IACSC 2023: Book of Abstracts

About IACSC

The International Academic Consortium for Sustainable Cities (IACSC) was established in September 2009 with an initiative of the Yokohama City University (YCU). It was originated from a meeting session entitled “Cities and Universities – Towards Collaboration for Sustainable Cities” during the conference of CITYNET, Yokohama on September 9, 2009, in which YCU served as a coordinator.

The IACSC aims to develop cooperation, to foster dialogues and discussions, to encourage sharing of information and resources and to promote research and collaborative activities among academic and research institutions as well as to strengthen relationship among universities and cities to contribute to a sustainable society.

The six universities forming the IACSC network include: Yokohama City University (Japan),Thammasat University (Thailand), Vietnam National University

- Ho Chi Minh City (Vietnam), Hasanuddin University (Indonesia), University of the Philippines (Philippines), and Universiti Sains Malaysia (Malaysia).

Welcome message

“ Welcome to the 14th International Academic Consortium for Sustainable Cities 2023 (IACSC 2023) under the theme “Peri Urbanization- From Bangkok Metropolitan to Region” at Thammasat University Rangsit Center.

Thammasat University is ready to become a “World Class University for the People” with the 4 main strategic groups: Future Workforce, Future Workplace, Future Life and Society and Future Collaboration; to transform Thammasat University to be more than just an institutional space, striving to progress toward being a space for innovation in all dimensions and creating a new generation leaders for the future.”

Associate Professor Gasinee Witoonchart, Rector of Thammasat University

Mario A. Cudiamat, Maria Grechelle D. Perez, Ruby D. Olipany, Cynthia B. Mintu

Lihoun Teang, Chansopheaktra Sovann and Kim N. Irvine

Parallel Session 1 –

Public Health and Environment

Development of Japanese and Indonesian versions of the e-Health Literacy Scale

Yayoi Shoji1*, Andi Masyitha Irwan2, Ryota Ochiai1, Syahrul Syahrul2, Eriko Shinohara1, Andi Muhammad Fiqri2, Shoko Takeuchi1, Erfina Erfina2, Mariko Iida1, Ariyanti Saleh2, Fusae Moriguchi1, Sachiyo Nakamura1, Yuka Kanoya1

1 Yokohama City University

2 Hasanuddin University

*Correspondence: shoji.yay.du@yokohama-cu.ac.jp

Introduction:

Reportedly, e-health literacy is lower in younger people than in those in their 40s and 50s, despite the internet being an essential information source for youth. We developed Japanese and Indonesian versions of the e-Health Literacy Scale (e-HLS).

Methods:

Conceptual equivalence was verified using the forward–backward translation method. First- to fourth-year nursing students at two universities in Japan and Indonesia were surveyed using a web-based questionnaire, including a 12-item e-HLS. After item analysis, confirmatory factor analysis and hypothesis testing confirmed whether e-health literacy increases as grades increase. Cross-cultural validity/measurement invariance was evaluated via multiple-group confirmatory factor analysis. Both ethics review boards approved this study.

Results:

Ninety-nine Japanese and 407 Indonesian participants responded to the survey. Neither country showed item distribution skewness, and no ceiling or floor effects were detected. Confirmatory factor analysis supported the same three-factor structure as the original e-HLS. Hypothesis testing indicated that the 4th grade had higher overall, functional, and interactive health literacy scores than grades 1-3. There were no significant differences between the two groups in terms of critical health literacy (1st-3rd grade, mean=3.85: 4th grade, mean=3.96: p=0.051). Cronbach’s alpha coefficients were 0.86 overall and 0.74–0.83 for each of the three domains. Constructive invariance and full metric invariance models showed a good fit, but scalar invariance was not supported.

Conclusion:

The content validity (relevance, comprehensiveness, and comprehensibility), construct validity (structural, cross-cultural, convergent, and discriminant validity), and reliability (internal consistency) of the Japanese and Indonesian versions of the eHLS were confirmed.

