- 1 week ago
From high-tech scans to citizen science, Kenya is scrambling to plug a shortfall in the capital's water supplies. Plus: The African city that has beaten drought for decades with trailblazing solutions.
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00:07we can actually make this country water secure that's where the government needs to put its
00:11money in some parts of the world it's easy to take fresh clean water for granted for hundreds
00:17of millions of people elsewhere it's still a pipe dream the good news is that more and more people
00:24are getting connected to safe water services and at the same time our cities and our water use are both
00:32exploding so how do we make sure there's enough water to go around well maybe nairobi has the answer
00:44this helicopter is off to find future sources of water for nairobi
00:51hydrogeologist samuel kamaun and his team are mapping the groundwater reserves in the region
00:57in a large-scale project the helicopter is towing a high-tech electromagnetic measuring system
01:03that can peer hundreds of meters below ground nairobi is drilling ever deeper to access drinking water we
01:11have that trend where we are going deeper it is estimated that we are going almost six meters deep
01:21every 10 years so it means we are exploiting the topmost layers of the aquifer and now we are now
01:30going to access the deeper most layers of the aquifer the kenyan capital with its population of six
01:41million is growing faster than its water supply reservoirs in the abodea mountains north of the city
01:48supply most of nairobi's drinking water but demand is rapidly growing nairobi's daily water needs amount to
01:57935 million liters right now nearly 300 million liters of that are missing each day
02:08water kiosks are trying to bridge the gap with water from bohos for example
02:15that's why the work of researchers from the regional center on groundwater resources is becoming
02:21increasingly important the athikapiti plains about 60 kilometers from nairobi are one of the key
02:28groundwater recharge areas for the capital air measurements have identified a promising site
02:35using electrodes the scientists are testing to see if the groundwater here is usable but the initial
02:42results are sobering based on the in-situ parameters particularly the ec this water is safe for livestock
02:51use but for humans the water requires a treatment to lower the salinity to level of 400 to 600 milli
03:01micro siemens per centimeter the researchers are collecting water samples for laboratory analysis
03:07the results show that the groundwater is more polluted than initially thought part of the problem is
03:13fluoride coming from the volcanic rocks that surround nairobi in high enough concentrations fluoride can cause
03:20dental fluorosis and bone damage worse still in some areas contaminated wastewater has seeped into the
03:27groundwater the other issue is to do with the nitrates uh majorly emanating from issues to do with
03:32waste management also there are also very many issues to do with ecoli because of the
03:38water contamination from the sewerage this spring is fed by groundwater the area where mama
03:45rehab draws her water has been laid out with concrete to prevent contamination and keep the kerarapon
03:52neighborhood on the outskirts of nairobi from encroaching further on the spring this also helps to keep the
03:59nearby mbagathi river clean a group of citizen scientists regularly tests it for pollutants today
04:06they want to find out whether their efforts to educate local residents have borne fruit mama
04:13rehab for example used to do her laundry right in the river today she uses a tub when she pours
04:20the
04:20water away it still seeps towards the groundwater but at least it's somewhat filtered by the soil
04:26the citizen scientists are keen to see if the protective measures are having an effect after adding a
04:53agent the water sample changes color then they compare it to their reference to stability is
05:01increasingly becoming good which is a very good evidence to show that the communities are also
05:07taking part in conservation of our water beyond that we also did nitrates which shows uh averagely that
05:14our water is also being polluted by agricultural runoff armed with these hard facts they're working with
05:22authorities and local residents to develop countermeasures this also shows that there's a lot of use of
05:28chemical uh chemical reagent when it comes to agricultural use and so we use this evidence to
05:35ensure that we are able to come up with evidence-based advocacy and solutions that are informed from science
05:40industry is also contributing to the pollution of rivers and groundwater stricter environmental regulations
05:47are now forcing many companies to treat their wastewater more effectively many with help from this local
05:55company recycling water safely is expensive but pavan gadvi's systems help to significantly reduce the cost
06:03his company kanku takes high performance filters that have been discarded and reconditions them for less
06:10demanding tasks we were able to initially just try and find out whether it was feasible to take end of
