12. Clean Water and Sanitation

Sustainable Development Goal 6: Clean Water and Sanitation, focuses on ensuring access to water and sanitation for all.

Professor David Meyer completed his PhD and M.Sc. in Mechanical Engineering at MIT and is an alumnus of Engineering Science (Energy Option) at U of T. Before his graduate studies, David worked for Engineers Without Borders Canada (EWB) in Ghana and for a engineering consulting firm called HydraTek in Toronto. His research focuses on urban water distribution infrastructure, and specifically how this infrastructure behaves in Mega Cities in the Global South. His research group works on projects including new ways of managing and modelling megacity water networks, especially when they turn on and off frequently. These intermittent systems affect one billion people! He also runs the Sensing Health In Toilets Lab (an acronym he is proud of) where they try to measure the health of a community from within its toilets. 

Samantha LeValley is a first-year PhD Student in Civil Engineering in the Centre for Global Engineering at UofT. She completed her MASc in Civil Engineering at UofT in 2021 along with the Collaborative Specialization in Global Health. The goal of her PhD research is to understand how equitable current improved rural water supplies are and how that equity changes with seasonality and compares between two different contexts in the Global South.

CREDITS: This podcast is co-hosted by Dr. Erica Di Ruggiero, Director of the Centre for Global Health, and Ophelia Michaelides, Manager of the Centre for Global Health, at the DLSPH, U of T, and produced by Elizabeth Loftus. Audio editing is by Sylvia Lorico. Music is produced by Julien Fortier and Patrick May. It is made with the support of the School of Cities at U of T. 

Transcript

Erica Di Ruggiero [00:00:07] I'm Eric Di Ruggiero and this is Healthy Cities in the SDG Era, a podcast about the Sustainable Development Goals and how research conducted by faculty and students at the University of Toronto is helping to achieve them. We're recording from Toronto or Tekaronto, which for thousands of years has been the traditional land of the Huron, when the Seneca and the Mississaugas of the Credit. Today, this meeting place is still the home to many indigenous people from across Turtle Island and we are grateful to have the opportunity to work on this land. In this episode we'll look into SDG 6, which focuses on ensuring access to water and sanitation for all. SDG 6 targets include achieving universal and equitable access to safe and affordable drinking water by 2030. Improving water quality by reducing pollution. Protecting water related ecosystems. And strengthening and supporting local community participation in water and sanitation management. Since 2010, the United Nations has proclaimed that access to water, sanitation and hygiene is a human right. Water is essential not only to health, but for poverty reduction, food security, ecosystems and peace and human rights. Yet countries still face growing challenges related to accessing safe drinking water. According to the United Nations, about 2.4 billion people still lack access to basic sanitation services like toilets and latrines. And another 40% of the global population is affected by water scarcity. In this episode, we'll speak with David Meyer on access to water, the significance of intermittent water supplies and the challenges that rapid urbanization can pose to these supplies. Then we'll speak with Sammi Levalley about her ongoing research on rural water supplies and the barriers to access relating to equitable access to water supplies. 

Erica Di Ruggiero [00:02:13] Delighted to introduce Professor David Meyer, who completed his PhD in M.S. and mechanical engineering at MIT and is an alumnus of Engineering Science The Energy Option at the University of Toronto. Before his graduate studies, David worked for Engineers Without Borders, Canada in Ghana and for engineering consulting firm called High Track Tech in Toronto. His research focuses on urban water distribution infrastructure, specifically how this infrastructure behaves in megacities in the global south. His research group works on projects, including new ways of managing and modeling mega city water networks, especially when they turn on and off frequently. These intermittent systems affect 1 billion people. He also runs the Sensing Health and Toilets Lab, an acronym he is proud of where they try to measure the health of a community from within its toilets. 

David Meyer [00:03:11] So welcome to the program. David, really delighted to host you for this episode on SDG six Clean Water and Sanitation. So maybe you can tell us a little bit about yourself and your background. 