Towards an Asian Regional Framework for Wastewater-based Epidemiology

Tomoko Takeda1, Masaaki Kitajima2, Eiji Haramoto3

1 The University of Tokyo

2 Hokkaido University

3 University of Yamanashi

The impact of the COVID-19 pandemic has been widely felt across Asia. In the regional effort to develop solutions to combat the pandemic, wastewater-based epidemiology has gradually gained recognition as an effective tool to monitor the prevalence of the pandemic in communities. When accurately and regularly monitored, wastewater samples from a community emitting the wastewater can represent the status of health without needing to monitor each and every individual in the community. In this paper, we will introduce recent scientific and technological advancements including highly sensitive and rapid virus detection methods based on the quantitative polymerase chain reaction (qPCR), as well as findings from analyzing wastewater and environmental water for the SARS-CoV-2 RNA as an indicator of the communitylevel COVID-19 prevalence across the Asian region. We will discuss and propose a potential framework for wastewater-based epidemiology at the regional level to support the decision-making process in preparation for future pandemics. It is hoped that such frameworks will be able to prevent the loss of lives and decrease the potential impact from future pandemics in Asia.

E. coli Levels Associated with Source Waters and Household Handling Practices of Potable Water in Peri-urban Phnom Penh, Cambodia

Kim N. Irvine1, Thomas P. Murphy2, Lihoun Teang1, L.M. Lok3, S. Kok4, E. Chea4, and S. Sovann4

1 Thammasat University, Thailand

2 International University, Cambodia

3 Nanyang Technological University, Singapore

4 Royal University of Phnom Penh, Cambodia

Cambodia has made progress towards addressing Sustainable Development Goal 6.1. “By 2030, achieve universal and equitable access to safe and affordable drinking water for all”, but challenges remain in fully realizing this target. We begin this presentation by reviewing current country-wide access to safe and affordable water as an update to a paper we published on this issue more than 15 years ago. Subsequently, we report on the results of water sampling done for E. coli in a peri-urban area north of Phnom Penh that was conducted between 2018 and 2020. The sampling examined E. coli levels in source waters, including rivers, ponds, a large lake/wetland, wells, rainwater harvesting systems, piped water, and bottled water. Sampling from household storage containers and in-home drinking cups also was done to assess the effects that handling practices might have on exposure to E. coli. We show that country-wide, as well as in the peri-urban study area, there has been increased access to piped water. Piped water and commerciallyavailable bottled water (0.5-1.5 L PET bottles) had the lowest E. coli levels in our study area, although such bottled water is not an affordable alternative for many peri-urban families. Surface pond water and the Tonle Sap River contained the highest E. coli levels and would pose the greatest risk associated with direct consumption. Handling practices may impact drinking water quality, as a significant difference (p=0.2) was found in E. coli levels between samples taken from commercially-available 0.5-1.5 L PET bottles and from household cups into which the bottled water was poured. There also was a significant difference (p <0.05) in E. coli levels between piped water sampled directly from the tap and piped water stored in bulk household containers. The geometric mean concentration of E. coli in large, covered, traditional outdoor storage jars used for rainwater harvesting was nearly 10 times lower than the same type of jars that were not covered. Despite the increasing availability of piped water service in the study area, we found a diversity of water source practices, including use of rainwater harvesting, surface water, 20 L bottled water, and wells. Wastewater discharges from Phnom Penh were effectively treated by a large, natural wetland, Boeng Kob Srov. However, there was considerable spatial variability in E. coli levels for this surface water system, with lower levels moving away from the wastewater discharge points, into the wetland, but recontamination from local sources occurring along the discharge canal to the Tonle Sap River. This type of surface water system connectivity needs to be considered in managing down-stream water intakes. The study illustrates the advantages of field-based testing for effective screening of E. coli in peri-urban areas.