06:16life reverse osmosis membrane which is very common in kenya because of the floriculture industry all the
06:22different manufacturing industries and we wanted to see whether we could repurpose and remanufacture them
06:28they have installed over 100 such wastewater treatment plants across kenya there's a lot of opportunity
06:34for reusing the water waste water is a 99 pure water it's a one percent contamination there generally
06:42so it's possible to recycle entire water the company is preparing for their most complex project yet
06:49a local tannery needs to clean up its highly polluted wastewater quickly or the environmental authority
06:56will shut them down it's a big investment but does have advantages
07:01i can find water that i can reuse because now you'll find i'll save a lot on the operational costs
07:09and also the fresh water that i was buying before that i was taking into my operations now i can
07:16reuse it
07:17the first components of the system are being delivered treating and recycling wastewater is not cheap
07:24a basic system can cost between 700 and 3000 us dollars per month to operate but recycling alone can't
07:33make up for the shortfall so more and more water is being drawn from underground nairobi has 2600 registered
07:43boreholes there are likely to be many more so alternatives are needed make use of the rainwater harvesting
07:51or maybe other sources to complement what you have from the boreholes because if you over rely on the
07:57groundwater and there is little getting recharging to those aquifers in the near future you you're going dry
08:08the paradox is that during the rainy season the city and its environs are often hit by floods most
08:16recently in march 2026 millions of liters of water just drain away a missed opportunity according to the
08:26chairman of the world drillers association cornelius chepsoi wants some of those flood waters to be
08:32diverted to replenish the underground reservoirs that's where the government needs to put its
08:38money don't allow nairobi to be destroyed by floods give us a chance to drill boreholes for reverse
08:46purpose and i call it reverse because instead of abstraction we would be injecting it back to the
08:51ground for someone else to abstract it later we can actually make this country water secure the kenyan
08:59government is already pursuing this idea the electromagnetic measuring system is being used
09:05not only to locate new groundwater sources but also to identify the places where reserves can be replenished
09:14and so today i'm 40 kilometers away from the capital narobi and behind me is manguo swamp which
09:20is a very important freshwater wetland a critical recharge area for the narobi aquifer it also supports
09:26a lot of bad life i think you can see from the background uh like uh macawar ducks and ibises
09:31and so recently the center on groundwater resources conducted a nice sort of study here and realized
09:37that this water is connected to hondiri swamp which is uh 20 kilometers away from here through other
09:42groundwater channels and so these two swamps support millions of people who depend on boreholes for their
09:48livelihoods and so it is very very important to protect wetlands like these ones from pollution
09:52because the quality of the surface water has a direct impact on our groundwater water water stress
09:58is growing in many cities in africa and around the world as human caused climate change disrupts weather
10:05patterns but some population centers have been dry for centuries so how can you optimize your water supply
10:14if that supply is virtually zero this city looks much like many others but in fact it's unusual inhabitants
10:24drink their own wastewater namibia's capital vindhook is one of the driest regions in sub-saharan africa
10:32so wastewater is treated and reused directly rather than first being pumped into rivers around 80 percent of
10:39namibia is arid or semi-arid it rains on only about 55 days a year while the sun shines for
10:47nearly 300
10:48water here has never been something people take for granted in fact in 1968 vindhook became the first city
10:56in the world to turn treated wastewater into drinking water today this plant provides 21 million liters daily
11:04that's over a third of vindhook drinking water the water goes through multiple treatment steps it's filtered
11:12purified and tested until it's safe to drink
11:17the city's acting chief wastewater engineer explains how important the plant is
11:23it has saved us we are a very dry country
11:28every drop of water count so we cannot afford to let water just run run away because of that we
11:38have
11:39used this to make it drinkable again so that increase our potable source whatever we can we reuse again
11:48we couldn't have survived without it the dams would have run and empty at that stage
11:54in a place where rain is so infrequent whatever does fall needs to be collected and carefully stored
12:02the safest place in vindhook is a huge natural underground reservoir called the vindhook aquifer
12:08the city can store water here until it's needed during extreme droughts it can help keep the city supplied for
12:15almost three years
12:18we've got a lot of sun there's a lot of evaporation and from surface water we get around 50 percent
