Keeping the loop in mind

Presentation at the UCT Summer School, the pdf is available on the Future Water Institute website.

Kevin asked me to present on Innovations in Urban Water Management, through talking about my house. Instead I wanted to talk about systems, and took a term from the start-up scene ‘keeping the end in mind’, as in, keep your goal in mind, what you want to achieve, or what you want to sell it for. But really, we’re working with systems, and I want to focus on where these systems, these loops come full circle.

The talking points: I’ll whizz through an introduction: I don’t like talking about myself but it’s important to show you how I got here. Then I want to pick up on a question from yesterday, how do we make this Water Sensitive Design stuff real? because this is something I spend a lot of time thinking about.

Then I talk a bit about toilets, and then I need to tell you what I do in my research so that what comes later makes sense.

After that, I introduce three concepts:

  1. Jouissance
  2. Tame is not sustainable
  3. Inverse infrastructures (or, DIY, bottom-up, off-grid, decentralised, whatever you want to call it)

After that I’ll show some pictures of my house and the Zandvlei estuary, and then because I like them so much we’ll talk a bit about toilets again. And then some conclusions and some ways to continue the conversation.




I started adult life as a biochemist/chemist. Actually I wanted to be a vet but one vac job later realised that was a silly idea, and I fell in love with biology anyway.



This was in the time of the biotech boom and I really wanted to make spider silk. I was right up there with GMO’s and stuff.



I also thought this was a great idea and I could make lots of money from it, become a biotech entrepreneur.



It took about two seconds to realise that actually we didn’t know how to make the stuff cheaply. The scientists and the engineers weren’t talking to each other. Believe it or not, this is still an issue.



So, I decided I am going to have to learn how to speak to engineers, and I came back to Cape Town to the best place in the world to learn how to get biology and engineering to talk to each other, to the Centre for Bioprocess Engineering Research (CeBER).



Very quickly I realised that even if we can make this well we need to be able to sell it. I realised we didn’t really have an ecosystem to support the industry, so I ventured into ratcheting up my people skills.



But as I started talking to people, it became clear just how connected everything was, the environment, the consequences of what we do. So that’s where the journey with TEDx and biomimicry and systems thinking and scenario planning started.



But, alas, people weren’t being as proactive as I’d like, so I started getting into politics – actually, more like governance, I think – to try and incentivise or lawfully prevent things, forcing people to do the right thing.



This inevitably led to enlightenment, because of course trying to force your will is not sustainable.





During this turbulent time I took time off to build a koi pond, because I like fish and water. This is where I learnt that koi ponds are built like sewage works, and this was beautiful to me. This was also where I realised how much nutrients there are in places we’d really they rather not be.


As I started getting better, I needed to have something to do. I needed income. So I thought, if it is the zombie apocalypse, if it all goes pear-shaped, what do I really need to know? The first thing is probably how to grow food but I suck at that and it’s probably easy to get someone else to help me.

But really, it was the realisation that our wastes could kill us. Kids die, something like one every 5 seconds, due to entirely preventable things like diarrhea. This is where I became a total shit fanatic.

After this things clicked. My research fell into place, and we coined this ‘wastewater biorefineries’. I learnt how bacteria, algae, plants and fungi can work together to make our systems work better, and currently we are expanding our knowledge into animals through worms and black soldier flies.

At the moment I’m still taking it easy and starting to move into the ‘wouldn’t it be cool if’ stage, but with the drought I’m already being catapulted again into the more fuzzy stuff.

I share this story with you not only for context. A bit of it is a brag that I’ve looked at this from a couple of angles, but mostly it’s to show the tremendous serendipity of my journey so far culminating into a time of building a house in the drought. Living in a little hut for two years with no services made me acutely aware of how much I use, and how little one really needs to be comfortable.

OK, so that’s me. I went to google streetview and my little shack is still there, look at this view!

So we’ve spent a few days talking about water sensitive design (for the readers of this post, this may feel a bit disjointed – perhaps check out the other presentations first, or trawl the web. The gist is that Water Sensitive Cities is a great way to future-proof cities, to save water while still achieving good quality of life, but it is aimed at top-down decisionmaking, urban planning, policies etc. Not very useful for the drought right now). And you asked, but how do we make this real? How can we make this move faster?