David Meyer [00:03:26] Sure. Thanks for having me. I'm originally from Toronto. I did my undergraduate in Engineering Science at the University of Toronto. I then went to work for Engineers Without Borders, Canada in Ghana on an agriculture project. And then I did my Masters and Ph.D. in mechanical engineering at MIT, where I looked at water pipes, especially in India. And then I came back three years ago to the University of Toronto, where I'm an assistant professor in civil engineering and the Center for Global Engineering. 

Erica Di Ruggiero [00:03:56] Oh, that's great. Well, it sounds like you've had some varied experiences already. Well, as you probably know, David, the United Nations General Assembly and Human Rights Council recognized the human right to safe drinking water in 2010. So over 11 years ago now. Yet globally, billions of people are still lacking access to safe drinking water, sanitation and hygiene. So when developing ways to measure, understand and create solutions to improve access to water. To what extent are equity and justice currently being considered? 

David Meyer [00:04:26] Yeah. So that the world has made an enormous amount of progress towards improved water, improved sanitation and improved hygiene kind of over the last 50 years and over the last 15 and ten years. So that the trends are generally encouraging. And specifically, if we think about equity, it's perfectly equitable for no one to have something and perfectly equitable for everyone to have something. And in the transition, equity gets worse. And so for some of these indicators, we're in this kind of awkward phase where we're getting more and more people access. But we have to go through this transition phase where we get some people access and not others. And so I think that equity is relatively well considered as we track our global indicators for water, sanitation and hygiene. And so we do a pretty good job of tracking urban versus rural distinctions. And who gets access to these? Like who gets access to water and sanitation? There's gender based tracking. And then I often read reports that do wealth quintiles. So we look at how does this how does access to, for example, a drinking water pipe compare in the richest 20% of countries population to the poorest 20%? And so to the degree that those types of comparisons where we look at access versus a measure of social exclusion, measure equity, I think we do consider equity in how we measure our global goals. Justice is less often considered in how we measure our global goals in this domain. And when I think about creating solutions, I think often I tend to think more about increasing access rather than increasing equity. But I think there are there is a subset of solutions that are specifically equity targeted. So if we think about, you know, who is the hardest to reach and what types of special solutions might those people need, then we might have kind of an equity specific solution intervention. 

Erica Di Ruggiero [00:06:38] Yeah. So I think what you're hitting on is that ideally water should be universally accessible. However, that access can be different depending on who you are, where you live, your gender, etc. And so you need to sort of add that extra lens, which isn't without its challenges depending of course where you are. And we know here in Canada we still have issues around water access as well. I wanted to kind of move on to talk a little bit about something I know you think a lot about, which are water systems. And my understanding is. Said Intermittent water systems impact 1 billion people. So what does actually intermittent water access look like and why do these systems persist? I know you do a lot of research in this area, so I'd love to hear your thoughts on this one. 

