Future wastewater flows in northern Fairfax County exceed existing system capacity Treatment capacity is available in Noman M. Cole Jr. Pollution Control Plant in Lorton, VA New pipes and pumps are needed to move future flows to treatment plant NEXT STEPS Field investigations / surveys Finalize alignments and pump station layout Use of open cut excavation Use of trenchless methods Easement acquisition needed Develop traffic control plans

1. A Fairfax County, VA, publication
Department of Public Works and Environmental Services
Working for You!
Tysons West Wastewater Conveyance Systems Modifications
Project
Wastewater Project – Virtual Community Meeting
May 10, 2022

2. Administrative Items
Tysons West Wastewater Conveyance Project
• Attendee Virtual Sign-In (2 options)
o Use Q/A on MS Teams – Name, Property Address, Email, Phone Number
o Email agata.fallon@fairfaxcounty.gov - Name, Property Address, Email, Phone
Number
• The Q/A is available and monitored throughout the presentation
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 2
Please type your questions in the Q/A throughout the presentation!

3. Meeting Agenda
Tysons West Wastewater Conveyance Project
• Welcome
• Supervisor Walter Alcorn, Hunter Mill District
• Mike Wing, Providence District
• Project Presentation
• Questions and Answers
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 3

4. A Fairfax County, VA, publication
Department of Public Works and Environmental Services
Working for You!
Tysons West Wastewater Conveyance Systems Modifications
Project
Wastewater Project – Virtual Community Meeting
May 10, 2022

5. Project Team Introductions
Tysons West Wastewater Conveyance Project
• Fairfax County
o Agata Fallon, PE, Fairfax County Project Manager
• CDM Smith
o Kraig R. Schenkelberg, PE, BCEE, PMP, Project Technical Leader
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 5

6. Goals
Tysons West Wastewater Conveyance Project
• Inform the community about the upcoming project
• Share results of the study
• Understand community concerns
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 6

7. Presentation Agenda
Tysons West Wastewater Conveyance Project
• Project Needs and Goals
• Tysons West Study
• Next Steps - Design
• Next Steps - Construction
• Project Schedule
• Continuing Engagement
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 7

8. Growth in Northern Fairfax County – Wastewater Flows are Increasing
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 8
• Future wastewater flows in
northern Fairfax County exceed
existing system capacity
• Treatment capacity is available in
Noman M. Cole Jr. Pollution
Control Plant in Lorton, VA
• New pipes and pumps are needed
to move future flows to treatment
plant

9. Growth in Northern Fairfax County – Project Locations
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 9
Difficult Run PS
Carderock Sewer
Rehabilitation
Tysons East PS
Accotink
Gravity Sewer
Tysons West PS

10. Tysons Area Flows and Needs
Tysons West Wastewater Conveyance Project
• Existing system installed 1960’s
• Existing infrastructure improvements
needed
• Future flows exceed existing system
capacity
• Capacity improvements needed
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 10

11. Tysons West Study
Tysons West Wastewater Conveyance Project
• Tysons West study identified the need for
o Larger sewer collection
o Larger pump station
o New force main to treatment plant in Lorton
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 11

12. Sewer Collection
Tysons West Wastewater Conveyance Project
• Collect flow from new
development
• Divert flow from existing
interceptor pipe
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 12

13. Sewer Collection Evaluation Criteria
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 13
Goal to minimize impacts
Community
• residential
• commercial
• traffic
• parking
• noise/dust
Hydraulics
factors
• gravity flow to
pump station
• length
Constructability
• space available
• depth of pipe
• existing
facilities and
utilities
Environmental
• streams
• parks
• trails
• trees
• wetlands
• open spaces
Land Rights
• easements
• rights of way
Utilities
• existing utility
coordination
• temporary
utilities
• utility
relocations
Costs
• construction
• maintenance
and operation
Stakeholders
• public
• permitting
• regulations