I think firstly acknowledge that this is a frustrating process. There is a real tension between getting stuff done, taking action, and thinking a bit further to what the consequences might be. It’s like your head has to be in two places at once, the whole time. But whenever this gets to me, I go back to this quote from Kahlil Gibran. It’s OK to feel pain and frustration, it means your understanding is growing. Part of moving towards a more resilient system is being comfortable with this tension.

The things we need take a long time, but we also want change now, and to be allowed to make a difference now. I use this little symbol, call it the ninja symbol, it’s the tattoo on my arm, and I use to explain whatever three things I need to talk about. Today it’s about our relationship with the city.

We heard over the past days that water sensitive design is about changing how the city does it’s planning and policy, but this takes a long time, it is a slow beureaucratic process. I am a do-er. I want action, I want to fix it now! But with age and experience we realise there is also reality. This gives us feedback, we can call this the desired outcome, but it can also be called consequences. The city’s long slow processes try to anticipate these, and for do-ers we would do well to think this through – for example by testing out our ideas at small scale, iteratively.

We’re pretty good at each of these things, in our silo’s. We’re pretty good at talking, and complaining, and strongly worded letters, and finding ways to adapt or dodge the rules. It’s the in-between spaces that need work.

We need to get better at understanding why the city does what it does. The city needs to communicate with us better. The city needs to understand that things are changing fast in reality – this is a huge challenge!

And then I was thinking, what is here in the middle? Where do policy makers become just humans interfacing with other people’s realities? Where do individuals understand why policies are the way they are and contextualise them in their daily lives? The answer, to me, is volunteering. Get involved. Today my volunteering specifically refers to the Zandvlei estuary.

I think a good way to go forward is being perpetually creatively confused. Be curious. This symbol is a Taoist thing representing “Heaven, earth, and all living creatures” and the dynamic interaction between these “worlds”. (The Base, the Path, and the Fruit is essential in Zen Taoism and is the self-perfected indivisibility of the primordial state, it requires a triple, non-dual symbol to represent it.) We did this event in 2012 and I keep coming back to what we spoke about there lately.

I’m going to keep coming back to this ninja symbol to remind us about the bigger context, to address all three things.

So coming back to water sensitive design, while I love love love the concept, I think it doesn’t go far enough. It relies heavily on city scale urban planning approaches. But to me it should be more than that, it should include our ecosystems, our culture towards water, perhaps a water consciousness?


To address this we launched AquaSavvy last year in September. By November we already realised we were coming in way too high, that we need to really, really bring it to implementable actions for the everyday person. So at the moment this is stalling a bit while I’m wrapping my head around what this involves, but you are welcome to get involved.

There were questions about toilets yesterday, so let’s just talk about that for a bit. When I was living in my shack I had internet before I had a toilet. It took planning, sure. But by the time I moved into my proper house I knew that I wasn’t going to go back to flush. I was also starting to see, as I was overlooking the vlei, exactly how our flushing habits was affecting the vlei. More on that later.

At the moment, we’re facing the possibility of Day Zero. We need 23 million litres to flush the toilets in Cape Town once a day. And I will certainly not contribute my precious 25L towards those flushes. So , what to do?

 We pee about 1.5L a day, and defecate about half a kilogram daily. The pee needs to go somewhere else. It’s a lot of liquid and low risk. So a 20L bucket should last one person a month. Once its full, pop a lid on it, park it somewhere, we’re figuring out what to do.

Carlos picked up on the potential for toilet problems late last year and has created this prototype. You can see he is in film, his presentation pics are much better.

Next up: Toilets after Day Zero – my research.

Let’s take a quick diversion to my day-job. A big part of what I do is bioprocess engineering, and through my adventures I am particularly interested in diffuse pollution, and how to convert that into value. Not just environmental value through a cleaner environment, but actual economic value as well. I believe that we just live in a time where we don’t have money to look after the environment and we risk losing the spaces when we can’t justify their economic value. While it  certainly is not ideal, I am a post-environmentalist and it is what it is.

When it comes to complex, diffuse streams, biology beats chemical and physical processes. Most engineers agree with me but use that as a reason to abandon it to nature, which effectively was what wastewater treatment was for the last 100 years. We knew that biology does *something* so we should allow space for it in a big tank, but that was it. It’s only now, really, that we are starting to really understand how it all works and fits together, so that is what I do.

