Information about development in Fairfax County, major stormwater management project drivers, a functions-based approach to stream restoration and more information about the project is included in the presentation.

1. A Fairfax County, VA, publication
Department of Public Works and Environmental Services
Working for You!
October 26, 2020
Project Overview
Braddock District
Long Branch Central
Watershed Management Area

2. Stormwater Management
Development of Fairfax County Stream Restoration and Water Quality Work Plan
Fairfax County, Virginia
• Land area of approximately 400 square miles
• Population of approximately 1.1 million residents
• Includes Fairfax City, the Towns of Herndon and Vienna, George Mason
University, Fort Belvoir
• Land Use
– Residential 88%
– Commercial 5%
– Industrial 2%
– Open Space 4%
– Other 1%
• MS4 Phase I community
• Stormwater Funding: Stormwater Service
District
• 30 watersheds with over 750 miles of perennial streams
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3. Stormwater Management 3
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Major Stormwater Project Drivers
1. Chesapeake Bay TMDL
Pollutant Load Reduction Requirements
a) Nitrogen: 59,400 pounds/year
b) Phosphorous: 6,500 pounds/year
c) Sediment: 2,700 tons/year
2. Local TMDL’s
a) Sediment (4)
b) Bacteria (7)
c) PCB’s (tidal portions of
Potomac River)
d) Chloride (1)
3. 105 Impaired Waterbodies
2016 Impaired Waters
77 Streams
5 Reservoirs
28 Tidal Embayments
107 Total Impaired Waters
Development of Fairfax County Stream Restoration and Water Quality Work Plan

4. Stream Restoration – Functions-Based Approach
• How well are we restoring functions?
– What’s is the time scale?
– What’s achievable?
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Local TMDLs – direct
measures (benthics, fish,
water chemistry, etc.)
Chesapeake Bay TMDL
or Stream Mitigation
Credits – required
indirect reductions
(modelled) for stream;
can be measured
Stormwater Management

5. DPWES Stormwater Planning Division
Project Location
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Long Branch Central Watershed Management Area
Long Branch Central Watershed
3.71 Square Miles - 8 Miles of Streams
Braddock Road
Little River Turnpike (236)
Capital Betway
(495)
Burke Station Road

6. DPWES Stormwater Planning Division
Project Overview
Project Goals:
• Achieve Long Branch Central TMDL
waste load reduction requirements.
• Provide long-term stability and have
low maintenance.
• Improve water quality within the
Long Branch Central watershed.
• Improve habitat and environmental
health (ecological lift).
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Long Branch Central Watershed Management Area
Failed Stream Bank: Long Branch near
Olde Creek Elementary School
Degraded Outfall: Long
Branch at Laurel Street

7. DPWES Stormwater Planning Division
Who’s Involved
• County Agencies
– DPWES
– FCPA
– NVSWCD
– FCPS
• Design Consultant: Biohabitats, Inc.
• Braddock District Supervisor’s Office
• Identified Stakeholder Groups:
– Friends of Long Branch
– Friends of Accotink Creek
– Earth Sangha
– Stone Haven Civic Association
– Canterbury Woods Civic Association
– Red Fox Civic Association
– Rutherford Civic Association
• Residents
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Long Branch Central Watershed Management Area
Relative Stability & Bank Erosion:
Long Branch Main Stem Downstream of Guinea Road

8. DPWES Stormwater Planning Division
Next Steps
• County agency kick off meeting July 2020
• Agencies designate team members
• Outreach to stakeholders
• Develop data collection work plan
• Develop communications plan
• Capture input
– Agencies
– Residents
– Stakeholders
• Develop Project Implementation Plan
• Implement
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Long Branch Central Watershed Management Area
Undermined Trail Culvert:
Long Branch Tributary Between Rockcrest Dr & Braeburn Dr

9. DPWES Stormwater Planning Division
Project Schedule
• Begin Assessment – Fall 2020
• Complete Restoration Work Plan –
Spring 2021
• Complete First Construction Plans –
Spring 2022
• Begin Construction – Late Fall 2022
• Construction Ongoing – Through
2027
• Warranty, Monitoring and
Maintenance – 2025 through 2030
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Long Branch Central Watershed Management Area
Massive Bank Erosion: Long Branch Tributary in Old Forge Park

10. DPWES Stormwater Planning Division
Project Scope
Assess:
• ~9 miles of stream
• ~150 outfall
• County maintained SW facilities
(optional task)
Restore:
• ~6 miles of stream
• ~75 outfalls
• Renovate county SW facilities
(optional)
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Long Branch Central Watershed Management Area
Undermined Concrete Ditch: Long Branch in Smokewood
Park Downstream of Whiteacre Dr

11. Stormwater Management
• Stream and Outfall Characteristics
– Size, stability, biology, hydraulics/hydrology
• Biology
– Stream organisms, surrounding forests, habitat condition
• Buffer and Floodplain Characteristics
– Width, quality/composition score
• Human Impacts
– Bridges, outfalls, trails, land use practices
• Safety Issues
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Considerations
Gathering Watershed Condition Information
Field Scoping

12. DPWES Stormwater Planning Division
Ensuring Projects Meet Goals
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Long Branch Central Watershed Management Area
• Use tools such as the
Recovery Wheel to
establish goals for each
restoration area
• Ensure goals reflect
stakeholder values
• Create metrics to measure
outcomes
• Establish monitoring
program to track progress
and report to community
Recovery Wheel Example:
Planning Tool Developed by Fairfax County Stormwater

13. DPWES Stormwater Planning Division
Building on Existing Plan
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Long Branch Central Watershed Management Area
• Review proposed projects from
Accotink Watershed Management
Plan
– 32 Structural Projects (stream
restoration, stormwater pond
retrofits, etc.
– 8 Non-structural Projects
(Community outreach, rain barrels,
etc.)
• Update conditions information for
Long Branch Central
• Include stakeholder input
• Identify Project Leads
– Streams & outfalls – DPWES
– Non-structural – Partners
– Future projects – beyond scope of
WMA
• Develop implementation schedule

14. DPWES Stormwater Planning Division
Discussion
Discussion & Questions
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Long Branch Central Watershed Management Area
Old Grade Control Structure: Long Branch Main Stem
Canterbury Woods Downstream of Woodland Way
Project Web Page:
https://www.fairfaxcounty.gov/publicworks/stormwater/pla
ns-projects/long-branch-central-watershed-management-
area-project

15. Additional Information
For additional information, please contact
www.fairfaxcounty.gov/publicworks
Long Branch Central Watershed Management Area
Charles Smith
(703) 324-2467
charles.smith@fairfaxcounty.gov
DPWES Stormwater Planning Division 15
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