URBAN AND REGIONAL PLANNING Masters Thesis Assignment

Green Infrastructure in Amsterdam: an analysis of current implementation, the potential benefits and the context-specific barriers affecting expansion of networks

Prepared for: Dr Mendel Giezen Graduate School of Social Sciences University of Amsterdam The Netherlands

Prepared by: Christi Vosloo 11129042

Submission Date: 20 June 2016 i

Plagiarism Declaration i) I know that plagiarism is wrong. Plagiarism is to use another’s work and pretend that it is one’s own, ii) I have used the Harvard-UVA Convention for citation and referencing. Each contribution to, and quotation in, this report from the work(s) of other people has been attributed, and has been cited and referenced, iii) This report is my own work, iv) I have not allowed, and will not allow, anyone to copy my work with the intention of passing it off as his or her own work, and v) I acknowledge that copying someone else’s work, or part of it, is wrong, and declare that this is my own work.

Name Student Number Date Signature Christi Katherine Vosloo 11129042 20/06/2016

[Cover Image Source: Rooftop Revolutions, 2016]

Masters Thesis: Green Infrastructure in Amsterdam Plagiarism Declaration ii

Masters Thesis: Green Infrastructure in Amsterdam Plagiarism Declaration iii

Acknowledgements

I would like to thank my mother and my father for allowing me the opportunity to receive an education and for seeing the value it holds for my future and fulfilment. Their support and encouragement throughout these past five years has meant everything to me and I am forever grateful. I would like to thank my brother and sister for standing by my side and for always being my greatest cheerleaders. I am grateful to my colleagues who made this international experience a memory that will last a lifetime. I would like to thank my supervisor Professor Mendel Giezen for his constant support and expertise throughout this process, thesis writing and researching takes an extended amount of time and without his guidance it would not have been possible. I would like to thank my masters lecturers Professor Willem Salet, Beatriz Pineda Rivella, Professor Federico Savini, Professor Tuna Tasan Kok, Professor Luca Bertolini and Professor Marco te Brömmelstroet for inspiring me to delve deeper, think critically and aim higher.

For my supportive and loving parents

Masters Thesis: Green Infrastructure in Amsterdam Acknowledgements iv

Abstract

In an urbanizing world, cities such as Amsterdam need to undergo a transformation to become climate adapted, prepared and robust. This transition is needed to address surface water runoff challenges caused by the effects of climate of change, increased frequency of extreme weather events and changing seasonality. In the city of Amsterdam permeable green space and permeable green infrastructure is limited despite a green roof subsidy provided by the government. This research investigates the current implementation, the potential green infrastructure holds in improving surface water runoff in the city and the current policy measures and policy instruments. The barriers to implementation and expansion of green infrastructure in existing buildings in Amsterdam are investigated, with the hope to offer potential solutions and recommendations for the city of Amsterdam. This study focuses on the case study of Amsterdam by conducting two focused literature reviews and consulting experts from Waternet, Amsterdam Rainproof, De Dak Dokters, Deltares and Utrecht University. Citizens of Amsterdam were interviewed to ascertain their level of awareness and assess their perception of green infrastructure. Each expert respondent ranked the barriers in order of importance using Q-Methodology, with this mixed method approach offering a level of comprehensiveness that simply one approach may not attain. The literature review and analysis indicated a clear under realization of permeable green infrastructures in Amsterdam with 14,9% of the study area consisting of permeable green space. Analyses by Rooftop Solutions indicated that less than 1% of rooftops in Amsterdam are green. The most important barriers as identified by the experts included the cost of installation and maintenance which remains twice as costly even when including the green roof subsidy, the lack of ‘know-how’ of citizens, the lack of policy, added technical measures needed to ensure safe installation, a lack of accurate data which is still needed to create a convincing business case and the soft benefits that are difficult to monetize, resulting in subjective decisions on a case by case basis. From the combined data analysis I concluded that one highly important barrier was a mismatch between policy instruments and implementation barriers in Amsterdam. The only currently implemented policy instrument is a green roof subsidy which only addresses the financial question while the barriers identified are a variety of financial, social and institutional factors. This mismatch results in important barriers remaining unchallenged. The citizen interviews indicated an extreme lack of awareness and ‘know-how’ with regards to green roofs in Amsterdam despite the positive attitude towards their presence. I recommend that through strong political decision-making and support, effective policy could be implemented to ensure that that new developments will include a green infrastructure measure. Long-term educational school programs could help lead to generational change and encourage the youth to start their own initiatives and become involved. Deregulation of complex green roof regulations is necessary to ensure that there are fewer unnecessary and deterring spatial requirements. A more comprehensive approach is important

Masters Thesis: Green Infrastructure in Amsterdam Abstract v in ensuring long-term climate adaption, with focus on purely rainproof measures possibly neglecting other important areas. I advocate for more green roof research quantifying the positive benefits and providing scientific data convincing for the business case.

Masters Thesis: Green Infrastructure in Amsterdam Abstract vi

Table of Contents

1. Introduction 1-1 1.1 Problem Statement 1-1 1.2 Research Goal and Objectives 1-2 1.3 Research Questions 1-2 1.4 Research Strategy 1-2 1.5 Study Outline 1-3

2. Theoretical Chapter 2-1 2.1 Urbanization in Relation to Surface Water Runoff 2-1 2.2 Green Infrastructure 2-1 2.3 Surface Water Runoff 2-4 2.4 Policy Instruments 2-4 2.4.1 The Choice Versus Resource Approach 2-4 2.5 Implementation Theory 2-6 2.5.1 Top-Down Implementation 2-7 2.5.2 Bottom-Up Implementation 2-8

3. Barriers of Green Infrastructure Implementation Explained 3-11 3.1 Social Barriers 3-11 3.2 Institutional Barriers 3-12 3.3 Economic Barriers 3-12 3.4 Physical Barriers 3-12 3.5 Educational Barriers 3-13 3.6 Conceptual Model 3-13

4. Research Design 4-1 4.1 Methodology 4-1 4.2 Case Selection 4-1 4.3 Focused Literature Review 4-1 4.4 Semi-structured Interviews 4-2 4.4.1 Selection of Respondents 4-2 4.4.2 Transcribing, Coding and Analysing 4-2 4.5 Q- Methodology 4-2 4.5.1 Design Concourse 4-3

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4.5.2 Selecting Respondents 4-3 4.5.3 Q-Sorting 4-3 4.5.4 Data Analysis and Interpretation 4-4 4.6 Operationalization 4-4 4.7 Strengths of Mixed Methods 4-4 4.8 Limitations of Methods 4-5

5. The Potential of Green Infrastructure in Amsterdam 5-1 5.1 Current Organizations and Companies 5-1 5.1.1 Waternet 5-2 5.1.2 Amsterdam Rainproof 5-2 5.1.3 De Dak Dokters 5-3 5.1.4 De Groene Grachten 5-3 5.1.5 De Gezonde Stad 5-3 5.1.6 Rooftop Revolution 5-4 5.2 Current Policies & Incentives 5-4 5.2.1 Green Roof Subsidy 5-4 5.2.2 Tax Scheme 5-5 5.2.3 Insurance Fee Reduction 5-5 5.2.4 Lack of Policy 5-5 5.3 Quantifying the Current Situation 5-6 5.4 Quantifying Potential Area Available 5-7 5.5 Benefits 5-8 5.5.1 Water 5-8 5.5.2 Habitat and Biodiversity 5-10 5.5.3 Air Quality 5-12 5.5.4 Urban Heat Island Effect 5-13 5.5.5 Energy Efficiency 5-14

6. Results: Expert and Citizen Perception of the Current Situation 6-1 6.1 Expert Opinion of the Green Infrastructure Potential in Amsterdam 6-2 6.1.1 Potential 6-2 6.2 Expert Perception And Importance of Greatest Challenges Explained 6-5 6.2.1 Social Barriers 6-5 6.2.2 Institutional Barriers 6-6 6.2.3 Economic Barriers 6-8 6.2.4 Physical Barriers 6-9 6.3 Critiques of the Green Roof Subsidy 6-10 6.3.1 Does not Ensure Quality 6-10

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6.3.2 Benefits Water Authority 6-10 6.3.3 Mobilizes Non-Target Group 6-11 6.3.4 Too Complex 6-11 6.4 Potential Solutions 6-11 6.4.1 The Right Dialogue 6-11 6.4.2 Deregulation 6-11 6.4.3 Small Scale Solution Measurement System 6-12 6.4.4 An Improved Subsidization System 6-12 6.4.5 Showcase Projects 6-12 6.4.6 Crowd-Funding Start Up: Rooftop Revolutions 6-13 6.4.7 Certifications 6-13 6.4.8 Ideological Shift with More Evidence 6-13 6.4.9 Focus on Intensive Roofs 6-13 6.4.10 The Right Marketing 6-13 6.4.11 Cheaper Technology 6-14 6.4.12 Start with Younger Generations 6-14 6.4.13 Changing Infrastructure at the Right Moment 6-14 6.4.14 Mainstreaming 6-15 6.4.15 Insurance Scheme and Tax Scheme 6-15 6.4.16 Policy 6-16 6.5 Citizen Perspectives 6-16 6.5.1 Perception of Green Roofs 6-16 6.5.2 Public Awareness 6-16 6.5.3 Water Issues 6-17 6.5.4 Amsterdam as a Green City 6-17

7. Discussion 7-1 7.1 Main Findings 7-1 7.1.1 Great Under Realization of Permeable Green Infrastructures in Amsterdam 7-1 7.1.2 Greatest Barriers in Amsterdam 7-1 7.1.3 Lack of Existing Policy 7-1 7.1.4 Mismatch Between Policy Instruments and Barriers 7-2 7.1.5 Extreme Lack of Citizen Awareness 7-2 7.2 Results in Relation to Theory 7-3 7.2.1 Top-Down Implementation 7-3 7.2.2 Bottom-up Implementation 7-4 7.2.3 In Relation to Policy Instruments 7-4 7.2.4 The Choice Versus Resource Approach 7-5 7.3 Limitations of the Study 7-5 7.4 Scientific Relevance 7-6

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7.5 Opportunities for Further Research 7-6

8. Concluding Remarks 8-1

9. Recommendations 9-1 9.1 Political Support and Policy 9-1 9.2 Long-term School Programmes 9-1 9.3 Deregulation 9-1 9.4 Comprehensive Approach 9-2 9.5 More Research 9-2

References 1

Appendix A | Semi-Structured Interviews A1

Appendix B | Q-Methodology B1

Appendix C | Table of Calculations C1

Appendix D | Images D1

Masters Thesis: Green Infrastructure in Amsterdam Table of Contents x

List of Illustrations

List of Figures Figure 2-1: Schematic illustration of Public Policy Choices and the Position of Policy Instruments in Biased Options ...... 2-5 Figure 3-1: Conceptual Model illustrating relationship between policy instruments, barriers and the outcome of implementation in green infrastructures in Amsterdam...... 3-14 Figure 5-1: Map of the study area of in Amsterdam, The Netherlands...... 5-1

List of Tables Table 2-1: Examples of Policy Instruments in Amsterdam and the given assumptions ...... 2-6 Table 2-2: Comparison between Top-down and Bottom-Up Approaches ...... 2-10 Table 4-1: Approximate calculations of the current permeable green areas present in Amsterdam (km2) ...... 5-7 Table 6-1: Q-Methodology results indicating the greatest and least important barriers for each expert respondent...... 6-1 Table 6-2: A Summary of the barriers identified for implementing green roofs in the city of Amsterdam ...... 6-2

Masters Thesis: Green Infrastructure in Amsterdam List of Illustrations xi

List of Abbreviations

GI Green Infrastructure

NO2 Nitrogen dioxide PM Particulate Matter UFORE Urban Forest Effects UHI Urban Heat Island WHO World Health Organization

Masters Thesis: Green Infrastructure in Amsterdam List of Abbreviations 1-1

1. Introduction

In developed countries the level of urbanization is still increasing and expected to reach 83% by 2030 (United Nations, 2002). Urbanization and development results in increasing replacement of croplands, grassland and open soil by impervious surfaces such as roads and paving, intensifying storm water runoff and water flows (Stone, 2004). Urbanization affects the urban hydrological system resulting in a highly fluctuating amount of surface water runoff (White, 2002), while climate change can potentially further increase these fluctuations (Mentens et al. 2005). Tools for reducing runoff include storage reservoirs, ponds and green areas where water can infiltrate and evaporate (White, 2002). Scholars call for a rethinking of the urban hydrological system to ensure that it plays a positive role in the water cycle, by using green infrastructures to create a green urban fabric (White, 2002; Mentens et al. 2005). Unfortunately in cities, land prices are high and investors and developers are concerned with earning profit, and less so with greening the city. This creates an opportunity for green infrastructures, green walls and green roofs in previously unused space. Green infrastructures can contribute to (1) delaying the initial time of runoff due to the infiltration of the water, (2) reducing total surface runoff by absorbing water, (3) potentially mitigating the urban heat island effect, and (4) reducing the cost of heating and cooling in buildings (Mentens et al. 2005). Amsterdam is a canalized city with many cobbled streets, canal water-ways, historic buildings and has great potential for further greening and expanding of current green infrastructures. Amsterdam, and the Netherlands which are low-lying areas, have a very rich history with water and its ties to the natural landscape. Due to the nature of the Netherlands and Amsterdam, more attempts should be made to focus on the potential green infrastructures can possess in terms of contributing to altering and delaying surface water flows in the city. Despite the provision of a green roof subsidy from government, the full potential of green infrastructure in Amsterdam is not being realized due to barriers of implementation and expansion. With increases in extreme weather events and precipitation, this becomes an issue of increasing urgency. This study aims to assess the potential of green infrastructures in the city of Amsterdam on surface water runoff, as well as to evaluate the barriers, policy instruments and challenges to implementation and expansion of green infrastructure networks in the city.

1.1 Problem Statement In the current decade of climate change, there is potential for increased rainfall events, severe weather and alterations in seasonality. With increased urbanization, paving, roads and the creation of impervious surfaces, surface water runoff is increasing in volume and intensity. In a city surrounded by water, with many unused rooftops, minimal permeable green space, many impervious surfaces and a subsidy for green roofs it remains unanswered why there are not more green infrastructures, what potential they offer and the barriers to their implementation.

Masters Thesis: Green Infrastructure in Amsterdam Introduction 1-2

1.2 Research Goal and Objectives This research aims to comprehensively assess the context specific barriers to implementation of green infrastructures in the city of Amsterdam. The potential of green infrastructures in Amsterdam will be explored in relation to surface water runoff and this vast potential provides the basis and urgency for promoting green infrastructure implementation to allow for this potential to be harnessed. There are limited studies researching the challenges of implementation with regards to green infrastructures in European cities, with the only literature from a study in Hong Kong. This study aims to contribute to the gap in knowledge and the gap in the literature and provide a clear and succinct analysis of these challenges. It is hoped that the results of this research can aid the municipality in decision-making and policy writing procedures in order to improve and enhance the implementation process. This study will offer recommendations and potential solutions to the challenges, which could aid the municipality in improving the rate of implementation in Amsterdam.

1.3 Research Questions In the city of Amsterdam, why is the full potential of green infrastructure networks not being realized? i) What is the potential effect of green infrastructure in the city of Amsterdam on surface water runoff? ii) What are the barriers to implementation and expansion of green infrastructures in the city of Amsterdam? iii) Which policy instruments have the municipality implemented and how are they related to the barriers? iv) What are the solutions and potential recommendations that can be made to improve policies and implementation?

1.4 Research Strategy This study examines existing policy instruments, implementation challenges as well as the potential of green infrastructures in Amsterdam. It will also attempt to offer some recommendations and solutions to the existing barriers. This study uses the lens of implementation theory to ground this research and examine these factors in depth. Mixed methods are used to allow for comprehensive data gathering, with quantitative data collected

Masters Thesis: Green Infrastructure in Amsterdam Introduction 1-3 through the use of Q-Methodology and qualitative data from a focused literature review and expert and citizen semi-structured interviews. This approach allows for in depth expert opinions as well as quantitative data from a 21 statement Q-Sort.

1.5 Study Outline The study begins with an introduction to the context, setting and existing problem. The research questions and sub-questions are explained with a literature review of the main concepts. A conceptual model schematically illustrates the relations between concepts. Literature is used to explain the potential that green infrastructures possess in Amsterdam. The methodological chapter explains all data gathering methods, case selection as well as the data analysis and interpretation. The barriers identified from the focused literature review are explained followed by a discussion of the results gained through the semi-structured expert interviews. The study concludes with a discussion and recommendations for the municipality. I hypothesise that the greatest barrier to green roof implementation in Amsterdam is a lack of awareness of citizens, and a lack of ‘know-how’ to begin the implementation process.

Masters Thesis: Green Infrastructure in Amsterdam Introduction 2-1

2. Theoretical Chapter

2.1 Urbanization in Relation to Surface Water Runoff Urbanization is the process by which rural, natural land becomes built up or present urban areas become further intensified. This process has been on going since the emergence of agriculture nearly 5000 years ago (Gaston, 2010). Increasing urbanization and the hardening of the cities surfaces results in increased surface water runoff and water flow peaks. The creation and development of an urban area within an existing water catchment is a large change in land-use which ultimately affects the functioning of a hydrological cycle during a flooding event (Hollis, 1975). The creation of impermeable surfaces such as roads and pavements results in reduced area for interception and storage of precipitation causing increasing overland flow. In cities, the construction of an urban storm water system increases drainage density in a catchment and thus increases the speed with which with which the flow reaches a drainage line (Hollis, 1975). A well-designed storm water system is usually more efficient than natural hydrological channels and thus water speeds are usually higher and water from a much larger area is transferred more rapidly to the main river channel (Hollis, 1975). The result in cities is that there is a higher proportion of precipitation that becomes runoff, the runoff occurs quicker and the flood peak is higher than the previous natural catchment. Studies by James (1965), Martens (1968), Yücel (1974) and Brabec et al. (2002) have all found that urbanization has its greatest effect on smaller floods, but as the recurrence and size of the flood increases, the effect of urbanization becomes reduced. It has been explained that even in a rural catchment during extended rainstorms the ground becomes so saturated that it acts similar to an impervious surface and thus produces a flood type similar to its urban counterpart (Hollis, 1975). The main findings by Hollis (1975) indicate a drastic change in hydrological cycles due to urbanization with small floods increasing by 10 times due to urbanization, and floods with a return period of 100 years may double in size with 30% paving of a basin. Due to the thriving life and business in Amsterdam many people have migrated to the city, resulting in the city growing in size and an increasing number of buildings, extensive roads, paving and impermeable surfaces (Merriam- Webster, 2015). Cobble stone streets, canal houses, canals, bridges and very few permeable surfaces characterize the city of Amsterdam.