David Meyer [00:07:27] Yeah, I do what I do for a living because I continue to be fascinated by intermittent water supplies. And yeah, they have consumed what I do for the last decade till I will talk forever about these systems. But briefly in Toronto, when you want to wash your hands or take a shower, you turn on the tap and it simply works. Most people don't think about the infrastructure if they don't know where the pipe is or where the pumping station is, that enables that basic infrastructure. But we rely on it every day, and that makes our lives better. But most cities in India deliver water only for a few hours a day. So, for example, in India's capital city, Delhi, water is delivered for 1 to 2 hours in the morning and 1 to 2 hours in the evening in most neighborhoods. So if you went to wash your hands at lunchtime, there wouldn't be any water in your tap unless you stored water. And so that's what most households do. Most households store water either in buckets or in a big tank on their roof. So if you have a house that can support a tank on the roof, you can store the water in the tank on your roof so that your kind of internal house plumbing works all day long. And so these aren't just an issue in India. They're an issue all over the planet. And in fact, it's like 21% of the world's water utilities turn their pipes on and off every day. Some cities run, you know, one day a week, 20 minutes, every third day. And so that's what intermittent systems are. I think they they inconvenience users, but they also degrade the water quality. So in Toronto, you can drink the tap water, even though the water network has some holes in it, because positively pressurized pipes push water out of them, which stops contaminants like rainwater and sewage from sneaking in. The opposite is true in an intermittent supply. But it spends most of its day empty. All the rain and sewage and dirt can sneak into the system, and it gets flushed through the system when you turn it back on. So that's one of the big reasons we care about reducing the prevalence of intermittent supply. And why do they persist? They are a sticky problem. London had an intermittent supply in the 19th century, and and there was a lot of debate about whether or not they should get rid of it. India has been trying to reduce the prevalence of intermittent supply also since the 19th century. If if you were to watch what's happening. If you were to sit, you know, pull up a lawn chair to the reservoir in Delhi and watch it on a a morning supply cycle at five in the morning like I have, what you'll see is that why do they have an interim supply is because the reservoir is empty by 7 a.m.. And but the harder question is why is it empty at 7 a.m.? Is it because we didn't put enough water into the reservoir? Is it because people use too much water to water their gardens or they wash their cars? Or is it that the pipes are too leaky? And I think depending on what city you're looking at, the answer is different. But in every case there are these big forces of water availability, urbanization and under-investment in infrastructure that kind of that combined to make intermittent systems really sticky problem. They're hard to get rid of. 

Erica Di Ruggiero [00:10:47] Mm hmm. Well, I'm glad you raised the issue about intermittent water systems, because that actually reminded me of epidemiology and the father epidemiology and the broad street pump. And looking at why it matters to understand how water is made available to us, because it's also a vector for bad things that cause ill health. So I think your examples really highlighted the potential dangers to human health as well and why it's important to study them at the source, no pun intended. 

David Meyer [00:11:21] Yeah. And I think if if we study them at the source, then their benefits are universal. And classically, the rich can always buy their way out of public infrastructure failures. And so at the Broad Street Pump, part of the innovation was realizing that the brewery, like employees at the brewery, weren't sick because they had a unique water source. And so like since then onwards we can look at differential access to the quality of water or the quality of sanitation infrastructure. And when we have centralized systems, they get to serve everyone, which means we can cross-subsidize and the water bills paid by the rich means we can afford to supply the poor. But if we rely on everyone to have their own water treatment in their basement, then all of a sudden we get really differential access to quality. 

Erica Di Ruggiero [00:12:10] Which links back to your question around equity. So one of the things you touched on that affects these intermittent water systems is, you know, a phenomenon that we are learning way more about, which is rapid urbanization. And there's a projected 5 billion people, or about 60% of the world's population that are estimated to live in cities by 2030. So what challenges does rapid urbanization pose for safe water access and what's needed to overcome them, in your opinion? Not an easy question. 

David Meyer [00:12:43] Yes. So I think that the stats are clear. The world is increasingly urban and we have this kind of increasing prevalence of megacities, so huge urban centers. And anytime you get a group of people densely packed together, they need resources from outside of where they live. And so you can think about urban ecology and our cities kind of drink water that comes from far away from them. They eat food that comes from far away from them. And that's not necessarily a bad thing because we can have economies of scale. We can bring water more efficiently into a city as it gets bigger. But today, cities cover 1% of the surface area, the land area of the earth. But they draw water from watersheds covering 41% of the world's land area. So we have this really big difference between if you draw a map and you just color in the cities versus if you color in where they get their water. And that's not necessarily unsustainable. But it certainly suggests to me that we can't solve mega cities water problems with rainwater harvesting only. We need these huge catchment areas to grab enough fresh water to deliver it to the cities. And so that as our cities become as our world becomes increasingly populated, freshwater scarcity is a problem to the degree we're living in cities. We need to be investing in centralized infrastructure to get the water and clean the water and bring it into the cities. And I think those those are expensive problems. They're not always more expensive per capita, per person. But it does mean that our cities need bigger and bigger budgets. 

