Donaldson Run Tributary B Stream Restoration Project Update. February 23, 2011 Taylor Elementary School

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1 Donaldson Run Tributary B Stream Restoration Project Update February 23, 2011 Taylor Elementary School

2 Big picture concepts Past land use and drainage decisions have severely impacted County streams Watershed improvements and in-stream restoration efforts are both essential Urban stream corridor damage must be addressed comprehensively Stream restoration accomplishes multiple resource management objectives Neighborhood partnership is essential

3 County/Donaldson Run Civic Association Partnership 10+ year partnership Stream restoration top neighborhood priority NCAC approved Tributary B funding in December 2007; County Board 2008; DES providing additional funds Extensive County/DRCA public process: meetings, workshops, stream walks, newsletter articles, park signs, Citizen articles, and other media coverage

4 Donaldson Run watershed Donaldson Run Watershed Boundary Tributary C Tributary B Taylor School Tributary A

5 KEY PROJECT FACTS: Approved Neighborhood Conservation Program Project 1,400 linear feet to Upton street 26% impervious cover in watershed Natural channel design approach

6 Review of changes from 30% to 60% design Reducing width of channel/floodplain to reduce footprint and tree/valley impacts Limiting re-location of pathway and narrowing pathway Reducing disturbance and tree impacts below the footbridge

7 Updates from 60% design to current design level (~75%) Step pool grade control and riffle structures Analysis of hillside and storm pipe drainage inputs Water main survey Planting plan Invasive plant management

8 Step Pool Grade Control and Control stream energy Protect streambanks Provide improved stream habitat Riffle Structures

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10 Hillside drainage inputs Working with specific property owners Accommodating flow inputs in project design

11 Storm pipe drainage inputs Verifying easements/pipe conditions Incorporating needed repairs/modifications into project design

12 30 Water Main Primary Source of Supply to Lee Water Station Long-exposed pipe segments in valley identified as 30 water main and surveyed to determine location Interim work completed to protect exposed pipe Few apparent conflicts with stream restoration design except at stilling basin Small borings will be excavated to confirm pipe elevations Stream restoration design will improve protection

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14 Trees No change in tree impacts from project from 60% designs to current design One tree removed to protect water main (previously listed as a potential removal) One tree has fallen (previously listed as a removal) Project impact: 36 trees>10 diameter, 72 trees overall

15 Invasive Management & Planting Plan Goals: To restore forest structure and function To support recreational use and aesthetics

16 Invasive Management & Planting Plan Why invasive management? Displace native species Reduce wildlife habitat Alter ecosystem processes On a global basis...the two great destroyers of biodiversity are, first habitat destruction, and, second invasion by exotic species. E. O. Wilson Courtesy NPS Japanese Barberry Japanese (Berberis stiltgrass thunbergii) (Microstegium vimineum)

17 Current Forest Conditions

18 Resources Natural Resource Management Plan ments/file76445.pdf Ecological community mapping Modified urban landscape Species inventory for Zachary Taylor Park Keeping it Natural es/epo/pdffiles/keeping%20it%20natural.pdf

19 Wisteria

20 Kudzu Invasive Plants 85-95% invasive species in the shrub and ground layers invasive species present on both park and private properties 27 different species

21 Implications Invasive management considerable component of the project Project requires integrated planting and invasive plant removal 4-6 year planting and invasive plant maintenance schedule Complete removal of invasive species is likely not possible Most successful if private citizens are involved in invasive management

22 Planting Plan Site specific All plants will be native to Zachary Taylor Park Planting zones to account for habitat changes with elevation and distance from the stream. Special plantings for sensitive areas Multi-year to account for invasive control and natural forest succession

23 Zoned Planting - Example Slope Floodplain

24 Special Areas Stream Banks

25 Special Areas Bare Slopes

26 Scarlet oak Quercus coccinea Arrowwood Viburnum dentatum Bluestem goldenrod Solidago caesia

27 Pre-project Invasive Management removal of invasive shrubs outreach to homeowners During construction/planting Clean equipment Mulch or mats for trees/shrubs Seed heavily Protect deer candy Multiple planting cycles

28 Invasive Management Post-Project/Maintenance Protect trees and shrubs Focus on stream banks Target species Coordinate invasive removal and planting Timing of control will depend on plant life cycle Flexible and adaptive

29 English Ivy (Hedera helix)

30 Next Steps Continue work with property owners on hillside drainage inputs and design work for storm pipe drainage inputs Finalize planting plan and invasive plant management plan Develop construction access/staging plan Hold stakeholder advisory group meeting prior to full design completion Target design completion by end of summer Construction schedule still TBD

31 Tributary A, June 2010 For more information contact: Jason Papacosma / Christin Jolicoeur Arlington County Dept. of Environmental Services Environmental Management Bureau (703) jpapacosma@arlingtonva.us cjolicoeur@arlingtonva.us Learn more at: search Donaldson Run.