2.2 Green Infrastructure For the purpose of this study green infrastructures are defined as natural or semi-natural vegetated areas, with permeable surfaces in the city of Amsterdam including parks, green walls and green roofs that offer a wide range of ecosystem services and benefits. Green infrastructure can be broadly defined as a strategically planned network of high quality natural and semi- natural areas with environmental features, which are designed and managed to deliver a wide range of ecosystem services and protect biodiversity in both rural and urban settings (European Commission, 2013). Green infrastructure and natural permeable surfaces play an important role

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-2 in the absorption of surface water runoff during times of high rainfall. Green infrastructure is a broad term referring to the management of landscapes in a way that ecosystem services and human benefits are generated. Many municipalities have made attempts to utilize green infrastructure with aims to meet storm water management goals (Keeley et al. 2013). Green roof systems are living vegetation planted on roofs that can have positive benefits such as mitigate the urban heat island effect and enhance buildings energy efficiency and usage (IGRA; Kumar & Kaushik, 2005; Niachou et al. 2001; Zhang et al. 2012). Green infrastructure provides the opportunity for developers, contractors, public officials and policy makers to reduce the negative effects of the development on the environment (Kingsley, 2008; Zhang et al. 2012). The main goals include: long-term building performance, sustainability, reducing operational costs and energy saving (Zhang et al. 2012). World wide, governments have been introducing new policies and regulations to try and promote green infrastructure with particular focus on current building projects (Zhang et al. 2012). Germany is considered the world leader in the promotion of green roof innovations (Ngan, 2004; Zhang et al. 2012) with over 10% of households having implemented green roofs. France, Switzerland, Toronto and the United Kingdom are also making great strides in implementation and expansion of green infrastructure networks (Liu & Baskaran, 2005; Zhang et al. 2012). There are two main types of green roof technologies: intensive green roofs which have a depth of >6 inches to grow vegetation. This allows for diverse species of plants but is expensive and maintenance costs are high (Carter & Rasmussan, 2006; Zhang et al. 2012). There has been a shift from intensive green roofing to extensive green roofing which has a shallower soil depth, offers different plant choices and is lighter and thus has less structural requirements (Davis & McCuen, 2005; Zhang et al. 2012). Extensive green roofs are suited for lightweight buildings and the plants used are sedum and shrubs that self-generate, do not require a lot of maintenance and are lower in cost compared to intensive roofing (Hui, 2006; Zhang et al. 2012). The green infrastructure literature has been heavily focused on the many positive benefits it can provide (Clark et al. 2005; Zhang et al. 2012) including reducing surface temperature of the roof membrane, improving energy use of buildings (Kumar & Kaushik, 2005; Zhang et al. 2012), retaining stormwater (Carter & Keeler, 2008; Zhang et al. 2011), and improving biodiversity and habitats in urban areas (Kim, 2004; Brenneisen, 2005; Zhang et al. 2012). These benefits are most often used as the main selling point (Spatari et al. 2011). Research by Pugh et al. (2012) determined that increasing green areas in street canyons in cities could reduce street level concentrations of NO2 by as much as 40% and particulate matter by 60% respectively. Economic research by Zhang et al. (2012), studied the economic benefits of rainwater-runoff reduction by urban green spaces in Beijing, China. The vast majority of literature focuses on green infrastructure from an engineering and environmental science perspective with less research focus on policies and implementation barriers. A study by Carter and Jackson (2007) researched green roofs for stormwater management at multiple spatial scales in the United States. Investigations seldom focus on the

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-3 widespread impact of green roof application and its impact on water management in cities (Carter & Jackson, 2007). Stormwater retention data was used to model the effects of green roofing on the hydrological flows at many spatial scales. Results indicated that areas with added green roofing and less impervious surfaces would provide significantly more storm water storage. Modelling indicated that expanded green roof implementation would cause a significant reduction in peak runoff rates particularly during storm weather events (Carter & Jackson, 2007). A study by Nickel et al. (2014) identified and described the experience with ‘green’ storm water management practices in Germany with findings indicating that an integrated environmental planning approach aids the balance of environmental and urban development (Nickel et al. 2014). It was found that green infrastructure needs a long term, quantifiable goal with policies that will incentivize and support implementation. Nickel et al. (2014) specified that the transformation needs leadership from the authorities as well as active participation from all stakeholder organizations. An environmental psychology study by Baptiste (2014) assessed citizen’s opinion of a proposal for implementation of green infrastructure as a stormwater management technology in Syracuse, New York. Survey data was collected from 208 residents and a significant, positive relationship between environmental knowledge and willingness to implement green infrastructure was found (Baptiste, 2014). Despite the variety of benefits that green roofs and green infrastructure have to offer there are a variety of barriers that inhibit the application and implementation of green roofs (Carter & Fowler, 2008; Zhang et al. 2012) and green infrastructure, globally and in Amsterdam. Governments have shifted implementation policies to promote green urban space, green roofs and green infrastructure but challenges in the process still remain. It appears that there is limited application and effectiveness of green roofs in existing buildings in Amsterdam. Very few studies have focused on the major barriers hampering application and implementation except for a study by Zhang et al. (2012), which focused on a case study from Hong Kong. Green roofs have been identified as one of the best possible solutions for Hong Kong’s existing pollution problem (Zhang et al. 2012). Their study found that there was a lack of incentives from government and a failure to promote green infrastructure (Zhang et al. 2012). In Amsterdam the government provides a green roof subsidy to houses and companies for every square meter they implement. However, in many existing buildings implementation and effectiveness remains low, and this study aims to assess the barriers hindering the implementation. With rapid urbanization, and potential future climate change effects such as severe weather events, flooding and increased precipitation, there is urgency in terms of addressing and determining the factors that hinder the implementation of green roofs in Amsterdam. The municipality of Amsterdam could use results from this study in future decisions and policies. These natural areas will form the focus of the study, as it is not only the size that is most important, but also the number of these areas and the network they form in a very dense urban area. In Amsterdam land is expensive and there is a high property demand and thus any area used for green space is of significance in this study. Please see the table Appendix C-1 in the Appendix for a list of existing green infrastructures in Amsterdam.

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-4

2.3 Surface Water Runoff Surface Water Runoff also referred to as overland flow is the flow of water that occurs when excess storm-water, melt-water and other water sources flow over the earths surface (Beven, 2004). This usually occurs during periods of heavy rainfall, when soil is saturated at capacity, or when there is minimal absorption due to many impermeable surfaces (roofs, roads, pavements) that are unable to absorb the water and as a result the water runoff is sent to surrounding areas (Beven, 2004). In addition to surface water runoff causing pollution and soil erosion, it is also the primary source of urban flooding, which is a great safety hazard and can cause extensive property damage. Urbanization results in hardening of the earth’s surfaces causing increased surface water runoff in volume and intensity. In Amsterdam, surface water runoff is the flow of water that occurs when excess storm- water, melt-water and other water sources flow over many of the impermeable city surfaces and collects in canals, pools and the storm water system. During a prolonged period of intense rainfall in the city of Amsterdam increased surface water can cause small areas of flooding and an over saturation of the drainage system which results in flooding in the streets (See Appendix C-3).

2.4 Policy Instruments In this study policy instruments are any tools used by government to achieve a desired policy directive. Problems find their way into the political agenda through political advocacy. The responses to these problems are dictated by available solutions and by resources (money, knowledge, political support and organizational capacity) (McDonnel & Elmore, 1987). Public policy instruments are a set of techniques through which governmental authorities display their power to ensure and garner support to create or prevent social change (Bemelmans-Videc et al. 1998). It is essential that that these tools are carefully selected to ensure goals are achieved. Often effective programs involve a unique mix of policy instruments to achieve optimal effectiveness. Policy makers need to be familiar with the policy instruments available to ensure that the combination is carefully chosen and strategic (Bemelmans-Videc et al. 1998).

2.4.1 The Choice Versus Resource Approach In the choice versus resource approach, it is to be determined whether the instruments are classified from the perspective of the available choices government can make or whether the classification should be based on a situation the government has already decided and the categories are of the resources the government can then use (Bemelmans-Videc et al. 1998). Anderson (1977) explains four broad choices the government has with regard to approaching a public problem: (1) allow market mechanisms to act on their own, (2) use

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-5

structured options created by government, (3) use biased options, such as incentives and deterrents so that individuals can be guided voluntarily or (4) use direct control through regulation. Through the use of biased options, the government can guide citizens to act in line with public policy. It is voluntary, and the individual can defy public policy often at an added cost (Bemelmans-Videc et al. 1998). The degree of compulsion enforced by government in a situation has become one of the most important points for choices regarding public policy. (Source: Adapted from Charles W. Anderson, Statecraft, 1977, pp. 56.)

Public Policy Choices (Public Policy Strategies)

Non-intervention Intervention

Market Civil Society Household Structured Mechanisms Biased Options Regulation Options

Resource Approach

Choice Approach Figure 2-1: Schematic illustration of Public Policy Choices and the Position of Policy Instruments in Biased Options

Policy instruments carry different assumptions about the problems and about the potential solutions. The four possible assumptions are: mandates, inducements, capacity building and system-changing. Mandates require action regardless of capacity, and action would not occur with desired frequency without this rule. In Inducements the valued good would not be produced with the desired frequency in the absence of additional money, the money elicits performance. Inducements assume that the capacity exists to achieve what is required, but it can be more readily achieved with monetary incentives. In Capacity-Building, knowledge, skill

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-6 and competence are required to produce future value. In System-Changing, existing institutions and existing incentives cannot produce desired results (McDonnel & Elmore, 1987).

Table 2-1: Examples of Policy Instruments in Amsterdam and the given assumptions

Policy Instrument Assumptions Green Roof Subsidy Inducement: the capacity exists for the implementation of more (Currently Implemented) green roofs, but with the financial incentives it can be more readily achieved. Insurance Fee Reductions Inducement: the additional money and financial incentives elicit (In Development) performance. Tax Scheme Inducement: the monetary incentives allow for the goals to be (In Development) more readily achieved. Compulsory Green Roof in New Mandates: required action, and results would not be achieved at Developments the desired frequency without this. (Currently not Implemented) Partnerships with Garden Centers Capacity Building: knowledge, skill and promotion are required (In Development) to produce future value and implementation of green infrastructures.

2.5 Implementation Theory

Implementation is the actual process of putting a decision into effect or setting a plan into action. It is the act of execution. It is the realization of an application, idea or policy (Oxford, 2016). In this study the focus is on the barriers and challenges of implementation of green infrastructures, thus any act, action, policy or legislation that does not allow the plan to be put into effect acts as a barrier that challenges implementation. Jackson (2001) describes implementation theory as a study of the relationship between the structure of the institution through which individuals interact and the outcome of the interaction. Implementation theory developed out of the public policy field and provides valuable direction on the conditions for the successful and effective implementation and frameworks for conceptualising the policy implementation process (De Gruyter et al. 2015). The theoretical implementation lens will be used to assesse how policy and policy instruments create conditions for conceptualizing policy directives. The implementation process differs greatly from the decision making process where a political decision is held, compared to implementation processes where this political decision is put into action (Palffy, 2010). Implementation research shows how the policy input is transformed into concrete actions and output. Policies are actively and continuously shaped by the implementers and street level bureaucrats, with influence on design and redesign.

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-7

Many early American studies analysed single case studies regarding the ability of governments to implement their policies and programs effectively (Bardach, 1974; Sabatier, 1986). These early approaches used the top-down perspective, starting with the policy decision and examining the extent that these legal objectives were implemented and achieved over time (Sabatier, 1986). In the 1970s a different approach emerged as a response to the weaknesses of the top-down perspective. This new approach began with analysing multiple actors that interact at the local level regarding a particular issue (Sabatier, 1986). This perspective focused on the actors and their strategies used to achieve the goals. Local actors can alter the programs towards their own objectives. Bottom-upper and top-downers were motivated by different interests and concerns, and as result two very different approaches have developed. Top-downers focus on the effectiveness of governmental programs, and the way in which public officials can constrain the actions of target groups (Sabatier, 1986). Bottom-uppers are not concerned with the policy decision, but rather with the strategies of actors that are concerned with a particular policy issue and understanding the actor interaction (Sabatier, 1986).

2.5.1 Top-Down Implementation The top-down approach focuses on the effectiveness of policies and the ability for the public sector to control the behaviour of the implementers and citizens (De Gruyter et al. 2015). The focus lies at the top of the organization and the hierarchical manner in which decisions are passed down. In this perspective one begins by focusing on the law and how it is implemented. The top-down approach has been criticized for failing to take into account actors who are not decision makers, but those in favour of the top-down approach argue that the chain of command comes from the top and thus street level bureaucrats are unimportant (Sabatier, 1986). This perspective can also be difficult to use if there is no dominant policy (Sabatier, 1986). The top-down approach has four main features, beginning with the policy decision by government officials and then the approach ascertains (Sabatier, 1986): 1. The extent to which the actions of implementation officials and target groups are in line with the objectives 2. The extent to which objectives were achieved over time 3. The main factors influencing the policy output and effect 4. The formulation of the policy over time (Sabatier, 1986)

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-8

Sabatier and Mazmanian (1981) constructed a framework of the six sufficient and necessary conditions for effective policy implementation. The first three conditions are addressed in the formulation of the policy, while the last three are often the result of external political and economic pressure altering conditions during implementation (Sabatier, 1986). 1. Clear and consistent objectives 2. Adequate causal theory on how the policy will stimulate social change 3. Legal structuring of the implementation process that enhances compliance 4. Skilful implementing officials 5. Support from public and target groups 6. Socio-economic changes in conditions do not undermine political support or causal theory This frameworks strength is found in the emphasis and importance attached to the legal structure of the policy and implementation process, the six conditions are a useful checklist for analysis and understanding of implementation effectiveness and its evolution over time (Sabatier, 1986). This approach has been criticized as the focus on ‘clear and consistent objectives’ shows that many programs meet this standard and effectiveness varies. The main flaw is the perspective of decision makers that neglects other actors, ignoring strategic initiatives from the private sector, local implementers and policy subsystems (Sabatier, 1986). The top-down approach is difficult to apply to situations where there is no dominant policy but rather multiple actors present (Sabatier, 1986). This approach is criticised for underestimating how local implementers may alter policy to their own gain (Berman, 1978; Sabatier, 1986). Finally, policy formulation and implementation are distinct, however this distinction can over look that some organizations are involved in both. Although there is no legally mandating policy regarding green roofs in Amsterdam, this perspective can be applied to this research as the green roof subsidy is a form of voluntary policy supplied and implemented by the government. This study aims to examine the effectiveness of the green roof subsidy and how it is implemented. The new round of green roof subsidies has recently been implemented in Amsterdam and thus examining the evolution of the subsidy will be premature, however one can still examine the actions of the implementers, their alignment with the policy objectives and the factors influencing the policy output and effect. The six necessary conditions developed by Sabatier and Mazmanian (1980) can be applied to the green roof subsidy to examine whether the necessary conditions are present to enhance effective implementation.

2.5.2 Bottom-Up Implementation The bottom-up approach was initiated by the evident methodological weaknesses of the top- down approach (Sabatier, 1986). The approach used by Hjern et al. (1978) begins with network actor identification involved in service delivery and their goals, tasks, contacts and strategies are identified. The contacts are used to develop a network and identify the further local,

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-9 regional and national actor network involved in the various stages of governmental programs (Sabatier, 1986). The bottom-up approach focuses on the implementers and recognizes that policy is simply one of many influencers (possibly minor) on the behaviour of the implementers and citizens (Elmore, 1979; De Gruyter et al. 2015). Implementers, also known as street level bureaucrats, have various coping mechanisms and ways to simplify policy that often gains little attention (Lipsky, 1971; De Gruyter et al. 2015). In this perspective the action of the implementer is of importance. The action and service delivery shapes policy outcomes more than the actual design of the policy (Sabatier, 1986). The approach begins with focus on the actors at the local level who deliver services and by collecting information from them one can inform policy makers at the top of the hierarchical chain (Sabatier, 1986). The approaches strengths lie in the replicable methodology used for the formulation of a policy network, beginning with the perceived problem and the strategies used to address this. By not focusing on the effectiveness of objectives, the approach is able to examine interesting unintended consequences of various governmental and non-governmental programs (Sabatier, 1986). It can examine a problem area and a multitude of involved organizations with the focus on multiple actors, allowing the approach to examine interactions over time more effectively. This is not to say this approach does not have weaknesses or a danger of overemphasizing the ability of the bottom up initiatives to alter implementation and underestimate the power of the centre to create social change and achieve goals (Sabatier, 1986). The distribution of preferences are assumed to be a given and there is little examination of the efforts of other actors to alter the process and it does not examine the ability of actors to affect the subject of their interest (Sabatier, 1986). The bottom-up approach focuses on local implementation structures and the dynamics of local variation (Sabatier, 1986). It is best suited where there is no dominant policy, but rather multiple actors without power dependency, or if the researcher is interested in local conditions and their dynamics (Sabatier, 1986). The bottom-up approach can be applied to this study as it not merely the policies and policy instruments that are important, but rather their implementation and the action of the implementer (public officials and citizens) that is at the centre of this scope. Policy instruments play a role in implementation, but it is the local level actions, various non-governmental organizations and citizen awareness that have an effect on implementation. The bottom-up approach allows for the identification of a multitude of actors that play a role in green infrastructure implementation and their local dynamics and their interactions between citizens. This approach focuses on the perceived problem of a lack of green infrastructure implementation in Amsterdam then focuses on the actors and organization’s strategies and methods that are used to attempt to address this.

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 2-10

Table 2-2: Comparison between Top-down and Bottom-Up Approaches Top-Down (Sabatier & Bottom-up (Hjern et al.) Mazmanian) Initial Focus (Central) Government decision, Local implementation structure e.g., new pollution control law. (network) involved in a policy area, e.g., pollution control. Identification of major actors From top down and from From bottom (government and in the process government out to private sector private) up. (although importance attached to causal theory also call for accurate understanding of target group’s incentive structure). Evaluative criteria Focus on extent of attainment of Much less clear. Basically formal objectives (carefully anything the analyst chooses analysed). May look at other which is somehow relevant to politically significant criteria the policy issue or problem. and unintended consequences, Certainly does not require any but these are optional. careful analysis of official government decision (s). Overall Focus How does one steer system to Strategic interactions among achieve (top) policy-maker’s multiple actors in a policy intended policy results? network. Source: Sabatier (1986)

Masters Thesis: Green Infrastructure in Amsterdam Theoretical Chapter 3-11

3. Barriers of Green Infrastructure Implementation Explained

The implementation of green roofs and green infrastructure can positively contribute to enhancing buildings energy performance, reducing the urban heat island effect, improving air quality, enhanced water storage, reduced surface water runoff and improved biodiversity in cities (Zhang et al. 2012). Although the variety of benefits seem to be well-known, barriers to implementing and applying small and large scale green roofs and green infrastructure remain (Carter & Fowler, 2008). There is great opportunity for policy makers, residents, building owners and developers to try and reduce negative environmental problems (Kingsly, 2008). Globally, governments have been implementing policies and regulations to mandate green roof and green infrastructure implementation particularly for new building projects (Zhang et al. 2012). However, in the Netherlands there is still no national policy mandating green roof or green infrastructure implementation. Governments are focusing energy on solutions in the social and economic sectors to contribute to improved sustainable development (Zhang et al. 2011). Construction and real estate are considered major sectors where there is great potential for achieving improvements in development practices. In the United States, buildings contribute 38% of the total amount of carbon dioxide, and thus carbon reducing technologies are encouraged by government (Zhang et al. 2011). This has resulted in the creation of sustainable practice certifications in developments such as LEEDS and the creation of low carbon technologies to improve building performance (Zhang et al. 2011). Despite the evident barriers to green infrastructure implementation, there are very limited studies examining the barriers regarding the application of small and large-scale green infrastructures in new and existing development projects (Zhang et al. 2011) and self-funded research it is often not available to the public.

3.1 Social Barriers Within buildings containing multiple apartments and multiple ownerships, application of green roofs and management becomes complex (Zhang et al. 2012). The building could be comprised of renters and various owners. Situations regarding roof rights and roof access differ. These dynamics become complex and often the barriers cannot be overcome. There also may be various issues regarding who actually receives the various benefits of a green roof and issues of conflicts of interest may arise between various stakeholders (Zhang et al. 2011). Townshend (2007) discussed that poor utilities arrangement and enhanced complexity often acted as a barrier but not a major deterrent. In the case of Australia, Williams et al. (2010) found that the lack of an established local green industry could act as a barrier as easy to use materials were not easily accessible to the public and readily available for developers.

