This document summarizes a stream stabilization project along Scotts Run in Fairfax County, VA. The project aims to stabilize 650 linear feet of stream bank and bed to reduce sediment and nutrient inputs. It will improve habitat and control flooding. Construction is scheduled to begin in spring 2017 and take 3-4 months. It will include installing structures like plunge pools, cross vanes, and rock weirs. Native vegetation will be planted afterward. The project meets regulatory requirements and aims to improve watershed conditions through erosion control and flood mitigation.

1. A Fairfax County, VA, publication
Department of Public Works and Environmental Services
Working for You!
Scotts Run Tributary
at Windy Hill Road
Stream Stabilization Project
May 2016

2. Stormwater Planning Division
Agenda
Project Scope
Background
Goals and Objectives
Existing Conditions
Project Concept
Next Steps
Contact Information
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3. Stormwater Planning Division
Stormwater Program Regulatory Drivers
• National Pollutant Discharge Elimination System (NPDES)
• Virginia Stormwater Management Program (VSMP)
– Municipal Separate Storm Sewer Permit (MS4)
– Discharge from approximately 7,000 storm drain outfalls
– Includes watershed planning and project implementation
• Total Maximum Daily Loads (TMDLs)
– Chesapeake Bay
– Local Streams
– Establishes pollutant loading budget for a given impaired water
body to meet water quality standards
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4. Scotts Run Watershed
• 3,860 acres in Fairfax County
• 30% impervious of mostly low
density residential land use
• Drains significant commercial
and medium-density resident
areas located near Tysons
Corner
• Scotts Run discharges into the
Potomac River
• Watershed Management Plan
identifies frequent flooding at
Scotts Run Road
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http://www.fairfaxcounty.gov/dpwes/watersheds/middlepotomac.htm
Stormwater Planning Division

5. Stormwater Planning Division
Project Objectives
Restore up to 650 linear feet of stream from Windy Hill Road to
Box Elder Court:
 Stabilize streambed and banks
 Reduce sediment and nutrient inputs into stream system
 Improve habitat
 Maintain close coordination with stakeholders
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6. Stormwater Planning Division
Social Goals
1. Maintain open dialog and share information.
2. Coordinate with all the stakeholders and the community.
3. Design Team:
o Rinker Design Associates, P.C.
o Utilities Design and Construction Division
o Stormwater Management
o Stormwater Planning Division
o Maintenance and Stormwater
Management Division
o Urban Forestry
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7. Stormwater Planning Division
Environmental Benefits
Improve watershed conditions and reduce downstream
impacts through….
Controlling quantity
Mitigate flooding where possible
Controlling velocity
Reduce erosion
Protect infrastructure
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8. Stormwater Planning Division
Project Location
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Windy Hill Road
Box Elder Court
Scotts Run Road
Project Limits
Lewinsville Road
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9. Stormwater Planning Division
Drainage Area
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10. Stormwater Planning Division
Existing Conditions
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11. Stormwater Planning Division
Existing Conditions
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12. Stormwater Planning Division
Existing Conditions
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13. Stormwater Planning Division
Existing Conditions
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Existing Conditions

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Existing Conditions

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Existing Conditions
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Existing Conditions

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Existing Conditions

19. Stormwater Planning Division
Typical Structures Used – Plunge Pool
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20. Stormwater Planning Division
Typical Structures Used – Cross Vanes
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21. Stormwater Planning Division
Typical Structures Used – Rock Weirs
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22. Stormwater Planning Division
Typical Structures Used – Boulder Toe
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23. Vegetation
• Coordinate tree
preservation and
removal with
Urban Forestry
• Native trees,
shrubs, and plugs
will be planted
• Native seed mix
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24. Stormwater Planning Division
Tentative Construction Access
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Windy Hill RoadScotts Run Road

25. Stormwater Planning Division
Before and After Stream Restoration
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26. Stormwater Planning Division
Construction Access
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• Timber matting
along the length
of the access
route
• Safety fencing
around the site

27. Stormwater Planning Division
Construction Example
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28. Stormwater Planning Division
Construction Example
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29. Stormwater Planning Division
Construction Example
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30. Stormwater Planning Division
Growing Season Following Construction Completion
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31. Stormwater Planning Division
One Year After Construction Completion
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32. Stormwater Planning Division
Three Years After Construction Completion
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Before and After Examples
Flatlick Confluence
January 2011 September 2015

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Before and After Examples
Big Rocky Run II
April 2011 September 2015

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2011
2013 2015
Before
Before and After Examples
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i
d
l
e
P
a
t
h

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Next Steps – Schedule
• Complete Preliminary Design- July 2016
• Complete 95% Design- September 2016
• Community Meeting- September 2016
• Complete Final Design- Late Fall 2016
• Construction:
• Start- Spring 2017
• Length- 3 to 4 months (constructed in phases)
• Planting may take place in the fall

37. Stormwater Planning Division
Online Resources
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Stormwater Planning Division Website
http://www.fairfaxcounty.gov/dpwes/stormwater/
Fairfax County Watershed Planning
http://www.fairfaxcounty.gov/nvswcd/newsletter/planning.htm
Scotts Run Watershed Plan
http://www.fairfaxcounty.gov/dpwes/watersheds/middlepotomac.htm
EPA Water Quality Laws & Regulations
http://www.epa.gov/water/laws.html
Please sign in and provide your
contact information to be
included in project progress
updates

38. Stormwater Planning Division
Contact Information
Contact Information
Design
Catie Torgersen– Project Manager
703-324-5189
Catherine.Torgersen@fairfaxcounty.gov
Fairfax County Stormwater Planning Division
703-324-5500 TTY 711
12000 Government Center Parkway
Suite 449
Fairfax, Virginia 22035
www.fairfaxcounty.gov/dpwes/stormwater
To request this information in an alternate format call 703-324-5500, TTY 711
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