The Flatlick Sewer Rehabilitation Project included rehabilitation of approximately 2,500 linear feet of existing 24-inch diameter pipe and 650 linear feet of existing 15-inch diameter pipe using the Cured in Place Pipe (CIPP) lining method. The lining was cured using UV Light. In addition, 11 manholes were rehabilitated throughout the Flatlick Branch stream valley in Chantilly, Virginia. This project was substantially complete on January 4, 2021.

1. A Fairfax County, VA, publication
Department of Public Works and Environmental Services
Working for You!
Project No. WW-000007-014 C & D
Sully District
February 8, 2021
Flatlick Sewer Rehabilitation Project
Phase 1 and 2

2. Project Details
Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Description:
The Flatlick Sewer Rehabilitation Project included rehabilitation of approximately 2,500 linear feet of existing 24-inch
diameter pipe and 650 linear feet of existing 15-inch diameter pipe using the Cured in Place Pipe (CIPP) lining
method. The lining was cured using UV Light. In addition, 11 manholes were rehabilitated throughout the Flatlick
Branch stream valley in Chantilly, Virginia. This project was substantially complete on January 4, 2021.
Project Overview:
• Cured-in-place pipe lining (cured using UV light)
• Manhole rehabilitation using cementitious and epoxy coatings
• Bypass pumping system
• 3,000 linear feet of access road
• Permitting: US Army Corps of Engineers Nationwide Permit #12, Virginia Department of Transportation Land Use
Permit, Fairfax County Park Authority
• Challenge – maintaining access roads and bypass pumping operations during flooding events
Project Team:
• Matt Doyle, P.E. - Wastewater Design and Construction Division
• Suzy Harding, P.E. - Wastewater Design and Construction Division
• Colleen Block, P. E. - Wastewater Design and Construction Division
• Tom Richardson, P.E. - Wastewater Collection Division
• Shwan Fatah, P.E. - Wastewater Collection Division
• Arcadis - Engineer
• Flippo Construction Company - Contractor

3. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Sully District, Tax Map No. 44-2
Project is located along
Flatlick Branch from
Lee Jackson Memorial
Highway to Walney
Road.

4. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Construction of Mulch & Mat Access Roads
Mulch and timber-mat access roads
were installed to reach the sewers in
the Flatlick Branch stream valley.

5. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Tree Protection
Tree protection

6. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Jersey Barriers and Steel Plates to Control Flooding
Various measures
were used to
mitigate effects of
flooding on the
construction site,
including Jersey
Barriers and steel
plates to hold
matting in place.

7. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Bypass Pumping System
Laying out bypass piping
at Phase 1 Construction
Entrance
Bypass pumps and piping
configuration at Phase 1
Construction Entrance

8. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Bypass Pumping System
Pressure testing the
bypass pumping system
Piping in discharge manhole.
Piping in suction manhole.

9. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Bypass Pumping System: Bypass Piping
Bypass piping laid out along Phase 2 access road

10. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Manhole Rehabilitation
MH 006 epoxy coating and new steps Backfilled phase 1 suction manhole
Surface
preparation of
MH for lining

11. Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
UV Cured-in-Place Pipe Lining Equipment
UV light train
Video
monitoring
during lining
operation
Unloading liner

12. Before After
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Flatlick Sewer Rehabilitation Project Phase 1 & 2
Manholes Before and after Lining
Brick manhole channel
Deteriorating manhole steps and concrete
Rehabilitated manhole with epoxy coating of entire interior
and new steps (plastic-wrap removed after epoxy application)

13. Before After
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Flatlick Sewer Rehabilitation Project Phase 1 & 2
Sewer Pipes Before and after Lining
Mild offset joints and cracks
Infiltration
Infiltration
Deteriorated concrete: Aggregate
and reinforcement visible
Cured-in-place pipe: Addresses the “before” defects

14. Additional Information
For additional Information, please call
www.fairfaxcounty.gov/publicworks
Flatlick Sewer Rehabilitation Project Phase 1 & 2
Capital Facilities/Wastewater Design and Construction Division/Collections Branch
Sharon North, M.A., Section Chief, Communications
703-324-8455, TTY 711
Sharon.North@fairfaxcounty.gov
or
Irene Haske, Communications Specialist
703-324-5821, TTY 711
Irene.Haske@fairfaxcounty.gov