Masters Thesis: Green Infrastructure in Amsterdam Barriers of Green Infrastructure Implementation Explained 3-12

3.2 Institutional Barriers Institutionally, despite efforts to focus time, energy and funds into promotion of green infrastructures, barriers remain at multiple stages. A major, fundamental barrier repeatedly recurring in the available literature is that there is a lack of promotion from government and social communities in the public and private sectors (Townshend, 2007). The lack of promotion from government combined with insufficient policy implementation efforts in Hong Kong can prove detrimental to progress (Zhang et al. 2011). In new development projects, there is also a lack of efficiency in implementing green building regulations and byelaws (Zhang et al. 2011). When developers and owners proceed with green infrastructure applications they often encounter lengthily planning and approval processes, which can delay construction or force developers to rethink their strategy or in the worse case scenario, cancel the entire project (Zhang et al. 2011). Williams et al. (2010) examined the case of green roof infrastructure application in Australia and found that there was a lack of standard or industry guidelines, which can result in construction of various qualities. Many new developments aim for sustainability ratings and certifications for reasons such as public image and positive recognition. These buildings standards are highly regulated and definitive with minimal inclusion of green roofs in the green star rating schemes which could act as a deterrent to implementation (Williams et al. 2010).

3.3 Economic Barriers Depending on the type of development or owner of the existing building, economic barriers tend to be the greatest barrier to overcome. If the developer or owner does not have enough available funds for the project it becomes very difficult to proceed without the presence of a very lucrative and effective financial incentive. Getter and Rowe (2006) found that there is a lack of incentive for developers to implement a green roof as well as for owners of existing buildings. Green roofs often increase the design and constructions cost, as well as the maintenance cost (Steven & Chris, 1999; Ngan, 2004; Zhang et al. 2012), and in a project with low budgets, this makes it simply unfeasible. Zhang et al. (2011) found that often the materials needed are highly expensive. Added design features and green roof implementation involves risk due to changed practices, behaviours and possible project delivery dates which in large scale projects with many investors make the option impossible (Zhang et al. 2011).

3.4 Physical Barriers Technical difficulty during the design and construction phase can prove highly problematic to green infrastructure and green roof implementation (Steven and Chris, 1999; Getter and Rowe, 2006; Zhang et al. 2011, Zhang et al. 2012). In countries where construction companies and developers are unfamiliar with implementation there could be possible construction delays, which can prove highly costly (Zhang et al. 2011). Physical issues such as the old age of

Masters Thesis: Green Infrastructure in Amsterdam Barriers of Green Infrastructure Implementation Explained 3-13 buildings (Townshend, 2007), weak affordability to withstand wind (Steven & Chris, 1999; Getter and Rowe, 2006), poor structural capacity (Townshend, 2007) can all prevent implementation and application. Zhang et al. (2012) explains that in the high-rise buildings of Hong Kong, roofs with already small surface areas have the surface occupied by the existing building services making space for green roof implementation problematic. In the Australian case studied by Williams et al. (2010) it was found that plants used in one hemisphere are often prohibited for use in another country or hemisphere, making replicability difficult. It was found that some substrate components and mixes were not readily available in certain countries and in drier climates the inability to use potable water for irrigation made it an impractical idea to implement (Williams et al. 2010).

3.5 Educational Barriers Despite education, city living and widespread Internet access, there generally seems to be a lack of awareness of extensive green roof systems in both public and private sectors (Hui, 2006). The lack of awareness tends to be even among citizens despite their income and education level. Zhang et al. (2012) explain that there remains a lack of quantifiable data pertaining to the benefits of green roofs and green infrastructure. It is very often that these benefits are not easily quantified. There seems to be a clear lack of ‘know how’ of existing options in Hong Kong, preventing expansion when the foundation of knowledge does not exist (Zhang et al. 2011). In the case of Australia, examined by Williams et al. (2010) there is a lack of scientific data available to evaluate the applicability to local conditions. There is a lack of experience, knowledge and connection among green roof industries creating issues with material access, availability and contractors trained in their application (Williams et al. 2010). A key factor is the clear lack of demonstration projects which have the ability to inspire developers and building owners. It also creates confidence among developers with regards to the feasibility and aesthetic appeal of green roofs (Williams et al. 2010). Exemplar projects create awareness, promote the concept and often inspire others to follow the same path. Without this example it can become difficult for some to visualize.

3.6 Conceptual Model There are various barriers that prevent the implementation of large-scale green infrastructure networks in Amsterdam, as well as small-scale interventions in the historical inner city. Government, Waternet and Amsterdam Rainproof develop policy instruments (Green Roof Subsidy, Insurance Fee Reduction & Tax Scheme – that are both in development) to try and overcome these barriers. Well-developed, effective policy instruments allow for these barriers to be transcended, leading to implementation of green infrastructures. If policy instruments

Masters Thesis: Green Infrastructure in Amsterdam Barriers of Green Infrastructure Implementation Explained 3-14 prove ineffective and poorly suited, often the barriers are largely unable be overcome to achieve the desired goals.

Policy Barriers To Implementation Instruments Implementation

•Green Roof •Institutional •Green Roofs Subsidy Barriers •Green Walls •Insurance Fee •Social Barriers •Parks Reduction •Physical •Tax Scheme Barriers •Educational Barriers •Economic Barriers

Figure 3-1: Conceptual Model illustrating the relationship between policy instruments, barriers and the outcome of implementation in green infrastructures in Amsterdam

Masters Thesis: Green Infrastructure in Amsterdam Barriers of Green Infrastructure Implementation Explained 4-1

4. Research Design

4.1 Methodology For this study a mixed method design will be used including the use of focused literature reviews, semi-structured in depth interviews and a quantitative Q-sort analysis. The combination of mixed methods allows for comprehensiveness as well as triangulation that gain results, which may not have been achieved using simply one method. The focused literature review allows for the implementation barriers to be identified, the interviews consolidate or dispel the results from the literature and identifies new barriers specific to Amsterdam. The Q- Methodology is a subjective testing method which will confirm the most important and least important barriers. The research includes qualitative analysis through the use of coding of repeated statements as well as quantitative analysis with the use of the Q-Methodology.

4.2 Case Selection The case chosen for this study is the city of Amsterdam, with the area demarcated in Figure 5- 1. This case has been chosen due to the complexity of the combination of historical and aged buildings with rigid, consolidated layouts in the inner city combined with newer more open areas further from the city centre. The city is largely paved and built up with a lack of permeable ground and soil that can be infiltrated. Land prices are high and thus there are a few open green permeable areas. Due to the nature of the landscape many back gardens have subsided, have water drainage issues and are largely already saturated, making these areas unable to act as a sink for excess surface water runoff. This city has unique challenges stemming from the combination of old historical areas and new open areas further from the city centre. This study can be generalized to similar, historical European cities which have a combination of monumental buildings, newer open areas, similar climate and lack a dominant green infrastructure policy.

4.3 Focused Literature Review Two focused literature reviews were conducted, the first focuses on the existing literature regarding the potential of green infrastructures in mitigating peak flows and excess surface water runoff, with the aim to find quantification for the existing roof area available. The second focuses on the existing literature regarding barriers to implementation and expansion of green infrastructures in cities, particularly in existing buildings. In the inner city of Amsterdam, focus will be placed on implementation in existing buildings, small and large scale as well as both lighter extensive roofs and deeper intensive stratum green roofs.

Masters Thesis: Green Infrastructure in Amsterdam Research Design 4-2

4.4 Semi-structured Interviews Expert semi-structured interviews were used to gain insight and in-depth knowledge of green infrastructures in Amsterdam from the perspective of experts and stakeholders who are involved with the day-to-day planning and execution of activities. A total of sixteen interviews were conducted with eight expert interviews that were over an hour in length, with a set of guideline questions used to keep the interview focused and on track (See Appendix A). Each interview was fully recorded and transcribed verbatim for later analysis (See email). Interviewing experts provides invaluable contextual knowledge regarding the case of Amsterdam and this source of personal first hand information can often not be obtained through the relevant literature. This combination of literature, first hand personal experience and Q-Methodology allows for triangulation covering all sources of available data. Eight citizen interviews were conducted with citizens living in Amsterdam to ascertain their level of awareness regarding green infrastructure and rainproof measures.

4.4.1 Selection of Respondents In order to cover a wide range of opinions and expertise, representative respondents, and interviewees were chosen from each field or type of organization. Experts from Waternet, Amsterdam Rainproof, De Dak Dokters, Stadgenot, Deltares and an academic from Utrecht University were interviewed to gain a wide variety of expert opinions in different fields. Citizens living in the city of Amsterdam were also interviewed to ensure that public perception and opinion was taken into account. The citizens were of upper income and higher educational levels.

4.4.2 Transcribing, Coding and Analysing The 8 expert semi-structured interviews and 8 citizen interviews were transcribed verbatim in order to help with coding of repeated statements and opinions needed for analysis (See email). Repeated statements and highlighted barriers were given a code and placed into a table of collected data with each corresponding reference for analysis (See Table 6-2). Other important findings were highlighted so that the quotes could be used in later discussion.

4.5 Q- Methodology This study makes use of Q-methodology, which was developed by William Stephenson in the 1930s (McKeown & Thomas, 1988; Coogan & Herrington, 2011). It was developed to allow respondents to represent their subjective opinion for further inspection and comparison. This methodology does not test the participants but rather asks the participants to illustrate a vantage point that is meaningful from their perspective (Coogan & Herrington, 2011). Sets of evaluations are produced which are then analysed which reveals the experts who have ranked

Masters Thesis: Green Infrastructure in Amsterdam Research Design 4-3 the perspectives in the same sequence. These overall correlations are then correlated to form connections between experts, their opinions and their expertise. Q-methodology is ideal for this study as it can be conducted directly after the expert interview and it involves ranking experts opinions of which they believe is the greatest barrier to implementation of green infrastructures in Amsterdam. This helps consolidate the findings from the literature and also gives an indicator of the experts in each field and their varying perspectives (Coogan & Herrington, 2011).

4.5.1 Design Concourse The Q-methodology is designed with a bell-curved distribution grid known as the Q-grid and a set of statements are produced with each one representing a different factor making sure to include all sub-issues within the topic (Coogan & Herrington, 2011). Only by ensuring all areas of the topic are included can one be sure that they are covering all subjective viewpoints possible (Coogan & Herrington, 2011). A set of 21 statements (See Appendix B-1) was produced, each containing a different statement of a perspective, which the respondent can either agree or disagree with. Statements are carefully chosen to be representative of the literature and not to include repetition. It is only once the respondent sorts the statements that they gain meaning (Watts & Stenner, 2005).

4.5.2 Selecting Respondents The respondents for the Q-Method will be the same as the respondents that were interviewed. After each semi-structured interview, the Q-method will be conducted in order to gain quantitative data regarding their opinion. It is a tactile and engaging method, which provides a good conclusion to the interview. In order to cover a wide range of opinions and expertise, representative respondents, were chosen from each field or type of organization. Experts from Waternet, Amsterdam Rainproof, De Dak Dokters, Deltares and an academic from Utrecht University were interviewed to gain a wide variety of expert opinions in different fields.

4.5.3 Q-Sorting In sorting the statements, the respondent’s subjectivity is shown (Coogan & Herrington, 2011). The terms of reference for sorting are given: strongly disagree, neutral and strongly agree. The 21 statements are given to the respondent who is advised to first sort them into three piles as per the terms of reference. The Q-Grid (See Appendix B-2) is arranged with fewer rows in the furthermost tails (-5 and +5) and the neutral column (0) having the majority of rows. They are first asked to select the statements to fill the furthermost column and then methodically fill the grid from left (strongly disagree) to right (strongly agree). Once each statement has been placed on the Q-grid, the results are then recorded in a data entry sheet.

Masters Thesis: Green Infrastructure in Amsterdam Research Design 4-4

4.5.4 Data Analysis and Interpretation The Q-Methodology data will be analysed by hand to correlate experts of the same opinion and their field. The analysis will indicate the barriers experts believe proves the most inhibiting in green infrastructure implementation, the least important barriers as well as show relationships between similar expert opinions and their fields.

4.6 Operationalization The study has been operationalized through the use of Q-Sort statements, which are opinionated statements linked to the barriers of green infrastructure implementation. The statements can be found in Appendix B. The barriers are operationalized through the use of a coding system in which I create codes for the identified and discussed barriers that are repeatedly mentioned in the interviews, with the results illustrated in Table 6-1.

4.7 Strengths of Mixed Methods Qualitative research is widely regarded for its trustworthiness and credibility (Bryman, 2009). The use of more than one method enhances the credibility as the use of the focused literature review, interviews and Q-Methodology allow for triangulation and greater comprehensiveness (Bryman, 2009). Transferability is important to the validity of this study and due to the interviews grounded on the same questions and the Q-Methodology grounded on the same statements, this study is highly replicable. All data and transcripts from the study have been kept for future purposes. In order for valid focused literature review results, a wide variety of documents were analysed. This increases the range of perspectives taken into account and provides a fair representation of existing research and viewpoints. The use of mixed methods allows for the strengths of each method to be used to provide a broader perspective on an overall issue. Researcher bias can result in a particular, favoured method being employed, but in mixed methods the use of multiple methods does not allow for this. More data from mixed methods allows for more comprehensiveness as apposed to an often one-sided approach of a single method. This study aims to gain subjective expert perspectives on the most important implementation barriers in Amsterdam. Through the use of semi-structured interviews this can be achieved in a personal, relaxed and open interview. The Q-Methodology involves ranking of these subjective perspectives allowing for comprehensiveness in data collection, as the Q-Sort can further confirm semi-structured interview results.

Masters Thesis: Green Infrastructure in Amsterdam Research Design 4-5

4.8 Limitations of Methods There are two arguments against the use of mixed methods, the first argues that research methods carry epistemological commitments and the second argues that quantitative and qualitative research are separate paradigms (Bryman, 2009). The embedded methods arguments explains that the decision to employ a particular form of data collection is not simply how one goes about this task, but rather a commitment to an epistemological position that is consistent with interpretivism (Bryman, 2009). The paradigm argument views quantitative and qualitative research as paradigms in which assumptions, values and methods are intertwined in a complex manner that makes them incompatible between paradigms (Bryman, 2009). The use of mixed methods has its limitations, combining multiple methods, qualitative and quantitative is time consuming and often expensive. In mixed methods, qualitative methods are often first used as an exploratory tool before the use of a survey or other method of quantitative data collection. This results in the qualitative method only being used in an exploratory manner while the quantitative method is used as an exploratory tool as well as to define the problem and potential solutions (Bryman, 2009). Quantitative research should be reliable and valid, however Q-methodology has been criticized for often providing unreliable results. Q-Methodology results are said to improve in reliability with increased replication (Bryman, 2009). This study aimed to gather a large quantity of Q-methodology data to gain reliable results. The Q-methodology has been criticized for resulting in generalizations, but the main aim of using this methodology is not to categorize and generalize viewpoints, but rather to reveal the importance of a range of subjective perspectives.

Masters Thesis: Green Infrastructure in Amsterdam Research Design 5-1

5. The Potential of Green Infrastructure in Amsterdam

For the purpose of this study, the study area of Amsterdam will be bound by the A10 high way. This area is used as it included both the historical inner canal belt as well as newer areas with more space further from the city centre. This allows for both types of areas to be represented in this study. See Figure 5-1 below for the case study area.

Figure 5-1: Map of the study area of in Amsterdam, The Netherlands. (Source: www.draftlogic.com)

5.1 Current Organizations and Companies There are multiple organizations in Amsterdam, which focus on among other things, green infrastructure, rainproof solution implementation and creating awareness. National

Masters Thesis: Green Infrastructure in Amsterdam The Potential of Green Infrastructure in Amsterdam 5-2 governmental and regional governmental priorities and focus differ, and thus the majority of efforts come from local and regional public companies with their sole focus on Amsterdam.

5.1.1 Waternet Waternet prides itself as the only company in the Netherlands that focuses on the holistic water cycle. Waternet is responsible for purifying water, producing drinking water, maintaining clean water channels as well as flood protection in Amsterdam and the Netherlands. The company works on behalf of Water Board Amstel, Gooi and Vecht as well as the City of Amsterdam (Waternet, 2016). The company has five core values the first, sustainability, in ensuring that all processes align with each other to ensure that they contribute to the environment, society and the economy. Safety is paramount in maintaining clean drinking water while also trying to produce innovative creative solutions. Waternet has a great respect for nature, and also tries to look beyond their own work and be open to new ideas. They are open to innovative solutions in energy, waste and spatial planning. The company is centred under one roof, making it approachable and easy for customers to contact (Waternet, 2016). Waternet is involved in many polder and dike dredging projects in the Netherlands and works towards the ideal of ‘keeping ones feet dry’ which citizens pay a taxes for.

5.1.2 Amsterdam Rainproof Amsterdam Rainproof is an organization created by Waternet with the goal to get the inhabitants of Amsterdam to work together to create a city which can withstand the increasingly frequent cloud bursts. The downpours in the city cause damage, especially in hardened and paved areas of the city where there is nowhere for the water to infiltrate (Amsterdam Rainproof, 2016). Amsterdam Rainproof aims for this excess water to be used in a more intelligent manner by promoting rainproof solutions, through engaging citizens, entrepreneurs and inhabitants to not just create projects but to try make them rainproof too (Amsterdam Rainproof, 2016). Through the use of permeable paving, green roofs and front gardens the excess water can be utilized in a positive way to create a smart and aesthetically pleasing city. Amsterdam Rainproof does not start their own large-scale projects but rather aims to be a facilitator and offer guidance to initiatives started by active citizens. Amsterdam Rainproof tries to create awareness and engage the public (Boxem, 2016). They have created various info graphics and brochures that are distributed at event days and fairs (Boxem, 2016). The set of brochures are aimed at ordinary citizens to show them concrete ways in which they can makes their building, their square, their neighbourhood, street and their garden more rainproof (See Appendix D-1). This is just one of the methods they use to engage the public and attempt to make rainproof solutions considered and accessible.

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5.1.3 De Dak Dokters The Dak Dokters are a full-service organization that is responsible for the design, implementation and maintenance of green roof projects. The organization has architects, carpenters, roofers and landscaping architects working together under one roof (De Dak Dokters, 2016). The goal of the organization is to create a positive impact and design a healthier city by realizing these projects. The company has been responsible for realizing more than 1000 green roof projects since 2010 and sees the often unused roof space as a possible engine for a sustainable city of the future, with these spaces transformed for nature, recreation, water storage, food and energy (De Dak Dokters, 2016). They manage private and commercial properties for many clients and help to obtain the grant for the green roof subsidy.

5.1.4 De Groene Grachten De Groene Grachten is an initiative started by Wubbo Ockels that is committed to creating sustainable, historic buildings in the Netherlands. De Groene Grachten is a leader in the Netherlands which aims to successfully preserve old, historic buildings while converting homes, offices, hotels, museums and churches into more energy efficient buildings and into buildings of the future (De Groene Grachten, 2016). The initiative does this through providing advice, guidance on implementation, experience in delivering innovative projects and through promotion and events. Interested citizens can gain personalized advice for what is possible in their situation and they can also get access to comprehensive implementation plans (De Groene Grachten, 2016).

5.1.5 De Gezonde Stad De Gezonde Stad consists of a committee of actors that are responsible for coordinating projects and achieving sustainability goals in Amsterdam. De Gezonde Stad aims to create a healthy city with the vision of combined strength through the commitment of residents, businesses and governments with the common goal of producing a healthy city (De Gezonde Stad, 2016). A healthy city is one that is designed for the future, is viable and smart through practical and applicable solutions. De Gezonde Stad has three main goals of more green areas in the city, cleaner air and a healthy climate through the reduction of CO2 emissions (De Gezonde Stad, 2016). This can be achieved through boosting sustainable initiatives and connections between residents and businesses in the city. Amsterdam aims to reduce CO2 emissions by 40% in 2025 compared to records from the 1990s. The idea of a healthy city sets targets for a carbon neutral city by 2040 (De Gezonde Stad, 2016). De Gezonde Stad encourages the use of cycling and electric vehicles to produce cleaner air. De Gezonde Stad is committed to creating, developing and preserving more green areas and parks in Amsterdam (De Gezonde Stad, 2016). Partners of De Gezonde Stad include the City of Amsterdam, the

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National Postcode Lottery, Intratuin and Mac Bike. It is through the connections with these stakeholders that sustainable solutions and initiatives can be put into practice.