Microbiological Assessment of Indoor Air in Outpatient Department in a University Hospital

Thanchira Saita1, Kanchaporn Chaipat1, Sasrinakarn Weerated1, Nontiya Homkham1, Saowanee Norkaew1 and Pirom Noisumdaeng1,2*

1 Faculty of Public Health, Thammasat University

2 Thammasat University Research Unit in Modern Microbiology and Public Health Genomics

*Corresponding author: pirom.n@fph.tu.ac.th

The indoor environments in a hospital are influential factors for affecting human health. The main reason is the poor indoor air quality affected by the presence of microorganisms leading to hospital-acquired infections through air-borne transmission. The objectives of the study are to evaluate the concentration and species of bacteria, and the presence of influenza A viruses in the indoor air sampled from the outpatient department in the university hospital, Pathum Thani. Indoor air was collected for 3 hours at a flow rate of 1 liter/minute using the Impingement method at randomly selected six points of the patient care service area. Three indoor air parameters including temperature, humidity and CO2 concentration were measured. The bacterial colonies were assessed by standard plate count method. The 16S rRNA gene sequencing for species identification and drug susceptibility test were performed. The influenza A viruses were detected using RT-PCR and gel electrophoresis. Our microbiological analyses revealed that the bacterial concentration ranged from 55-722 CFU/m3. 16S rRNA gene sequencing and phylogenetic analyses identified bacterial species including Staphylococcus saprophyticus, S. nepalensis, S. cohnii, S. arlettae, S. epidermidis, Bacillus velezensis, and Sphingomonas sp. Those isolates, except S. saprophyticus, are susceptible for four kinds of drugs tested. No influenza A viruses were detected. The indoor air quality of some study points is unacceptable compared to the Thai Indoor Air Quality standards. Therefore, the control of those environmental factors in a hospital is necessary for safety and to reduce the risk of infection by opportunistic pathogens in susceptible persons.

Socio-Ecological System of the Silang-Santa Rosa Sub-watershed in the Context of Urban, Climate, and Disaster Resiliency

Kaymart Gimutao1, Mark Dondi Arboleda1, Decibel Faustino-Eslava1, Damasa Macandog2, Patricia Sanchez1

1 School of Environmental Sciences and Management, University of the Philippines Los Baños 2 Institute of Biological Sciences, University of the Philippines Los Baños

The cities of Binan, Cabuyao, and Santa Rosa and the Municipality of Silang are expanding urbanized areas due to their proximity to Metro Manila. The four areas are situated in the same subwatershed known as the Silang-Santa Rosa Subwatershed. Because of rapid urbanization and dramatic land use change in the subwatershed, its integrity was compromised and its natural capacity to retain water was reduced. This study explored the bio-physical and anthropogenic factors that impacted the land use modification in Silang-Santa Rosa Subwatershed and identified the population group that will most likely be exposed to pressing climate change-related hazard in the area. The comparison of the old topographic maps and the current maps of the subwatershed revealed a massive land use conversion in the area which obliterated some of the important waterways of the river system in the lowland as well as the recharge areas in the upland. This study also identified possible exposure of the subwatershed’s population to flood and other hazards using the online government tool Geoanalytics. All 10 barangays1 with largest population exposed to flood are low-lying and in proximity with the Laguna de Bay. Using Pearson’s correlation, this paper identified hazards that could be related to flood such as liquefaction, rain-induced landslide, and earthquake-induced landslide (by comparing the number of vulnerable populations per hazard) to optimize possible adaptation measures. Liquefaction has strong correlation with flood both in terms of total population at risk (r = 0.575, 95%, p = 0.001) and the population that are highly at risk (r = 0.705, 95%, p = 0.001). Cooperation and partnership among local governments to collectively address emerging hazards in the sub-watershed led to the institutionalization of the Silang-Santa Rosa Watershed Management Council.

