Technical University of Dresden Faculty of Environmental Science Development of a GIS and model-based method for optimizing the selection of locations for drinking water extraction by means of riverbank filtration A dissertation in partial fulfillment of the requirements for the degree of Doctor rerum naturalium (Dr. rer. nat.) Presented by: Yan Zhou born on 22. November 1989 in Zhejiang, China (Defense date: 22.09.2020) Reviewer: Prof. Dr. Rudolf Liedl Technical University of Dresden, Institute of Groundwater Management Prof. Dr. Olaf Kolditz Helmholtz-Centre for Environmental Research, Department Environmental Informatics Prof. Dr. Holger Weiß Helmholtz-Centre for Environmental Research, Department Environmental Informatics Übereinstimmungserklärung Die Übereinstimmung dieses Exemplars mit dem Original der Dissertation zum Thema: “Development of a GIS and model-based method for optimizing the selection of locations for drinking water extraction by means of riverbank filtration” wird hiermit bestätigt. Ort, Datum Unterschrift (Vorname Name) Abstract The lack of safe drinking water worldwide has drawn the attention of decision makers to riverbank filtration (RBF) for its many advantages in purifying surface water. This study provides an overview of the hydrogeologic, fluvial, and environmental influences on the performance of RBF systems and aims to develop a model for RBF site selection. Using multi-attribute utility theory (MAUT), this study structured the RBF siting problem and assessed a multiplicative utility function for the decision maker. In a case study, geostatistical methods were used to acquire the necessary data and geographic information systems (GIS) were used to screen sites suitable for RBF implementation. Those suitable sites were then evaluated and ranked using the multi-attribute utility model. The result showed that sites can be identified as most preferred among the selected suitable sites based on their expected utility values. This study definitively answers the question regarding the capability of MAUT in RBF site selection. Further studies are needed to verify the influences of the attributes on the performance of RBF systems. iii Zusammenfassung Der weltweite Mangel an sauberem Trinkwasser hat die Entscheidungsträger auf die Uferfiltration (RBF) aufmerksam werden lassen, die vielfältige Vorteile bei der Reinigung von Oberflächenwasser bietet. Diese Studie bietet einen Überblick über die hydrogeologischen, fluvialen und umweltrelevanten Einflüsse auf die Leistung von RBF- Systemen und zielt darauf ab, ein Modell für die Auswahl von Standorten zur Wassergewinnung mittels Uferfiltration zu entwickeln. Unter Verwendung der multiattributiven Nutzwertanalyse (MAUT) strukturiert diese Studie das Problem der Standortauswahl zur Wassergewinnung mittels Uferfiltration und bewertet eine multiplikative Nutzenfunktion für den Entscheidungsträger. In einer Fallstudie werden geostatistische Methoden zur Erfassung der erforderlichen Daten und geografische Informationssysteme (GIS) zur Auswahl von Standorten verwendet, die für die Implementierung der Uferfiltration geeignet sind. Diese geeignete Standorte werden dann unter Verwendung des Nutzwertemodell bewertet und eingestuft. Das Ergebnis zeigt, dass die am besten geeigneten Standorte anhand ihrer erwarteten Nutzwerte unter die ausgewählte Standorten identifiziert werden können. Diese Studie beantwortet definitiv die Frage nach der Eignung von MAUT bei der Standortauswahl zur Wassergewinnung mittels Uferfiltration. Weitere Studien sind erforderlich, um den Einfluss der Attribute auf die Leistung von RBF-Systemen zu überprüfen. iv Acknowledgments I wish to express my sincere appreciation to my committee, Professor Rudolf Liedl, Professor Olaf Kolditz, and Professor Holger Weiß, who convincingly guided and encouraged me to be professional and do the right thing even when the road got tough. Without their persistent help, the goal of this project would not have been realized. I wish to show my deepest gratitude to my advisor, Professor Marc Walther, for his consistent support, guidance, constructive criticism and patience. The completion of my thesis would not have been possible without the support and nurturing by him. I am extremely grateful to Professor Thomas Grischek, Jürgen Schubert, Dr. Mick Wu, Professor Wibhu Kutanan, Dr. Yiwen Zhan, and Dr. Songcan Chen, who gave me valuable advice, invaluable experience, and profound belief in my work. Many thanks to Holger Weiß, Marc Walther, and Wibhu Kutanan for reviewing the thesis. The China Scholarship Council (CSC), the Department of Environmental Informatics of the Helmholtz Centre for Environmental Research (UFZ), and the Helmholtz Interdisciplinary GRADuate School for Environmental Research (HIGRADE) are truly appreciated. Without their support and funding, this project could not have reached its goal. I would like to extend my sincere thanks to colleagues at Jilin University and Tongji University, especially Professor Xiaosi Su, Professor Yalei Zhang, Dr. Xinqiang Du, Dr. Geng Cui, Hexuan Zhang, and Dr. Yiming Su, for their assistance with the collection of my data. Also, thanks should go to the colleagues of the Department of Environmental Informatics and the entire team of former department Groundwater Remediation at UFZ, especially Ralf Trabitzsch, Dr. Erik Nixdorf, and Dr. Wenqing Wang, who never wavered in their support. Special thanks to Eva Joanna Koper and the whole staff of the Graduate School HIGRADE for their relentless support and helpful advice during this time. I would like to recognize the help that I received from Dr. Zhiyong Song and Sarah Knechtel, who extended a great amount of assistance in preparing the maps. I gratefully acknowledge the assistance of the staff of the UFZ library, Jingzheng Zhang, Jürgen Schubert, Dr. Frank Thomas Lange, Thomas Grischek, Dr. Bin Hu, Professor Ralph L. Keeney, and numerous people, thank you for helping me in finding the sources for my thesis. Finally, I would like to thank my family and friends for supporting me during the compilation of this thesis. Especially, I am grateful to Jiayan Gao for her patience and support in many ways. v Table of Contents Abstract .............................................................................................................................. iii Zusammenfassung.............................................................................................................. iv Acknowledgments................................................................................................................v Table of Contents ............................................................................................................... vi List of Tables ................................................................................................................... viii List of Figures ......................................................................................................................x Definition of terms ........................................................................................................... xiii 1. Abbreviations ........................................................................................... xiii 2. Symbols.................................................................................................... xiii Part I Introduction ................................................................................................................1 1. Introduction ..................................................................................................2 2. Statement of purpose....................................................................................2 3. Research questions .......................................................................................3 4. Overview of methodology ...........................................................................3 5. Organization of the dissertation ...................................................................3 Part II Fundamentals and Literature Review .......................................................................5 1. The definition of bank filtration ...................................................................6 2. The Significance of RBF .............................................................................7 2.1 RBF in drinking water supply ..........................................................7 2.2 Benefits of RBF for China .............................................................14 3. RBF Site Selection .....................................................................................19 3.1 RBF site selection model ...............................................................20 3.2 Definition of successful RBF sites .................................................24 4. Factors Affecting RBF Site Selection ........................................................26 4.1 River hydrology/hydraulics ...........................................................27 4.2 Geology ..........................................................................................28 4.3 Land cover .....................................................................................36 4.4 Well field location..........................................................................36 4.5 Water quality ..................................................................................37 4.6 Aquifer properties ..........................................................................38 4.7 Distance