5.1.6 Rooftop Revolution Rooftop Revolution is a project with joint participation from De Groene Grachten and De Gezonde Stad, which aims to have more than 10% of metropolitan roofs vegetated by 2020 in the Netherlands (De Gezonde Stad, 2016). In Amsterdam, less than 1% of flat roofs are green but with many flat roofs available, the opportunities are endless. Rooftop Revolutions aims to take the financial barrier out of implementing green roofs by offering a crowd-funding platform for the neighbourhood where they create the green roofs. Residents will have access to a co- financing scheme, practical guidance and essential tools to help streamline the process (De Gezonde Stad, 2016). This approach is expected to make urban nature reserves in the Netherlands a possibility, and create green lungs in the inner city. These green roofs can contribute to improved air quality, CO2 reduction, biodiversity, energy efficiency and noise reduction (De Gezonde Stad, 2016). In Amsterdam alone there is a flat roof surface area of 2000 football fields still available. The pilot project ‘Hectare Daknatuur’ was sponsored by Rabobank Amsterdam and is a project which follows the ‘learning by doing’ approach, but also serves as an example for citizens of what is possible and creates awareness in the city (De Gezonde Stad, 2016).

5.2 Current Policies & Incentives

5.2.1 Green Roof Subsidy The municipality of Amsterdam has recently implemented a green roof subsidy from 2016 until 2018 for owners and tenants of existing buildings over the age of 5 years in Amsterdam. There are various conditions that need to be met in order to qualify for the subsidy including (Gemeente Amsterdam, 2016):  A green roof or green wall area of 30 square meters or more  The water storage capacity must be a minimum of 20 litres per square meter  A green wall must be clearly visible in the public space  The green roof can only be constructed after the subsidy is granted  The required permits are in place  No previous funding for the green roof was obtained  Your green roof must be constructed within a year of receiving the subsidy  The green roof or wall must be maintained for a minimum of 5 years  All required documents must be received by the municipality to determine eligibility

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 You make the roof accessible to necessary officials  The structural reliability remains your responsibility  The owner or tenant needs to assess whether the building has the structural capacity for a green roof  Tenants need written consent from the building owner

The subsidy does not cover more than 50% of the construction costs and covers a maximum of 30 euro per square meter of green roof or green wall to a maximum total of 100 000 euro (Gemeente Amsterdam, 2016). If the green roof or wall has a greater water storage capacity than 30 litres per square meter, then it is eligible for a grant of 50 euro per square meter (Gemeente Amsterdam, 2016).

5.2.2 Tax Scheme Amsterdam Rainproof is currently researching the potential for a tax scheme where homes and apartments implementing rainproof solutions that reduce their stormwater runoff receive a tax reduction on the bill they pay to Waternet for stormwater management (Boxem, 2016). This scheme is currently in the early stages of development and there are still many issues regarding the viability. Critics argue that Waternet gains the benefit of reduced stormwater levels while contributing nothing towards this initiative (Boxem, 2016). It still remains to be seen whether this will be approved and a concrete scheme developed.

5.2.3 Insurance Fee Reduction Amsterdam Rainproof is currently focusing their efforts on developing an insurance reduction scheme for homes and apartments that implement certain rainproof measures. The scheme is still currently in the early stages of development and Amsterdam Rainproof is trying to organize this incentive program with insurance companies (Boxem, 2016). Challenges remain, as insurance companies are reluctant to lose profit over measures they believe Waternet and Amsterdam Rainproof should concern themselves with. It is still uncertain whether the scheme will be realized (Boxem, 2016).

5.2.4 Lack of Policy Currently in Amsterdam there are no mandatory policy regulations requiring current building owners or developers to meet a green standard or install a green roof. Any green roofs and green walls installed are voluntary and there are not requirements set by government or the municipality. Other European cities have taken the lead and put green roof requirements into legislation and policy, with Germany leading the forefront with the most green roofs (Mentens et al. 2006). Munich has employed a wide variety of measures to promote green roofs in the

Masters Thesis: Green Infrastructure in Amsterdam The Potential of Green Infrastructure in Amsterdam 5-6 city including well established instruments such as regulations in urban land use plans, subsidies for citizens installing green roofs voluntarily, and reductions or discounts on their storm water fees or taxes (Ansel & Appl, 2011). The policy requirements of all suitable flat roofs greater than 100 meters square being converted to green roofs has resulted in this becoming an national and regular construction standard (Ansel & Appl, 2011). Copenhagen, Denmark has developed a green roof strategy and policy over the past two years where all roofs with a pitch angle of less than 30° must be converted to a green roof unless there are structural challenges preventing this (Ansel & Appl, 2011). This programme was the result of a long-term comprehensive public information campaign lead by public officials and ultimately joined by the politicians (Ansel & Appl, 2011).

5.3 Quantifying the Current Situation The City of Amsterdam has created an interactive green roof map for Amsterdam which shows the location of all green roofs in the city, as well as their size, an image and the type of green roof it is (sedum, solar, grass, roof garden, green wall or herb roof garden). Using the green roof map available at: http://maps.amsterdam.nl/groene_daken/ I was able to quantify the current area of green roof implementation. I calculated the combined area of each different type of green roof as per the data available on the City of Amsterdam website. I used this to calculate the total area of sedum roofs, roof gardens, grass roofs, solar-sedum roofs, green walls and herb green roofs. I then used a public access map tool called Draft Logic (available at draftlogic.com) to plot points by hand onto the map of Amsterdam and calculate the area of each park, cemetery, botanical garden and sports parks. I then tabulated and calculated the results in Microsoft Excel 2011. From my calculations with the draft logic tool, I was able to quantify the approximate total permeable green area in Amsterdam. The ground level green infrastructure consisted of parks in Amsterdam with an area of 2,96km2, the Zoo, Botanical Gardens and Plantations 3,41 km2, Cemeteries 0,25 km2 and the Sport Parks measuring 0,12km2. The combined ground level green infrastructures measured 3,9km2. Green walls, herb green roofs, grass green roofs, sedum green roofs, roof gardens and solar-sedum roof gardens had a combined total area of 0.047km2. The total permeable green area in Amsterdam measures approximately 6,98 km2 of a total study area of 46,87 km2. From my calculations I can deduce that approximately 14,9% of the area used in this study in city of Amsterdam is permeable.

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Table 5-1: Approximate calculations of the current permeable green areas present in Amsterdam (km2)

Type of Green Area Total Area Parks 2,96km2

Botanical Gardens & Plantations 3,41km2 Zoos 0,15km2 Sport Parks 0,12km2 Cemeteries 0,25km2

Sedumdaken 0,03 km2

Green Walls 0,002 km2 Kruidendaken 0,001 km2 Grasdaken 0,0002 km2 Daktuinen 0,013 km2

Solar-Sedumdaken 0,001 km2

Combined Total Green Area 6,98 km2 Amsterdam Study Area 46,87 km2 Green Area as a Percentage of Study Area 14,9%

5.4 Quantifying Potential Area Available Amsterdam Rooftop Solutions and Rooftop Revolution have found that Amsterdam has 12km2 of rooftop space available for green roof initiatives. This is more than 25 times the size of Vondelpark that could be productive, green urban space. Currently, less than 1% of these rooftops are green (Rooftop Revolution, 2016). The World Health Organization (WHO) recommends that cities should have at least 9 square metres of open green space for each inhabitant. This is a minimum figure and cities that provide more space are usually cities that have a greater liveability index and provide a higher quality of life (Baharash Architecture, 2013). Amsterdam has 17.62 square meters of pubic recreation green space per person while Vienna often voted the most liveable city has approximately 120 meters square of green space available per person (Green Surge, 2015).

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5.5 Benefits One often-encountered issue in persuading the public and developers to implement green roofs is the lack of quantifiable scientific data on the benefits it provides. Many positive effects and benefits are soft features that are hard to measure, difficult to monetize and thus literature on this still remains minimal. The more literature made available on the positive benefits of green roofs in cities, the more persuasive the argument to the general public and developers.

5.5.1 Water Increasing urbanization in cities has resulted in an increase in impermeable surfaces with many negative consequences for the city environment, services and infrastructures (Berndtsson, 2010). Infiltration is reduced and as a result greater stress is placed on existing storm water infrastructure and flooding of sewers can increase. The additional component of global warming and changing weather patterns can increase precipitation in some areas (Arnell, 1999; Bates et al. 2008). New developments in cities are often made without consideration of green urban areas, exacerbating the problem further. Since sustainable development has gained more ground people have started reconsidering conventional storm water designs and focusing on storm water as a beneficial resource rather than waste (Berndtsson, 2010). Where there is a clear lack of space in cities, available roof space can offer a more sustainable method of attenuating stormwater runoff, reducing urban flood risks and improving the urban water cycle to one closer to the original natural cycle (Bengtsson et al. 2005; Mentens et al. 2006; VanWoert et al. 2005; Berndtsson, 2010). Berndtsson (2010) argues that green roofs need further development for implementation in urban settings with great potential for improvements. Green roofs retain water and thus have the ability to delay and lower peak runoff compared to a hard impermeable roof surface (Berndtsson, 2010). Retained water can be used by plants for transpiration or will evaporate, this process results in the runoff reduction and delay in peak discharge (Berndtsson, 2010). Green roof water retention is influenced by roof characteristics (slope, vegetation type, soil) and the prevailing weather conditions (Berndtsson, 2010). The soil characteristics as a result of weather patterns have great influence on the water retention and runoff. Many studies have shown that green roofs have an effect on reducing stormwater runoff and retention, usually depending upon substrate thickness, type of precipitation event, vegetation cover and in some cases the slope of the roof (Berndtsson, 2010). Mentens et al. (2006) found that intensive green roofs reduced annual runoff by 65-85% of the total annual precipitation. Carter and Rasmussen (2006) found that the smaller the amount of precipitation, the greater the amount of rainfall that was retained, with Simmons et al. (2008) finding that the general delay by green roofs was 10 minutes peak to peak. DeNardo et al. (2005) conducted research that that found that the green roofs delayed the peak runoff response on average by 2.0h, while Moran et al. (2005) found a 30-minute reduction for 60%

Masters Thesis: Green Infrastructure in Amsterdam The Potential of Green Infrastructure in Amsterdam 5-9 of rainfall events recorded. It is important to note that runoff does not occur until the soil has reached field capacity (saturation) (Bengstsson et al. 2005). A number of researchers agree upon the type of substrate having a greater influence on the water retention than the vegetation type (Dunnett et al. 2008; Monterusso et al. 2004; VanWoert et al. 2005). Vegetation influences water retention in periods of lower water availability and less so in the wetter cooler seasons (Dunnett et al. 2008). VanWoert et al. (2005) found that the substrate played the greatest role in water retention with vegetated roofs retaining 60.6% of rainfall, substrate roofs 50.4% and the gravel roofs retaining 27.2% of precipitation. In warmer seasons with higher evapotranspiration, the retention capacity regenerates faster and thus the roof can hold more precipitation (Mentens et al. 2006). Studies have found contradictory evidence with regard to the influence of slope on water retention and thus this factor needs further investigation (Berndtsson, 2010). Carter and Jackson (2007) researched the influence of green roofs on the urban water catchment, with their hydrological modelling indicating that the influence of the green roofs on the catchment is dependent upon the size of the rainfall event. Even widely implemented green roofs would have minimal effect upon a heavy rainfall event that lasts longer than 24 hours (Carter & Jackson, 2007). Researchers have indicated that green roofs cannot be viewed as the only mitigation measure, but efforts should rather be focused on watershed scale stormwater management (Berndtsson, 2010). Results do indicate that green roofs show potential in managing stormwater from small rainfall events in highly urbanized and developed areas (Berndtsson, 2010). Limited research has focused on the quality of the runoff with some studies indicating contradictory results. The quality of the stormwater runoff is tested by measuring the quality of the source water compared to the ultimate runoff after it has moved over and through the various surfaces (Berndtsson, 2010). Rainwater is most often considered non-contaminated but may be acidic and contain some nitrates. The most common contaminants include heavy metals, pesticides, nutrients, pathogens and some petroleum hydrocarbons (Berndtsson, 2010). Berndtsson (2010) found that within the relevant literature, researchers are of a common opinion that there is great potential and numerous benefits from vegetated roofs in the urban setting. With that being said, there are limited studies and results that accurately quantify these benefits. Some of these studies contain contradictory results, possibly due to short study times and thus need further investigation (Berndtsson, 2010). Implementation and vegetated roof decision makings needs to use a multi-disciplinary approach, with further research on optimizing the potential benefits. A holistic and multi-disciplinary approach will ensure that factor optimization will not negatively affect other factors. Berndtsson (2010) calls for further research in the urban context as well as longer-term studies which could provide more reliable results. Studies by Bengtsson (2005) found that 64% of annual runoff can be reduced by evapotranspiration in sedum green roofs in Malmö, Sweden. This was also confirmed by

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Kohler et al. (2005) who found that sedum roofs with a 5-12cm thick substrate can reduce annual precipitation through evapotranspiration by 60-79%. Studies from Chicago, Philadelphia and Portland (Scholtz-Barth, 2001) found that extensive green roofs could retain an average of 65% of precipitation. The substrate depth and characteristic have a large influence on water retention, while vegetation has a lesser effect on retention compared to that of the substrate. The vegetation plays a greater role in transpiration, providing shade and impacting the urban heat island effect (Fioretti et al. 2010). The effect that the roof slope has on retention still remains unclear and studies offer contradictory results (Fioretti et al. 2010). The volume of water retained determines the effect on the runoff peaks and the amount of delay before the stormwater reaches the drainage network. Water continues to flow even after the storm event, but the delay is caused by water entering the green roof that filters through the soil, drains and filters through multiple layers before it can exit as runoff (Fioretti et al. 2010). This delay is important for urban catchment studies and the comparison to the usual peak flow data (Palla et al. 2008). The soil moisture content before a rainfall event influences the amount of precipitation that will be retained. Soil has a finite saturation level and a drier matrix will be able to hold more precipitation, thus if the soil is saturated before a rainfall event, only a small portion of precipitation will be retained (Moran et al. 2005 ; Connely & Liu, 2005). Research should focus on the roof scale in order to evaluate the potential and practicality of implementing green roofs in a sustainable storm water system (Fioretti et al. 2010). Urban watershed responses can be modelled in order to determine how green roofs can be used in the developed urban water catchment (Fioretti et al. 2010). The study by Villarreal et al. (2004) illustrated the potential of green roofs as stormwater storage in the inner city in Sweden with Carter and Jackson (2007) also indicating that total peak outflow volumes in the urbanized watershed in the Piedmont region in Georgia was greatly reduced by additional storage from green roofs. Results indicate that green roofs can significantly reduce the stormwater runoff through volume reduction and peak attenuation, although in periods of intense, prolonged rainfall this performance is reduced (Fioretti et al. 2010). Further studies need to further investigate this performance in a wider variety of climates, with long term monitoring to further enhance progress in the urban planning development field (Fioretti et al. 2010).

5.5.2 Habitat and Biodiversity Green roofs with a vegetated surface and substrate provide a variety of ecosystem surfaces including and increased urban wildlife habitat (Oberndorfer et al. 2007). Work by Oberndorfer et al. (2007) examined the combination of biotic and abiotic components that contribute to the overall ecosystem effects. Policy makers and the public are becoming increasingly aware of the benefits of green roofs in urban environments. Green roofs are often treated as an engineering and horticultural challenge, rather than a functioning ecosystem that can deliver many services (Oberndorfer et al. 2007). Extensive green roofs are an adaption of the original roof garden

Masters Thesis: Green Infrastructure in Amsterdam The Potential of Green Infrastructure in Amsterdam 5-11 concept, they usually have a shallower growing medium, are less costly and require less maintenance and thus more functional than roof gardens (Dunnet & Kingsbury, 2004). Rooftop conditions are difficult for plant survival as the conditions are usually dominated by drought, intense heat, moisture stress, harsh sunlight, and high wind (Dunnet & Kingsbury, 2004). Plants suited to this environment need to be able to endure extreme conditions and have drought and stress resistance characteristics (Grime, 2001). These plants include evergreens, succulents or CAM (crassulacean acid metabolism) plants (Lee & Kim, 1994). Sedum species have proven the most suited and have outperformed the other groups in shallow substrates where conditions are particularly difficult. Shallow substrates have a much higher desiccation rate, with large fluctuations in temperature (Oberndorfer et al. 2007). Substrates are usually largely mineral based with some organic matter. The harsh climatic conditions restrict the usage of certain plant species. Native plants are often considered ideal as they are already adapted to climatic conditions and they are indigenous (Oberndorfer et al. 2007). However, many native species cannot withstand the harsh conditions of the shallow substrate making them unsuitable. Wind stress is another important factor which also affects plant selection and suitability (Oberndorfer et al. 2007). The green roof habitat has shown potential for contributing to local habitat biodiversity and conservation. The green roof is often home to many insects such as beetles, ants, bugs, flies, bees, spiders and grasshoppers (Coffman & Davis, 2005; Oberndorfer et al. 2007). There have been cases recorded of rare species of beetles and spiders found on green roofs (Brenneisen, 2006; Oberndorfer et al. 2007). Some roof areas are often used by nesting birds and thus important in their breeding cycle (Baumann, 2006; Oberndorfer et al. 2007). The species richness and density of the insect communities was positively correlated to the plant species richness (Gedge & Kadas, 2004; Oberndorfer et al. 2007). These findings helped to initiate action from different local and national conservation groups to promote green roof habitats in the United Kingdom and Switzerland. These findings have also sparked discussion on new strategies to try and maximise the green roof habitats in order to further increase the biodiversity (Brenneisen, 2006; Oberndorfer et al. 2007). In order to improve these habitats, higher plant species diversity encourages complete resource use because ecosystems of low species diversity are more vulnerable to climatic fluctuations (Oberndorfer et al. 2007). Research has indicated that using local plant species is less important for biodiversity than ensuring that the functional, structural and phonological properties are present to encourage synergy in the ecosystem (Smith et al. 2006; Oberndorfer et al. 2007). A variety of functional types is critical to ensure high biodiversity (Oberndorfer et al. 2007). The size of the green roof and the type of urban environment impacts on the habitat and biodiversity. Oberndorfer et al. (2007) argue that in order to improve green roof functioning and potential, it is important to improve the understanding of the complex interactions between vegetation, growing media, organisms and the ecosystem functioning as a whole. Research needs to focus on the connection between biotic communities and the ecosystem functioning in

Masters Thesis: Green Infrastructure in Amsterdam The Potential of Green Infrastructure in Amsterdam 5-12 order to improve the efficiency and performance of the green roof. Extensive green roofs represent a shallow substrate habitat and their resulting biodiversity, but it is important to note that some of the harshest and most unproductive habitats can have an incredibly high species richness (Larson et al. 2000; Oberndorfer et al. 2007).