1 Smallest administrative unit in the Philippines which is under the jurisdiction of a city or municipality

Visioning Landscape: Redesigning Eco-Industrial Park at Amata City

Achitpol Sripodok1, Jinjutha Gymsookh1, Natchanon Serirak1, Fa Likitswat1, and Siwaporn Klinmalai1

1Faculty of Architecture and Planning, Thammasat University, Pathum Thani, Thailand

Through the promotion of the Eastern Economic Corridor of Thailand, Amata City has become one of the largest industrial estates in the country, covering a vast area of 43 square kilometres or 4,330 hectares in the provinces of Chonburi and Chachoengsao. Despite its growth, the challenge of preserving local ecosystems and livelihoods for the surrounding neighbourhoods remains. To address these issues, the sustainable landscape design studio at the Faculty of Architecture and Planning at Thammasat University has conducted a study to analyse and redesign the ecological connection between Amata City and its surroundings. This presentation focuses on two scales of design proposals: a macro-scale landscape vision plan and a micro-scale site planning landscape design aimed at redesigning the eco-industrial park. At the macro-scale, six ecological visioning landscape design proposals were developed. These include: eco-industrial towns, eco-factory and manufacturing, eco-revitalization of local canals, revitalization of water networks, green linkages, and eco-mobility. At the micro-scale, 24 alternative approaches were explored to redesign one of the private manufacturing sites in line with the Smart Environment concept. From a total of 24 alternative designs, three selected proposals were selected as part of a further development idea and guideline plan. The site planning showcases strategies for developing a circular water management plan, wastewater treatment and control, sustainable energy management, promotion of local habitat and biodiversity, and connecting with local communities. We recommend further multidisciplinary studies involving environmental engineering, urban hydrology, and feasibility analysis to ensure the effective implementation of these design proposals.

Modeling and Performance Assessments of Water Management Design Options for an Industrial Estate, Amata City, Thailand

Chanya Kloysuwan1, Hein Lin Thant1, Salai Ye Yint Aung1, Chen Liuyi1, Attanayake Mudiyanselage Indrajith Udaya Kumara1, Thammarat Koottatep1, and Kim N. Irvine2

1 Environmental Engineering and Management, Asian Institute of Technology, Thailand

2 Faculty of Architecture and Planning, Thammasat University, Thailand

Nature-based Solution design approaches to manage urban runoff and enhance environmental quality are gaining traction globally. However, it is important to optimize both the form and function of the design and this requires a multidisciplinary approach. Our study undertook a modeling effort to optimize two different designs for an eco-industrial park in Amata City that were provided by a landscape architecture team.

PCSWMM (Personal Computer version of the Stormwater Management Model) was used to model the runoff, hydraulics, and water quality for the scenarios using a 50 mm, 24 hour SCS Type II design storm having a return period of 1.3 years. Model results showed that a combination of constructed wetlands and permeable pavement could eliminate flooding for the design storm, as compared to current conditions, as well as improve runoff quality.

Parallel Session 2 –

Urban and Regional Planning Issues

Systems Thinking: A Pathway towards Regenerative Peri-urbanization

Koen De Wandeler1 and Luc Eeckhout1

1 KU Leuven Faculty of Architecture, BELGIUM

The COVID-19 pandemic demonstrated that encroaching on the natural habitat of animal species – as exemplified in peri-urbanization – enhances the risk of wide-spread zoonoses. It evidenced that global challenges like pandemics and climate change readily become interlinked with economic, societal and spatial issues and ramify into compound urban crises that cannot be solved in isolation but must be examined using systemic and interdisciplinary competences. This approach involves strengthening economic, social, and environmental resilience in urban systems, whereby ‘systems’ are understood as sets of interconnected elements that generate their own patterns of behaviour and serve a purpose.