Erica Di Ruggiero [00:14:22] Yeah. And also a long term plan, right? Because infrastructure, as you say, is not cheap. And the person who has to make the decision about paying for it isn't always the one who's going to reap the benefits politically. 

David Meyer [00:14:34] Sure. So, yeah, we definitely... there's a bunch of layers there, right? Like so as our cities get bigger, the contracts there they're giving for infrastructure get more and more expensive, which makes the the return on investment for an infrastructure building company to bribe an official higher and higher because a 1% of your budget line bribe becomes this huge abd huger incentive for a politician. I think that. Yeah. Ultimately systems are built and managed by people and people have incentives. So there are some social scientists in India who write about how engineers manage the system to minimize the number of people who are shouting at them. And so, you know, when you're in the water office in Delhi, what what do you hear is that, you know, you hear the list of complaints and in response to every complaint, you hear like, okay, I'll change something and you change the knob on the system. And then the next day someone else complains and then you change the knob back and you're doing this kind of constant trial and error optimization to get rid of, you know, minimize shouting weighted by political influence. Because ultimately, engineers work for politicians who can fire them. And politicians respond to powerful voters. And so you kind of have this like indirect elite capture of who's running the water system. Nickeil Anand writes about how you need political pressure and hydraulic pressure to get water to flow through a pipe. So if you ask an engineer why a slum at the top of a hill doesn't have water, they will correctly tell you that water doesn't like to flow uphill. It's harder to get the water to flow up that hill. But if on the other side of that hill is a bunch of mansions with the politicians, the answer is quite different. Water flows very easily up that hill because there's a special pump that runs to keep the politicians happy. And so, yes, our world is increasingly urbanizing. Urban water systems are really dense. They have lots of nitty gritty problems. But I also think they they have the potential of being more efficient and are really fun technical problem that I enjoy working on. 

Erica Di Ruggiero [00:16:39] Hmm. Well, I really admire your passion about that, so I'd love to talk more about this. But I have one final, like, burning question for you, if I may. So what do you think can be done to ensure the availability and sustainable management of water and sanitation for all? You know, in other words, what role do researchers like yourself and professionals here in Canada or perhaps elsewhere, what kind of role do they have in supporting this kind of objective? 

David Meyer [00:17:07] So I think kind of we talked briefly about John Snow and the Broad Street Pump and kind of the history of global health as a profession. And I think in my job at the Center for Global Engineering, we think there ought to be and there ought to be an equivalent of global engineering, where we think about how should technology and infrastructure work in emerging economies. And I think that's not a new concept. I think we're still standardizing the vocabulary. But I think there are professionals and researchers across Canada who work at this intersection of public health and global engineering. As we think about what are the kind of systems that are the necessary infrastructure to enable health. And so one of my mentors talks about water and sanitation infrastructure as the actual health care system rather than the illness care system of a hospital or a doctor's office as as one of the critical components to enable health. I think some of the recent large scale randomized controlled trials of water and sanitation infrastructure suggests that they are not sufficient. So you can't make people healthy only by giving them water and sanitation. But I think they are still necessary that it's really hard to become healthy and to raise children who are healthy and who grow. Yeah. Who grow and thrive in an environment loaded with pathogens and contaminants. Yeah. So I think I'm excited to think about water availability. I think we need more work to be done on how often does water need to be available to whom where? And I think that the sustainable use of water is important. And I would also kind of add on to sustainable management of water. Sustainable management of water infrastructure. Right. I think in in Toronto, the Gardiner Expressway is falling apart. And to me, it's kind of this symbol of even in Toronto, it's hard to invest in infrastructure that exists. And the Gardiner right is along our Lakeshore. We can see it and it doesn't look very good. How much worse is the infrastructure? We can't see that's under the ground in Toronto. And then how much worse is it in countries that have bigger and more pressing budgetary needs like India's capital? And so I think the sustainable management of water and sanitation infrastructure as well as water is really important in this system. 

