This project included 3,000 linear feet of stormwater improvements that promote infiltration, improve water quality, and safely convey stormwater through the neighborhood to a stream.
Narrative Report on 3rd NNational Simultaneous Earthquake Drill2023.docx
Franklin Park Chesterbrook Neighborhood Project Highlights
1. A Fairfax County, VA, publication
Department of Public Works and Environmental Services
Working for You!
FRANKLIN PARK AND CHESTERBROOK
NEIGHBORHOOD
STORMWATER IMPROVEMENT PROJECT (SIP)
Stormwater Management
March, 2017
“Improving our Neighborhoods and Protecting
our Streams One SIP at a Time”
2. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
PROJECT TEAM
• Fairfax County Department of Public Works and Environmental
Services – Project Management/Maintenance
• Stormwater Planning Division (SWPD)
• Utilities Design and Construction Division (UDCD)
• Maintenance and Stormwater Management Division (MSMD)
• Urban Forestry Management Division (UFMD)
• Northern Virginia Soil and Water Conservation District (NVSWCD)
• Sagres Construction Corporation - Contractor
• Michael Baker International/Stantec – Design Engineers
• Versar/ATR Associates, Inc. – Concept Design
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3. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Watershed Plan
• Middle Potomac Watershed Plan
3
Neighborhood Stormwater
Improvement Project Area
Pilot Project Location
http://www.fairfaxcounty.gov/dpwes/watersheds/
4. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Project Background
• Older neighborhood originally built in the 1950s.
• Redevelopment promoted by location and value of land in
McLean, VA.
• Development includes large additions or complete teardowns
and construction of new, larger homes on existing lots.
• No offsite public improvements: Road, Sanitary, Stormwater, etc.
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Example home teardown and rebuild with changes to grade and per
lot imperviousness.
Before After
5. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Project Background – Existing Challenges
• Cumulative increase in
imperviousness results in
increased stormwater runoff
volume
• Inadequate or lacking stormwater
conveyance systems causes water
to flow across roads, over yards,
and around homes causing
flooding and erosion problems
• Receiving stream experiencing
erosion and degradation.
5
Eroding stream, a tributary to Little Pimmit
Run, downstream of storm drain outfalls
Runoff flows over road and into yards
6. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Existing Drainage Conditions
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Infrastructure Capacity
Stream Bank Erosion
Overland Drainage
Representative
runoff flow path
7. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Residential Infill Development: 1997 - 2010
7
Compare change in the number of homes and their size
shown on the next slide. The parcels highlighted in yellow
had homes with additions or were completely
redeveloped between 1997 and 2010.
8. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Residential Infill Development: 1997 - 2010
8
Compare change in the number of homes and their size
shown on the previous slide. The parcels highlighted in
yellow had homes with additions or were completely
redeveloped between 1997 and 2010.
9. Franklin Park and Chesterbrook Pilot Project
Stormwater Management
Existing Stormwater Infrastructure and Stream
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2015Existing Storm Drains
Stream Channel
Parcel Boundary
10. Franklin Park and Chesterbrook Pilot Project
Stormwater Management
Predevelopment Conditions: 1937 Photograph
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1937
11. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Pilot Project Goals
• Reduce yard flooding and
erosion
• Collect runoff at the source
• Improve water quality
• Reduce discharge energy at
outfall
• Use innovative & functional
designs
• Make it aesthetically pleasing
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12. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Stormwater Improvements
1212
Amended
Swales
Infiltrating
Trenches
Permeable
Pavement
Stormwater
Chambers
Note: Infiltrating trenches
separated because of a
surface condition (e.g.
driveways were generally
connected with PVC pipes.
13. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Construction – Utility Relocation
• Utility coordination and relocation of
public and private systems
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Sanitary Sewer Line and Private Laterals
Gas Line Relocation
Water Line Relocation
14. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Construction – Bioretention and Infiltration Swales
• A total of 3,000 linear feet of
stormwater improvements were
made that promote infiltration,
improve water quality and safely
convey stormwater through the
neighborhood to the local stream.
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Amended Soil
Gravel Base and Under Drains
Final Grass Cover
15. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Construction – Stormwater Chamber & Infiltration System
• Installation of underground chambers
that provide storage and promote
infiltration.
• Grass sod provides an immediate
finished look that fits into the
community landscape and simplifies
long term maintenance.
15
Before
Before – Concrete Ditch
After – Grass Swale with Underground
Chambers with Infiltration System
16. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Construction – Infiltration Swales with Check Dams
• Check dams made with native
soil and imbricated stone slow
down water and promote
infiltration.
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Check Dams
Imbricated Stone Check Dams
17. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Construction – Road Improvements
• Partnered with Virginia
Department of Transportation to
coordinate and fund repaving of
roads within project limits
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Roadway reconstructed
Milled and Resurfaced
Legend
• Project included:
– Milling and paving
– Reconstructed Patton Terrace
with a crown to improve
drainage
– Shoulder stabilization
– Replacement of existing
driveway culverts
Porous paver parking pad over chamber
18. Franklin Park and Chesterbrook Neighborhood Stormwater Improvement Project
Stormwater Management
Additional Information
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Matt Meyers, Chief, Watershed Projects Implementation Branch
Matthew.Meyers@fairfaxcounty.gov
703-324-5651
Dipmani Kumar, Project Manager
Dipmani.Kumar@fairfaxcounty.gov
703-324-4612
www.fairfaxcounty.gov/dpwes