Through our work we’ve coined the term ‘wastewater biorefineries’. In short it is creating value from wastewaters, using biology, this presentation may give a bit more info without getting too technical. As I mentioned, we learnt about bugs, plants and we’re heading into animals now. The ‘reactor systems’ we look at can be classified by these big technical terms below, but the bottom line is if we use all of them, we can create robust, resilient ecosystems, using many different metabolisms. I think this is particularly valuable as we’re moving into Water Sensitive Design and more green infrastructure in the urban environment.

  • Heterotrophic microbial: great control, well understood, good C removal. “bacteria”
  • Photomixotrophic: nitrogen and phosphorous removal, greater energy contribution from photosynthetic activity “algae”
  • Macrophyte bioreactor: polishing step, nitrogen and phosphorous removal “plants”
  • Solids: (dominant group expected to be fungal organisms), bioprocessing of high solids content “sludge”

My particular passion is sanitation, and I find this definition I recently came across (eawag CLUES guidelines) that really sums up the interlinking concepts really useful – Environmental Sanitation:

 “environmental sanitation” includes sanitation, stormwater drainage and solid waste management.


This definition is great because you can’t really address sanitation in isolation, these all affect each other. Same for the energy-water-waste nexus: if you use the one, you are in effect using the other. This also holds for food-transport-building… it’s the basic sustainability tenets: everything is connected, some very much so. It also speaks to limits. We can get more energy, but it uses more water, we can get more water, but it uses energy, produces more waste, etc etc. At the core, it is also about coming to terms with being part of nature, for better or worse. We are part of nature, it is not something external to us. This is not particularly a bad thing. Healthy nature in the urban environment may look a bit different than what we expect, or romanticise. Being part of nature  means we perhaps need to think more about multifunctional spaces, productive spaces, how we work with nature to find a way to co-exist well. These concepts all link in with phrases like resource recovery , circular economy, and particularly, how we

Cope with diffuse pollution as an opportunity

So with that in mind, let’s move on.

Three concepts: jouissance, tame is not sustainable, inverse infrastructures

Right. Jouissance! My favourite word (by the way, yes, there’s like huge things with Lacan and Freud and stuff. I don’t get it. So this is my entire definition of jouissance 🙂 Yes, there’s the orgasm link. Obvs.)

… a brief flash of enjoyment achieved after excessive pursuit.

The pleasure lies in the obstacles to fulfillment – but only if that fulfillment eventually arrives, and only if there are obstacles


I first learnt of jouissance in a book about Capitalism, of all things, written by Colin Cremin. The book is called “Capitalism’s New Clothes: Enterprise, Ethics and Enjoyment in Times of Crisis”.

Colin describes it as follows: “In our search for tameness and control, we want everything to always flow smoothly, but that robs us of jouissance.” To me the accumulation of wealth is about taming, making sure things are predictable, controlled. That you don’t have to wait for the sun to have light, for the rain to have water. But that also externalises the consequences.

Simply working hard and never getting anywhere, like a large chunk of us seem to do, or, conversely, just being able to buy whatever we think we want or need without needing to work for it, doesn’t make us happy. And it does a lot of harm in the mean time.

On the other hand, the fact that so many things are changing so fast is not such a bad thing. So I want to implore you to embrace a bit of wildness, in these interesting times. We need to work hard to make things better, but celebrate those small wins, have some brief flashes of enjoyment. This way, we would get further, and have more fun.

Much of what we have talked about could be seen as ‘getting back to nature’, or rewilding. Being a bit more comfortable with being bushy. One of the challenges we see with Water Sensitive Design is maintenance, and a struggle on how to list this living, almost wild thing on the governance asset registers. Wildness takes work occasionally. But maybe it’s worth it.

The thing with wildness is that it keeps giving. The thing about WSD that I love most is the opportunity for what is basically civil infrastructure to contribute to ecosystem services. My house can help clean my environment, through rewilding ourselves we can extend our beautiful spaces to where it was before we got here, while we are still here.

How do we get there? I tried to find a good illustration for this and came back to the biomimicry design principles.  Biomimicry is a design tool, but I find it a good ethos, too.


Adapting to change, and being locally responsive is particularly important, as is trying things out, playing, learning as we go – integrating development with growth. The wonderful thing is for the most part it doesn’t have to be all or nothing. Being more comfortable with change, with seasonality, with the reality that maybe we are not in control, but may well get to be in balance.