Erica Di Ruggiero [00:19:30] Yeah. Now, well said. And I think the other issue in there, which was a key I think, theme in this discussion, is also stewardship and good governance and the people who are making some of those decisions about the infrastructure and how equitable it is, access by different parts of the population. So thanks so much, David, for spending some time with us today. Really enjoyed this and we really appreciate you sharing your perspective. 

David Meyer [00:19:57] Absolutely. Thank you, Erica. 

Erica Di Ruggiero [00:19:59] Thanks. Sami Lavalley is a first year PhD student in civil engineering in the Center for Global Engineering at the University of Toronto. She completed her meac in civil engineering at U of T in 2021, along with the collaborators specialization in Global Health. The goal of her Ph.D. research is to understand how equitable rural water supplies are and how that equity changes with seasonality and compares between two different contexts in the Global South. 

Erica Di Ruggiero [00:20:35] So I'm really delighted to have you on the program, Sami. So let's start to hear a little bit about yourself and your research on rural water supplies. 

Sami Levalley [00:20:45] Sure. So first, thank you for having me. I'm really excited to be here. But a little bit about me. So I'm an engineering student and I have always been an engineering student, meaning I did it in my undergraduate as well. And I found that throughout my undergraduate, I was always very interested in the why and what motivates engineering solutions, as well as the sort of technical aspects of it. And so that combined with the fact that one of my first tangible engineering experiences was through a student organization called Engineers Without Borders, which is a larger organization in the United States, but in Canada as well, has its own distinct version. Through this, I actually had the opportunity to work hands on, on small scale world water infrastructure and treatment projects. And so this was really great because this was one of the first chances I had or is one of my first exposures to this gap that SDG 6 really exists to illuminate, which is the gap in access to water, sanitation and hygiene. And so something really clicked for me. I had really great mentors and role models early on that encouraged and supported students like me who were interested in pursuing future work in that sphere. And it ultimately guided me down the academic research path. And so my research now, as you mentioned, is in rural water supplies. And so why rural suppliers not only was it something I was introduced to early through that experience with engineers without the borders, but I think it's also, in my opinion, a subsection of this problem of global access to water that demands a lot of attention. The reason, as you progress cited this, that there's this gap that still exists between rural and urban coverage. It's different for every country. But generally speaking, globally, when you look look at the problem is like a global problem. Urban coverage of water is exceeds that of rural areas. So so my research now is focused on rural water supplies in the global south, specifically in southern province, Zambia and Maharashtra, India. And we're looking particularly at improved sources of water supply and how equitable the supplies are. And so we want to look at the equity within the supplies in each of these contexts. But then taking a step back and looking at these two places together, what's the same and what's different, especially considering that one's in southern Africa and the other is in South Asia. 

Erica Di Ruggiero [00:23:07] Mm hmm. Well, it was really great to hear how formative your early experiences with Engineering Without Borders and the role of great mentors to send you down on this academic path to really address a very neglected area in with respect to water supplies, in this case, rural water supplies. You've already touched on a little bit about what you mean by improved water supplies and how equity plays a role. But did you want to add anything further to that point? 

Sami Levalley [00:23:36] Yeah, sure. So there are there are many different modes of real water supplies and the joint monitoring program, which is known as the JMP, which is the the UN's sort of way to track the progress of the SDGs, specifically SDG 6. And the JMP has something called a water or drinking water ladder and they have this for sanitation and hygiene as well. But essentially this ladder ranks water supplies based on their quality, their availability and their accessibility. And so when I talk about improved supplies, when I'm talking about our is the higher end of this ladder, so it starts lowest at surface water and water that's unsafe to consume and goes up to sort of what the gold standard is in water supply, which is pipe sources that are readily available into people's homes. And so I'm talking about improved supplies. I'm talking about the sort of higher end of the spectrum. And specifically the improved size that we're concerned about in my research are to sort of give you a picture for what I'm talking about are pipe to premise supplies and point supplies. So pipe to premise are exactly what they sound like. They're supplies that are piped to people's homes and distributed among a community. So and point supplies are typically shared supplies and by point supplies what we mean is that the point or access, like the tap that you use to access the water, is usually located in close proximity to the source of the water. And so the shared nature of these supplies, typically many people will rely on these for their water supply and the shared nature often cause queues or lines of people to form, especially during peak collection times and depending on the number of people that use them. 

