Herring Run Watershed Stream Assessment and Restoration Concept Plan Final Report July 2004 Herring Run Watershed Stream Assessment and Restoration Concept Plan Final Report July 2 004 Prepared for: City of Baltimore Prepared by: A. Morton Thomas & Associates, Inc. Biohabitats, Inc. 12750 Twinbrook Parkway, Suite 200 15 West Aylesbury Road Rockville, MD 20852 Timonium, MD 21093 Herring Run Watershed Stream Assessment and Restoration Concept Plan TABLE OF CONTENTS 1.0 INTRODUCTION................................................................................................. 1 1.1 BACKGROUND AND PROBLEM STATEMENT ........................................................................ 1 1.2 PROJECT GOALS AND SCOPE OF REPORT ............................................................................ 1 1.3 LOCATION OF STUDY AREA AND WATERSHED CHARACTERIZATION.................................. 2 1.4 ANTHROPOGENIC IMPACTS TO STREAMS ............................................................................ 4 2.0 METHODS ............................................................................................................ 6 2.1 CRUISED REACH ASSESSMENT ........................................................................................... 6 2.2 REACH RANKING ................................................................................................................ 9 2.2.1 Channel Stability Parameters.............................................................................................. 13 2.2.2 Habitat Parameters ............................................................................................................. 16 3.0 FIELD RESULTS AND RANKING ................................................................. 20 3.1 CRUISED REACH ASSESSMENT ......................................................................................... 20 3.2 REACH RANKING .............................................................................................................. 20 3.3 APPLICATION OF REACH RANKINGS ................................................................................. 21 4.0 STREAM RESTORATION TECHNIQUES ................................................... 25 4.1 OPPORTUNITIES AND CONSTRAINTS ................................................................................. 25 4.2 SPECIFIC RESTORATION STRATEGIES................................................................................ 27 4.2.1 Stabilize Banks Non-Structurally......................................................................................... 27 4.2.2 Stabilize Banks Structurally ................................................................................................ 28 4.2.3 Stabilize Channel Structurally............................................................................................. 29 4.2.4 Realign & Relocate Channel ............................................................................................... 30 4.2.5 Enhance Riparian Areas...................................................................................................... 31 4.2.6 Remove Channel Impediments............................................................................................. 33 4.2.7 Maintain Infrastructure....................................................................................................... 34 4.2.8 Install Trash Rack ............................................................................................................... 34 4.3 LAND MANAGEMENT STRATEGIES ................................................................................... 35 4.3.1 Preservation of Existing Forested Areas............................................................................. 35 4.3.2 Reduction of Impervious Surfaces ....................................................................................... 36 4.3.3 Appropriate Road and Culvert Maintenance ...................................................................... 37 4.3.4 Public Education ................................................................................................................. 38 5.0 REACH RESTORATION CONCEPTS........................................................... 39 Biohabitats, Inc. © •INSPIRING ECOLOGICAL STEWARDSHIP• Herring Run Watershed Stream Assessment and Restoration Concept Plan 5.1 RESTORATION CONCEPTS FOR REACH O, BIDDISON RUN................................................. 39 5.2 RESTORATION CONCEPTS FOR REACH P, BIDDISON RUN.................................................. 41 5.3 RESTORATION CONCEPTS FOR REACH T, MOORES RUN ................................................... 