Reston Network Analysis: Existing Phasing Analysis and 2050 Tier 3

1. County of Fairfax, Virginia
Reston Network Analysis
Existing Phasing Analysis & 2050 Tier 3
August 8 & 10, 2016
Advisory Group & Stakeholders Meeting
Kristin Calkins
Fairfax County Department of Transportation

2. 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
2

3. 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

4. County of Fairfax, Virginia
Phasing Analysis
Existing Conditions
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5. County of Fairfax, Virginia
Existing Conditions Phasing Analysis
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• This process will help the prioritize roadway
improvements in the Reston TSAs
• Based on greatest improvement in
congestion compared the network without the
project
• When Tier 3 is finalized a 2050 phasing
analysis will be completed to determine long
term importance

6. County of Fairfax, Virginia
Existing Conditions Phasing Analysis
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Reston Phasing Analysis Projects
Grid of Streets
DTR Crossing at Soapstone Overpass – Sunrise Valley Dr to Sunset Hills Rd
DTR Town Center Parkway Underpass – Sunrise Valley Dr to Sunset Hills Rd
Fox Mill Road Widening – Reston Parkway to Monroe Street
Monroe Street Widening – West Ox Road to Town of Herndon
Pinecrest Road Extension – South Lakes Dr to Sunrise Valley Dr
Reston Parkway Widening – South Lakes Drive to DTR
Fairfax County Parkway - DTR to West Ox HOV
Fairfax County Parkway at Sunrise Valley Drive (Interchange)
South Lakes Drive Overpass – Sunrise Valley Drive to Sunset Hills Rd
West Ox Road Widening – Lawyers Road to Centreville Road
Sunset Hills Road Widening – Fairfax County Parkway to Wiehle (6) and Wiehle to
Hunter Mill Road (4)

7. County of Fairfax, Virginia
Existing Conditions Phasing Analysis
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8. County of Fairfax, Virginia
Phasing Analysis Process
• The base year (2015) VISUM AM and
PM peak hour models were the starting
point for the phasing analysis.
• Each planned improvement was added to
the base year VISUM model.
• Vehicle hours travelled (VHT) were used
to measure traffic congestion and benefit
of each improvement.
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9. County of Fairfax, Virginia
Results – Existing Phasing Analysis
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Improvement Ranking
Hours of Delay w/ Project
vs. Existing Conditions
Grid of Street Grid of Streets 1 -1,216
Town Center Town Center Parkway Underpass 2 -374
Soapstone Soapstone Overpass 3 -300
FCP/HOV Fairfax County Parkway - 6 lanes with High Occupancy Vehicle (HOV) lane(s) 4 -299
Sunset Hills
Widen Sunset Hills Road – 6 lanes from Wiehle Ave to Fairfax County Pkwy, and 4 lanes
from Wiehle Ave to Hunter Mill Road
5 -257
South Lakes South Lakes Overpass 6 -240
FCP/SRV Fairfax County Parkway and Sunrise Valley Drive Interchange 7 -184
Reston Pkwy Widen Reston Parkway - 6 lanes from South Lakes Drive to the DAAR 8 -82
Monroe Widen Monroe Street - 4 lanes from West Ox Road to the Town of Herndon 9 -27
Pinecrest Extend Pinecrest Road from South Lakes Drive to Sunrise Valley Drive 10 -2
Fox Mill Widen Fox Mill Road - 4 lanes from Reston Parkway to Monroe Street 11 0
West Ox Widen West Ox Road - 4 lanes from Lawyers Road to Centreville Road 12 28

10. County of Fairfax, Virginia
Tier 3
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11. County of Fairfax, Virginia
Mitigation Options
• Mitigation Measures - Tiered Approach
– Tier 1: No right of way (ROW) impact
– Tier 2: Some right of way impact
– Tier 3: Large scale mitigations if needed
– Consultation with Advisory Group and
Stakeholders
• Each grid link is initially assumed to be one
lane in each direction (with bike/ped facilities
as specified in the Comprehensive Plan)
– No turn lanes were initially assumed at new
intersections
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12. County of Fairfax, Virginia
2050 2nd Tier Problem Locations
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• Unmitigated had 22 Problem Locations
• After Tier 1: 13 Problem Locations
• After Tier 2: 9 Problem Locations
– 3 are in Innovation TSA which has already been
finalized
– 6 are associated with identified follow-on tasks
• Fairfax County Parkway & Spring Street
• Fairfax County Parkway & Sunrise Valley Drive
• Reston Parkway: From Lawyers Road to Baron Cameron
Ave.