12:26losses per annum
12:27so if you start with 100 percent at the end of the year you'll sit with around 50 percent
12:32whereas if you put the water on the ground that water stays put while engineers work on large-scale
12:39water solutions local communities are finding simple ways to save water at home community trainer augusta
12:48canconu from the kambashu institute is showing residents in the katatura informal settlement
12:54how to reuse water that would otherwise go down the drain the water is very expensive we are taking the
13:02water from the communal tap so now we train the people to use gray water the water from the washing
13:09the clothes that water we train the people to water on their trees the gray water when we wash our
13:17dishes
13:18because that water is too soapy we train the people to put on the on the pit the pit is
13:26a hole in the middle
13:28of the food sector where we are going to produce where the people are going to produce their own food
13:35for paulus namwandi these simple changes in how to handle water resources have made a real difference
13:42to the health of his garden
13:46it was difficult for us to buy the because there's sometimes there's no money and as we started to grow
13:54our own food we are no more buying vegetable for now easier for us because we can just harvest our
14:03garden and we start eating even though most of namibia is so dry the far northeast zambizi region
14:12is a crucial wetland area other parts of the country also have wetlands that come and go with the seasons
14:19they play a very important role not only in supporting biodiversity and tourism but also in
14:26regulating the region's water cycle britta hackenberg is head of conservation at the namibia nature
14:32foundation she says climate change is making it harder to protect these natural buffers with rainfall
14:38increasingly unpredictable over the last 20 years the samedi region has seen its wettest and its driest
14:44year and i think you know this is exactly those symptoms that we are seeing about climate change
14:49making forecasts more and more difficult to predict and i think this is also where we see you know
14:55shifts in patterns of livelihoods that for example certain crop species don't work in certain areas
15:00because the rainfalls would not allow for that one anymore for namibia drought is not a future threat
15:08it's reality now and that is why wasting water is simply not an option
15:23how much money are you flushing down the toilet every day i'm going to tell you exactly how much
15:28and how to stop it in 45 seconds if you've got this handle type that's 10 liters of water gone
15:33on average for every flush let's say you flush five times daily that's around 50 liters of water
15:39and in a year 18 000 that statuses flat tanks add the expense of electricity you need for pumping
15:45600 nera just for flushing but if a toilet works with these buttons this one flushes urine and releases
15:51less water you only have to use these bigger parts for solid waste that saves 12 000 liters per person
15:57each year and this is a mind-blowing part it's not about the money we can help to protect groundwater
16:02this
16:03week in a dry region like lagos where water stress is already high this is quite a big deal don't
16:08forget
16:08to wash the hands after use
16:12raise your hand if you have ever forgotten to water a plant it is a sad reality that during
16:20summer's tree planting campaigns many saplings do not survive because they're not watered properly and
16:26that is exactly where a group of people in niger comes in because planting trees is one thing but
16:34making sure that they survive and thrive is another
16:44the young environmentalist has invited local volunteers from nigeria's capital nyame to a small
16:49orchard they are here to learn how to help young trees survive
17:08a lot has already been achieved in niger millions of trees are planted every year especially on
17:15independence day in august when it becomes a nationwide effort but two-thirds of these trees
17:21planted don't survive because of neglect and the harsh desert climate the capital nyame also needs
17:29more trees this time people want to get reforestation right volunteer jibo harande tarifatu is doing her
17:37bit more than 4 000 people have already joined the environmental initiative but simply planting trees
17:43isn't enough the saplings need people's commitment and care to survive
17:50if really people can provide support for this and really support the initiative
17:57by helping them to ensure that they follow these trees
18:02so it will be really interesting
18:04yeah suraya explains that removing weeds help young trees survive applying compost helps too but pruning is
18:12especially important it allows the tree to focus its energy on healthy shoots grow more vigorously and
18:19better withstand drought these are the branches superfluous so when they allow them to make the land of the new
18:24grondy
18:25only with me also they'll want to decompose it for uh reparticipate
18:30a lot of information uh to nourish love
18:34those thousand square kilometers of fertile land are lost every year in nature
18:39deforestation is one of the main causes that's why local action matters so much says suraya