This paper first relates urban crises to the global challenges of overshoot and collapse, demonstrating that our attitude towards the earth and our relationship with it are now not only outmoded but dangerous. It then adopts systems thinking to unravel these amalgamated crises, notably those related to suburbanization. Systems thinking has been instrumental in promoting circularity by mapping production and consumption cycles and ensuring that they create a closed-loop system. Its contribution to regenerative thinking was to instill a full and comprehensive understanding of natural and living systems into design practices that focus not only on reducing environmental impact and conserving natural resources but also on learning how to engage nature as a ‘co-equal’ partner. Our presentation illustrates these principles by examining the architectural studio design process and design visualizations. We conclude by showing how regenerative design can guide environmentally sound retrofitting of built-up urban areas as well as ecologically balanced urbanization of peripheral areas.

References

De Wandeler, K., & Lo, A. (2022). International Multidisciplinary Summer School: Systemic Design for Health

- Infectious Diseases Prevention and Control (T. Gerdpratoom & Z. Wint Nwe, Eds.). Thammasat Design School. https://issuu.com/tds.thammasat/docs/summer_school_2022_booklet_220925

Meadows, D. H. (2008). Thinking in systems: a primer (D. Wright, Ed.). Chelsea Green Publishing.

Srinivas, Hari, “Moving towards a Circular Economy: More than Just 3Rs!”. GDRC Research OutputConcept Note Series E-097. Kobe, Japan: Global Development Research Center. Retrieved from https://www.gdrc.org/uem/waste/more-3r.html on Thursday, 3 August 2023

Westman, L., Patterson, J., Macrorie, R., Orr, C. J., Ashcraft, C. M., CastánBroto, V., Dolan, D., Gupta, M. van der Heijden, J., Hickmann, T. Hobbins, R., Papin, M., Robin, E. Rosan, C. Torrens, J., and Webb, R. (2022). “Compound urban crises”. Ambio, 51(6), 1402-1415. WHO (2023), https://www.who.int/news-room/fact-sheets/detail/zoonoses

A Study on the Characteristics of Townhouses in Japan’s Heavy Snowfall Areas

Marina Kitahara1

1 Assistant Professor, Global Cooperation Institute for Sustainable Cities (GCI), Yokohama City University (YCU)

In Japan, historical central commercial districts in snowy regions have traditional arcades that ensure safe walking and allow customers to enter and exit stores even during snowfall. These are called “komise” or “gangi”. Underneath these arcades is generally private property, not a public street, and each townhouse offers it free of charge for the convenience of pedestrians. The use of back lots in townhouses is also distinctive, but this has not been clarified in previous studies. This study uses the historical central commercial district of Kuroishi City as a case study to clarify the characteristics of the back lots in detail. In Kuroishi City, the townhouse is characterized by having “komise” on the front and “kaguji” on the back. “Kaguji” is a dialect word and is used to refer to the back lots. This study mainly focuses on “kaguji” and aims to identify its characteristics of use and ownership by interviews with landowners and analysis of the registry.

Smart City Development Policy - Comparing the Case in Ho Chi Minh City, Vietnam and Busan, South Korea

Khanh Lan Thi Ta1, Tuyen Thanh Vo2, and Thanh Phuong Thi Tran3

1 Faculty of Political Science, HCMC Institute for Cadre Development, Vietnam

2 Master, Faculty of Urban Studies, University of Social Sciences and Humanities, VNU-HCM

3 Bachelor, Urban Management Department Thu Duc City, TP. Ho Chi Minh City

The pursuit of smart city development, consistent with the industrial revolution 4.0, is a global phenomenon, including in Vietnam, and potentially brings out many benefits and advantages. In 2016, the office of the government of Vietnam issued Official Letter No. 10384/VPCP-KGVX, to address the building of sustainable smart cities in the world and Vietnam. Subsequently, many activities to deploy the construction of smart city development projects occurred throughout Vietnam, and most notably in Ho Chi Minh City (HCMC). In this context, many major cities around the world have implemented policies and strategies to build smart cities. Within the scope of this article, we focus on analyzing Busan’s smart city development policy and compare it with HCMC’s current smart city development policy. The article also discusses the effectiveness of implementing these policies in the two cities, as well as reviewing difficulties in implementing policies. Based on our study findings we provide some recommendations for cities to build and effectively manage smart cities.