5.5.3 Air Quality In cities with high pollution levels, conventional pollution management programs focus on controlling the source of the pollution, which manages to control the new pollutants rather than focusing on pollutants that are currently in the air (Yang et al. 2008). A new method of addressing this is through using urban vegetation which makes use of the dry deposition process to reduce pollutants in the city air and improve microclimate effects. Vegetation has a high surface area, with many branches and foliage which can make it a efficient sink for pollutants (Yang et al. 2008). It has also been seen that urban vegetation can lower ambient air temperatures by altering albedos of some urban surfaces through evapotranspiration which leads to cooling (Yang et al. 2008). A lowered temperature slows down many photochemical reactions, resulting in less other pollutants such as ozone (Rosenfeld et al. 1998; Akbari, 2002). A number of studies have shown that trees can make a significant contribution to air quality and pollution reduction in cities. A study by Nowak et al. (2006) calculated that urban trees in the U.S remove 711 000 metric tons of air pollution annually. These findings resulted in the United States Environmental Protection Agency (EPA) ensuring that tree planting became state implemented in 2004 (Yang et al. 2008). In cities this is challenging as there is not always space to plant trees in a densely constructed and built area. Green roofs are offered as a unique solution to this challenge as the often make up 40-50% of the impermeable area of a city (Dunnet & Kingsbury, 2004; Yang et al. 2008). There are a limited number of studies effectively quantifying the capacity of green roofs to remove air pollution, and thus there is a lack of information for governments, developers and citizens to effectively judge the potential and benefits (Yang et al. 2008). A study by Currie and Bass (2005) calculated that 109ha of green roofs in Toronto could act as a sink for approximately 7.87 metric tons of pollutants annually. Deutsch et al. (2005) used the UFORE model to simulate results if all the roofs in Washington DC were green roofs. They found that this could act as a sink for 58 metric tons of air pollutants in the hypothetical scenario. A study by Corrie et al. (2005) focused on NO2 reduction as a result of green roofs in Chicago. Their results indicated that 20% green roof cover in Chicago could results in a sink of 806.48- 2769.89 metric tons of NO2 depending on the vegetation type planted. Tan and Sia (2005) investigated the levels of acidic gaseous pollutants and particulates above a 4000m2 roof before and after the installation of a green roof. They found that acidic gaseous pollutants were reduced by 6%, and particulates by 37% after the installation of the 4000m2 green roof. Yang et al. (2008) researched the Chicago area, which is the leader in North America in terms of total area of green roofs installed. In Chicago there are extensive, intensive and semi-

Masters Thesis: Green Infrastructure in Amsterdam The Potential of Green Infrastructure in Amsterdam 5-13 intensive green roofs. Yang et al. (2008) used the big-lead resistance model to measure the dry deposition of air pollutants in the plants. Results indicated that air pollutant concentrations, weather, growth of the plants and vegetation cover all had an effect. The dry deposition speeds have the greatest influence on the amount of air pollution removal (Yang et al. 2008). The study indicated that 85kg ha-1yr-1 per green roof was removed annually, and that 97 ha-1yr-1 was removed per canopy cover annually. Although the results indicated a large amount of air pollutants can be removed by green roofs, it cannot as of yet be used as the singular measure due to the high cost of implementation (Yang et al. 2008). Currently it can be used as an effective pollution mitigation tool. A study by Pugh et al. (2012) discussed how street level pollution and high concentrations of NO2 and particulate matter (PM) have been linked to increased mortality and disease. NO2 and PM have varying deposition rates depending on the nature of the surface, while deposition rates to vegetation are much higher than that of a built surface (Pugh et al. 2012). There are a limited number of studies that fully take into account the complex interactions between vegetation, the urban form and the lengthily residence time of air in an urban canyon (Pugh et al. 2012). Results indicated that increased vegetation in street canyons can reduce NO2 and PM by 40% and 60% respectively. Thus, increased vegetation can result in a substantial air quality improvement, at the street-level in dense urban areas (Pugh et al. 2012). Although these studies prove through field measurements that green roofs are effective in air pollutant reduction, the results are difficult to project and model at a larger scale (Yang et al. 2008). Every context is different with a variety of external factors (climate, wind patterns, pollution levels, plant life cycles) that make each setting and each roof unique. Thus the results are difficult to extrapolate for large city areas. Although theses studies indicate the potential green roofs have in terms of pollution control and mitigation, there are still many aspects of mitigations that remain unclear (Yang et al. 2008). More studies are still needed to provide more concrete quantitative information to argue the case for green roofs as an air pollution reduction measure.

5.5.4 Urban Heat Island Effect Urbanization and the increase in urban inhabitants has caused urban sprawl especially in developing countries (United Nations, 2004). This is often linked to increasing urban temperatures as a result of the urban heat island effect (UHI). The UHI is a change in energy balance in urban areas as a result of urban canyons (Landsberg, 1981; Susca et al. 2011), varying thermal properties of urban materials (Montavez et al. 2000;Susca et al. 2011), and an increase in hardened urban surfaces that reduce evapotranspiration (Takebayashi & Moriyama, 2007; Susca et al. 2011), and lower surface albedo (Akbari & Konopacki, 2005; Susca et al. 2011).

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Studies have found a correlation between increased green vegetation and reduction in city temperatures, indicating that urban temperatures could be controlled and mitigated through the use of urban vegetation (Susca et al. 2011). With a lack of space in the city for green areas, roof areas can provide the potential solution. Increases in green roofs within the city can provide a range of benefits including UHI effect reduction. The study by Susca et al. (2011) used a multi-scale approach and monitored air temperature and surface temperature of three different types of roofing systems in New York. The three types were: a black roof, a highly reflective roof and an extensive green roof. A 2°C difference in temperature was found between the most and least vegetated areas in New York (Susca et al. 2011). The results indicated a correlation between air temperature and vegetation abundance as was found in previous, similar studies (Petralli et al. 2006; Gaffin et al., 2008; Susca et al. 2011). The study highlighted the benefits of vegetation in UHI reduction. Research by Alexandri and Jones (2008) examined temperature decreases in urban canyons due to the implementation of green walls and green roofs in a variety of climates. Their results indicated that air temperature decreases at the roof level could be up to 26°C maximum and a 12.8°C daytime average. Inside the urban canyon decreases of up to 11.3°C was recorded with a daytime average of 9.1°C (Alexandri & Jones, 2008). In hotter and drier climates vegetation has a greater influence on the urban temperatures. The type of vegetation has the greatest influence on the temperature reduction compared to the effect of slope and orientation of the canyon. The greater the solar radiation a surface receives, the greater the temperature reduction achieved when the area is vegetated (Alexandri & Jones, 2008). In the canyon, wind velocities have no significant impact on the temperature variability.

5.5.5 Energy Efficiency Studies have attempted to investigate the effect of green roofs in temperature reduction of the roof surface membrane as well as regulation of the buildings temperature on warm and cool days. However, there is limited research on the actual quantification of energy savings after green roof installation (Niachou et al. 2011). Large-scale green surfaces in dense urban areas possess the potential to reduce energy consumption and contribute to urban temperature reduction. Many green urban areas are disappearing due to competition for land, and high property prices in cities (Niachou et al. 2011). Good thermal protection and insulation can greatly reduce thermal loads during summer (Niachou et al. 2011). Foliage and vegetation protects the building for direct solar radiation and can control temperatures and humidity of the indoor environment. The plants absorb a large amount of solar radiation through photosynthesis and evapotranspiration (Niachou et al. 2011). Green roofs offer protection from solar radiation contributing to passive cooling where the thermal fluctuation on the outer surface membrane is reduced. Through this process the thermal capacity in the spaces below the roof is increased allowing for cooling in summer and warming in Winter (Niachou et al. 2011). Due to this effect of green roofs, thermal losses can be reduced resulting in energy savings (Niachou et al. 2011).

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The study by Niachou et al. (2011) was conducted in two phases, the first where the indoor and outdoor temperatures were taken in buildings with green roofs installed, and during the second phase the thermal properties and energy savings were modelled using calculations and extrapolations (Niachou et al. 2011). Results indicated that the surface temperature of the green roof varied according to the type of vegetation used, with lower temperatures recorded in areas covered by thick, dark green vegetation and high in areas void of vegetation or with low vegetation cover (Niachou et al. 2011). The green roof contributed to controlling the air temperature inside the buildings, with reduced heat losses and reduced heating of the roof membrane in summer. Lower air temperatures were recorded inside buildings with the green roofs with the greatest energy savings calculated for non-insulated buildings with newly installed green roofs (Niachou et al. 2011). A study by Fioretti et al. (2010) examined the solar radiation through the vegetation as well as the thermal insulation performance of the green roof in Mediterranean climates. The study focused on two case studies which consisted of two fully monitored green roofs situated in public buildings. The green roof was shown to out perform the reference roof in terms of daily heat flow, therefore reducing the daily energy demand (Fioretti et al. 2010). There is still great need for full-scale experimental studies to aid urban planning practices. Research by Wong et al. (2003) quantified the energy savings for a commercial building in Singapore. Their findings indicated that the green roof installation on the five story commercial building resulted in 0.6-14.5% annual energy savings. Shrubs were found to be the most efficient in reducing energy consumption, as well as increased soil thickness and increased moisture content of the soil also contributed to energy savings (Wong et al. 2003).

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6. Results: Expert and Citizen Perception of the Current Situation

Table 6-1 indicates the results of the Q-Methodology. The table illustrates the greatest and least important barrier as indicated by each expert by sorting through the Q-Sort statements. It is important to note that there was one case of corresponding results with Tjerron Boxem from Amsterdam Rainproof and Friso Klapwijk from De Dak Dokters both indicating that the green roof subsidy is not persuasive enough for developers and this acts as the greatest barrier. There were conflicting results from Kasper Spaan and Caroline Uittenbroek, with Kasper Spaan indicating that citizens were not at all disengaged or disinterested in green roofs, while Caroline Uittenbroek viewed this as the greatest challenge to green roof implementation.

Table 6-1: Q-Methodology results indicating the greatest and least important barriers for each expert respondent.

Least Important Interviewee Field of Expertise Greatest Barrier Barrier Government does not Paulien Hartog Ecologist turned integral Citizens are interested but offer enough incentives water manager. lack the ‘know how’. (Waternet) for implementation. The maintenance is People are disengaged Kasper Spaan Aquatic deemed too costly and and disinterested in Ecologist/Toxicologist (Waternet) acts as a deterrent. getting involved. Incentives are not Tjerron Boxem The subsidy does not Urban Planner persuasive enough for appear to be effective. (Amsterdam Rainproof) developers. People are disengaged Issues with strong winds Caroline Uittenbroek Environmental Governance and disinterested in make feasibility in some (Utrecht University) Post Doctoral Researcher getting involved. areas difficult. Background in Human Roof rights and roof Homeowners are deterred Maarten de Laat Geography, now leads the usage put ground floor by the increased design Strategic Section of the residents off from (Stadgenoot) and construction cost. Sustainability Team contributing. Structural loading issues Incentives are not Friso Klapwijk in historic buildings Civil Engineer persuasive enough for make it too costly to (De Dak Dokters) developers. implement.

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-2

Table 6-2 is a data analysis table indicating the barriers as identified by the expert respondents in the semi-structured interviews. Each barrier has been coded, and the interviewees who mentioned them, cited. The most frequently cited barrier was the clear lack of policy (A7) in Amsterdam as mentioned by Van de Ven, 2016; Vergoesen, 2016; Klapwijk, 2016; and Uittenbroek, 2016. Three experts each referred to the following two barriers and these were the lack of knowledge (A2) and the mind-set of citizens (A4) living in Amsterdam. These three barriers were the most repeatedly mentioned by the expert respondents and one can deduce that they are commonly agreed upon.

Table 6-2: A Summary of the barriers identified for implementing green roofs in the city of Amsterdam

Code Barriers Key References

A1 Lack of scientific evidence is not convincing enough Stuurman.

A2 Lack of citizen knowledge Van de Ven;Uittenbroek; Hartog; Boxem.

A3 Lack of political support Uittenbroek.

A4 The Mind Set of Citizens Vergoesen; Van de Ven; Klapwijk.

A5 Multiple Ownership Spaan; Uittenbroek.

A6 Monumental Factor Spaan; Hartog.

A7 Lack of Policy Van de Ven; Vergoesen; Klapwijk; Uittenbroek.

A8 Costly Maintenance Van de Ven.

A9 Too Costly in Design and Construction De Laat

A10 Technical Roof Barriers Spaan; Van de Ven; Klapwijk.

6.1 Expert Opinion of the Green Infrastructure Potential in Amsterdam 6.1.1 Potential In Amsterdam there is great potential to be harnessed from green roofs indicating that there are very few currently implemented in the city. Research by Rooftop solutions indicated that there is a 12km2 area of rooftops available for green roofs (Spaan, 2016). Stadgenot has less than 5 green roofs in the city and many experts and citizens say they notice very few green roofs in the city, if any at all (De Laat, 2016). In Amsterdam there is still great progress to be made but the city has a solid basic infrastructure with the canals, water and parks. Amsterdam is a green city, in terms of vegetation, with trees introduced early into the historical layout due to their value in the public space (Spaan, 2016). Although many trees may be present in the city, it is

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-3 important to note that this does not constitute permeable space as the tree is usually planted in a small box surrounded by paving. The trees contribute other livability benefits besides surface water runoff reduction. The city lacks the smaller green roofs, pocket parks and squares, which are challenging to improve. In the inner city there is a complex situation of intensive use, street profiles and very little space to create extra storage. “It is in this area where we have to adopt a variety of small scale measures because space is limited and every drop truly counts” (Hartog, 2016). It has been acknowledged that the rain is a great challenge to the city, as models and forecasting have predicted it will rain harder and more often but the uncertainties make it very difficult to be precise in predictions. The results indicate a 10% precipitation increase, which significant and understood by specialists, but rather meaningless to citizens. “The peaks in rainfall are the greatest challenge to the city, because we live in a city designed on yesterdays weather and not on tomorrows weather” (Spaan, 2016). Due to technological advances cities have become more vulnerable and as a result we can learn from other disasters like hurricane Sandy which had extensive damage. In the Netherlands one assumes this cannot happen because of the moderate climate and the history of water management. It is vital for the government and citizens to recognize that a risk free society does not exist (as was once believed). This creates a unique and challenging situation where cities who face greater extremes in weather start to act quicker in challenging situations and often cities that become too comfortable can experience greater risk (Spaan, 2016). “The risks in the Netherlands still remain and if a rain event occurred like Copenhagen we could face billions of euros in damage, in a modern society where we are much more vulnerable than we once were, it is not a pretty or easy message” (Spaan, 2016). In the Netherlands the flatter the area, the more important the smaller difference in height. Currently it is difficult to work precisely, but the focus needs to be placed where the drops fall. “If we create a sponge like layer above the city then it will be easier to manage the water where it falls than when it runs off and accumulates elsewhere” (Spaan, 2016). With the statistics of a cloud burst occurring every 100 years one cannot justify enlarging the sewers to simply remain empty for 100 years. Amsterdam Rainproof tries to connect solutions underground and above ground in the public domain (Boxem, 2016). In general the attitude towards green roofs in Amsterdam seems positive, we have seen it does not need to be too expensive, it is aesthetically pleasing and encourages biodiversity (Spaan, 2016). Through the use of Rooftop Revolutions one hopes to make it more accessible and possible for the average citizen (Hartog, 2016). The city has provided 20 million euros in funding to invest in green rooftops in the city. The city is providing half the funding and the remaining cost is financed through crowd funding which will hopefully lead to improvement in the implementation process (Hartog, 2016). The greening of the city should create ecological connections, a more resilient, greener and liveable environment (Hartog, 2016). The contribution green roofs can make towards surface water runoff depends on the neighbourhood and the type of roof used. Sedum roofs do not retain 60% of the rainwater when the roof is saturated (Stuurman, 2016). The problem is that the effectiveness depends on the recent precipitation history, if the roof is saturated all the water simply runs off (Vergoesen, 2016). “The contribution depends on whether you add the drainage delay measures, if not it

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-4 doesn’t matter how thick the sedum is. If its 1m thick then you can store a lot. It’s only emptied by evaporation, which takes 2.5-3mm a day on average in Holland. So if you want to empty 13mm of rain it takes 10 days and that’s in Summer” (Vergoesen, 2016). For the majority of the year the sedum will largely be saturated in the Netherlands climate. Sedum green roofs are not ideal because the succulent plants stop evapotranspiration during dry and hot weather and only transpire at night. The purpose of the green roof is to ensure some degree of cooling (Vergoesen, 2016). Extensive roofs have gained in popularity and Frans Van de Ven (2016) conducted research on these roofs in terms of hydrological effects and cooling effects. He found that in both spheres the roofs effects was quite limited. While intensive roofs have a greater effectiveness in terms of hydrological effects it is important to be very careful with regards to the runoff. It can be loaded with nutrients and discharged into a country which has battled eutrophication for decades. A PhD student of Frans Van de Ven has just completed an article on green roofs and their performance in terms of heat stress, with results indicating a disappointing performance and limited effect (Van de Ven, 2016). Visually green roofs are a very valuable tool in practice, policy and society. “It is a similar concept to a rain barrel, 80l of water is not highly significant but from a psychological perspective the meaning is very important, it helps to make people aware of the fact that something needs to be done. There is an intensive green roof in Rotterdam where an agricultural project is taking place, a complex social structure has formed around this project and this value is absolutely a value for society” (Van de Ven, 2016). For the psychology of society green roofs are an important tool, however they need to be packaged in a wider context with other measures that contribute to greater water retention. “Amsterdam rainproof is only focusing on extreme rainfall and has a problem extending their scope to the other issues. I would say we have to address these issues in a more comprehensive way, it comes down to the fact that traditional sedum green roofs in terms of heat stress have a very limited effect” (Van de Ven, 2016). It is important to stress this comprehensive approach even in terms of flooding by extreme rainfall (Van de Ven, 2016). Green roofs are a small piece of the over-all solution puzzle. On average cities are comprised of 20% roof area and this cannot solve all the water problems (Vergoesen, 2016) De Dak Doktors are now producing food on rooftops at a pricing level of biological farming. Currently the efforts are not large scale but the technology does exist for a connection to a polder roof system. They have a small nursery inside the building where they grow plants to 3cm in height before transporting it to the roof where it will grow. They are currently implementing this at 4 restaurants in Amsterdam, but the business case remains challenging because food in Holland is inexpensive. The business case in Holland will likely never succeed, but in other cities such as Mexico City where there is an abundance of flat roofs and food is an import product there is potential for a business case to be built (Klapwijk, 2016).

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6.2 Expert Perception And Importance of Greatest Challenges Explained 6.2.1 Social Barriers

6.2.1.1 Lack of Evidence and Scientific Data Many citizens are not convinced of the benefits of a green roof and are unsure as to why they need it. The current data and current situation is deemed to be unconvincing and more evidence is needed to clearly illustrate why it is beneficial (Stuurman, 2016). Over time as more scientific data becomes available on the soft benefits of green roofs, citizen’s awareness will grow. It may be the case that more intense cloudbursts are needed to activate this awareness and get citizens to notice the current problem (Boxem, 2016). Many citizens often choose solar panels over the use of a green roof as solar panels are seen as more convincing, provide financial benefits and have the ability to produce energy that is visible in electricity usage reductions (Stuurman, 2016).

6.2.1.2 Lack of Knowledge One of the biggest challenges of implementation is the ‘know how’ factor where citizens are firstly unaware of their options and secondly do not know how to begin implementing solutions. This is an area where Waternet and Amsterdam Rainproof are focusing much of their effort (Hartog, 2016). “There is a tremendous lack of general knowledge and understanding of how the system works. This knowledge level is definitely hindering us in implementing these solutions.” (Van de Ven, 2016). The lack of awareness is one of the largest barriers to overcome, because it indicates that citizens do not consider a green roof, or secondly consider it but are unaware of their potential options and thirdly, if they would like to implement a green roof do not have the knowledge or access to the knowledge to start the process. It is a process that takes time and will take many more years to introduce the solutions to the world to make citizens and businesses aware of how the system is organized (Van de Ven, 2016). Respondents interviewed for this study were all highly educated, earning a high income and owning their homes. The lack of awareness among this highly educated group was very high, and thus the lack of awareness among groups with less education could be much greater. Caroline Uittenbroek (2016) said “I think a lot of people have a lower education are already not owning their home and just don’t have the access to the knowledge.”

