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Already and this is the Daily This is the Daily OS. Oh now it makes sense.

Good morning and welcome to the Daily OS. It's Sunday, the third of August. I'm Billy fitz Simon's I'm.

Sam because Loski.

Happy Sunday, Happy Sunday. We are here to talk about water. Now.

Have you ever thought about where your water comes from?

Well, maybe you did when you were in your year ten geography class.

But in case you were sick that day or you need a refresh, get it.

We are here to have an in depth look at the cycle of water and trust us, it's more interesting than it sounds. We asked you what you wanted to know about where your water comes from, and today we are answering those questions. And just a quick note, as you heard at the top of this episode is sponsored by Sitneing Water, but they have had no influence over the content of this episode.

Sam.

Before we get started, I actually want to start by asking you a question, where do you think water comes from?

I have this idea in my head that the ocean gives us water that's treated, comes out of the tap, and we drink it. That's essentially my understanding of the source of our water. I actually sometimes think that when I'm in the ocean, I can't believe I'm going to be drinking this.

You're just having a big old golf of seawater.

Yeah, yeah, I'm young.

Well you're pretty close. That is how it happens for some of the water.

But then I think about rain. Yeah, get confused.

About rainew, I will explain it. It's going today.

Well, I think the first thing that we need to establish really is whether there's enough order forever and if water is a finite resource or if it's this constant kind of topped up pile of pile of liquid.

So it's not the latter, it's a former. It is a finite resource.

So all the water on Earth is all the water.

We have, all that rain.

It's a cycle, though, so I'm sure you know from uten geography that water comes to the earth and then it goes back up to the sky.

That's a very simple.

Wow, that's a bit of a that's a bit of a mind blowing idea.

Yeah, so how much water we have today is the same amount of water we had ten years ago or one hundred years ago, or when the dinosaurs were on Earth. It's all the same water.

I cannot get my head around that. So what about droughts then, well, that's.

When there hasn't been enough rainfall. Let me explain a bit more.

So. Obviously, the water moves around a lot, so it's going through this continuous process of moving between the earth and the atmosphere and then back again. And that's all part of the natural water cycle. So you're thinking about evaporation and precipitation, that whole process.

Okay, In terms of.

Drinking water though, which is what we're talking about today, A fun fact is that only one percent of the Earth's water is easily accessible to become drinking.

Water, right, And what's the other vast majority of it?

Then?

So ninety seven percent of our water is salt water, and of the three percent that's left over two percent is locked away in ice caps and glaciers.

And so the question then is you've got this one percent of water that is water that we can actually drink or that is accessible to be drunk. How does that become drinking water?

So there's a few different ways. The main source of water in Australia is from rain water, right, Okay, So whenever I'm with you and it's rating, you always say it's good for the farmers.

Great for the farmers.

Always say that.

And the first thing I thought of when you said that sentence is the fact that you listen to rain when you're working when you need it. When Billy needs to lock in, she puts on the rain soundtrack.

I look it up on YouTube and I just listen to.

Rain all day. It's a very significant part of both of our lives and the farmers.

And the farmers. But the next time it rains, you can say, well, I look forward to drinking this sometime soon.

So explain to me that process of it falls from the sky. How does it land up in a tap?

So obviously you need something to catch the rain water, and so that's what dams and water catchments are. Now this might seem like a silly or obvious question, but Sam, do you know what a dam is.

I think about it as in the big bathtub of wherever you are. It's the bit near the drain at the bottom. What like, it's the bit at the bottom that collects all the water that comes from all the the bath Yeah.

No, wait, you're really far off.

Like all the water runs down all the hills and like through all the different channels and collects in a certain point.

But it's not like in your house. No, that's what I thought you were saying.

No, oh my gosh, No, I don't think a dam is a bathtub.

You think it's like a big catchment in a reserve somewhere.

Yeah, in the great house that is Australia. Okay, Well, the dam is in the bathtub of the country.

Okay, you're more close than I initially thought you were. But it's actually the physical wall like structure that holds the water back once it's caught in that catchment, and it keeps it in this protected space. I'm like above, yeah, kind of like above, But my brain is too literal for your metaphors today clearly.

And so then it collects in this bath slash dam, and then the question becomes, I guess how much it can collect? And that's where I guess rainfall becomes really important.

Right, Yes, so rainfall is very important for the dams. So, like I said, the dams are specifically in place to catch the rainfall and turn it in to safe, clean drinking water. Now, once it's in the dam, it then goes to water filtration plants, which is the process where

How does housing growth fit into.

That, Well, it means that because you have more people into more tightly packed areas, there's even more water needing to go to those places.

There's a greater stress on those really metropolitans supplies.

And this particularly comes complicated during droughts. So in Sydney, for example, in the last drought, our water supply dropped by fifty percent over two years. So that was from mid twenty seventeen to feb twenty twenty, and as these extreme weather events become more common, we can't rely on rainfall alone to sustain a city like Sydney's water supply.

And that's I guess where we need to be bringing in further processes that don't just rely on the rainfall that's coming into the dam. Are there other sources that we can get water from? Should there be another couple of years of drought for example.

Yes, the ocean, I know it well.

Yes, so seawater can be used, as you said at the start, as a drinking water source, but it needs to go through a different process to what it goes through with dam.

So it needs to go through a specific process.

