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Urban Subwatershed Restoration Manual Series UnifiedUnified StreamStream 10 Assessment:Assessment: 11 AA UserUser’s’s ManualManual Version 2.0 February 2005 Manual 10 Photo Acknowledgments Table 10: R. Frymire (vegetation at outfall) Table 10: DEM, Fort Worth, TX (suds in pool; outfall staining) Figure 25: Friends of Sligo Creek (invasive plant removal) Figure 25: South River Federation (buffer planting) Figure 26: DEM, Forth Worth, TX (sewer overflow) Table 18: Clemson University (manhole examination) Table 18: US EPA (manhole stack deterioration; debris jams) Table 18: Restonpath.com (manhole in wetland) Figure 27: Mecklenburg County, NC (sewer line repair) Figure 27: Friends of Sligo Creek (fish barrier) Figure 28: Ft. Worth DEP, TX (sewer overflow) Figure 29/30: Friends of Sligo Creek (trash pickup) Figure 31: City of Austin, TX (no dumping sign) Table 21: Ellicott City VIEW (staff in culvert) Table 27: Mark Sommerfield (algae on rock) Urban Subwatershed Restoration Manual No. 10 UNIFIED STREAM ASSESSMENT: A USER’S MANUAL Version 2.0 Prepared by: Anne Kitchell and Tom Schueler Center for Watershed Protection 8390 Main Street, 2nd Floor Ellicott City, MD 21043 www.cwp.org www.stormwatercenter.net Prepared for: Office of Water Management U.S. Environmental Protection Agency Washington, D.C. February 2005 Copyright ©2005 by the Center for Watershed Protection. Material may be quoted provided credit is given. Printed in the United States of America on recycled paper. Foreword Foreword This manual distills two decades of experience Bay Trust, Baltimore County Department of evaluating the restoration potential of urban Environmental Protection and Resource stream corridors during dozens of rapid stream Management, and the National Fish and assessments. We have attempted to assemble Wildlife Foundation for providing community our basic assessment approach into a single watershed grants that allowed us to keep on package, known as the Unified Stream testing this method in a variety of urban Assessment (USA). Over the past two years, watershed conditions. Center staff have continuously sought to refine, test the USA in our watershed practice, and it The basic Center staff team that contributed to has undergone at least four major revisions. We the development of the USA includes Ted expected that it would be further adjusted over Brown, Ken Brown, Karen Cappiella, Anne time; therefore, we are pleased to release this Kitchell, Chris Swann, Tom Schueler, manual in Version 2.0, in response to user Stephanie Sprinkle, Paul Sturm, Tiffany feedback and new resources. Wright, and Jennifer Zielinski. Special thanks to Tiffany Wright, Heather Holland, and Lauren We would like to acknowledge the Maryland Lasher for their assistance in editing, proofing Department of Natural Resources teams that, and producing this manual, and to Jessica under Ken Yetman, developed and tested the Brooks for developing the accompanying Stream Corridor Assessment Method as part of Access database. the state’s Watershed Restoration Action Strategy program. The USA builds heavily This manual was produced under a cooperative upon this method and its associated database agreement with US EPA Office of Water CP- provided by the DNR. 82981501. Thanks are extended to our EPA project officer, Robert Goo, for his patience, Thanks also to our external reviewers, who insights and flexibility during the two years it included participants at our inaugural took to produce this manual series. Watershed Restoration Institute as well as local watershed organizations, such as the Gwynns Falls Watershed Association, Jones Falls Watershed Association, South River Federation and others. Special thanks to the Chesapeake Sincerely, Anne Kitchell Center for Watershed Protection Urban Subwatershed Restoration Manual 10 i Foreword ii Urban Subwatershed Restoration Manual 10 Foreword About the Restoration Manual Series This is the tenth manual in an 11 manual series outlines a practical, step-by-step approach to that provides detailed guidance on how to repair develop, adopt and implement a subwatershed urban watersheds. The entire series of manuals plan in your community. Within each step, the was written by the Center for Watershed manual describes 32 different desktop analysis, Protection to organize the enormous amount of field assessment, and stakeholder involvement information needed to restore small urban methods used to make critical restoration watersheds into a format that can easily be management decisions. accessed by watershed groups, municipal staff, environmental consultants and other users. The The next seven manuals provide specific contents of the manuals are organized as guidance on how to identify, design, and follows. construct the seven major groups