The third concept I call inverse infrastructures because I learnt most about it in the book by the same name edited by Tineke M. Egyedi and Donna C. Mehos, and learnt most about it in the online course (MOOC) on Next Generation Infrastructures. It could also be called DIY – do it yourself, bottom-up, off-grid, decentralised, whatever you feel like. The book and course takes the way we are moving to renewable energy, and how we use existing internet to make our own connectivity, as examples. Now with the drought we’re seeing it with people making use of alternative water resources. It’s basically people doing it for ourselves.

Intuitively I love this concept, it links closely with volunteering to me, but it didn’t take long to see the challenges. Sorting ourselves out is the easy bit, but what about the bigger picture? How do city governance structures generate income (conventionally through service delivery) if the affluent no longer buys those services? It’s one thing to say, well, each to their own, but especially in a country like South Africa, that is not sustainable. Inequality, in my opinion, is a bad idea. When it comes to water, there’s also risk. Remember, it is in our own best interest, regardless of your ideology – socially, economically, whatever, to keep the entire populous as healthy as you can. Dirty water for some is just not an option. Then, there’s how to manage this. Gustav Olsson from Lund University Sweden calls this MAD – monitoring, analysis and decision-making (what I used to call (process) control). Making sure that centralised drinking water supply is safe is relatively straightforward. How do you make sure 4 million people, each doing their own thing, is safe?

A better way to look at this is through ‘appropriate scale’, and semizentral,  Darmstadt, Germany describes this as ‘as large as necessary, but as small as possible.

From my work in resource recovery, I have to agree with semizentral ‘s premise that for water or energy reuse or wastewater biorefineries, I think that decentralisation is very promising, so I expect to see more of this everywhere, at every level. (Decentralisation is a term often used for service delivery for poor people, so often not popular. I expand my argument for decentralised sanitation provision in this Peri-Urban conference presentation)


House Jouissance

Kevin asked me to show you my house. This feels like showing off, but, here it is. Kevin introduced it by saying that my house was ‘off-grid with regards to water’ – Is it? Should it be? I hope that you’re already getting a bit of an idea what my answer is to this.

The basics, starting from the right, my house is small (this is a paper model I built of the site while living in the shack – the shack has the sparkles, size of a single garage, for comparison). It has the basic stuff, large roof overhangs, large deck, so it creates lots of shady bits and together with the L-shape to protect against the South-Easter it helps to regulate the temperature. It’s also insulated, windows are double glazed, solar thermal geyser. IT has a rammed earth wall on the western side to protect against the afternoon sun and driving rain in winter (here’s hoping) which is a great touch and a piece of art. Grounds the whole house (haha).

In terms of water management, it is connected to the mains, it has a rainwater harvesting pond, which isn’t great because the house is so small, and all this water goes to the ducks. I’ve just completed stormwater ponds that take runoff from the road. Then each ‘waste’ water stream has its own destination. I have a dry toilet. The shower water goes directly into the garden (no storage) to feed the trees down the slope. The bathroom basin goes to the duckweed nursery, also called dog cool-off station, there’s also a resident frog. The kitchen waste goes to the sewer, just for in case, there’s really not much of it, what with ducks and dogs eating kitchen scraps.

Here’s the pipework for catching the rain, catching the bathroom basin, and the front of the smaller stormwater pond, along with the swales, or terraces, on the east side of the house.

This is the little canal diverting some road runoff. I live in a cul de sac so I think this water is decent, but certainly not drinking water quality! There’s a treatment wetland in to help the water quality. Then, importantly, if your dam is a little pond, or Theewaterskloof, have a way to easily manage the sediment!!! Good design can solve many headaches later – I’m super privileged to be able to access the bottom because of the slope, via a big fat tap.

Guess what room this is? My favourite one in the whole house – the bathroom! The shower – this is a wet room, the whole place is available for splashies – is just outside the pic. The bright red box with sawdust pot is to the right. The house was built around the bathroom. It’s what connects the house with the land, and the toilet has really come to identify the place (no, not like in the smelly way. Tsk.)