Erica Di Ruggiero [00:25:18] So Sami, you kind of touched on obviously improved water supply, but I want to give you a chance to kind of think a little bit more about how equity actually plays into that. This question of needing to improve water supply, improve water supply for whom? 

Sami Levalley [00:25:36] Sure. So, yeah. So I talked about how my research focuses on approved water supplies. And I think that's I just want to explain that's because I think there's already a lot of research out there that looks at questions like because of the existence of the SDGs, questions like, what do we need to do to get clean water to people who live in rural areas? What do we need to do to make unimproved or limited sources, at least basic or at least improved? And so instead what my research does compared to these studies that exist is we're saying, okay, these improved sources are becoming available due to the emergence of the SDGs. And there's a trend that we've been seeing in rural water supplies from point supplies, which are these shared ones to trying to implement pipe systems. But what we want to explore is what do we know about how equitably these sources and supplies are being distributed among the community? And so the challenge and something I'm especially excited to explore is defining and comparing equity, because we can't really measure equity. We can't measure equity directly. What we can do instead is measure how much water a household receives so that volume that they receive and how that volume compares to the volume that they need for consumption. So what I mean by consumption is like to meet their drinking needs, their cooking needs and their cleaning needs. And so it's really interesting as volume becomes a proxy for equity. And then we can take this further and look more specifically, not only at how does this equity sort of distribute within a community, but how does this change with seasonality, particularly in periods of scarcity when supply is restricted? 

Erica Di Ruggiero [00:27:10] And so I guess one of those periods might actually be periods of drought as well, which of course leads to scarcity. And that's of course, directly related to the climate crisis. Are there other barriers or challenges building on that one that you want to speak to that particularly face people living in rural areas when it comes to water access? 

Sami Levalley [00:27:32] Yeah. So you know, when you're talking about periods of drought access to these improved sources now not only becomes a spatial problem, but it becomes a time dependent problem, I think. So what we know about climate change, and I am no expert in climate change, but what we're seeing is that the two extremes are getting worse. So in places that experience rainy seasons and dry seasons, the rainy seasons are becoming worse. They're becoming more intense then the dry incidents are becoming drier, evaporation happens quicker, things like that. And so with dry seasons, it's obvious. The problem is obvious. Supply is restricted. And so. When supply becomes restricted in a place that during, say, half the year, supply isn't restricted and you can gain access 24 hours a day, seven days a week. Now, when you know your sources are becoming more unreliable, say, for example, in a place where take a community that relies most of the year on a piped water supply system and say this pipe supply is fed by a tank. So when water is plentiful, that tank fills constantly and only time empties. It refills, and the pipe supply can supply water for 24 hours a day, seven days a week, and everyone gets the water they need. But then once you have these periods of drought and these dry seasons where water become scarce. Now this tank that feeds this distribution system, say it can only refill itself once a day, maybe once a week or even once a month, or it just completely runs out. And so what this leads to now is intermittent supply, where people receive water for only a few hours a day, a few days a week, or maybe their supply stops altogether. And so when this happens and they can no longer rely on their primary source of water, they then do what's what people refer to as source stacking, which is when individuals have to rely on their secondary or tertiary sources of water. And in some cases, these secondary sources of water are also improved. And maybe water quality and availability isn't a problem. But there is the chance that these secondary sources are actually unimproved sources which are unsafe to consume. And then you have the problem of people consuming water that is not safe to drink or they're traveling further. 