13. County of Fairfax, Virginia
13
2050 2nd Tier Problem Locations

14. County of Fairfax, Virginia
14
Network Analysis Follow-On Tasks
Fairfax County
Pkwy. & Spring St.
Reston Pkwy.
Capacity Improvements
Fairfax County Pkwy.
& Sunrise Valley Dr.

15. County of Fairfax, Virginia
Fairfax County Parkway &
Spring Street
15

16. FCP & Spring Street No Build
Lane Configuration & PM LOS
Intersection
No-build
LOS (PM)
Fairfax County Parkway & Spring Street Ramp B
Spring Street & Fairfax County Parkway Ramp F
Spring Street & Herndon Parkway C
Pros Cons
• Improves conditions on Spring
Street and Herndon Parkway
• Removes slip ramp to southbound
Fairfax County Parkway
16
F
B

17. FCP & Spring Street Option 1: Fairbrook Drive Ramp
Pros Cons
• Maintains existing traffic patterns
• Operating conditions are acceptable
• Geometry for ramp curvature will
need to be investigated
Lane Configuration & PM LOS
Intersection
No-build
LOS (PM)
Option 1
LOS (PM)
Fairfax County Parkway & Spring
Street Ramp
B B
Spring Street & Fairfax County
Parkway Ramp
F D
Spring Street & Herndon Parkway C C
Fairbrook Dr & Fairfax County
Parkway Ramp
- B
17
D
B
B

18. FCP & Spring Street Option 2: Bi-Directional Ramp
Pros Cons
• Eliminates traffic
signal along Fairfax
County Parkway for
improved operating
conditions over no-
build scenario
• Installation of a traffic signal on Spring Street on the
west side of Fairfax County Parkway
• Construction of loop ramp requires large property
takings
• Operating conditions at the new signalized
intersection are at capacity during the AM peak hour.
• Creating a direct connection from the toll road may be
confusing for drivers.
Lane Configuration & PM LOS
Intersection
No-build
LOS (PM)
Option 2
LOS (PM)
Spring Street & Fairfax County
Parkway Ramp
F D
Spring Street & Herndon Parkway C C
Sunset Hills Road & Fairfax
County Parkway NB exit ramp
- D
D
D

19. FCP & Spring Street Option 3: Ramp to NB FCP
Pros Cons
• Eliminates traffic signal along Fairfax
County Parkway for improved operating
conditions over No-build
• Smaller area of impact over loop ramps
• Individual intersections provide for less
delay with all intersections operating at
LOS D or better during the peak hours.
• Installation of a traffic signal on
Spring Street on the west side of
Fairfax County Parkway
• A new weave is created along
Fairfax County Parkway between
the Toll Road and Spring Street.
Lane Configuration & PM LOS
Intersection
No-build
LOS (PM)
Option 3
LOS (PM)
Spring Street & Fairfax County
Parkway Ramp
F C
Spring Street & Herndon Parkway C C
Sunset Hills Road & Fairfax
County Parkway NB exit ramp
- C
C
C

20. County of Fairfax, Virginia
Fairfax County Parkway &
Sunrise Valley Drive
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21. FCP & Sunrise Valley Drive No Build
Intersection
No-build
LOS (PM)
Fairfax County Parkway & Sunrise Valley Drive F
Pros Cons
• Does not require construction or
new right-of-way
• Travelers will experience delays in
excess of 100 seconds
No Build Assumes
Fairfax County Parkway
is Widened to 6 lanes
F

22. FCP & SRVD Option 1: Single Point Urban Interchange (SPUI)
Pros Cons
• Provides improved operating
conditions over No-build
• One signalized intersection
• Queuing does not impact adjacent
intersections
• Large area of impact compared to a
tight diamond for the approach ramps
• Larger crossing distances for
pedestrians
Intersection
No-build
LOS (PM)
Option 1
LOS (PM)
Fairfax County Parkway & Sunrise
Valley Drive
F D
22
D
Fairfax County Parkway Bridge
over Sunrise Valley Drive