6.2.1.3 Political Support The political support in Amsterdam for policies for mandatory green roof regulations is still growing. There is great potential for growth in political support and often it is assumed it will improve with time. “The political backing is growing, the strange thing is in many countries

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-6 you make many regulations and people agree. In the Netherlands it doesn’t work that way, first we need to improve awareness if there is a demand for it, then maybe it is possible. It sounds very easy, but implementation is far far more complex than one can imagine so we really are working on this. Nowhere in the Netherlands have we fully integrated this, although we have tried some parts” (Hartog, 2016). The combination of more political support and growing public pressure on the government makes it more likely that policy will be passed and finally implemented. Policy takes time to be approved and implemented and thus one can expect a very slow process with slow developments.

6.2.1.4 Mind Set A barrier to implementation lies in the mind-set of citizens, businesses, government and society in the Netherlands. People in the city should want the measure, see it as valuable to society and then slowly, over time other institutional barriers can be addressed. The desire and want for these measures needs to be present (Vergoesen, 2016). Green roofs are often proposed to businesses and housing corporations as a business case. This immediately causes a challenge, because in order for green roofs to see greater implementation there needs to be less focus on the business case and monetary terms. A green roof will not earn a business money and currently it in actuality costs the business money to implement. The mind-set needs to undergo a transition from one of seeing green roofs in monetary terms to one where they are seen for their numerous values (Van de Ven, 2016).

6.2.1.5 Multiple Ownership of Buildings Buildings with multiple apartment owners create added complexities for roof top construction and green roof implementation. Owners in a building could own their apartments or it could be a mix of homeowners and home renters (Spaan, 2016). Issues can arise in terms of who is interested and willing to contribute to a green roof which may not directly benefit them. ‘A lot of people don’t own their house in Amsterdam, that’s an issue, it is also not profitable for the big owners, it’s really a big investment and a lot of people are happy they get a home and are not even looking at the energy label or if its green’ (Uittenbroek, 2016).

6.2.2 Institutional Barriers

6.2.2.1 Monumental Factor Canal houses in the historic canal belt have historic value and thus it isn’t allowed to change the external appearance of these buildings or make changes to the roofing tiles by implementing a green roof. The policy is in place to protect these historic monuments and to ensure that the buildings in the canal belt maintain their uniform appearance. This factor makes

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-7 change in this area very challenging. There are some groups that support efforts to make monumental buildings green, but others argue this area should remain untouched. Due to these regulations major changes are difficult to achieve and often have lengthily approval processes. De Groene Grachten aims to provide the guidance and expertise to residents and homeowners as to which options are available to make their historical buildings more green. “Waternet is choosing to focus on other areas because there are more possibilities. The classic canal areas has a very finely meshed surface water system and thus the real storm water challenges aren’t that big there, it doesn’t mean that there aren’t any challenges there. Often the solutions are easily introduced in the public space by bringing the surface of the canal streets towards the water” (Spaan, 2016).

6.2.2.2 Lack of Policy Amsterdam is currently lacking any policy relating to mandatory green roof implementation in new or existing developments. The implementation is not mandated and thus voluntary implementation is slow and difficult to achieve. ‘Green roofs are progressing slowly and that’s because its not obligated. If you look at Rio de Janeiro if you want to build a new building it has to be water neutral and that’s obligated. In Holland it’s not obligated so everyone uses the cheapest solution’ (Vergoesen, 2016). The political signal and potential is interesting, the political value is present because it is an easy showcase to implement and citizens can see the efforts in the public domain. Despite this there is still no definite political support or public pressure (van de Ven, 2016). Hamburg underwent a large system change 4 years ago, the change was not a result of an incentive but rather the main trigger in changing the system was the idea of fairness. Citizens were dissatisfied that others who put more rainwater into the system paid the same in taxes. Community action groups took the government to court and won. The judge ruled that as long as the government did not change the system then they could not expect citizens to pay taxes anymore. Other cities in Germany followed suit and changed their system because they did not want to encounter the same issue. It took a large investment of 2 million euros to change the whole system. It was done in a very analytical way where every private plot in the city was mapped by flying over the city and detailed maps were drawn indicating exactly how much paved area was present in each property. There was also a special form to indicate where a household had a green roof, which would contribute to reduced taxes. The system worked in such a way that if you process half your rain water then you only pay half of the usual tariffs. The system has functioned well thus far, some people have received reduced tax fees while most people are in fact paying more. The problem with this system is it is very labour intensive and new maps need to be drawn every 5 years to keep up to date with city’s changes (Hartog, 2016). The Hamburg case is not directly applicable to Amsterdam because Hamburg has a higher elevation and there is more potential for infiltration. Currently the Alderman has agreed

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-8 to place a change in the wastewater processing in the decision-making. From the Waternet research it has been found that the analytical German way is not best suited for Amsterdam, due to the labour intensity, the dense areas in the city and the gardens with little infiltration. The research has indicated that it would be best to start with larger properties with large parking areas such as Ikea. These properties pay the same in water taxes as someone living on the first floor of an apartment in the city centre (Hartog, 2016). In the Netherlands, “if they really would like to stimulate these solutions the city could stress and emphasise it in their policy documents and in their building regulations. In many countries we have regulations which say any building should have a green roof unless….. So there are good examples around the world of this. Why use this step by step approach? It would be very helpful if the political decision makers took a more powerful step in trying to make green roofs obligatory unless you put solar panels, so you have to go for a roof with something going on. Not an empty space, a roof for harvesting, energy, rainwater whatever” (Van de Ven, 2016). In Amsterdam no one would want to push this legislation, it is often thought politically unwise to do so, and if you have an alderman who doesn’t believe in it he will not be willing to as it wont enhance his agenda. “For this first step to be put in place political support and powerful decisions are needed by political decision makers” (Uittenbroek, 2016). “Some people say the only way you get things done is through regulation. Currently extra rules are not favoured and politicians say leave it to the market. Then it becomes a question of the level, national or regional. It’s all in the big building level from The Hague. Implementing it at the national level takes time. At the local scale it could be done if you find the right key and can sell the story in a positive way, what it adds to the developer and the inhabitants and bring it positively” (Spaan, 2016). A significant step forward would be to have compulsory regulations for green roofs or green blue solutions in new developments. “The government could definitely do more, in every building permit there should be something said about green features or water or both of them” (Klapwijk, 2016). If large businesses and companies all were to get involved it would be a great step forward, but Amsterdam does not want to lose its big businesses and banks and thus they might pressure them into green measures but would not legally oblige implementation (Uittenbroek, 2016). Unfortunately the strategic people working at Amsterdam Rainproof have great ideas but “often become blocked with the people who are pragmatic and who have the budget and often these great ideas aren’t put into action” (Uittenbroek, 2016).

6.2.3 Economic Barriers

6.2.3.1 Too Expensive with Green Subsidy The housing corporations are of the opinion that implementing green roofs are simply too costly. The business case is not profitable for them, and until it is, it is very difficult to justify the implementation. An expert at Stadgenot explained that he was in charge of making the

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-9 business case for three green roofs on their buildings in Amsterdam. He explained that with the total cost of ownership, the investment and the maintenance for 50 years it would be twice as expensive as the installation of a normal roof (de Laat, 2016). It is a lot more costly and as a result Stadgenot cannot do it at a larger scale. The cost benefit analysis was sent to the board of directors for approval and I was informed that the green roofs were approved based on a subjective view of the value of the soft benefits. Stadgenot views the greatest challenge as the cost, followed by whether it is technically feasible (de Laat, 2016). “One of the problems besides the cost, higher maintenance and the investment is that we cannot earn it back by raising the rents” (de Laat, 2016). The value of the green roof is not yet appreciated; the risk in the maintenance often overrides this value (van de Ven, 2016). “The economic question and the business model for a private owner is quite difficult, if you add a green roof you will not see your money back for 20 years so either way it’s a bad business case or we didn’t have the right triggers in the business case yet. I think the big question is how can you make it a positive business case. It is not a question of value, if you look at a value map of a green roof you see a lot of upsides but the value is not yet connected to the revenue stream. If we can make that connection the right way then you will definitely see that 99% of the business cases will be positive” (Klapwijk, 2016). There is competition between green roofs and solar panels that can pay themselves off in 10 years, while green roofs do not offer these clear financial benefits. Often private companies or homeowners prefer the solar panel option as it clearly saves the building owner money. This financial benefit is a factor that is difficult to compete with (Uittenbroek, 2016).

6.2.4 Physical Barriers

6.2.4.1 Roof Issues “In the historical canal belt many roofs are the classic pitched roofs which are not the most suited to blue green roofs. Ideally blue green roofs work best on flat roofs” (Spaan, 2016). This combined with the monumental factor makes the inner city the most difficult to change because every change needs to go through an approval process (Boxem, 2016). “Building regulations in the Netherlands are not supporting green roofs and green blue solutions. Due to low rain and snow pack intensities we have very weak roof structures. Other countries and cities with earthquakes have more rigid structures that are often highly suited to green roofs.” (van de Ven, 2016). This creates technical barriers in the Netherlands because the overall regulation on how to design a roof is not efficient and not effective. Regulations need to be more future proof in terms of building a roof that is as strong as all the other floors (Klapwijk, 2016).

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6.3 Critiques of the Green Roof Subsidy The green roof subsidy was implemented at the start of the year after some changes and modifications from the earlier subsidy round. The changes aimed to streamline the subsidy, remove unnecessary complications and ensure some form of quality (Klapwij, 2016). It was removed because there was no climate adaptation attention and the three aldermen, water, planning and public space had other priorities and did not want to be in charge of its organization. The water sector focused on the economy of water, planning was focused on energy and mitigation measures and the aldermen were preoccupied with other matters requiring the budget and thus it was removed (Uittenbroek, 2016).

6.3.1 Does Not Ensure Quality It is important for government to invest in green infrastructure in the city, it is necessary and a communal responsibility that they have (Klapwijk, 2016). The green roof subsidy is viewed in a positive light but experts are quick to point out that it does not ensure the quality or effectiveness of the green roof (Stuurman, 2016). There needs to be a clear quality measurement for the subsidy (Klawijk, 2016). Two of the experts expressed that they had issues with subsidies and the connotation they carry and that the subsidy should rather be stopped with all the effort focused on promotion (Van de Ven, 2016; Klawijk, 2016). Often subsidies have the connotation of a left wing hobby and the focus should be less so on subsidising the process but rather creating the right investment. Van de Ven (2016) explained that he does not believe in subsidies because they are generally to the benefit of the constructor, he explained that there needs to be monitoring of the green roofs over the long term to ensure that they are adequately maintained. Some people might meet the requirements for the green roof subsidy but then no regular maintenance follows. Once the subsidy has been acquired checks and balances are needed to ensure good output quality (Van de Ven, 2016).

6.3.2 Benefits Water Authority The green roof subsidy is peculiar in the sense that it aims to solve the problems of the water authority while the green roof subsidy is paid for by the municipality and the water authority does not contribute towards this. “It might be because the city wants to improve the liveability and this is the reason for the city to subsidize and stimulate the development while the primary beneficiary doesn’t pay anything for this” (Van de Ven, 2016). Some argue that if it is really benefitting the water board then they should lower their taxes, but this will result in less income, thus supplying less people and the water board will not be willing to do that (Vergoesen, 2016).

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6.3.3 Mobilizes Non-Target Group It is criticised that the subsidy and the compensation money is given to the top 5% of citizens and companies who have the interest in green roofs and green technologies and this is the group who would implement the green roof despite a subsidy. It is argued that you do not mobilize the target group you would like to have, but rather the group of citizens already interested in green objectives (Uittenbroek, 2016).

6.3.4 Too Complex “The first subsidy round 2010-2013/2014 had some issues in it. It was unnecessarily complex with a lot of papers and a lot of checks and balances and it was also a stop-go process. There was no horizon of the fund for three years. The new subsidy fund is way better in terms of a three-year horizon every quarter and you are aware of the amount of money available if you apply” (Klapwijk, 2016). According to Paulien Hartog (2016) in the past the green roof subsidy was not effective, it was too complex for people, they had too little knowledge and the ‘know how’ was a barrier. She believes in the rooftop revolution concept and crowd sourcing which can make the subsidy more attractive, with the former subsidy providing the necessary experience” (Hartog, 2016).

6.4 Potential Solutions

6.4.1 The Right Dialogue Currently Waternet is working towards getting blue green roof regulations into policy to make a more ‘sponge like’ and permeable city. Waternet has recognized and adopted the more modern approach of being proactive, engaging the citizens and finding the correct dialogue. In the past one waited for the citizens to approach Waternet in a more passive style. Waternet is focused on creating a positive dialogue with stakeholders and being active in their approach in engaging citizens by holding events, distributing fliers and contacting the stakeholders themselves (Spaan, 2016).

6.4.2 Deregulation Friso Kalpwijk (2016) explained how the complicated and unnecessary green roof and building regulations add further complications often acting as a deterrent for citizens who wanted to implement green roofs. If a citizen has a small roof surface for a green roof and would like it to function as a green space as well as a recreational area, the first 2m at the front sides needs to be left clear, as well as 1m from either side of the neigbours walls. If you have a small starting area, this leaves very little space to create a green roof with people opting for a recreational roof terrace area rather than making it green with little or no space for recreation. The city needs to deregulate this or make it less constraining, then one will see completely improved

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-12 results (Klapwijk, 2016).

6.4.3 Small Scale Solution Measurement System “Our philosophy from the rainproof programme is that every drop counts, because we think that the solution to making the city more robust or water sensitive is through a small solution measurement system. That’s where the green infrastructure especially in the private environment can help a lot” (Spaan, 2016). To improve surface water runoff and make the system more permeable and robust one needs to focus on a network of finely meshed small- scale instruments. This network of small instruments can have a powerful effect (Spaan, 2016). It is important for solutions to be made to measure for example rain barrels, extended rain pipe systems and various infiltration techniques. One needs to consider where we want the water to go and then to try control the flow (Spaan, 2016). Frans Van de Ven (2016) does not see it as a major issue that monumental buildings cannot have green roofs because the effectiveness there would be very limited and the true effectiveness is the result of a combination of solutions. It is important to think about enhanced potential when combining solutions for example the combination of a green roof and a water harvesting tank (Van de Ven, 2016). “To have an effect these small scale solutions need to be expanded on a larger scale, but of course anything helps and running a marathon starts with the first step” (Vergoesen, 2016).

6.4.4 An Improved Subsidization System Waternet focused efforts on finding the correct dialogue with the municipality in order to revise the subsidization system which needed various factors reconsidered and improved. It was arranged that the municipality make stipulations with regard to water retention. If the roof retains more water than a traditional green roof then it should receive greater subsidization. This was an important step to encourage implementation of blue green roofs and more intensive green roofs (Spaan, 2016).

6.4.5 Showcase Projects Large-scale showcase projects play an important role in gaining media attention as well as citizen interest. These types of projects show citizens and companies the potential solutions which are possible. These innovative example projects should provide convincing evidence that can potentially persuade companies. The media attention helps to illustrate to companies the positive effect pilot projects can have on a company’s public image (Stuurman, 2016). Germany, France and Belgium are ahead in this process due to their regulations for new and existing buildings with projects widely noticed by their citizens and media (Spaan, 2016).

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6.4.6 Crowd-Funding Start Up: Rooftop Revolutions Experts at Waternet and Amsterdam Rainproof have expressed that they believe that Rooftop Revolutions might be able to achieve enhanced implementation of green roofs in Amsterdam (Hartog, Spaan, 2016). The crowd funding initiative of Rooftop Revolutions should help provide the finances for a green roof in the community, be more transparent and transcend the barriers from complications of roofs with different owners. The initiative can add value to surrounding real estate with involvement and collaborating though social media. The platform also ensures that the necessary guidance and expertize will be provided for by a small group of advisors at Waternet (Spaan, 2016).

6.4.7 Certifications The BREAM certification is mainly focused on materialization and energy use and one can build an excellent BREAM building without green measures or water harvesting. Currently there are efforts to try and influence the BREAM certification to add a green performance and water performance indicator, but this will still take time. This certification focuses on new buildings while a lot of focus needs to turn to existing buildings (Klapwijk, 2016).

6.4.8 Ideological Shift with More Evidence With more convincing scientific evidence more people become convinced by the green roof benefits and concept, with ideals shifting over time (Stuurman, 2016). The mind set of a green roof only being viewed as a business case could too be shifted with more applications, more experience and familiarity with the technology (Van de Ven, 2016). Great efforts are being made to engage the citizens and try to get them thinking about climate robustness in their city (Boxem, 2016). We have seen a shift in companies who are enhancing their positive public image through sustainable offices in the South Axis (Boxem, 2016).

6.4.9 Focus on Intensive Roofs There should be greater focus on encouraging the use of intensive green roofs over the use of extensive green roofs. Intensive green roofs have a far greater potential in terms of water retention than the shallow substrate layer of the extensive green roofs. Although any green roof implementation is a positive step, intensive green roofs should be encouraged (Van de Ven, 2016). Intensive green roofs can cause eutrophication so they should be applied with careful consideration (Van de Ven, 2016).

6.4.10 The Right Marketing Amsterdam Rainproof is working with the retail companies to make the city’s inhabitants more aware of rainproof solutions and to convince them it is important and effective to buy rainproof products. Tjerron Boxem is working with Intratuin and Garden Branch Netherlands (develops

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-14 products) to form these promotions and products. The garden center in Watergrafsmeer has a large display on how one can rainproof their garden and the personnel are also trained to assist and answer these questions (Hartog, 2016). The green roof kits and packages sold in nurseries are an important development for the marketing of the tool (Van de Ven, 2016). Government should create a 5, 10 or 20 year green infrastructure program and work consistently on this with focus in marketing and awareness of solutions for existing buildings (Klapwijk, 2016).

6.4.11 Cheaper Technology The greatest barrier to convincing the municipality, businesses and citizens still remains the business case (Boxem, 2016). Greater incentives and improved, cheaper technology could have a large impact. The greatest barrier for Stadgenot is the cost of installation and maintenance. If costs were reduced it could provide long-term stability because with changing government and political motivations the subsidy could be removed (De Laat. 2016). Green roof maintenance does cost at least twice as much as a conventional roof but the soft benefits, which are difficult to monetize, are endless (Boxem, 2016). One needs to make this business case to the municipality, including all the soft benefits, illustrating that these difficult to monetize benefits do outweigh the added costs of maintenance (Boxem, 2016). Through the Rooftop Revolution concept it is hoped that the crowd-sourcing model can improve the business case and finance complexities (Boxem, 2016).

6.4.12 Start with Younger Generations It is important to start with the younger generations and allow them to apply a small project which allows them to think about the rainproof processes. Their minds are still fresh and their excitement will allow them to share these new ideas with their parents and slowly get more families involved (Vergoesen, 2016). This year alone 20 school yards will be greened by the municipality and Waternet aims to not only make these areas green but make the city think about the areas in green blue terms. The area has a very high educational value for the children and allows the children to think about green areas and rainwater (Hartog, 2016). The idea of separating ones waste took two generations to become a common practice. This is an example of something that has become a standard but took at least two generations to get to this position. Starting with the younger generations allows for the younger generation to grow up with this as a standardized practice (Vergoesen, 2016).