of watershed restoration practices. Each of these “practice” manuals describes the range of techniques used to implement each practice, and provides Manual 1: An Integrated detailed guidance on subwatershed assessment Approach to Restore methods to find, evaluate and rank candidate Small Urban Watersheds sites. In addition, each manual provides extensive references and links to other useful The first manual introduces the basic concepts resources and websites to design better and techniques of urban watershed restoration, restoration practices. The seven manuals are and sets forth the overall framework we use to organized as follows: evaluate subwatershed restoration potential. The manual emphasizes how past subwatershed alterations must be understood in Manual 3: Storm Water order to set realistic expectations for future Retrofit Practices restoration. Toward this end, the manual presents a simple subwatershed classification The third manual focuses on storm water system to define expected stream impacts and retrofit practices that can capture and treat restoration potential. Next, the manual defines storm water runoff before it is delivered to the seven broad groups of restoration practices, stream. The manual describes both off-site and describes where to look in the storage and on-site retrofit techniques that can subwatershed to implement them. The manual be used to remove storm water pollutants, concludes by presenting a condensed summary minimize channel erosion, and help restore of a planning approach to craft effective stream hydrology. The manual then presents subwatershed restoration plans. guidance on how to assess retrofit potential at the subwatershed level, including methods to Manual 2: Methods to conduct a retrofit inventory, assess candidate sites, screen for priority projects, and evaluate Develop Restoration Plans their expected cumulative benefit. The manual for Small Urban concludes by offering tips on retrofit design, Watersheds permitting, construction, and maintenance considerations in a series of 17 retrofit profile The second manual contains detailed guidance sheets. on how to put together an effective plan to restore urban subwatersheds. The manual Urban Subwatershed Restoration Manual 10 iii Foreword Manual 4: Urban Stream Manual 6: Discharge Repair Practices Prevention Practices The fourth manual concentrates on practices The sixth manual covers practices used to used to enhance the appearance, stability, prevent the entry of sewage and other pollutant structure, or function of urban streams. The discharges into the stream from pipes and spills. manual offers guidance on three broad The manual describes a variety of techniques to approaches to urban stream repair – stream find, fix and prevent these discharges that can cleanups, simple repairs, and more sophisticated be caused by illicit sewage connections, illicit comprehensive repair applications. The manual business connections, failing sewage lines, or emphasizes the powerful and relentless forces industrial/transport spills. The manual also at work in urban streams, which must always briefly presents desktop and field methods to be carefully evaluated in design. Next, the assess the severity of illicit discharge problems manual presents guidance on how to set in your subwatershed. Lastly, the manual appropriate restoration goals for your stream, profiles different “forensic” methods to detect and how to choose the best combination of and fix illicit discharges. Manual 6 is also stream repair practices to meet them. known as the Illicit Discharge Detection and Elimination Guidance Manual: a guidance The manual also outlines methods to assess manual for program development and stream repair potential at the subwatershed technical assessment, and is referenced as level, including basic stream reach analysis, Brown et al., 2004, throughout this manual. more detailed project investigations, and priority screenings. The manual concludes by offering Manual 7: Watershed practical advice to help design, permit, construct and maintain stream repair practices Forestry Practices in a series of more than 30 profile sheets. The seventh manual reviews subwatershed practices that can improve the quality of upland Manual 5: Riparian pervious areas, which include techniques to Management Practices reclaim land, revegetate upland areas, and restore natural area remnants. When broadly The fifth manual examines practices to restore applied, these techniques can improve the the quality of forests and wetlands within the capacity of these lands to absorb rainfall and remaining stream corridor and/or flood plain. It sustain healthy plant growth and cover. This begins by describing site preparation techniques brief manual also outlines methods to assess
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