This document summarizes a community meeting held by the Fairfax County Department of Public Works and Environmental Services to discuss plans for restoring a section of stream in the Hollin Hills area. The project aims to stabilize eroding streambanks, reduce sediment and nutrient pollution, and improve habitat. The design goals and proposed restoration techniques were presented, including reconnecting the stream to its floodplain and replanting native vegetation. Attendees were invited to provide comments on the preliminary design by May 28th. Construction is planned to begin once final permits are obtained.

1. A Fairfax County, VA, publication
Department of Public Works and Environmental Services
Working for You!
May 20, 2019
Community Meeting
Hollin Meadows Elementary
Paul Spring Branch Segment 2 @ Hollin Hills Stream
Restoration Project
Little Hunting Creek Watershed Plan Implementation

2. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Program Drivers
• State and Federal Regulations
• Chesapeake Bay Agreement
• Partnering states (VA, MD, DC, DE, PA, WV) signed the agreement to restore the bay health and
ecosystem.
• Municipal Separate Storm Sewer System Permit (MS-4)
• Easements rights and responsibility to maintain/upgrade
• Local TMDLs (Total Maximum Daily Loads – sediment, bacteria, PCBs)
• Regulates amounts of pollutants in waterways
• Public Safety
• Erosion control
• Flooding
• Maintenance of existing facilities

3. DPWES Stormwater Planning Division
Meeting Outline
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• Site Location and Project Limits
• Existing Conditions
• Status and General Schedule
• Design Goals
• Proposed Alignment and Access
• Example Projects
• Q&A
Hollin Hills Stream Restoration

4. Little Hunting Creek Watershed
• 7,067 acres in Fairfax
County
• One of the most developed
watersheds in Fairfax
County
• Discharges into Potomac
River
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https://www.fairfaxcounty.gov/dpwes/watersheds/littlehuntingcreek.htm
DPWES Stormwater Planning Division

5. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
~0.04 square miles (23 acres)
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~24% impervious

6. DPWES Stormwater Planning Division
Project Limits
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Hollin Hills Stream Restoration

7. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Existing Conditions – Incised Channels
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8. DPWES Stormwater Planning Division
Existing Conditions Eroding Banks
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Hollin Hills Stream Restoration

9. DPWES Stormwater Planning Division
Existing Conditions Eroding Banks
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Hollin Hills Stream Restoration

10. DPWES Stormwater Planning Division
Existing Conditions Access to Culvert
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Hollin Hills Stream Restoration

11. 11
Existing Conditions Unhealthy Trees
DPWES Stormwater Planning Division
Hollin Hills Stream Restoration
Aging forest threatened by erosion, herbivory and
non-native invasive plants.

12. 12
Existing Infrastructure
DPWES Stormwater Planning Division
Hollin Hills Stream Restoration
Popkins entrance

13. DPWES Stormwater Planning Division
Status and General Schedule
• Data Collection (Completed)
• Stream Restoration Design Process (In progress)
– Pre-Concept Plan Development (Completed)
– Concept (35%) Design Plan Development (Completed)
– Field Walk (Completed)
– Preliminary (65%) Design Plan Development (late summer 2019)
– Final Design Plan Development (After 65%)
– Construction Documents (After final design and permits)
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Hollin Hills Stream Restoration

14. DPWES Stormwater Planning Division
Status and General Schedule (continued)
• Construction (± 12 months)
– Construction date dependent on future funding
– Bidding and Contract Award
– Community Meeting
– Construction Begins
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Hollin Hills Stream Restoration

15. DPWES Stormwater Planning Division
Design Team
• Design Team includes:
– Members of the Hollin Hills Civic Association
– Members of the Hollin Hills community
– County staff: Project Manager, Construction Manager, Wastewater, Urban Forester,
Stormwater Ecologist
– Design Engineers: Stantec
– History Commission
– Northern Virginia Soil and Water Conservation District
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Hollin Hills Stream Restoration

16. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Design Goals
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What are the design goals?
• Stabilize 1,200 LF of stream
• Reduce excess sediment from being transported downstream
• Reduce excess nutrients from entering the waterway
• Improve aesthetics
• Reduce hazards (steep, eroding banks)
• Reconnect stream to floodplain
• Improve riparian buffers, park natural resources

17. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
What does 253 lbs of TN look like?
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This concept
estimates saving at
least 116 lb/yr TP
and 253 lb/yr TN
from waterway

18. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
What does 253 lbs of TN look like?
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• One estimate has it costing $350/lb/yr TN removed (sewage treatment
system = $88,550 /yr)
• “An analysis from the Chesapeake Bay Foundation, for instance, found
that putting the “pollution diet” in place—which is just one piece of
the Chesapeake Bay Watershed Agreement—would provide annual
benefits worth $129.7 billion: more than 65 times the investments cited
in the 2017 Chesapeake Bay Restoration Spending Crosscut.”
• One nutrient credit bank (Belle Meade Nutrient Bank) is turning 48.91
acres of hay field into wetland to generate 188.30 lbs of TN credit

19. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Priority 1
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20. DPWES Stormwater Planning Division
Hollin Hills Stream Restoration
Example In-Stream Structures
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Reinforced Bed
Rock Steps
Boulder Riffle

21. DPWES Stormwater Planning Division
Hollin Hills Stream Restoration
Stream Bank Reinforcement
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Native Vegetation
In-Stream Log SillToe-Slope Protection

22. DPWES Stormwater Planning Division
Hollin Hills Stream Restoration
Construction
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23. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Design
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Upper
Middle

24. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Design
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Middle
Lower

25. DPWES Stormwater Planning Division
Hoolin Hills Stream Restoration
Pre-Restoration
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26. DPWES Stormwater Planning Division
Hollin Hills Stream Restoration
Post-restoration
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27. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Design – Tree Preservation
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• Surveyed 238 Trees
• This plan would remove 51 trees 12” or greater
• Up to 37 of these trees could be reused on site
Brush Habitat
Large Log Habitat

28. Hollin Hills Stream Restoration
DPWES Stormwater Planning Division 28
Construction Example
Pre-Construction 6 months post-Construction

29. 29DPWES Stormwater Planning Division
Hollin Hills Stream Restoration
Examples – Quander Road Outfall
Pre-Construction
6 months post-Construction
18 months post-Construction

30. Pre-Construction Construction
Post Construction After plant establishmentPost-Construction
Hollin Hills Stream Restoration
DPWES Stormwater Planning Division
Examples – Big Rocky Run Tributary
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31. DPWES Stormwater Planning Division
Highlights & Next Steps
• Stream project requested by the community as erosion is getting
worse
• Evaluation and design to improve the stream condition and prevent
further degradation
• Civic Association provided easements to access property
• Extensive replanting and non-native invasive control will be
incorporated in later design phases
• Expecting design completion early in 2020
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Hollin Hills Stream Restoration

32. DPWES Stormwater Planning Division
Communication
• Comments for this plan version due May 28th
• Provide them directly to Project Manager (Meghan)
• Provide them to community representatives
• Refinements of plan sets as we move forward will refine this concept,
do not expect major changes
• All refinements will be continued to be reviewed by Project Team and
regulatory organizations (e.g. History Commission, Army Corps of
Engineers)
• All refinements will be posted in Sharefile for review
• Continue to provide comments and suggestions
• Planned Next Community Meeting – just before construction
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Hollin Hills Stream Restoration

33. DPWES Stormwater Planning Division
Contact Information
Design
Meghan Fellows – Project Manager
703-324-5807
Meghan.Fellows@fairfaxcounty.gov
Fairfax County Stormwater Planning Division
Department of Public Works and Environmental Services (DPWES)
12000 Government Center Parkway
Suite 449
Fairfax, Virginia 22035
www.fairfaxcounty.gov/publicworks/stormwater
To request this information in an alternate format call 703-324-5500, TTY 711
Presentation Website
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