6.4.13 Changing Infrastructure at the Right Moment When the city is scheduled for repaving or the electrical company needs to access their cables this is the moment when the city can be improved in a rainproof way. The city has its own procedures for closing the street to its original construction. This is the opportune moment to make some small changes and implement an improved design (Boxem, 2016). A great improvement can be seen by applying hollow roads and collecting water and letting it infiltrate

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-15 slowly or drain slowly in a similar way to that of green roofs (Vergoesen, 2016). “If you look at investment plans for the city, billions of euros in Amsterdam alone are shelved into sewerage systems which is crazy as it’s a single function concrete pipe underneath the ground to transport rainwater. Its not a waste stream but a resource so if you change the paradigm and look at all the euros used to replace and enlarge the sewerage systems, one should try change the financial streams from investing into a single use concrete pipes towards investing in green infrastructure” (Klapwijk, 2016).

6.4.14 Mainstreaming This years current focus of Waternet and Amsterdam Rainproof is to get rainproof thinking into municipalities and governmental agencies (Hartog, 2016). More mainstreaming is needed in the public domain; if they have to redesign or redevelop a street area there should be certain guidelines to adhere to including that the street should be able to process 40mm-60mm of showers. The goal is mainstream all processes in the city with rainproof considerations at every stage of a project as well as clearly outlined in policy (Boxem, 2016). Waternet is currently working on a cost benefit analysis (economical demonstration) where they aim to see the potential benefits of mainstreaming in the city, broad scale benefits and their cost. These benefits are all soft, difficult to quantify, qualitative benefits that are displayed in an illustration (Hartog, 2016).

6.4.15 Insurance Scheme and Tax Scheme Waternet is currently working on an insurance fee reduction with insurance companies in Amsterdam, but this process is still in the exploratory stages. Insurance usually fixes an issue in the same manner as it was before the damage. They believe that the insurance company should learn from the given information and fix it in a manner that the same water damage cannot occur again (Hartog, 2016). The scheme with insurance companies aims to get an insurance fee reduction with added safety and rainproof features. The business case and risk analysis is currently being created to examine whether the companies can create an incentive (Boxem, 2016). The insurance fee reduction is criticized because one person implementing rainproof measures will not stop their repeated damage if neighbours have no rainproof measures (Boxem, 2016). Waternet is currently investigating changing the tax scheme for water. If one implements a rain proof measure: green roof, rain barrel, water garden or any measure that could improve the collection and retention of water, then one could receive a tax reduction on the water fee (Boxem, 2016) The options are currently being investigated, but Friso Klapwijk (2016) argues that the reduced water tax will be as little as 10 euros per household, and will not act as a real incentive.

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-16

6.4.16 Policy Waternet is currently working on a water neutral envelope where if one wants to develop a building then there is an envelope that one cannot make a rainwater connection to the sewer system in the public space. This ensures that all new buildings and redevelopments will be water neutral as well as use various innovative green methods without connecting to the public sewerage system. Every building gets demolished every 80-100 years and then redeveloped; it is at this moment that one needs to get the water neutral element in place. One will not see an effect in the immediate short-term, this process will take time (Boxem, 2016).

6.5 Citizen Perspectives 6.5.1 Perception of Green Roofs From the citizens interviewed there was a very clear positive view of green roofs in Amsterdam and a viewpoint that they were very beneficial to the liveability of the city (Swagerman, 2016; Fontijn, 2016; Medea Csapo, 2016; Dragoudaki, 2016; De Ritis, 2016). The same interviewees expressed that they believed there was too little green infrastructure in Amsterdam, and that more could always be done to improve this (Swagerman, 2016; Fontijn, 2016; Medea Csapo, 2016; Dragoudaki, 2016; De Ritis, 2016). Other interviewees said they did not have enough information or that there was too little promotion and awareness created surrounding green roofs in Amsterdam and thus did not have an opinion on green roofs in Amsterdam (Swagerman, 2016; Oosterhout, 2016). Interviewees explained that the majority of roofs in the cities are either wooden decking or paving for convenience purposes as this requires minimal maintenance (Fontijn, 2016; Medea Csapo, 2016; Oosterhout, 2016). An interviewee living in the Eastern Docklands has a free standing house and explained how he had considered constructing a green roof but chose solar panels as he believes they are better for the environment and pay themselves back within 10 years (Tjoe Nij, 2016). Other interviewees were of the same viewpoint that they had not considered a green roof but had briefly enquired about solar panels. The process was quickly cut short as the monumental regulations would not allow it (Fontijn, 2016; Dragoudaki, 2016). These interviewees were of the opinion that solar panels would be more beneficial for the environment (Tjoe Nij, 2016; Fontijn, 2016; Dragoudaki, 2016). The remaining interviewees had never considered a green roof as an option, either due to spatial issues or they wanted the area for recreational purposes (Swagerman, 2016; Medea Csapo, 2016; Oosterhout, 2016; De Ritis, 2016).

6.5.2 Public Awareness From the interviews with the citizens the public awareness regarding green roofs in Amsterdam appears to be incredibly low despite many promotional campaigns and organizations. All

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-17 except one interviewee was aware of the green roof subsidy in Amsterdam but was still unclear on the specifics (Dragoudaki, 2016). These are residents who are well-educated homeowners who have been living in Amsterdam for at least the last 10 years. Every interviewee except for one was not aware of the various green roof organizations and companies in Amsterdam such as De Groene Grachten, De Dak Dokters, Rooftop Revolutions and De Gezonde Stad. The only interviewee who was aware of them had heard of De Dak Dokters and De Gezonde Stad but had not considered a green roof (Oosterhout, 2016). The interviewees expressed how they did not have any friends with green roofs, know of many green roofs in Amsterdam, or have not seen many in the city (Tjoe Nij, 2016; Medea Csapo, 2016; Dragoudaki, 2016; Oosterhout, 2016; De Ritis, 2016). When asked if the interviewees knew who to contact or where to begin when implementing a green roof they all except one interviewee expressed that they did not know where to start. Some interviewees explained that they would search on the Internet or call some experts (Medea Csapo, 2016; De Ritis, 2016). The self-builder living in the Eastern Docklands was aware that green roof kits were quite readily available and easy to install (Tjoe Nij, 2016).

6.5.3 Water Issues All the interviewees expressed how they have had various water damage issues, except for the new home built by the self-builder in the Eastern Docklands who has had no issues to date (Tjoe Nij, 2016). Many noted that rainfall has become more severe over the years with various major cloudbursts causing great damage (Fontijn, 2016; Dragoudaki, 2016; Oosterhout, 2016; De Ritis, 2016). Some have water damage in the walls, or issues with the roof terrace waterproofing and thus water damage on the ceiling (Swagerman, 2016). Damage is especially severe for the top floors of one respondents canal house after heavy rains and this is said to happen periodically (Fontijn, 2016). A woman living in the Oud-Zuid had severe damage after heavy rains three years ago, the sewers were filled to capacity and the ground floor of her apartment became flooded. Many people were away and neighbours returned to their furniture floating in their apartment (Dragoudaki, 2016). Her husband called Waternet who explained that there was currently nothing they could do because they had received over 400 phone calls with similar issues (Dragoudaki, 2016). This was an intense cloudburst and many streets and apartments were flooded.

6.5.4 Amsterdam as a Green City Citizens were asked to give their perspectives on whether they viewed Amsterdam as a green city. Opinions were mixed. A woman living in Overtoom said there was no city quite like Amsterdam. She explained that for a city, Amsterdam is incredibly green because it is still qualifies as a city but still has many green spaces (De Ritis, 2016). A woman living in the Kinkerbuurt explained that she thought Amsterdam still had great potential to become much

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 6-18 greener and that it seemed as though the green roof trend has not quite caught on in Amsterdam as it has in other cities (Medea Csapo, 2016). A woman living on the Herengracht explained that she thought that Amsterdam was not green enough and there are many areas that could still be improved (Fontijn, 2016). A respondent living in Oud-Zuid explained that he thought the city was partly green and that it was much greener than many other cities. He believed it is greener than London which is not a very green city (Oosterhout, 2016).

Masters Thesis: Green Infrastructure in Amsterdam Results: Expert and Citizen Perception of the Current Situation 7-1

7. Discussion

7.1 Main Findings 7.1.1 Great Under Realization of Permeable Green Infrastructures in Amsterdam Whether Amsterdam is considered a green city is a subjective question with each citizen having a highly varied opinion. Amsterdam in its historic design had planners who saw the value in tree lined streets in the public space, but for the purpose of this study the connection must be made between green infrastructure and the relation to surface water runoff. Many tree-lined streets have trees placed in paved boxes contributing little permeable space for surface water runoff reduction. The trees provide a host of other positive benefits but they do not relate to retention and stormwater reduction. The calculations made in this study indicate that Amsterdam has approximately 14,9% green permeable space in the city and an area of 12km2 of available rooftops for green roof implementation (Spaan, 2016). The green permeable area surveyed did not account for potential soil drainage issues and wet spots and thus the approximate value of permeable green space could ultimately be less than 14,9% of the study area. This indicates a great under realization of permeable green infrastructures in the city of Amsterdam with great potential for improvements that can make significant contributions to surface water runoff reduction.

7.1.2 Greatest Barriers in Amsterdam The greatest barriers as expressed by the expert respondents in this study were the green roof installation and maintenance cost which is more than twice the cost of a traditional roof even when including the green roof subsidy, the lack of ‘know how’ of the citizens, the lack of policy, the added technical measures to ensure safe and approved installation, lack of concrete scientific data to make the case more convincing, and lastly benefits that are difficult to monetize and of subjective value in the business case. These barriers were identified in the expert semi-structured interviews as well as confirmed in the Q-Methodology.

7.1.3 Lack of Existing Policy Although the city of Amsterdam has placed great emphasis on the climate robust measures and trying to enhance rainproof features there is still a clear lack of policy relating to green infrastructure implementation. This is a major barrier to increasing and expanding implementation in the private space, in company and privately owned business buildings and developments. The majority of housing in the city is owned by housing corporations accounting for much of the cities roof space. Without any existing policy mandating that new developments and existing buildings implement green infrastructure, it remains completely

Masters Thesis: Green Infrastructure in Amsterdam Discussion 7-2 voluntary and at the slow pace of personal interest and mind-set shifts. The lack of policy places Amsterdam at a disadvantage compared to other cities in Europe that have strong policy and have taken a more proactive approach (e.g. Hamburg). Recognition by political parties of the importance of green infrastructure promotion can help to further the policy agenda. Currently the only existing policy instrument is the green roof subsidy with the previous round proving ineffective. The changes and updates to the terms and conditions have not been implemented long enough to determine whether this subsidy round is more effective. The remaining potential policy instruments are an insurance fee reduction and water tax scheme which are currently in development with their success and implementation remaining to be seen.

7.1.4 Mismatch Between Policy Instruments and Barriers There is a clear mismatch between the existing policy instrument of the green roof subsidy and the most important barriers as identified in this study. The currently implemented policy instrument and the two policy instruments in development (tax scheme and insurance fee reduction) only attempt to address the financial barrier of green infrastructure implementation with no focus on issues regarding technical measures, unnecessary regulations, improving scientific data, and improving citizen ‘know-how’ and awareness. Although Waternet and Amsterdam Rainproof have placed great emphasis on improving citizen awareness, citizen awareness regarding green infrastructure and the system still remains very low. Much can still be done to deregulate the green roof implementation process, promote green roof research, and to regulate roof-building requirements to be a sufficient strength for green roof installation. Although the cost of installation and maintenance is a great barrier to implementation the green roof subsidy has its pitfalls. It does not ensure quality of the roof and regular maintenance; it also mobilizes the group of citizens who may already be inclined towards sustainable measures (Uittenbroek, 2016). There is still great potential for government to focus on other policy measures to deregulate the roof implementation process, regulate roof requirements and create long-term educational programs that can lead to systemic mind set shifts.

7.1.5 Extreme Lack of Citizen Awareness Although experts mentioned that citizen ‘know-how was a barrier to green roof implementation I believe there is a much greater gap in knowledge between what Waternet and Amsterdam Rainproof consider the level of awareness to be. They are aware this is a major challenge, but awareness may be much lower than they may have anticipated. Citizens are extremely unaware of available options, green roofs, Amsterdam Rainproof and where to begin with such a project. Unless the citizen was actively participating in the field and had a keen interest, they largely had very little awareness of green roofs in Amsterdam and the rainproof concept. This lack of awareness and ‘know-how’ proved debilitating in the implementation process with a clear lack of understanding as to how the system operates. Long-term generational change will only be

Masters Thesis: Green Infrastructure in Amsterdam Discussion 7-3 achieved through educational improvements and promotional campaigns to change the way of thinking.

7.2 Results in Relation to Theory The lens of implementation theory was used to examine the relationship between the structure of the institution through which public officials and citizens interact and the outcomes of their interactions (Jackson, 2001). Implementation theory was used to examine how policy and policy instruments create conditions for conceptualizing policy directives (Pallfy, 2010). In the case of Amsterdam there is a lack of dominant policy with a single policy instrument of the green roof subsidy, which was introduced, removed and reintroduced this year. The green roof subsidy has previously proved largely ineffective with many criticisms detailed in 6.3 of the results section. The subsidy has subsequently been redeveloped and introduced but it is too premature to conclude on the second round of subsidies effectiveness. The previous round has proved largely ineffective, as there is a great under realization of green infrastructure in the city of Amsterdam as detailed in Chapter 4 Section 3. The green roof subsidy is a top-down policy instrument offered by government in Amsterdam, but the importance lies in the way various organizations and implementers shape the policy in design, redesign and outcome. The top-down and bottom-up perspective was both applied to this study as top-downers focus on the effectiveness of governmental programs, and the way in which public officials can constrain the actions of target groups (Sabatier, 1986) while bottom-uppers are not concerned with the policy decision, but rather with the strategies of actors that are concerned with a particular policy issue and understanding the actor interaction (Sabatier, 1986). The top-down perspective of this study examined the effectiveness of the green roof subsidy and its accompanying regulations that control implementers, while the bottom-up perspective examined the organizations and actors that interacted to achieve implementation.

7.2.1 Top-Down Implementation Government in Amsterdam attempts to control the behaviour of the implementers of green infrastructure by offering the green roof subsidy as an incentive (De Gruyter et al. 2015). This approach is applicable to the case of Amsterdam but is complicated by the lack of dominant policy (Sabatier, 1986). In the case of Amsterdam the first subsidy round can only be judged for effectiveness as the second round has only been implemented for a short length of time. The subsidy has consisted of two rounds the first highly complex, with many unnecessary regulations and did not ensure quality of the green roof. The second round of the subsidy is more streamlined and has accounted for ensuring a higher quality of structure. The first round of subsidies proved largely ineffective in achieving the objectives, with the output of the policy instrument influenced by the implementers access to knowledge and resources to apply for this

Masters Thesis: Green Infrastructure in Amsterdam Discussion 7-4 subsidy. The subsidy however does not ensure long term, quality maintenance leading to output green roofs of varying quality (Sabatier, 1986). The framework formulated by Sabatier and Mazmanian (1981) indicated the necessary conditions for effective policy implementation and in the case of Amsterdam the condition of clear and consistent objectives and adequate causal theory are met, however there is no legal mandating policy to enhance compliance, support from politicians and the public is still lacking and socio-economic conditions which influence support are currently volatile.

7.2.2 Bottom-Up Implementation The Bottom-up implementation perspective allows one to identify the variety of actors involved in green roof implementation and their strategies used (Sabatier, 1986). The action and service delivery shapes policy outcomes more than the actual design of the policy (Sabatier, 1986). This approach focuses on the local implementation structures and organizations and their dynamics. In the case study of Amsterdam, Waternet, Amsterdam Rainproof, De Groene Grachten, De Dak Dokters, De Gezonde Stad and Rooftop Revolution involve multiple actors for green roof implementation. Waternet and Amsterdam Rainproof focus on rainproof awareness in the city and aiding active citizens in ideas and events they need facilitated. De Groene Grachten and De Gezonde Stad are non-profit organizations which aim to offer solutions and guidance for citizens who would like to implement sustainable solutions on their property which also helps to improve the liveability of the city. De Dak Dokters is a private company which provides all the necessary services for citizens and companies to design, process and implement a green roof project. Rooftop Revolution is a new project created by Waternet to provide crowd funding and guidance from experts at Waternet to help implement community green infrastructure projects. Implementation most often occurs as a result of active, interested citizens who show initiative, or active citizens partnering with an organization for guidance.

7.2.3 In Relation to Policy Instruments The green roof subsidy is a policy instrument used by the city of Amsterdam as a technique governmental authorities use to display their power, garner support and create social change (Bemelmans-Videc et al. 1998). Often effective programs use a unique mix of policy instruments to achieve optimal effectiveness but in this case this is the only implemented policy instrument by the city. There have been promotional campaigns by Amsterdam Rainproof but these have not been used in conjunction with the subsidy as a combination method. It is essential that that these tools are carefully selected to ensure goals are achieved but as indicated in the main findings, the singular implemented policy instrument only addresses the financial barrier and does not even fully address this costing issue. Even when including the green roof

Masters Thesis: Green Infrastructure in Amsterdam Discussion 7-5 subsidy the cost of installation and long-term maintenance is twice as costly thus creating a difficult business case.

7.2.4 The Choice Versus Resource Approach In the case of Amsterdam the approach used is from the perspective based on a situation the government has already decided upon and the categories are of the resources the government can use i.e. funds for the green roof subsidy (Bemelmans-Videc et al. 1998). In approaching this public problem of lack of implementation of permeable green infrastructures, government has four broad choices: (1) allow market mechanisms to act on their own, (2) use structured options created by government, (3) use biased options, such as incentives and deterrents so that individuals can be guided voluntarily or (4) use direct control through regulation. Through the use of biased options, the government can guide citizens to act in line with public policy (Anderson, 1977). In Amsterdam there is no dominant, mandatory policy requiring green infrastructure implementation in new or existing developments and thus there is no direct control through regulation. The city of Amsterdam uses biased options in the form of incentives to guide citizen’s actions in a voluntary manner (Bemelmans-Videc et al. 1998). The subsidy is a voluntary incentive that citizens apply for, thus there is no degree of compulsion enforced by government. The green roof subsidy is a policy instrument that caries an inherent assumption that it is an inducement and that the capacity exists to achieve what is required but is more readily achieved with the monetary incentives (McDonnel & Elmore, 1987). Mandated green roof policy would assume that action is required regardless of capacity and would not occur without the desired frequency without this policy McDonnel & Elmore, 1987). I argue that mandated green roof policy is necessary in new developments to ensure that the frequency of green roof implementation is guaranteed.

7.3 Limitations of the Study Green roof research is still its early stages and there is a clear lack of conclusive, significant data which accurately quantifies the benefits. Concrete scientific data could provide great support for the currently lacking business case. I call for more concrete scientific data to support and illustrate the wide variety of significant benefits green roofs offer in order to help support and validate my research. Waternet and Amsterdam Rainproof have access to complex and costly models which illustrate the exact problem wet spots in the city of Amsterdam. This data is not made accessible to researchers, as there are concerns as to the effects it could have on housing prices. This data would have provided much insight for my research but there appears to be a large amount of data that is not shared. This research could have gained from interviews and contact with Gemeente Amterdam, however contact could not be made as they have a variety of other priorities at this time. The cities perspective would have contributed a different and interesting view point to this study. Reliable research can always benefit from a larger sample size to ensure fair representation and accurate results. Although my sample size

Masters Thesis: Green Infrastructure in Amsterdam Discussion 7-6 is large for the time constraints, extra respondents can add greater reliability to results of the research. The Q-Methodology encountered a number of issues as it is a methodology still in development. The Q-Sort statements are very difficult to perfect and ensure that they are not biased, one needs to ensure that each factor is equally represented. The distribution chosen is a subjective choice made by the researcher that is difficult to justify. Respondents either responded extremely positively to the Q-Methodology or really disliked it and immediately had a negative disposition towards the method. This could influence the effort and focus put into the Q-Sort. Some respondents sorted the statements in 15 minutes while others took much longer, closer to 35 minutes, which could indicate their interest or enthusiasm. This is a factor that is impossible to measure or accurately represent in the results. The results of the Q-Sort were rather ambiguous and insignificant making it a difficult and subjective decision to determine whether one should include them in the final dissertation.

