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AnimalsTranscript
00:07These expansive lands in northern Kenya have been home to nomadic tribes for thousands of years.
00:18If we go to the country, we might have a chance to see the livestock.
00:22Down this way?
00:25But as recently as 60 years ago, this place was a dense, flourishing forest.
00:31Now, it has dried into a resource-poor, parched desert.
00:36The area is really suffering the impact of drought.
00:41The people of Takana and their livestock are on the front line of a battle beginning to play out all
00:47over the world.
00:48A battle to secure water.
00:51Growing populations, water mismanagement and climate change mean that by 2025, half of the world's population will face water scarcity.
01:02And global tensions are rising.
01:05I'm Professor Hannah Frye, mathematician and writer.
01:11I want to explore why the world is toying with catastrophe over dwindling access to water.
01:17And whether technology can help secure our future needs.
01:36This is part of the Rift Valley, sometimes known as the Cradle of Humanity, because this is where the earliest
01:43human-like fossils have been found, some of them at least.
01:46And the people who still live here, they have a very nomadic lifestyle.
01:50They move around looking for pasture in search of water.
01:55Searching for a supply of fresh water used to be the ultimate priority of our ancestors.
02:01But today, over half of us live in towns and cities, where we expect the water to come to us
02:09instead.
02:10And while it might seem like an unquenchable resource, every drop that we use is taken from an interconnected cycle
02:18that's responsible for all life on Earth.
02:23Earth, remember, is a giant, rocky, wet blob floating in space.
02:28All of the water that we have ever had and ever will have is already here, cycling endlessly around our
02:35planet.
02:35When rain falls, it goes into rivers and lakes, but it also seeps into sediments and cracks, forming these vast
02:42underground aquifers.
02:43Out at sea, water evaporates, becoming clouds that drift back over land to fall again, becoming a new store of
02:50fresh water.
02:51This cycle has been happily stable for thousands of years.
02:56But now, eight billion humans are interfering.
03:00We are sucking up water from the rivers.
03:02We are damming them, blocking off the supply downstream.
03:06And we have extracted so much water now from deep underground that we've managed to shift the Earth's rotational axis
03:14by about 80 centimetres.
03:17And on top of all of that is climate change.
03:19We have got more intense rains, more erratic weather patterns and prolonged spells of drought.
03:26The amount of water on Earth, that hasn't changed.
03:29But where the water is, and when and how it moves, is becoming more and more unpredictable.
03:43The people here were never strangers to drought.
03:47But now, it is a constant, unrelenting concern.
03:52Joel and June work for Practical Action, an international development group that is responding to the crisis in the region.
04:01We identify areas with serious challenges in terms of access to water, access to food.
04:08We chose this place because of the problems that the community was experiencing.
04:15Here, the men practice pastoralism, a tradition of roaming across grasslands,
04:20raising livestock to keep their families fed.
04:23But this is a way of life reliant on rain for pasture to grow.
04:27And that has left these people among the first victims of the effects of climate change.
04:33Can you remember what it was like when he was a boy?
04:36How have the rains changed since then?
04:57The pressure on the pasture, does that ever result in conflict?
05:01How do you act?
05:07Is he angry about this? About how things have changed?
05:50There are now, routinely, violent clashes over livestock, water points and pasture.
05:57Hundreds lose their lives each year.
06:00The strain is not only felt by the men responsible for herding the livestock, but also by the women and
06:06girls of the community.
06:09Water is a function that is culturally left for the women.
06:16They used to go to the river, which is more than 10 kilometres from this place.
06:23When the rivers run dry, women and girls have to dig what's called a scoop hole to extract the water
06:29saturated in the riverbed.
06:31How deep are we talking?
06:34Ten metres?
06:35Yes.
06:36Where you're having three people, from one person to the other, handing over the buckets of water, you take from
06:42me, you take from me, up to the surface.
06:45Wow.
06:45And most of the time, it collapses on them.
06:48Collapses in?
06:49Is it only sand?
06:50Yes.
06:51We have had incidences where the scoop holes do collapse and we have fatalities as a result.
07:00Around here, getting hold of water means accepting these unthinkable risks.
07:06Something practical action have been trying to change.
07:09These storage tanks are full of water, drawn up from deep underground aquifers using solar power.
07:16It's enough of a supply of water to mean it can be used to grow crops in the rich soil.
07:23Laying down roots in the most literal sense means that these women are no longer nomadic water carriers.
07:30They are farmers.
07:32They are farmers.
07:33And these allotments have become the centre of an astonishing shift in this community's livelihood.
07:38They are farmers.
07:45They live in the middle of this community, and they are farmers.
07:47They are farmers.
07:50They are farmers.
07:53We all do周 pod to help us.
07:53They are farmers.
07:55They are farmers.
07:56They are farmers.
07:56We are farmers.
07:57We are farmers.