23. FCP & SRVD Option 2: Tight Diamond Interchange
Pros Cons
• Provides improved operating
conditions over No-build
• Potentially smaller area of impact
over SPUI
• Queues impact adjacent intersections
• Requires an additional signalized
intersection
• Signal coordination between
intersections can be a concern and
lead to vehicles getting “trapped”
between intersections and creating
additional delay
Intersection
No-build
LOS (PM)
Option 2
LOS (PM)
Fairfax County Parkway & Sunrise
Valley Drive
F -
Fairfax County Parkway (NB) &
Sunrise Valley Drive
- D
Fairfax County Parkway (NB) &
Sunrise Valley Drive
- D
23
D
D
Fairfax County Parkway Bridge
over Sunrise Valley Drive
Graphic is illustrative, intersections would be
constructed closer together

24. County of Fairfax, Virginia
Reston Parkway
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25. County of Fairfax, Virginia
Reston Parkway
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• Option 1: Super Streets
– Restricted left turns at:
• Spectrum Drive
• Bowman Towne/Green Drive
• New Dominion Parkway
• Bluemont Way/Stratford Park Place
• South Lakes Drive
• Glade Drive
• Fox Mill Road
– U-Turns at:
• Between Bowman Towne Drive and Baron Cameron
• Market Street/Stratford House Place
• Sunrise Valley Drive
• Between South Lakes Drive and Glade Drive
• Between Glade Drive and Colts Neck Road
• Colts Neck Road
• Option 2
– Flyover from WB Sunset Hills Road to SB Reston Parkway
– New Road connecting Lawyers Road to Fox Mill Road behind Park &
Ride

26. County of Fairfax, Virginia
Bowman Towne Drive
26
Reston Parkway Alternatives
Stratford House Place
Market Street
Baron Cameron Avenue
No-Build Super Street
New Dominion Parkway
*Pedestrian Signal
Bluemont Way
Sunset Hills Road
WB DTR
EB DTR
Bowman Towne Drive
Stratford House Place
Market Street
Baron Cameron Avenue
Convert to Median U-Turns
Bluemont Way
Sunset Hills Road
WB DTR
EB DTR
Dual WB Left Turns
Median U-Turns
No Left Turns
New Dominion Parkway No Left Turns
No Left Turns
Bowman Towne Drive
Stratford House Place
Market Street
Baron Cameron Avenue
Sunset Fly Over & Lawyers Bypass
New Dominion Parkway
*Pedestrian Signal
Bluemont Way
Sunset Hills Road
WB DTR
EB DTR
Dual WB Left Turns
WB Left Flyover Ramp

27. County of Fairfax, Virginia
Colts Neck Road Colts Neck Road
Fox Mill RoadFox Mill Road
27
Reston Parkway Alternatives (Cont.)
No-Build
WB DTR
EB DTR
Sunrise Valley Drive
Right In/Right Out
South Lakes Drive
Glade Drive
Lawyers Road
WB DTR
EB DTR
Right In/Right Out
No Left Turns
Sunrise Valley Drive
South Lakes Drive
Glade Drive
Lawyers Road
NB U-Turn
No NB/SB Left Turns
Median U-Turns
Median U-Turns
U-Turns
No NB Lefts
Colts Neck Road
Fox Mill Road
WB DTR
EB DTR
Sunrise Valley Drive
Right In/Right Out
South Lakes Drive
Glade Drive
No NB Lefts
Super Street Sunset Fly Over & Lawyers Bypass