Erica Di Ruggiero [00:29:48] Yeah. So it sounds like quite a complex web and depending on the way you access your water increases your vulnerability to what kind of quality of water you can access in the face of periods of drought and other problems. One of the things I was wondering you could reflect on, you've made reference to this throughout this discussion. As a student, what is the role of interdisciplinary approaches to addressing access to water? 

Sami Levalley [00:30:16] Yes. So improving access to water is incredibly interdisciplinary. I think that yes, on the one hand, it is technical, the physical. When you're talking about the physical delivery of water and design of piped water systems, installation of wells, the limitation of treatment systems, yes, these are in their most basic form. These are engineering solutions. But then everything that goes into the planning, the implementation, monitoring, sustaining sort of side of things is when you start to see all these other disciplines and areas of expertize come into play. So for one, thinking about if you want people to, you know, start using different sources of water, this is one you have to think about behavior change. Socially, we asked the questions of how do you social status, how does income or gender identity, especially when you're looking at these shared sources, how does that play a role in access? And then also things like politics and economics. Who decides what pipes, systems or what water supply systems get implemented when who decides who pays for it? Is it the government private enterprises? Is it the community? All of these really play a role. And then, like, I mean, the purpose of this podcast, right. It's it all ultimately leads to how do you benefit the health of the health and well-being of humans. And so I think all of this is apparent in literature, for example. But taking like thinking back to my own experience with the collaborative specialization in global health, taking classes in global health and global challenges, participating in things like case competitions, working with first hand with other students and backgrounds different from my own. You really realize that many global health and global development problems are incredibly interdisciplinary and they require that type of approach. Otherwise, we increase our chances of falling short on increasing this ultimate goal of human health and well-being. 

Erica Di Ruggiero [00:32:09] Well, that's very well said, Sami, and I think the future is in great hands with students like you who are really thinking broadly and how your own discipline can work hand in hand with other disciplines to really solve these complex health, social, economic and technical problems that I think the SDGs call upon us to really address. It's been a real pleasure to chat with you today. Thanks so much for making the time. 

Sami Levalley [00:32:34] Thank you for having me. 

Erica Di Ruggiero [00:32:43] This episode has highlighted the importance of equity regarding access to clean water and sanitation. In theory, access to clean water should be universal. However, access differs based on factors like location, income or gender. This discrepancy can significantly impact a person's health and overall quality of life. Our guests have highlighted these challenges to equitable access. As David Meyer mentioned, while nations like Canada have continuous water supplies. Low and middle income countries like India rely on intermittent water supplies, which pose issues concerning water quality. Additionally, rapid urbanization necessitates the need for more and often expensive centralized infrastructure. On the other hand, in rural areas where water can be extracted through shared point supplies of water such as wells, questions about equity concern, how much water an individual or family receives. And if this is enough to fulfill their consumption needs. Equitable water access is also threatened by seasonality, especially during periods of drought. So what should be done to ensure equitable access? More work really needs to be done to ensure both sustainable water use and sustainable water infrastructure. Concerns about equity also mean addressing questions about the frequency of water supplies, including who and where they are accessed. Ultimately, as Sami highlighted, this challenge requires a multidisciplinary, collaborative effort to ensure equitable water access and thus overall good quality human health and wellbeing. 

Erica Di Ruggiero [00:34:22] Healthy cities in the SDG era is made with the support of the School of Cities at the University of Toronto, whose mission is to bring urban focused researchers, educators, students, practitioners and the public together to explore and address complex urban challenges. We would love to hear your thoughts on healthy cities in the SDG era. If you enjoyed this episode, please rate, subscribe and share. To help others find this series, you can find healthy cities in the SDG era on Spotify, Apple Podcasts and the Dalla Lana School of Public Health's YouTube page, as well as our Center for Global Health website. Join us for our next episode where we'll look at SDG8 decent work and economic growth. Thank you for tuning in and we look forward to speaking soon. Take care.