My front garden. It might not look like much, but check it out. I had a housewarming last May, and I asked guests to bring their plant cuttings. It was important that it was cuttings, that they did not pay for, because this was going in and forgotten. The next day with a big hungover, I chucked the cuttings in their rough places and that was it. That and about a ton of mulch beforehand. This front garden has never, ever received my love or any watering. The plants are alive, maybe looking a bit reserved, but only the sourfigs are going bos at the moment. What is more, when I get round to planting nicer plants here, inbetween this, they are protected and have a higher chance of flourishing. I call this ‘pioneer planting’.

So, that’s my house.

The Zandvlei Estuary.

From living in the shack and looking out over the vlei, navel gazing, wondering what its story, and then, for my sins launching the Zandvlei parkrun, getting pulled in to the committee managing the various relationships around Zandvlei, I have learnt SO MUCH about estuaries! You thinks you know about how things work, but you don’t really know until you get involved. Looking after Zandvlei really brought home that our estuaries are the scorecards of the catchment – more realistically, the catchment’s toilets. Whatever we do higher up, ends up in the vlei.

But, on the other hand, we can look after the vlei just by what we do in our own homes and neighbourhoods. If we look at the challenges facing the vlei, by incorporating Water Sensitive practices in our homes – allowing stormwater to be campured in swales, making sure our pavements are permeable, to slow down stormwater that then takes less sediments and pollutants down with it, we can improve how the estuary works. And then spreading the word so it extends to our neighbourhoods, our local businesses…

So on the nutrients … Back to the toilet.

The case for the dry toilet EVEN in a perfect system (where the wastewater always gets treated well and there is never sewer overflows…)

  1. We need to recover our nutrients to go back to the soil, for food security, soil health (this could work in both flush and dry, but see point 3)
  2. Producing nitrogen and mining phosphorous the way we currently are, is really bad for the environment. We have too much of it in the cycle, it’s imbalanced, and the NOx (half burnt nitrogen compounds, to oversimplify) is a terrible greenhouse gas (we can recover and change this both for flush and dry, but see point 3)
  3. Dry toilet waste is more concentrated, so easier and cheaper to recover
  4. Dry toilet infrastructure is cheaper than flush infrastructure. In a country like South Africa we can give more people better toilets if we don’t use flush at all. My opinion.
  5. The most important one for places like Zandvlei: Effluent even from well managed wastewater treatment works = eutrophication

On the other hand, dry toilets aren’t that bad. (By the way, now that #DayZero has truly taken off as a possibility, dry toilet does not mean the vile, the despicable, the stinky, long-drop, or pit toilet.)

When I talk about a toilet, convenience is assumed. As it should be. Dignity, Convenience, safety, of course. But is it assumed that this can be delivered only by white ceramic flush?

Things I want in a toilet:

  • Good natural light
  • Indoors
  • No flies
  • No smell


Nowhere in this list am I bothered by if it’s flush or dry. 

There are so many designs available, and the lovely thing about dry toilets that don’t need that engineered S-bend to keep the stinky water at bay, you can design the thing exactly like you want! There are dry / extremely low flush / foam flush toilets available that are virtually indistinguishable from the white ceramic flush toilets, if that’s your thing.

Let’s conclude this from another angle.

If rich people are not willing to use the
most sustainable sanitation systems,
how can we expect poor people to use it?

Conclusions, continuing the conversation

It’s time to create new cultural norms, that is built around thriving in relationship with our wider systems, more than coping with scarcity.

We need to change behaviour, not the source of where we get our water from.

Long term plans are the best way to prevent emergencies. This is out of the hands of individuals. We need the bigger plans for economically attractive, vibrant, liveable cities, to have secure systems. But we can still create a lot of change ourselves.

So, off-grid? Is my house? Maybe a little bit in the conventional sense of the word, but not really – everything is connected. Should it be? No.

The bottom line, also, is that

The things we need to do to avoid the bad scenarios, are the same things we need to do once the bad things have happened, to adapt and survive.

The informed route forward looks the same regardless.

Let’s keep talking. As Future Water we have a Bridging Waters conversation series to thrash this out playfully, join the mailing list to stay in touch, and AquaSavvy is designed for this.

2 Replies to “Keeping the loop in mind”

  1. Good work Bernelle -like the insouciance of your blog and the insightful thinking. would like to visit your house in Lakeside sometime to help with ideas for my own domestic tinkering in Kommetjie and moving a reluctant family towards a compost loo. My earthworms are currently involved in an experiment in that regard.

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