44 5.4 RESTORATION CONCEPTS FOR REACH U, MOORES RUN................................................... 46 5.5 COST ESTIMATES OF RESTORATION CONCEPTS ................................................................ 48 6.0 REFERENCES.................................................................................................... 50 Biohabitats, Inc. © •INSPIRING ECOLOGICAL STEWARDSHIP• Herring Run Watershed Stream Assessment and Restoration Concept Plan LIST OF TABLES TABLE 1.0 LENGTHS OF KEY STREAM REACHES ..................................................................................... 4 TABLE 2.0 PRIMARY FACTORS USED IN THE CHANNEL STABILITY RANKING ....................................... 11 TABLE 2.1 PRIMARY FACTORS USED IN THE HABITAT RANKING .......................................................... 12 TABLE 3.0 RESULTS OF CHANNEL STABILITY, HABITAT, AND TOTAL RANKING ................................... 21 LIST OF FIGURES FIGURE 1.0 LOCATION OF HERRING RUN WATERSHED WITH REACH BREAKS.......................................... 3 FIGURE 3.0 PRIORITY FOR CHANNEL STABILITY RESTORATION ............................................................. 22 FIGURE 3.1 PRIORITY FOR HABITAT RESTORATION ................................................................................ 23 FIGURE 3.2 PRIORITY FOR RESTORATION (CHANNEL STABILITY AND HABITAT).................................... 24 APPENDICES APPENDIX A CRUISED REACH DATA COLLECTION SHEETS APPENDIX B CRUISED REACH DATA SUMMARY AND BEHI RESULTS APPENDIX C REACH RANKING SYSTEM APPENDIX D REACH O RESTORATION CONCEPT DESIGN APPENDIX E REACH P RESTORATION CONCEPT DESIGN APPENDIX F REACH T RESTORATION CONCEPT DESIGN APPENDIX G REACH U RESTORATION CONCEPT DESIGN APPENDIX H PHOTOGRAPHS OF PROBLEM AREAS ALONG REACHES O, P, T, AND U APPENDIX I PRELIMINARY COST ESTIMATE FOR CONCEPT DESIGNS Biohabitats, Inc. © •INSPIRING ECOLOGICAL STEWARDSHIP• Herring Run Watershed Stream Assessment and Restoration Concept Plan 1.0 INTRODUCTION 1.1 BACKGROUND AND PROBLEM STATEMENT In February of 2003, the City of Baltimore began an assessment of the mainstem channel and tributaries of the Herring Run watershed within the City limits. This project, the Herring Run Watershed Stream Assessment and Restoration Concept Plan, called for a geomorphologic survey of approximately 18.4 miles of streams to identify and assess existing conditions, prioritize reaches for restoration, and prescribe specific approaches for several priority reaches. The Herring Run watershed is under constant pressure from urban influences, which threaten existing physical conditions and habitat values of the creek. Compared with streams in less densely populated rural areas of Maryland, much of the stream is in poor physical condition. Many portions of Herring Run are undergoing changes with adverse consequences to the watershed at large. These problems are driven by encroaching urban infrastructure, poor riparian buffers, and local bank erosion. 1.2 PROJECT GOALS AND SCOPE OF REPORT It is the intent of this Stream Assessment and Restoration Concept Plan to provide some general approaches to both 1) protecting existing stream and riparian areas and 2) ameliorating those reaches that show the most degraded conditions. Stable, healthy portions of the creek are critical for preservation given their natural tolerance to flood effects, resilience against bank erosion, and high habitat value. Furthermore, maintaining these conditions ultimately maintains good water quality conditions in the Herring Run watershed and the Chesapeake Bay itself. Of equal importance is improving those areas that pose the greatest water quality problems, thereby preventing additional deleterious channel adjustments and management costs down the road. Specifically, the Herring Run Stream Assessment and Restoration Concept Plan was developed with the following objectives in mind: Biohabitats, Inc. © •INSPIRING ECOLOGICAL STEWARDSHIP• 1 Herring Run Watershed Stream Assessment and Restoration Concept Plan • To conduct a thorough “fluvial audit” of the stream network to identify and assess existing geomorphic conditions and identify problem areas on a relative basis. • To develop stream bank stabilization and riparian corridor recommendations that would improve physical and habitat conditions in Herring Run and decrease delivery of fine sediment to Herring Run and ultimately the Chesapeake Bay. • To produce GIS coverages summarizing existing conditions to inform and/or guide future restoration planning in a consistent format. The Restoration Concept Plan followed several stages of development. First, existing conditions were qualitatively and systematically documented by Biohabitats scientists, who walked the approximately 18 miles of the Herring Run drainage network within the City limits. Next, the information was synthesized to rank problematic