Do you know what it's called desalination? Desalination plants that are always talked about in politics and in kind of government decisions.

Yes, So desalination removes salt water and impurities from the sea water to produce drinking water. Now, Sam, you said at the start that this was the main way that you thought we get drinking water, and it can be so how dependent we are on the desalination process can change depending on how other sources are going so for example, if we're in a drought like I mentioned before, there

And so I guess the point there is it's meant to take a little bit of pressure off the dams in terms of how important they are to the water infrastructure exactly.

And again comes back to being less reliant on rainfall and finding other sources to get safe drinking water.

And is that the case around the country.

So it varies state to state.

Somewhere like Perth, for example, thirty five percent of their water comes from the desalination process. In Sydney it's up to fifteen percent. Melbourne has actually just committed to restart using desalination because dam levels are dropping.

Now.

Another rainfall independent resource is something called purified recycled water. So that's when you turn waste water into drinking water and it goes through a huge process to of course make sure that it's absolutely safe to drink. Now that is used around the world. So in Singapore, for example, about forty percent of their water demand can be met with recycled wastewater. Now it's not currently used in Sydney, but in Perth it contributes up to five percent of their drinking water.

Fascinating. And so water is going through these various processes, whether from a dam or from the ocean or from a recycled facility. It goes through a filtation process or a desalination process, and then it comes through the taps, right.

Yes, and so how does it get to the taps?

You turn it on, You turn it on, but before you turn it on, it has to go through pipes. Yes, Now in Sydney there are twenty three thousand kilometers of drinking water pipes and that's just drinking water pipes, so there are also wastewater pipes. You combine drinking water pipes and waste water pipes, which, to be clear, they don't they're very separate. But if you did combine them, you could wrap the earth one and a quarter times. That's

And are there ways that we know that nothing along all of these steps and processes is actually going wrong.

Yeah, there are extensive processes throughout making sure that at every stage there are tests happening to make sure that it's clean and safe and everything's happening as it should.

The thing I really enjoy about these types of stories is that it's almost a subconscious habit. We have to turn on the tap and to get water, and we know that that's not the case all over the world. But also there's a responsibility that we have as tax payers to understand even how all of these systems come and work together. And when we put this out to the audience, it was clear that people had this real

Yeah, and so this goes back to what we were saying before that there is this real need to move away from rainfall dependent water resources. Again, that's because with more severe droughts it will lead to lower down levels and reduced availability of water. And so the way you diversify is through options like desalination, or through options like

Right, so there's the real sense of trying to preempt this challenge should be a couple of decades in the future.

But it kind of already is happening now right as well.

There was another question that I think was one that we've all thought of. Why does water taste different everywhere you go?

Okay, this is my favorite question because I think about this a lot.

There is one.

City in Australia where when I traveled there, I couldn't believe how different the water tasted. And you will notice when you move from state to state or city to city, the water does taste different depending on your location. And that's because of the different sources of where water can

Tastes, and chlorine would be one of the key ingredients that a lot of places add to water.

Right, Yeah, chlorine is an interesting one. I don't think I think I ever fully understood that chlorine is actually added to drinking water at very small levels. I don't know if you've ever been in a chlorinated pool and accidentally had a mouthful of the pool water doesn't exactly taste good.

No, the yearnine swimming carnival drinking experience is not one to be chosen by voluntary choice.

But obviously the amount of chlorine in a pool in your unine swimming carnival is very different to the amount in drinking water. And there is a limit on how much chlorine can be added to drinking water.

And why is chlorine specifically an important part of the mix.

So it's actually really important to be added to drinking water to kill things like water borne disease causing microorganisms like bacteria, So you can think of it like a protectant. And chlorine has a really long history of safe use in drinking water around the world and has helped to virtually eliminate water borne diseases in developed nations like Australia.

It's always interesting reading about some of the projects around the world to uplift water infrastructure. I know the Gates Foundation, for example, is very very involved in providing clean water to different parts of Sub Saharan Africa and them talking through always how important it is to have various minerals and chemicals that go through our water to really ensure that some of those preventable diseases aren't there for everyone to drink.

And that's when making sure that it's being tested at every stage is also.

Important, exactly, and that's really interesting. It's always so amazing to kind of peel back the cover of how our society works. I definitely found that when exploring what happens to our Pooh, this is now a really interesting lie of what happened.

We got through the whole podcast without you mentioning that it was valuable journalism, as is this.

This is so interesting to think about when you turn on that tap and you get a bit of h duo that comes through. Thank you for taking us through that, thank you and thank you for joining us on the daily os. This Sunday water water everywhere, but not a drop to drink, but we do have another podcast to listen to tomorrow morning. We'll be back in your ears then. Until then, have a beautiful rest of your weekend.

I have no idea what you just said, but bye.

My name is Lily Maddon and I'm a proud Arunda Bungelung Calcuttin woman from Gadigol Country. The Daily os acknowledges that this podcast is recorded on the lands of the Gadigol people and pays respect to all Aboriginal and Torres Strait Island and nations. We pay our respects to the first peoples of these countries, both past and present.

Now, if this episode got you thinking more about the water that comes out of your tap, you aren't alone, and Sydney Water is thinking about it too. As our population grows and our climate changes, the way we manage, protect and deliver water is becoming more important than ever. That's why Sydney Water is investing in smarter, more zillliant systems to make sure our drinking water is safe, sustainable