28. County of Fairfax, Virginia
Bowman Towne Drive
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Reston Parkway LOS Results
Stratford House Place
Market Street
Baron Cameron Avenue
No-Build
New Dominion Parkway
*Pedestrian Signal
Bluemont Way
Sunset Hills Road
WB DTR
EB DTR
Bowman Towne Drive
Stratford House Place
Market Street
Baron Cameron Avenue
Median U-Turns
Bluemont Way
Sunset Hills Road
WB DTR
EB DTR
Dual WB Left Turns
Median U-Turns
No Left Turns
New Dominion Parkway No Left Turns
No Left Turns
Bowman Towne Drive
Stratford House Place
Market Street
Baron Cameron Avenue
New Dominion Parkway
*Pedestrian Signal
Bluemont Way
Sunset Hills Road
WB DTR
EB DTR
Dual WB Left Turns
WB Left Flyover Ramp
96 Seconds 66 Seconds 66 Seconds
16 Seconds 26 Seconds 16 Seconds
38 Seconds 19 Seconds 38 Seconds
2 Seconds 32 Seconds 2 Seconds
62 Seconds 34 Seconds 62 Seconds
85 Seconds 106 Seconds 57 Seconds
36 Seconds 48 Seconds 36 Seconds
15 Seconds 16 Seconds 15 Seconds
Super Street Sunset Fly Over & Lawyers Bypass
13.7 Seconds

29. County of Fairfax, Virginia
Colts Neck Road Colts Neck Road
Fox Mill RoadFox Mill Road
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Reston Parkway LOS Results (Cont.)
No-Build
WB DTR
EB DTR
Sunrise Valley Drive
Right In/Right Out
South Lakes Drive
Glade Drive
Lawyers Road
WB DTR
EB DTR
Right In/Right Out
No Left Turns
Sunrise Valley Drive
South Lakes Drive
Glade Drive
Lawyers Road
NB U-Turn
No NB/SB Left Turns
Median U-Turns
Median U-Turns
U-Turns
No NB Lefts
Colts Neck Road
Fox Mill Road
WB DTR
EB DTR
Sunrise Valley Drive
Right In/Right Out
South Lakes Drive
Glade Drive
No NB Lefts
36 Seconds 48 Seconds 36 Seconds
15 Seconds 16 Seconds
15 Seconds
105 Seconds 132 Seconds 105 Seconds
92 Seconds 87 Seconds 92 Seconds
50 Seconds 45 Seconds 50 Seconds
172 Seconds 81 Seconds 99 Seconds
152 Seconds 159 Seconds 151 SecondsLawyers Road
Super Street Sunset Fly Over & Lawyers Bypass
5 Seconds
47 Seconds
25 Seconds

30. County of Fairfax, Virginia
Reston Parkway Volumes
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• Reston Parkway is projected to carry similar
volumes to Fairfax County Parkway (FCP)
2050 PM Peak Hour Volumes
Fairfax County
Pkwy
Reston Pkwy Comparison
Sunrise Valley
Drive
NB Approach 2071 1968 -103
SB Approach 2586 2665 +79
Between DTR
Ramps
NB 2510 2386 -124
SB 2775 3010 +235
Sunset Hills
Road
NB Approach 2343 2543 +200
SB Approach 2062 2154 +92
Baron Cameron
Avenue
NB Approach 2746 1650 -1096
SB Approach 1163 458 -705

31. County of Fairfax, Virginia
Reston Parkway Take Away
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• Reston Parkway carries a significant portion of
north/south traffic in the area
• At grade mitigation to LOS E is challenging
• Grade separations are not appropriate for the
area’s character
• Discuss possibility of accepting locations with
LOS F along Reston Parkway
• Fairfax County Parkway improvements could
improve Reston Parkway

32. County of Fairfax, Virginia
Next Steps
• Advisory Group Meeting Monday, September 12
• Tier 3 VISUM Analysis
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33. County of Fairfax, Virginia
Schedule
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Task Description 2015 May 15 June 15 July 15 Aug 15 Sep 15 Oct 15 Nov 15 Dec 15 Jan 16 Feb 16 Mar 16 April 16 May 16 June 16 July 16 Aug 16 Sep 15 Oct 15 Nov 16 Dec 16 Jan 17
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) - Task complete advance
to Tier 3 Mitigation
3A1 Analyze Future Conditions (2030)
3B Simulation of the Dulles Toll Road
4A Meetings/Presentations
5A Phasing Analysis - Existing Conditions- Ths Task is complete
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
07
08/8/16

34. County of Fairfax, Virginia
Discussion
• Fairfax County Parkway & Spring Street
– Staff recommends Option 1
• Fairfax County Parkway & Sunrise Valley Drive
– Alternatives are Comparable
• Reston Parkway
– Discussion of alternatives and possible approach
– Possible ideas on how to improve Reston Parkway
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35. 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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