07:58Susan is one of these women who grows and tends to her crops in the allotments.
08:02The harvest gives enough to feed the community with leftover produce the farmers can sell, earning
08:07money to pay for school for their daughters and your children could they go to school before
08:27and how about for you how has your life changed
08:41they used to face malnutrition problems a lot as women so our life has changed greatly if you can
08:48see from how she's looking because that's how she has said it she's glowing i mean there is quite a
08:56lot of work now for for the women though right i mean if you're taking care of the water but
09:00now
09:01also the food has it changed the power dynamics slightly between the women and the men here
09:19the people who live here their lifestyle is having to change it's having to adapt to the
09:23changing climate but i think there's something amazingly positive about what can happen when
09:28you give a community access to a sustainable supply of water i think the only question mark
09:35that i'm left with is how long term this solution can be i mean the borehole could run dry the
09:44the
09:44solar panels could break there could be all kinds of things that happen that are totally outside of
09:49anybody's control and i do wonder what happens to people who live in places like this in that kind of
10:01future today over 2 billion people live with some degree of water scarcity and this could cause 700
10:09million people to be forced from their homes by 2030 but in the regions most affected access to water is
10:17now more than a humanitarian issue it's a threat to national security
10:29danish masood alavi is a peace and security technologist interested in how water deprivation
10:36is impacting different regions water is this resource that we all need of course and it's the kind of thing
10:45that can easily become a source of contestation it can be used as leverage it can be the very cause
10:51the root cause of conflict so in the context for example of the tigris euphrates basin turkey is
10:57damming the river upstream but that's having downstream consequences in a place like iraq where now with
11:03the absence of water you're having significant social unrest because temperatures are rising quickly
11:10and the water flow is not the same in a way then i mean i think that the idea of
11:16say oil being a source
11:17of conflict i think that that makes sense to a lot of people but the way you're describing it is
11:22that
11:22that water is this absolutely critical pinch point almost nothing works without water nothing at all
11:32to predict where water scarcity could lead to conflict danish is using data collected from space
11:40nasa's grace mission has two sister satellites which orbit the earth precisely tracking their
11:46distance to one another but this distance is affected by gravity so as water saturates the ground
11:53the density and hence gravitational pull changes causing the satellites to move closer together or further
12:00apart tracking this over time means that scientists can construct maps of where water is moving around the
12:09planet so if we look at iraq here this is how things look in 2007 now when we look at
12:20it nine years later
12:21in 2016 it's a sea of red we're able to look at how quickly water is being depleted in a
12:29particular country
12:30and we take all that information that's freely available to us as raw data and compare it to
12:36all kinds of other information so for example one of the things we're interested in is social unrest
12:42and in particular how social unrest correlates with how quickly water is being diminished and what do you
12:49find we find that there is a correlation in many instances in a situation that's already stressed
12:55already difficult you add in issues around water and it makes things worse danish's aim is to provide
13:04governments and authorities with data to better equip them for where conflict may arise in the future
13:11so when you're able to have these kind of empirical ways of measuring how much water is there you can
13:17have a conversation that's grounded in a set of facts different countries have different ideas around how they want
13:23to use water and it becomes a sovereign matter understandably a sovereign matter on a resource
13:28that's not i mean who owns it exactly and we're going to see more and more of these challenges as
13:35climate change begins to affect us more when you look at the amazon rainforest 20 of the evaporate from
13:43the amazon rainforest falls on u.s agricultural land whose is it right the food security of the united states
13:51is directly tied to the amazon rainforest if someone comes along and says well i'm going to chop down
13:58all the trees that has a direct consequence on u.s food security the level of water stress is only
14:06increasing and the need for sharing resources is becoming more and more acute
14:15when you're using water as we all are without necessarily seeing the much bigger picture
14:23i think it's quite easy to forget this view that danish is offering there right this very stark image
14:31of us from space with this limited and finite resource that will move around whether we want it to or
14:39not
14:43it isn't just water scarce conflict zones that are suffering even here in london a city built on a
14:50river trying to control this wild natural resource is becoming a problem dr anna miech is an expert in
14:58water infrastructure systems if i turn on a tap in london where does that water actually come from
15:04around 80 percent of the water in london is coming from the river thames and then we have around 20
15:11percent of water coming from the subsurface from the groundwater resources london's water system is fed
15:18by rainfall groundwater and rivers that supply a network of reservoirs from here water is sent to
15:26treatment plants before being pumped into the taps across the city the sewage is then treated and made
15:35safe before being discharged back into the environment the entire cycle relies on rainfall to replenish the
15:42supply so that london can continue to operate but this is a system that was originally built for a
15:50very different time the reservoirs date from the beginning of 20th century the sewer system has been
15:58built the victorian area yeah exactly the 1860s and we are now dealing with different weather patterns