7.4 Scientific Relevance This study makes a contribution to the field of green infrastructure implementation research in a European city. Previous work by Zhang et al. (2012) studied implementation barriers of green roofs in existing buildings in Hong Kong. Green roofs have been identified as one of the best possible solutions for Hong Kong’s existing pollution problem (Zhang et al. 2012). Their study found that there was a lack of incentives from government and a failure to promote green infrastructure (Zhang et al. 2012). There are currently no other public studies or research available regarding implementation challenges in Amsterdam and other European cities. Governments have shifted implementation policies to promote green urban space, green roofs and green infrastructure but challenges in the process still remain. In Amsterdam Waternet and Amsterdam Rainproof have conducted a number of promotional campaigns, however citizen awareness remains low. The subsidy provided as an incentive is deemed insufficient as the costs of implementation and maintenance still remain high. A large number of studies have focused on experiments relating to water, biodiversity, UHI reduction and energy savings in buildings however, results remain limited and contradictory. More quantitative, reliable research is needed to ensure that the values and benefits case becomes more convincing for implementation. More context specific research is needed on other European cities and their implementation challenges. It is hoped that this scientific research can aid the municipality of Amsterdam in future decision making and in promoting the case for mandated policy.

7.5 Opportunities for Further Research Interesting opportunities for further research include conducting extensive survey research of citizens living in Amsterdam to get a large, highly representative set of data for reliable results. Extensive research can provide accurate public citizen data which can be publically accessible

Masters Thesis: Green Infrastructure in Amsterdam Discussion 7-7 as well as of use to Gemeente Amsterdam. Interesting insights could be gained by conducting comparison research between Amsterdam and another European city which has seen wider green infrastructure implementation success. A comparison could yield insights into critical success factors that could potentially enhance Amsterdam’s policy and implementation process.

Masters Thesis: Green Infrastructure in Amsterdam Discussion 8-1

8. Concluding Remarks

Through the research conducted in this study I am able to form some cautious conclusions from the results of the research. This is not without a very clear awareness of the limitations in this study as outlined in the discussion section. There is a lack of permeable green infrastructure in the city, with great potential for expansion. There is still much progress to be made, but the foundation of the basic, historical infrastructure and design has placed great emphasis on the importance of green areas in the public space. An important distinction should be made between trees in planters that do not offer permeable space or rainproof features compared to that of open permeable green infrastructure that retains water. For the purpose of this research the focus has been placed on making the city robust, permeable and climate proof. The greatest implementation barriers proved to be the cost of installation and maintenance, lack of ‘know how’, added technical measures for implementation, and benefits that were difficult to monetize. There is a clear lack of policy mandating green infrastructure implementation in new or existing developments which has resulted in little implementation in the city. The policy instrument of a green roof subsidy has in the past proved ineffective and unnecessarily complex. Experts have many critiques regarding the subsidy and its unsustainability as outlined in the results section. The green roof subsidy only attempts to address the financial barrier of the cost of installation and does not attempt to address the remaining social, institutional and educational barriers. There is a clear mismatch between the policy instruments from the city and the barriers indicated in this study. The research indicated that citizens were under aware regarding green roofs, rainproof measures and the subsidy, proving my hypothesis correct that one of the most important barriers to implementation is the lack of ‘know how’ of citizens. Even greater focus needs to be placed on improving public awareness through long- term school projects, which focus on the younger generations. Public and political support needs to encourage the implementation of mandating policy, which is critical in expanding implementation. Political support is crucial for policy to be passed and to suit the agendas of politicians. Expansion of green infrastructure networks will take time as generations change and as the scientific benefits become accurately and concretely quantified furthering support for the political agenda. Green roof regulations should be relaxed in order to prevent the reduction of available roof space for green roof implementation. Building regulations in the Netherlands should be improved so that roofs have the same structural requirements as first and second floors. The low snow pack intensities in the Netherlands results in many roof structures that are too weak for implementation and need added structural measures. Researchers and experts have indicated that green roofs cannot be viewed as the only mitigation measure, but efforts should rather be focused on watershed scale stormwater management (Berndtsson, 2010). Results indicate that green roofs show potential in managing stormwater from small rainfall events in highly urbanized and developed areas (Berndtsson, 2010). The green roof is often viewed in idealistic terms as the solution to solving urban

Masters Thesis: Green Infrastructure in Amsterdam Concluding Remarks 8-2 stormwater problems. Van de Ven (2016) and Vergoesen (2016) indicated the importance of making the distinction between extensive and intensive roofs and their effectiveness. Extensive green roofs have limited runoff reduction effects during intense, lengthily storms or if they are currently saturated. Intensive green roofs have a much greater stormwater runoff reduction effect but due to the structural requirements are not implemented to the same extent and they also carry risks of added eutrophication. Although the implementation of extensive green roofs may have little effectiveness on stormwater runoff reduction the psychological and awareness factor is invaluable for society. It is important that green roofs are not viewed as a singular solution, but rather as part of a greater solution in combination with other rainproof measures. I call for more research, experiments and scientific literature that concretely quantifies green roof benefits to support the business case and make it one that is compelling and highly convincing. Further research could expand the scope and investigate successful implementation and critical success factors of green infrastructure in other cities in order to advise on policy instruments that would be of use to the city of Amsterdam. Expansion of green infrastructures in Amsterdam is a slow process that may take as long as the generational change or until policy is effectively implemented. Amsterdam is a leading city on many fronts and until policy is implemented, the city lacks this crucial step that is needed in order to see real, mandated and widespread green infrastructure implementation.

Masters Thesis: Green Infrastructure in Amsterdam Concluding Remarks 9-1

9. Recommendations

9.1 Political Support and Policy Implementation can be greatly enhanced through strong political support and well-constructed policy. Amsterdam is behind in terms of concrete policy that regulates homeowners or developers to implement a type of green infrastructure in new or existing buildings. Policy remains a critical component to this implementation process even though politicians are often hesitant to push policy, as it does not further their political agenda. Policy has the ability to catalyse the wide spread change and transformation as was seen in Hamburg, Germany. Amsterdam should begin with policy that mandates that a green roof or green wall be installed in all new developments. Momentum from example, innovative pilot projects can be gained and can encourage further implementation. This regulation will initiate expansion of existing infrastructure networks. In this case, strong decisions are needed so that the Netherlands does not fall behind by its European counterparts.

9.2 Long-term School Programmes The results of this research have clearly indicated that in order for wide spread and large scale green infrastructure to be implemented a significant ideological shift in government and citizen perspectives needs to take place. This ideological shift from green infrastructure as purely a business case, to one of a highly valuable project is a slow process that can ultimately take at least two generations (Vergoesen, 2016). In order to encourage, promote and ensure that this shift has a strong foundation, government and cities should focus their attention on the younger generation. This is where promotion can have the greatest impact and largest effect. Cities should create long-term programmes that are promoted in schools where children are taught the value of green infrastructure in the city and where they can gain practical experience through tactile green infrastructure projects at their school. Schools with green roofs and green walls that children have an active role in maintaining can be an inspiring tool. Creative examples illustrate the range of possibilities and inspire the children who will usually tell their parents and try to persuade them to participate too. It is hoped that from educating green infrastructure principles and values in schools that it may become embedded in the youth and develop into a standardized practice.

9.3 Deregulation It is important for the city of Amsterdam to deregulate the green infrastructure regulations, as the complex nature and unnecessary rules are often a deterrent to potential green roof installation. Regulations regarding required distances from neighbours and the required distance from the façade can leave a very small area to implement the green roof. This often

Masters Thesis: Green Infrastructure in Amsterdam Recommendations 9-2 causes homeowners to choose the option of wooden decking, as the space isn’t large enough for both green sedum and recreational wooden decking. These regulations need to be revised in order to streamline the process and remove unnecessary complications.

9.4 Comprehensive Approach A comprehensive approach to green infrastructure solution combinations in Amsterdam is needed. All the current focus has been placed on the rainproof aspect which is not the sole benefit to be achieved. A more holistic approach could help improve the marketing and business case to consumers and companies. It is important to consider green infrastructure in combination with other tools, such as rain barrels, where a greater effect could be achieved. This holistic and comprehensive approach needs to be mainstreamed into policy and government.

9.5 More Research Green Roof research is still relatively new and lacking in terms of concrete, quantitative, conclusive research on the range of benefits. More research is still needed to provide evidence to convince the public and the companies of the positive business case.

Masters Thesis: Green Infrastructure in Amsterdam Recommendations R-1

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Masters Thesis: Green Infrastructure in Amsterdam References A-1

Appendix A | Semi-Structured Interviews

Expert Interviews 1. Spaan, K. (2016). Interview with C.Vosloo on 1 April. Amsterdam. 2. Boxem, T. (2016). Interview with C.Vosloo on 4 April. Amsterdam. 3. Hartog, P. (2016). Interview with C.Vosloo on 7 April. Amsterdam. 4. Uittenbroek, C. (2016). Interview with C.Vosloo on 20 April. Amsterdam. 5. De Laat, M. (2016). Interview with C.Vosloo on 22 April. Amsterdam. 6. Klapwijk, F. (2016). Interview with C.Vosloo on 25 April. Amsterdam. 7. Stuurman, R. (2016). Interview with C.Vosloo on 3 May. Amsterdam. 8. Van de Ven, F. (2016). Interview with C.Vosloo on 4 May. Amsterdam. 9. Vergoesen, T. (2016). Interview with C.Vosloo on 4 May. Amsterdam.

Citizen Interviews 10 Fontijn, L. (2016). Interview with C.Vosloo on 11 April. Amsterdam. 11 Tjoe Nij, H. (2016). Interview with C.Vosloo on 14 April. Amsterdam. 12 Swagerman, E. (2016). Interview with C.Vosloo on 15 April. Amsterdam 13 Dragoudaki, G. (2016). Interview with C.Vosloo on 3 May. Amsterdam. 14 Medea Csapo, V. (2016). Interview with C.Vosloo on 3 May. Amsterdam. 15 De Ritis, F. (2016). Interview with C.Vosloo on 13 May. Amsterdam. 16 Oosterhout, R. (2016). Interview with C.Vosloo on 13 May. Amsterdam.

Expert Interview Example Questions:  Where are you from? What did you study? Where?  Did you attend graduate school?  How did your career start? Where did you start?  What position are you in now?  What do your main tasks include?  How involved are you in the green infrastructures in Amsterdam?  What tasks are you involved in? Or tasks you coordinate?  Can you tell me more about the tasks you are currently busy with?  What are the main goals for the green infrastructure in the inner city of Amsterdam?  What is your opinion of the progression? How close are you to achieving these goals?  How much do you think it could contribute to the reduction of surface water runoff?  What are the main promoted and perceived benefits?  What potential do you see for green infrastructure in Amsterdam?  What do you see as the main challenges to the implementation of green infrastructure?  Have you encountered any problems with the implementation?  What does the city see as problems/challenges/road blocks?  What do you think could still be done to help achieve these goals? Solutions to the challenges?

Masters Thesis: Green Infrastructure in Amsterdam Appendix A | Semi-Structured Interviews A-2

 Why do you think that not more people are getting involved?  What do you hope for? What do you hope the next ten years will look like if you can make a hopeful prediction?  How does government hope to get more green roofs implemented without financial incentives?

Masters Thesis: Green Infrastructure in Amsterdam Appendix A | Semi-Structured Interviews B-1

Appendix B | Q-Methodology

Appendix B-1: Set of 21 Q-Methodology Statements

(1) Government does not (2) Green roof maintenance (3) Owning a green roof creates (4) The green roof subsidy (5) People are disengaged and offer enough incentives for is deemed too costly and complexities among the building does not appear to be disinterested in getting involved green roof implementation this acts as a deterrent for occupants in terms of the benefit effective. and having their own green roof. to developers. developers and building to each owner and utilities owners. arrangements.

(6) Roof rights and roof (7) The public seem (8) The age of the inner city (9) The incentives and (10) The physical construction usage may put ground floor unaware regarding the green historic buildings create issues benefits offered by the of some roofs means they often residents off from roof subsidy. for green roof implementation. municipality are not cannot hold the load of a green contributing towards a persuasive enough for roof. building feature that doesn’t developers. benefit them. (11) Citizens seem unaware (12) Green roofs create (13) Citizens do not feel (14) Home owners are mostly (15) Home owners and self- as to the endless more issues regarding implementing their own green concerned with their home builders are deterred by the possibilities of green roofs maintenance, management roof offers enough benefits. construction and not with increased design and and green infrastructures. and cost. complex extras that could construction cost. delay their construction. (16) Issues with strong (17) Government needs to (18) In multiple resident (19) Citizens are unaware that (20) Citizens are interested and winds make the feasibility focus more on promotional buildings agreement among extensive green roofs need willing to give green roofs a try of green roofs difficult in advertisement campaigns residents regarding green roofs little maintenance and have a but are unsure how to go about it some areas. and creating awareness is very difficult to achieve. much lighter structural load. and implement the structure. among citizens. (21) Structural loading issues in some historic buildings make it too costly to first create a solid structure and then implement a green roof.

Masters Thesis: Green Infrastructure in Amsterdam Appendix B | Q-Methodology B-2

Appendix B-2: Q-Distribution used in the Q-Methodology for this study

Masters Thesis: Green Infrastructure in Amsterdam Appendix B | Q-Methodology C-1

Appendix C | Table of Calculations

Appendix C-1: Approximate calculations of the current permeable green areas present in Amsterdam (km2)

Type of Green Present in Amsterdam Total Area Area Parks Westerpark Sarphatipark Erasmuspark Meerpark Wachterliedplantsoen Park Frankendael Frederik Hendrik Plantsoen Wibautpark Overtoom se Veld Oosterpark 2,96km2 Vondelpark Flevopark Park Schinkeleilanden Funenpark Beatrixpark Rietlandpark Martin Luther King Park Huis te Vraag Park Somerlust Botanical Hortus Botanicus Amsterdam Gardens & Arboretum De Nieuwe Ooster Plantations 3,41km2 Wachterliedplansoen Frederik Hendrik Plantsoen Zoos Natura Artis Magistra 0,15km2 Sport Parks Sportpark Olympiaplein Sportpark Drieburg 0,12km2 Sportvereniging De Meer Sportparken Amsterdam Oost Cemeteries Rooms-Katholieke Begraafplaats Begraafplaats Zorgvlied 0,25km2 Begraafplaats Vredenhof PC Hooft Sedumdaken Fietsenstalling Kantoor Prinsengracht Oudeschans ING Prinsengracht Korte Koningstraat Barentzplein Weteringschans Korte Koningstraat Bickersgracht Nicolaas Amstel 1 Nieuwe Houttuinen Witsenkade Nieuwe Doelenstraat De Wittenstraat Nicolaas Oudezijds Achterburgwal Witsenkade Marnixstraat Kalverstraat 0,03 km2 Prinsengracht Noordermarkt Spui Amstel Herenmarkt Nieuwezijds Wachterliedplantsoen Nieuwe Voorburgwahl Prinsengracht James Cookstraat Singel GGD Egelantiersgracht Jacob van Lennepkade Entrepodok Keizergracht 621 Plantage

Masters Thesis: Green Infrastructure in Amsterdam Appendix C | Table of Calculations C-2

Heregracht Middenlaan Tweede Helmerstraat Oosterdokskade Niuewe Derde Kostverlorenkade Dijksgracht Herengracht Overtoom Bloemgracht A.S Werf Kattenlaan Onderwijzenhof Eerste Rozendwarsstraat Roemer Visscherstraat Nieuwe Keizergracht Surinameplein Uilenburgerstra Prinsengracht at Overtoom Leidestraat Korte Zocherstraat Kerkstraat Keizerdwarsstr Zocherstraat Jacob Obrechtstraat 3 aat Frans van Mierrisstraat Jacob Marisstraat Saxen Frans van Mierrisstraat Weimerlaan Jacob Marisplein Pieter de Hoochstraat Valeriusstraat Bennebroekstraat Wouwermanstraat Cornelis Bennebroekstraat Pieter de Hoochstraat Krusemansstra Sloterkade at Roelofhartstraat Sloterkade Des Presstraat Jan van Eijckstraat Rijnsburgstraat Johanes Gerrit van der Veenstraat Ijsbaanpad Verhulstraat Stadionweg Baarsstraat De Beatrixpark Heidenstraat Lairessestraat Prinses Marijkestraat Sarphatipark Jacob Eerste van Campenstraat Obrechtstraat Van Ostadestraat Eerste Jan van der Palestrinastraa Ruysdaelkade 215 t Laing's Nekstraat Kuiperstraat Jan Willem Woltera van Reestraat Rustenburgerdwarsstraat Brouwerstraat Eerste Atjehstraat Pieter Aertsstraat De Soembawastraat Diamantstraat Lairessestraat Soembawastraat Karel du Jardinstraat Nicolaas Semarangstraat Ijselstraat Maesstraat WTCW 408 Dintelstraat Nicolaas Kea Boumanstraat Maesstraat Roerstraat Kea Boumanstraat Amsteldijk Victorieplein 11 Scheepstimmermanstraat RAI Hoendiepstraat Stuurmankade President President Kennedylaan Kennedylaan Stade de Colombes Middenweg Gaasterlandstr Stade de Colombes Middenweg aat 5 Linnaesparkweg Middenweg Hogeschool van Middenweg Wakkerstraat Amsterdam Middenweg Wakkerstraat Overamstelstra Hogenweg Linnaesparkweg at Hogenweg Weesperzijde Hogenweg Fahrenheitstraa Borneokade t Panamakade

Seiwachterstraat/Erstkade Stuurmankade

Masters Thesis: Green Infrastructure in Amsterdam Appendix C | Table of Calculations C-3

Green Walls Sportplaza Mercator Carolina MacGillavrylaan 0,002 Borneokade 141 km2 Van Diemenstraat Kruidendaken Da Costakade 0,001 Prinsengracht km2 NEMO Grasdaken Wibautstraat 0,0002 km2 Daktuinen Hudsonhof Tweede van der Helststraat Eerste van der Helststraat 14-36 Spaklerweg 0,013 Van Woustraat km2 Kattenburg Hoogte Kadijk Retiefstraat Soembawastraat boven school Solar- Vredenhofpad Linnaesparkweg Sedumdaken Magalhaensplein Newtonstraat Sloterkade Kea Boumanstraat Stade de Colombes Omval 0,001 Anfieldroad Wesperzijde km2 Fahrenheitstraat Blankenstraat Middenweg 119 Stichtstraat Banstraat Van Ostadestraat Combined Total Green Area 6,98 km2 Amsterdam Study Area 46,87 km2 Green Area as a Percentage of Study Area 14,9%

Masters Thesis: Green Infrastructure in Amsterdam Appendix C | Table of Calculations D-1

Appendix D | Images

Appendix D-1: Images illustrating the flooding effects after the 28th of July 2014 cloud burst in Amsterdam (Source: www.nltimes.nl).

Appendix D-2: Images of the green infrastructure Sports Park Mercator building in Amsterdam (Source: Christi Vosloo)

Masters Thesis: Green Infrastructure in Amsterdam Appendix D | Images D-2

Figure D-3: Satellite image indicating the total volume of rainfall (mm) received by each area of Amsterdam during the 28 July cloud burst of 2014 (Source: www.rainproof.nl)

Masters Thesis: Green Infrastructure in Amsterdam Appendix D | Images D-3

Appendix D-4: An example of an informational brochure distributed by Amsterdam Rainproof to illustrate examples of rainproof measures citizens can implement (Source: www.rainproof.nl)

Masters Thesis: Green Infrastructure in Amsterdam Appendix D | Images