Dead Run Segment One Stream Restoration Project

A Fairfax County, VA, publication

Department of Public Works and Environmental Services

Working for You!

Dead Run Segment One Stream Restoration ProjectPublic MeetingDominican Retreat House

June, 2015

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Dead Run Segment 1 Stream Restoration Project

Stormwater Planning Division

Meeting Outline

• Fairfax County Stormwater Management• Countywide Watershed Plan Implementation• Project Scope, Status, and Next Steps• Concept Plan Overview

– Basis for design– Tree save options– Floodplain analysis and review of more frequent storm impacts– Buffer restoration measures– Examples

• Q&A• Walk to site

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DPWES Organization

Department of Public Works and Environmental Services

Land Development

Services

CapitalFacilities

Solid Waste Stormwater


Maintenance and Stormwater

Management Division

Wastewater

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Stormwater Infrastructure

• Conveyance System– 1,600 miles pipe and

paved channel– 43,000 structures– 6,800 outfalls

• Management Facilities– 1,540 County Maintained – 3,720 Privately Maintained

• State Regulated Dams

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Service Drivers

In response to The Clean Water Act of 1972…

• National Pollutant Discharge Elimination System (NPDES)• Virginia Stormwater Management Program (VSMP) Regulations• Municipal Separate Storm Sewer Permit (MS4)• Total Maximum Daily Loads (TMDLs)

– Chesapeake Bay– Local Streams

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Dead Run– Stream Conditions

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Countywide Watershed Planning

“Healthy Watersheds, Healthy Communities”

• 30 Designated Watersheds• All 15 watershed plans have

been adopted by Fairfax County

http://www.fairfaxcounty.gov/dpwes/watersheds/

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Middle Potomac Watershed Plan

• Watershed Characterization– Water Quality Monitoring– Land Use Change– Pollutant Loading

• Structural Project– 25 year plan

• Non-Structural Practices– Policy and Regulations

http://www.fairfaxcounty.gov/dpwes/watersheds/

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Dead Run Watershed Plan

• Dead Run has a drainage area just over 3 mi2

• 24 priority projects identified in the watershed management plan

• Pond retrofits• LID Stormwater Enhancements• Stream Restoration• Neighborhood Stormwater

Improvementshttp://www.fairfaxcounty.gov/dpwes/stormwater/projects/project_list.htm

http://www.fairfaxcounty.gov/dpwes/stormwater/projects/project_list.htm

http://www.fairfaxcounty.gov/dpwes/stormwater/projects/project_list.htm

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Partnership LID Stormwater Enhancements - Dolley Madison Library

Approximately 1/3 of the roof is covered in vegetation. The benefits of a “living roof” include:

• Reduces the amount of stormwater runoff• Absorbs air pollution and carbon dioxide• Reduces the energy needed to cool the building in summer

Vegetated Roof- Delosperma and Allium plants in bloom

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Partnership LID Stormwater Enhancements - Dolley Madison Library

Sustainable Site Design

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Stream Monitoring Program

Study Objectives

1. Generate long-term monitoring data.

2. Evaluate relations between observed conditions/trends and BMP implementation.

3. Transfer the understanding gained to other less-intensively monitored watersheds.

http://va.water.usgs.gov/projects/ffx_co_monitoring.htm

13Stormwater Planning Division


Stream Restoration Pictures

Government Center Stream Restoration - Before & After

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Stream Restoration

Dead Run In Mclean Central Park – Before & After

Drainage Area(acres)

Phosphorous Removal(lbs/yr)

Nitrogen Removal(lbs/yr)

Sediment Removal(tons/yr)

415 15 283 3

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Dead Run – Stream Restoration



Dead Run –Stream Restoration

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August 2014January 2010



Project Limits

Segment 1– Dominican Retreat• 2,000 Linear Feet

• Extends to Old Dominion Drive

• Residential lots along Merrimac Drive and Van Ness Court

18Stormwater Planning Divison


Project timeline• Project initiated: Fall, 2013.

• Surveys and assessment completed: Winter, 2013

• Pre-concepts submitted: April, 2014

• First public meeting – April 23, 2014

• Acquired floodplain and storm drainage easement on the Dominican Retreat property – Ongoing

• Public meeting with residents of surrounding properties – June 10, 2015



Next steps with target dates

• Receive concept design comments from residents

• Inform residents of locations where project abuts their property and where work will take place within existing easements on their property

• Develop 95% design plans by September, 2015

• Final design phase public meeting, late September, 2015

• Final plan authorization and bidding phase – TBD based on funding and approved budget

• Target is early, 2016

• Pardon Our Dust meeting with residents and contractor before issuing construction notice to proceed.

Agenda

1 Basis for Design

2 Trees

3 Design Plan

4 Critical Erosion Areas

5 Pedestrian Bridge Replacement

1 Basis for Design

• Stable Channel• Understanding of

Floodplain• Address Erosion

1 Basis for Design • Natural Channel Design (NCD) Approach – Reference Reach, Analytical,

Regional Relationships and hydraulic analysis

• Stream Pattern, Profile and Section

• Range of Values for Stable Stream Pattern

• Tree Loss is Unavoidable but Provides Opportunity to Improve Riparian Diversity

1 Basis for Design • Establish Goals:

• 1. Improve Flow Conditions in the Channel through Adjustments to Plan/Profile/Section

• 2. Create a Stable Channel by Reducing Bed/Bank Erosion that has Benefit of Reducing Contributions of Nitrogen and Phosphorus (i.e. Water Quality Improvement)

• 3. Improve Channel Geomorphology and Opportunities for Species Diversity (i.e. Use Structures to Stabilize Channel and Create Pool Habitats)

• 4. No-Rise / No-Impact of the Floodplain

2 Trees

12” and Larger Trees:• ~190 trees 12” and larger assessed within the project area• ~19 trees 12” and larger are “at risk”

• ~11 of the “at risk” trees may be removed

• Low Diversity of Species: ~45% tuliptree, ~24% red maple• ~39 Trees proposed to be removed

• A few additional trees maybe removed for new storm pipe to address drainage issues.

3 Design Plan - Overall

Map of the entire project limits with property lines and easements shown


Map of the entire project limits with property lines and easements shown



3 Design PlanExhibits where the limits of disturbance enters individual property owners’ lots








Left Bank

Left Bank

Right Bank

Driveway

5 Pedestrian Bridge – Wood Bridge

Two new bridges and one fair weather crossing.


Two new bridges locations

Bridge #1Bridge #2

5 Pedestrian Bridge – Fair Weather Crossing

Two new bridges and one fair weather crossing.


Fairweather Crossing

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Joe Riley-Ryan, [email protected]

Dipmani Kumar, [email protected]

Matt Meyers, [email protected]

Stormwater Planning DivisionDepartment of Public Works and Environmental ServicesFairfax County12000 Government Center Parkway, Suite 449Fairfax, Virginia 22035

www.fairfaxcounty.gov/dpwes/stormwater

• Contact Information

A Fairfax County Publication, April 2014ADA Statement: To request this information in an alternate format call 703-324-5500, TTY 711

mailto:[email protected]



http://www.fairfaxcounty.gov/dpwes/stormwater

Date post:	14-Aug-2015
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Dead Run Segment One Stream Restoration Project

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