Sustainable Development Practices in the Component Cities of Batangas, Philippines: A Framework to Responsible Growth and Resilient Urban Economy

Mario A. Cudiamat1*, Maria Grechelle D. Perez2, Ruby D. Olipany1, Cynthia B. Mintu1

1 Institute of Arts and Sciences, Far Eastern University-Manila, Philippines

2 College of Arts and Sciences, University of the Philippines Los Baños, Philippines

*corresponding author: macudiamat@feu.edu.ph

This study aims to describe the development practices of five component cities in the province of Batangas, namely Calaca, Batangas City, Sto. Tomas, Lipa, and Tanauan, using the sustainable development framework. The research employed a descriptive-qualitative research design focusing on the perspectives of sustainable development encompassing socio-cultural, economic, and ecological sustainability. Secondary data from the Socio-Economic and Physical Profile (SEPP) and Comprehensive Land Use Plan (CLUP) of Batangas were utilized to identify sociocultural and ecological profiles. Additionally, the Department of Trade and Industry’s (DTI) Competitive Indices are employed to describe the economic dimension of sustainability, incorporating factors such as economic dynamism, government efficiency, infrastructure, efficiency, and innovation. The results of the study indicate that the component cities of Batangas are making significant strides toward sustainability. Socio-cultural, economic, and ecological aspects of sustainable development have been addressed, showcasing their commitment to balanced growth and development. However, challenges still exist in attaining full ecological sustainability, and there are areas of concern in the economic dimension. Based on the findings, it is recommended to develop a localized Environmental Performance Index (EPI) for municipalities and cities in the province, focusing on crucial factors like climate change, ecosystem vitality, and environmental health. Such an index could serve as a comprehensive tool to measure and monitor progress toward sustainability goals, facilitating better decision-making and planning for future development. In conclusion, the component cities of Batangas are making commendable efforts toward sustainable development. However, continued dedication and targeted interventions are necessary to address remaining challenges and ensure a more robust and enduring path towards holistic sustainability in the region.

Future Sprawl: Sustainable Development of Productive Urban-rural Fringe Community

Landscape Design and Planning in Wuhan, China

Sunantana Nuanla-or1

1 Department of Landscape Architecture, Birmingham Institute of Fashion and Creative Arts (BIFCA), Wuhan Textile University, China

“Wuhan, Different Every Day!” this slogan reflects the dynamic of Wuhan, the largest developing city in central China. Wuhan continuously strives for development; however, in recent years the effects of rapid urbanization have brought complex problems such as over population, unplanned urban sprawl leading to the degradation of the green and blue natural environments, and farmlands gradually disappearing. Furthermore, during the 2020 lockdown, urban food shortages became one of the most important challenges for the city. Many urban dwellers faced the difficulty of food accessibility, especially for fresh products. As the wave of urbanization reshapes the city’s productive fabric, the important question needs to be addressed: How can the scales of urban growth be harmonized with the imperative of preserving local productive landscape and natural environments?

The study examines the present situation and impact of Wuhan’s urban sprawl and the articulation of China’s Sponge City program in landscape architecture and planning of urban-rural fringe communities. The study found that the sprawl caused degradation of blue and green infrastructures and loss of productive landscapes in favor of the emerging Monocultural residential communities. These peri-urban developments generally lack Sponge City initiatives. I present a comparative case study of successful built projects that integrated productive landscape and communities. I also review strategies and design guidelines in landscape design and planning that integrate considerations of development and the environment. From the combination of the two research methods, the study demonstrates design solutions that apply theoretical insights into landscape design and planning, proposing a new innovative alternative to Wuhan’s future sprawl.

