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Bioretention: Evaluating Their Effectiveness for Improving Water Quality in New England Urban Environments Mary Dehais University of Massachusetts Amherst

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Bioretention: Evaluating Their Effectiveness for Improving Water Quality in New England Urban Environments Mary Dehais University of Massachusetts Amherst University of Massachusetts Amherst ScholarWorks@UMass Amherst Masters Theses 1911 - February 2014 2011 Bioretention: Evaluating their Effectiveness for Improving Water Quality in New England Urban Environments Mary Dehais University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/theses Part of the Civil and Environmental Engineering Commons, Environmental Design Commons, Environmental Sciences Commons, Forest Management Commons, Hydrology Commons, Landscape Architecture Commons, Land Use Law Commons, Soil Science Commons, and the Urban, Community and Regional Planning Commons Dehais, Mary, "Bioretention: Evaluating their Effectiveness for Improving Water Quality in New England Urban Environments" (2011). Masters Theses 1911 - February 2014. 595. Retrieved from https://scholarworks.umass.edu/theses/595 This thesis is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Masters Theses 1911 - February 2014 by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. BIORETENTION: EVALUATING THEIR EFFECTIVENESS FOR IMPROVING WATER QUALITY IN NEW ENGLAND URBAN ENVIRONMENTS A Thesis Presented by MARY F. DEHAIS Submitted to the Graduate School of the University of Massachusetts Amherst in partial fulfillment of the requirements for the degree of MASTER OF LANDSCAPE ARCHITECTURE May 2011 Department of Landscape Architecture and Regional Planning BIORETENTION: EVALUATING THEIR EFFECTIVENESS FOR IMPROVING WATER QUALITY IN NEW ENGLAND URBAN ENVIRONMENTS A Thesis Presented By MARY F. DEHAIS Approved as to style and content by: John F. Ahern, Chair Paul K. Barten, Member Mi-Hyun Park, Member Elizabeth Brabec, Department Head Department of Landscape Architecture and Regional Planning ACKNOWLEDGMENTS I would like to acknowledge all the assistance I received from my thesis committee as this thesis would not have been possible without their exceptional guidance, knowledge and insight. I would like to express my deepest and sincere gratitude to Jack Ahern for his personal interest in the subject of stormwater management, my academic and professional development, and his intensity and desire to push me farther with my work. Thanks are also due to the members of my committee, Paul Barten and Mi-Hyun Park, for their support, patience and insightful contributions to this manuscript and in helping me to cross the boundaries to environmental science and engineering. I will forever be grateful to all of you. I would also like to extend my gratitude to the many people who assisted me with this project. Thanks to Tom Tavella from Fuss & O’Neill for giving me a seed of an idea, one that launched me on a momentous journey, and from which I learned a great deal that will continue to inform me professionally as I move into the next phase of my career. Special thanks to Jack Clausen from the University of Connecticut, Department of Natural Resources and the Environment, for his assistance and expert guidance on stormwater monitoring. A special thank you to my family, friends and fellow classmates whose support and friendship truly helped me to stay focused on this project and provided me with the necessary encouragement along the way to continue moving forward. A loving thanks to my husband, John and daughter, Samantha for their unending support, encouragement and affection that carried me through. Without their support, this would not have been possible. iii ABSTRACT BIORETENTION: EVALUATING THEIR EFFECTIVENESS FOR IMPROVING WATER QUALITY IN NEW ENGLAND URBAN ENVIRONMENTS MAY 2011 MARY F. DEHAIS, B.S. CENTRAL CONNECTICUT STATE UNIVERSITY M.L.A. UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Jack Ahern Nonpoint source (NPS) pollution has been identified by the USEPA (2005) as one of the leading causes of water quality problems in the United States. Bioretention has become one of the more frequently used stormwater management practices for addressing NPS pollution in urbanized watersheds in New England. Yet despite increased acceptance, bioretention is not widely practiced. This study explores and evaluates the efficacy of bioretention for protecting urban water quality. This research found that numerous monitoring methods are used by researchers and industry experts to assess the effectiveness of stormwater best management practices (BMPs) and low impact development (LID) practices, including bioretention. The two most common methods for analyzing and evaluating water quality data are pollutant removal efficiency and effluent quality. While effluent quality data is useful for characterizing classes of BMP treatment performance on a statistical basis, pollutant removal efficiency is more representative of the actual pollutant load being reduced by the stormwater treatment practice over time, and is used in Total Maximum Daily Load (TMDL) assessments. However, despite this difference, monitoring is still arguably the best method for determining the effectiveness of stormwater treatment practices. iv Monitoring of bioretention performance results is needed to inform improvements to design standards and guidance to aid state and local municipalities in the proper selection of bioretention/stormwater controls. This study advocates for instituting fine- scale, “safe-to-fail” design experiments as part of an adaptive management process that is used to advance bioretention design guidance and future applications of monitoring practice(s) that target reduction of pollutants in downstream receiving waterbodies. This innovative approach could result in increased use of bioretention in New England urban environments. v TABLE OF CONTENTS Page ACKNOWLEDGMENTS ................................................................................................. iii ABSTRACT ....................................................................................................................... iv LIST OF TABLES ........................................................................................................... viii LIST OF FIGURES .............................................................................................................x CHAPTER 1. THE STATE OF WATER QUALITY ..........................................................................1 Introduction ..........................................................................................................1 The Clean Water Act ...............................................................................................4 Governance of State Stormwater Programs .............................................................9 Commonwealth of Massachusetts..............................................................11 State of Connecticut ...................................................................................12 Research Goals and Objectives ..............................................................................14 Summary and Chapter Outline ...............................................................................15 2. LITERATURE REVIEW ............................................................................................17 Introduction ........................................................................................................17 Stormwater Management Practices ........................................................................19 Low Impact Development......................................................................................24 Bioretention ........................................................................................................27 Rain Gardens ............................................................................................35 Performance Monitoring and Assessment .............................................................38 Stormwater Monitoring Parameters ...........................................................39 Water Quality Monitoring..........................................................................41 Data Analysis ............................................................................................43 Mathematical Stormwater Models .............................................................45 Experimental Field Studies ........................................................................47 Challenges of Cold Weather ......................................................................52 Summary ................................................................................................................56 vi 3. A METHOD FOR ASSESSING THE EFFECTIVENESS OF BIORETENTION TO IMPROVE WATER QUALITY ...........................................................................58 Overview of the Methods .......................................................................................58 4. APPLICATION ...........................................................................................................63 Monitoring Protocols .............................................................................................63 Pollutant Removal Performance ............................................................................73 Natural Processes Affecting Pollutant Removal ........................................73 International Stormwater BMP Database ..................................................80 National Pollutant Removal Performance Database ..................................88 LID Monitoring Case Studies
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