16:04which bring different amount of water at different times and bigger extremes and bigger extremes with
16:10the very different city i mean if we look around us i mean just see how many construction sites are
16:15around us one of the biggest dangers is flash flooding the aging infrastructure cannot cope with the more
16:24extreme rainfall that's feeding into the already overburdened sewage system and while too much water
16:32is a big problem for the city now not having enough is a growing danger for the future i guess
16:39we're
16:39quite lucky in london that it rains all the time well it rains but it's actually relatively dry parts
16:46of the uk southeast of england you know london are at a quite high risk of of droughts
16:54surprisingly southeast england has a lower average rainfall than perth and south sudan combining those
17:01twin issues of growing demand and longer periods without rain mean that even here in 25 years the
17:08reservoirs risk running dry one thing that really struck me about what anna was saying is that
17:14drought and flooding are two sides of the same coin it's essentially the same problem that you're
17:22dealing with the stress is that this water system is under and the way that that's only going to get
17:27worse i can't help but wonder whether that would be much higher on the political agenda if it was
17:34the other side of the coin that we were worrying about if we were concerned that one day you would
17:39turn on the tap at home and there wouldn't be any water there at all day zero the day the
17:47taps run dry
17:50mexico city bengaluru and cape town have all been pushed to the brink as the city's reservoirs and
17:57wells fell to critical levels forcing emergency action to be taken to save lives
18:05but it was over 60 years ago that singapore fell victim to day zero its residents no longer had
18:13access to a single drop of clean water and ever since securing the country's water has been a national
18:20priority where do you rank in the world in terms of how water stressed you are we are as dry
18:37at the
18:37middle east harry sear is an engineer for singapore's national water agency and has been solving the
18:46country's water problem for nearly three decades people say if you're in the tropics you are blessed
18:53with a lot of rain right and surrounded by water yeah just plenty of water it rains every few days
19:00and
19:01always should be ample water the issue in singapore because we are so small it's a land constraint issue
19:07we don't have luxury like countries like uk or us where you can afford to have huge lakes and
19:13reservoirs you know ours is a tiny place this lack of space led singapore to develop new water a project
19:23harry has been working on since its inception every drop of water is precious to us we collect every
19:29drop water after it's been used clean it and return back into the system like london
19:36singapore gets some of its drinking water from reservoirs and sewage is collected treated and
19:42released back into the environment but here treated wastewater is also pumped to new water factories
19:49where it is purified and then sent back to feed water hungry industries and top up reservoirs creating an
19:57artificial water cycle this is high level magic come on then tell me the high level magic okay a magician
20:08doesn't usually reveal his secrets but okay fine so this is the first stage microfiltration just imagine
20:15a filter the water molecules can pass through but the larger contaminants cannot does bacteria get caught at this
20:22yes yeah bacteria gets caught in this stage
20:28microfiltration is the first step of the three-stage purifying process the second step reverse osmosis
20:35forces water molecules through tiny pores in a membrane filtering out larger contaminants
20:42and finally a blast of uv radiation kills any remaining microbes that might have squeezed through
20:48and it's ready to drink i think i sort of imagine that you'd be like chemically treating it you'd be
20:56like adding stuff to the water but you're really just doing fancy sieving that summarizes it perfectly
21:04fancy filtration yeah and you're left presumably with water that doesn't taste like sewage in the end spot on
21:11well there's only one thing left to do how long ago was this sewage 24 hours ago this was probably
21:19still in the sewage
21:27how's that just tastes like water it is just water that is amazing
21:33currently the national water agency say that reclaimed new water supplies singapore with about
21:3940 percent of its water needs and they hope to provide over half of it by 2060. in the decades
21:46since singapore hit day zero it has learned the importance of self-sufficiency they're no longer
21:52beholden to the unpredictable movement of water i have to be honest with you i was a little bit squeamish
21:59before coming here but but it's very persuasive how quickly did people get on board if in the uk
22:05suddenly the government says by the way we're going to put sewage water back into the tax what happened
22:10there i think in the element of trust although it's high it's something that's easy to lose
22:17one mistake overnight is going that does really strike me as something that you've sort of cracked
22:22though that people here do see the value of water the principle is that water is not only for drinking
22:28it's for for life right if you valued water then things will change your philosophy your thinking
22:35your approach all will change
22:39the future of the world's water supply is uncertain we will continue to be faced with too little too much
22:48and battles over who owns it technology can help us to find it and hold on to it
22:56the most powerful change we can make in our relationship with water might just be the way we
23:01think about it i think for a lot of people saving water feels like a bit of a wishy-washy
23:10environmental
23:11concern you know like not using plastic straws and i don't think we've realized certainly not in the way
23:18that singapore has that water is this issue of national security concern and here they had to go
23:28right to rock bottom before they changed their ideas about the value of water as a resource and and now
23:34the only thing i'm hoping for is that the rest of the world learns that lesson before we get that
23:40far
23:49so
23:53you
23:55you
23:55you
23:56you