Urban Observation Behaviors and Design Guidelines for Green Spaces in Doun Penh District

Chea Lisovannara1

1 Faculty of Architecture and Planning, Urban Design & Development International Program (UDDI), Thammasat University, Thailand

Urban green spaces are a component that help to improve people’s quality of life in densely populated cities. However, the urban green spaces in older districts of Phnom Penh, such as Daun Penh, at the city’s heart do not offer equal opportunities to everybody, and landscape design elements do not meet the needs of everyone in terms both of quality and quantity. This research proposes a redesign, and recommendations for existing green spaces, and identifies priority areas for developing more green spaces to improve the quality and quantity of green space in Doun Penh district.

Tragedy of the (Mismanaged) Commons: The Disappearing Natural Wetlands of Phnom Penh

Lihoun Teang1, Chansopheaktra Sovann2,3 and Kim N. Irvine1

1 Faculty of Architecture and Planning, Thammasat University, Rangsit Center, Thailand

2 Department of Environmental Science, Royal University of Phnom Penh, Phnom Penh, Cambodia

3 Department of Physical Geography and Ecosystem Science, Lund University, Sweden

A central theme of Garrett Hardin’s seminal 1968 paper considered the pressure that greater population places on the “commons” or land held for public benefit. He later modified his discussion to include the idea that a “managed commons” was essential, where the management philosophy could follow either a socialism or privatism of free enterprise approach, concluding Either one may work; either one may fail… but with no management disaster is certain. There has been considerable discussion and disagreement regarding Hardin’s ideas, but we argue here that the recent evolution of the waterscape in Phnom Penh, Cambodia, is well-described as a Tragedy of Mismanaged Commons. Phnom Penh has experienced remarkable change over the past 60 years. Known as the “Pearl of Asia” from the 1920’s to the early 1970’s, it was evacuated and essentially abandoned during the Khmer Rouge period, 1975-1979. By 2000 the city’s population reached 1.149 million and by 2022 it stood at 2.211 million. This population increase is commensurate with an increase in urban land use classification from 4,000 ha in 1990 to 25,000 ha in 2015. The national GDP per capita (PPP) also increased from $1,937 USD in 2006 to $4,583 USD in 2019 and this greater wealth is reflected by development in Phnom Penh. Natural wetlands historically have been part of Phnom Penh’s waterscape, providing ecosystem services to the community. The objective of this presentation is to review the loss of Phnom Penh’s wetlands that has accelerated dramatically in the past three years and discuss the concurrent loss of ecosystem services. Between 2003 and 2018, approximately 40% of Phnom Penh’s wetland area was lost. More specifically, the 90 ha Boeng Kak was entirely filled in for development between 2009 and 2013. Boeng Cheung Ek and Boeng Kob Srov wetlands both effectively treat the city’s wastewater and provide livelihoods, food provisioning, homes, and other cultural services. The economic value for wastewater treatment, food, and water provisioning in Boeng Cheung Ek was estimated as $30.12 million USD per year and the wetland also provided urban heat island mitigation. Approximately 300 families live on the shores of Boeng Kob Srov, often occupying informal housing and earning a living through fishing, aquaculture, and home-based businesses. Boeng Kob Srov is designated state public property, which should ensure its place as a commons and preclude private development. However, satellite image analysis shows that in 2019 the surface area of Boeng Kob Srov was 48.5 ha less than the original area of 3,240 ha due to infilling, while by 2022 the surface area was 1,070 ha less than the original surface area. The surface area of Boeng Cheung Ek was reduced by approximately 43.9 ha in 2019 compared to the original 1,300 ha area, with the infilling increasing to a total of 185.6 ha in 2022. Drivers of the infilling include a stronger GDP, increased foreign direct investment, rural-urban migration, and fluid land policy and planning, particularly in areas occupied by those with low socioeconomic standing. This infilling and development, resulting in displacement of marginalized communities at the expense of gated communities or boreys, truly represents a tragedy of the mismanaged commons.