of Reston Pkwy. with grid street Reston Station Blvd. @ Metro Center Dr.
Sunrise Valley Dr. @ Roland Clarke Place Reston Station Blvd. @ Michael Faraday Dr.
Sunrise Valley Dr. @ Indian Ridge Rd. Isaac Newton Square S. @ Isaac Newton Square W.
Sunrise Valley Dr. @ Commerce Park Dr. West Wiehle Ave. @ Isaac Newton Square N.
17. County of Fairfax, Virginia
Lane Re-allocation
Sunrise Valley Drive @ Preston White Drive / S Lake Drive
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2050 Unmitigated 2050 1st Tier Mitigation
19. County of Fairfax, Virginia
2050 1st Tier Mitigation 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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20. County of Fairfax, Virginia
1st Tier LOS Results
• LOS E is the standard for the Reston Transit
Station Areas
• Of 42 key signalized intersections in the study area,
the following are forecast operate at Level of
Service F:
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42 Key Intersections – LOS F
2050 Unmitigated 2050 1st Tier
AM Peak Hour 24 11
PM Peak Hour 26 11
AM & PM Peak Hour 22 9
27. County of Fairfax, Virginia
2050 Problem Locations
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Intersections – 120+ Seconds of Delay
Peak Hour
2050
Unmitigated
2050 1st Tier
Mitigation
AM 17 12
PM 19 7
AM & PM 14 5
With signal re-timings and the introduction
of signals there has been a reduction in the
number of intersections experiencing delays
in excess of 120 seconds
34. County of Fairfax, Virginia
2050 1st Tier Problem Locations
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• 2050 Unmitigated had 22 Problem Locations
• Intersections with Delay over 120 Seconds
1. Frying Pan Road & Sunrise Valley Drive
2. Frying Pan Road & Centreville Road
3. Centreville Road & Coppermine Road
4. Centreville Road & Sunrise Valley Drive
5. Monroe Street & Fox Mill Road
6. Spring Street & Herndon Parkway
7. Fairfax County Parkway & Baron Cameron Avenue
8. Fairfax County Parkway & Sunrise Valley Drive
9. Town Center Parkway & Sunset Hills Road
10. Reston Parkway & Baron Cameron Avenue
11. Reston Parkway & Bowman Towne Drive
12. Reston Parkway & Sunrise Valley Drive
13. Reston Parkway & South Lakes Drive
45. County of Fairfax, Virginia
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Mitigation Measures
2nd Tier: Some Right of Way Impact
• Turn lanes
– New Left and Right turn lanes
– Extended turn lanes: adds storage
• Additional through lane
• Additional grid link
46. County of Fairfax, Virginia
Mitigation Measures
3rd Tier: Alternative Intersection Treatment
• Median U-Turn/Superstreet
– Eliminates left turn movement for side streets
– Increases thru movement green time
– Additional needed ROW to provide turn radius
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47. County of Fairfax, Virginia
Mitigation Measures
3rd Tier: Large 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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48. County of Fairfax, Virginia
Next Steps
• Apply ROW impact Mitigation Measures
– Turn lanes
– Turn lane extensions
– Additional thru lane
• Develop possible mitigation measures for problem
locations that remain to discuss with Advisory Group
• Meet with Advisory Group on possible 2nd Tier
mitigation measures
• Meet with Stakeholder group on 2nd Tier
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49. County of Fairfax, Virginia
Schedule
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Task 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
2/19/16
50. County of Fairfax, Virginia
Questions & Comments
For questions and comments about the study please
contact:
Kristin Calkins: Kristin.Calkins@fairfaxcounty.gov
(703) 877-5710
http://www.fairfaxcounty.gov/fcdot/restonnetworkanalysis/
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