scotts run tributary at windy hill road: stream stabilization project
TRANSCRIPT
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
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Agenda
Project ScopeBackgroundGoals and ObjectivesExisting ConditionsProject ConceptNext StepsContact Information
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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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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
http://www.fairfaxcounty.gov/dpwes/watersheds/middlepotomac.htm
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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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Social Goals1. 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 Divisiono Stormwater Management
o Stormwater Planning Divisiono Maintenance and Stormwater Management Division
o Urban Forestry
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Environmental Benefits
Improve watershed conditions and reduce downstream impacts through….
Controlling quantityMitigate flooding where possible
Controlling velocityReduce erosionProtect infrastructure
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Project Location
Windy Hill Road
Box Elder Court
Scotts Run RoadProject Limits
Lewinsville Road
495
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Drainage Area
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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
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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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Typical Structures Used – Plunge Pool
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Typical Structures Used – Cross Vanes
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Typical Structures Used – Rock Weirs
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Typical Structures Used – Boulder Toe
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Vegetation
• Coordinate tree preservation and removal with Urban Forestry
• Native trees, shrubs, and plugs will be planted
• Native seed mix
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Tentative Construction Access
Windy Hill RoadScotts Run Road
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Before and After Stream Restoration
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Construction Access
• Timber matting along the length of the access route
• Safety fencing around the site
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Construction Example
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Construction Example
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Construction Example
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Growing Season Following Construction Completion
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One Year After Construction Completion
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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
Bridle Path
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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
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Online ResourcesStormwater Planning Division Websitehttp://www.fairfaxcounty.gov/dpwes/stormwater/
Fairfax County Watershed Planninghttp://www.fairfaxcounty.gov/nvswcd/newsletter/planning.htm
Scotts Run Watershed Planhttp://www.fairfaxcounty.gov/dpwes/watersheds/middlepotomac.htm
EPA Water Quality Laws & Regulationshttp://www.epa.gov/water/laws.html
Please sign in and provide your contact information to be included in project progress updates
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Contact InformationContact Information
DesignCatie Torgersen– Project Manager
Fairfax County Stormwater Planning Division703-324-5500 TTY 711
12000 Government Center ParkwaySuite 449
Fairfax, Virginia 22035www.fairfaxcounty.gov/dpwes/stormwater
To request this information in an alternate format call 703-324-5500, TTY 711