Final Columbia Watershed Management Plan April 22 , 2009 Final Columbia Watershed Management Plan Prepared for Columbia Association 10221 Wincopin Center Columbia, MD 21044 Prepared by Mark Southerland Beth Franks Steve Harriott Tom Jones Brenda Morgan Alexi Boado Versar, Inc. 9200 Rumsey Road Suite 100 Columbia, MD 20145 and Carrie Capuco Kimi Will Capuco Consulting Services, Inc. McCormick Taylor 214 Duke of Gloucester Street 509 South Exeter Street, 4th Floor Annapolis, MD 21401 Baltimore, MD 21202 April 22, 2009 TABLE OF CONTENTS Executive Summary ..............................................................................................................................i 1. Goals and Objectives...................................................................................................................1 2. Technical Approach and Work Plan.........................................................................................5 3. Condition of the Columbia Watersheds and Priorities for Restoration.................................7 3.1 Status of Watershed Planning in Columbia.........................................................................7 3.2 Condition of Columbia Watersheds..................................................................................12 3.3 List of Phase 1 Subwatersheds..........................................................................................19 4. Phase 1 Restoration in Priority Subwatersheds .....................................................................27 4.1 Field Investigations ...........................................................................................................27 4.2 List of Retrofit Projects.....................................................................................................29 4.3 Concept Plans....................................................................................................................39 5. Early Action Projects throughout the Columbia Watersheds ..............................................63 5.1 Reforestation Opportunities ..............................................................................................63 5.2 Stormwater Management and Landscaping at CA Facilities ............................................66 5.3 Neighborhood Actions ......................................................................................................74 5.4 List of Early Action Projects.............................................................................................79 6. Stakeholder Involvement..........................................................................................................83 6.1 Stakeholder Involvement Planning ...................................................................................83 6.2 Community Stewardship Strategy.....................................................................................84 7. Recommendations for Future Actions.....................................................................................87 8. Conclusions ................................................................................................................................93 9. References ..................................................................................................................................95 Appendices A. Glossary of Watershed Terms B. Maps of the 20 Subwatersheds in CWMP Study Area, including Stream Conditions, Restoration Sites (Retrofits), and Reforestation Sites C. CWMP Interim Work Products by Task xi LIST OF TABLES Table No. Page 2-1. Work Plan for the Columbia Watershed Management Plan......................................................6 3-1. Number, name, and parent watershed of each subwatershed in the CWMP study area............7 3-2. Metrics used in comparative subwatershed assessment ..........................................................23 3-3. Problem, ecological value, and restoration opportunity score sums and weighted restoration potential score for each Columbia subwatershed ..................................................24 4-1. Potential restoration projects developed for the six priority subwatersheds ...........................31 4-2. Potential restoration sites identified using Retrofit Reconnaissance Investigations in the priority subwatersheds...................................................................................................32 4-3. Restoration sites with concept plans (Tier 1 sites) in the Lake Elkhorn subwatershed...........41 5-1. Model planting plan for native trees on 4 acres at the Columbia Association Dorsey Hall site....................................................................................................................................64 5-2. Sites investigated for reforestation opportunities in the Columbia watersheds.......................67 5-3. Summary of Neighborhood Source Assessment results and recommended community actions for Columbia, Maryland..............................................................................................75 5-4. Early action projects for the CWMP, including reforestation on CA Open Space, pollu- tion prevention at CA Facilities, and community actions in Columbia neighborhoods..........80 xii LIST OF FIGURES Figure No. Page 3-1. Number and boundaries of each subwatershed in the CWMP study area.................................8 3-2. Watershed areas within the CWMP study area expected to have an adequate water shed plan that can supplement the CWMP..............................................................................11 3-3. Biological assessment results for all sites sampled in the CWMP study area since 2000 ......13 3-4. Green infrastructure hubs and corridors and Ecologically Significant Areas identified by Maryland DNR in the CWMP study area...........................................................................15 3-5. Six priority subwatersheds selected for more intensive analysis in Phase 1 of CWMP .........25 4-1. Stream condition in the six priority subwatersheds based on Stream Corridor Assessment (SCA) data ...........................................................................................................28 4-2. Location of 116 candidate sites, 66 restoration (RRI) sites, and 18 concept plan sites in the six priority subwatersheds .............................................................................................38 4-3. Location of candidate sites, restoration (RRI) sites, and concept plan sites in the Lake Elkhorn subwatershed .............................................................................................................44 4-4. Concept plan for LE-RRI-001: New Pond off Brush Run Road.............................................45 4-5. Concept plan for LE-RRI-002: LID at end of Deep Pasture...................................................46 4-6. Concept plan for LE-RRI-003: LID at end of Mendenhall Court ...........................................47 4-7. Concept Plan for LE-RRI-011: SWM Pond Retrofit of existing pond off Emerson’s Reach.......................................................................................................................................48 4-8. Concept Plan for LE-RRI-012: LID off Cloud Leap Court.....................................................49 4-9. Concept Plan for LE-RRI-013: LID corner of Tamar Drive and Lambskin Lane ..................50 4-10. Concept Plan for LE-RRI-015: Stream Restoration off Queen Maria Court and Blade Green Court...................................................................................................................51 4-11. Concept Plan for LE-RRI-019: Stream Bank Stabilization at end of Spinning Seed..............52 4-12. Concept Plan for LE-RRI-020: Stream Stabilization at corner of Dobbin Road and Mendenhall Court....................................................................................................................53 4-13. Concept Plan for LE-RRI-024: LID at end of Windbell Lane ................................................54 4-14. Concept Plan for LE-RRI-026: LID at corner of Smooth Path and Honeyladen....................55 4-15. Concept Plan for LE-RRI-501: LID behind Celebration Church............................................56 4-16. Concept Plan for LE-RRI-502: LID at Dobbin, behind Playwide Kids.................................57 4-17. Concept Plan for LE-RRI-503: LID at Dobbin, in front of Playwise Kids.............................58 4-18. Concept Plan for LE-RRI-504: LID near Owen Brown YMCA.............................................59 4-19. Concept Plan for LE-RRI-505: LID along Homespun Drive.................................................60 4-20. Concept Plan for LE-RRI-506: Stream Restoration off Garland Way, outfalls into 507........61 4-21. Concept Plan for LE-RRI-507: Stream Restoration off Bugledrum .......................................62 5-1. Enhanced aerial photograph depicting two potential forest planting areas covering 4 acres (outlined in red) at the Columbia Association Dorsey Hall site..............................................65 xiii xiv 1. Goals and Objectives The Columbia Association (CA) is developing a Columbia Watershed Management Plan (CWMP or Plan) that outlines a long-term, far-reaching strategy to protect and restore the Little and Middle Patuxent Rivers and adjacent waters. The CWMP will support ongoing efforts and provide a sustainable pathway to effectively manage these Columbia watersheds going forward. Ultimate suc- cess in meeting