14. Sewer Collection Evaluation Criteria
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 14
Goal to minimize impacts
Community
• residential
• commercial
• traffic
• parking
• noise/dust
Hydraulics
factors
• gravity flow to
pump station
• length
Constructability
• space available
• depth of pipe
• existing
facilities and
utilities
Environmental
• streams
• parks
• trails
• trees
• wetlands
• open spaces
Land Rights
• easements
• rights of way
Utilities
• existing utility
coordination
• temporary
utilities
• utility
relocations
Costs
• construction
• maintenance
and operation
Stakeholders
• public
• permitting
• regulations

15. Sewer Collection Selected Alternative
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 15

16. Pump Station
Tysons West Wastewater Conveyance Project
• Existing facility is at a low point
for gravity flow
• Increase size of pump station
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 16

17. Pump Station Expansion
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 17
Goal to minimize impacts
Community
• residential
• commercial
• traffic
• parking
• noise/dust
Hydraulics
factors
• size
• gravity flow to
pump station
Constructability
• space available
• existing
facilities and
utilities
Environmental
• streams
• parks
• trails
• trees
• wetlands
• open spaces
Land Rights
• easements
• rights of way
Utilities
• continuous
service
• existing utility
coordination
• utility
relocations
Costs
• construction
• maintenance
and operation
Stakeholders
• public
• permitting
• regulations

18. Pump Station Expansion Selected Alternative
Tysons West Wastewater Conveyance Project
• ~ 25 million gallons
• ~ 1 acre facility
• Construction Estimate ~
$37 million
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 18

19. Force Main
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 19
• Transport flow to Lorton via
Accotink Interceptor

20. Force Main Evaluation Criteria
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 20
Goal to minimize impacts
Community
• residential
• commercial
• traffic
• parking
• noise/dust
Hydraulics
factors
• length
• elevation
difference
• number of
bends
• pressure losses
Constructability
• space available
• depth of pipe
• existing
facilities and
utilities
Environmental
• streams
• parks
• trails
• trees
• wetlands
• open spaces
Land Rights
• easements
• rights of way
Utilities
• existing utility
coordination
• temporary
utilities
• utility
relocations
Costs
• construction
• maintenance
and operation
Stakeholders
• public
• permitting
• regulations

21. Force Main Selected Alternative
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 21
• ~ 27,500 feet
• 36-inch pipe
• Construction Estimate ~
$44.5 million

22. Selected System
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 22
• New ~ 9,200 feet sewer
• New ~ 25 million gallons per day pump
station
• New ~ 27,500 feet force main
• Construction Estimate ~ $ 106 million

23. Design – Next Steps
Tysons West Wastewater Conveyance Project
• Field investigations / surveys
• Finalize alignments and pump station layout
• Use of open cut excavation
• Use of trenchless methods
• Easement acquisition needed
• Develop traffic control plans
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 23

24. Open Cut Pipeline Construction
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 24
During Construction After Construction

25. Trenchless Pipeline Construction
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 25

26. Trenchless Pipeline Construction
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 26
During Construction
After Construction

27. Pump Station Construction
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 27
During Construction After Construction

28. Schedule and Key Milestones
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 28
May 2022
Review Public Meeting
Feedback and Develop
Design
May 2022
Public Meeting
Project Introduction
May 2023
(Anticipated) Public Meeting
May 2024
(Anticipated) Public Meeting
March 2023
Gravity Sewer Design
Completed
April 2023
Pump Station
Design Completed
July 2026
Construction
Completed
May 2024
Force Main
Design Completed

29. Summary of Project Needs and Benefits
Tysons West Wastewater Conveyance Project
• Critical project to provide continuous reliable service
• Protection of public health and quality of life
• Need to start now
• Mitigate impacts to community and environment
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 29

30. Our Commitment
Tysons West Wastewater Conveyance Project
Capital Facilities/Wastewater Design and Construction Division/Collections Branch 30
Engagement will continue throughout
project until completion
Agata Fallon, PE
703.324.5613
agata.fallon@fairfaxcounty.gov
https://www.fairfaxcounty.gov/publicworks/capital-projects/tysons-west-wastewater-system-enhancements