18:47it's not too long to arrange the errors of the past a little gesture today for us the ancients but
18:52for the
18:53generations future it will be proud
18:59finally we go to a country where long ago water was abandoned nowadays though almost two-thirds of chad
19:07is arid and people have long adapted to life under such conditions but the climate has changed again
19:14and the rule of water is being examined thanks to some mysterious ancient relics on the spectacular
19:22and nedi plateau
19:25as incredible as it may seem the sahara was not always the arid desert we know today
19:32but the lush green land teeming with wildlife
19:37traced by our ancestors thousands of years ago in northern chad
19:41these ancient paintings testify that the green sahara is no legend certain moments
19:47de l'histoire l'environnement était un peu un peu vert et il y avait des nourritures disponibles pour
19:57les bétails ce sont des animaux qui ont existé et qui sont élevés par des hommes préhistoriques quand
20:06le climat était encore propice à l'élevage de ces espèces animales et plus tard quand le climat
20:14peut-être va un peu changer devenir un peu aride l'homme avait changé ces ces ces animaux ils ont
20:22introduit
20:23maintenant des dromadaires mohammad ahmatoumar is a young tchadian scientist trying to piece that world back
20:29together through rock art and fossil remains found on site si on prend l'exemple peut-être d'hippopotamus
20:38ou des animaux vraiment aquatiques là on imagine que cet espace là serait en quelque sorte caractérisé
20:46aussi par des lacs ou bien des fleuves voilà un peu partout this vanished landscape that existed between
20:55five thousand and eleven thousand years ago is well known to scientists such as paleoclimatologist
21:02florence sylvestre dans cette période de l'ocène on était dans une configuration orbitale qui a favorisé
21:10considérablement l'insolation d'été à savoir notre planète qui était plus proche du soleil pendant
21:17l'été et qui offrait la plus grande façade de l'hémisphère nord vers le soleil donc on avait un
21:22échauffement beaucoup plus important des masses continentales une évaporation océanique beaucoup
21:27plus importante tout était favorable pour avoir une grande quantité d'eau dans cette zone du sahara
21:36aujourd'hui du sahara que l'on connaît aujourd'hui across the millennia the sahara withered into the
21:42world's largest hot desert wildlife disappeared and human communities had no choice but to migrate
21:49or adapt to survive these lessons resonate strongly with communities such as the people from archie
21:59who are already feeling the impact of climate change reshaping the sahara once again climatologist
22:06prédicte rainfall in the region could rise by 30 percent by 2050
22:11cette tarde-là en plus on va qu'elle a du tout sur la force et la question là en
22:18plus
22:19tout à la planète en plus c'est que tu n'as pas à l'insolation il n'y a
22:26qu'un des
22:41The increased rainfall is not only a mixed blessing for the region's inhabitants, it
22:48could be also an existential threat to the prehistoric artworks of Ennedi.
22:55Fortunately, the latest rains spared the paintings.
22:58The danger to which we face now is mainly linked to actions that are made by the man.
23:08And especially, the men use the grottes to stock their goods.
23:13There are some who make graffiti, griffon on the paintings, and by ignorance.
23:22So for the moment, these are these factors that are really worried about us.
23:29Arche is one of the most famous tourist sites in Ennedi, and also one of the most exposed
23:36to human damage.
23:38We have graffiti here.
23:43This is really a factor of the anthropic destruction of painting.
23:49People don't really know the importance of this heritage.
24:06And that's the reason why Muhammad regularly visits villages, to speak with locals, raise
24:12awareness, and encourage them to protect this legacy.
24:16We can't remove the rain sites that we have in the natural and cultural reserve of Ennedi.
24:24So the strategy that we have chosen is to make sense of the local community, to make them
24:31first understand the importance of their heritage.
24:35Because this heritage is also their good, the good of humanity.
24:41And it's really important to protect them.
24:45Muhammad has assembled an archeological team to precisely date the paintings.
24:51This mission, financed by NGO African Parks, is another crucial step to safeguard this heritage
24:57heritage, and share it with the world.
24:59So for me, it's really a feeling of pride, of emotion, and of responsibility for
25:08joining this team and this team, with the hope of finding indices that can really
25:14illuminate us on the river.
25:16The results of this research, Muhammad Ahmad Omar hopes, will raise awareness of how our ancestors
25:23adapted to climate change, and what lessons we can draw for the future.
25:29You can find more stories about this amazing world and our place in it by subscribing to the
25:35ECO newsletter.
25:37Thanks for watching.
25:38And don't forget, you can always share your own experiences of nature and your environment.
25:44Just write to us at eco at dw.com.
25:47Goodbye for now.
25:59Okay, okay.
26:01Oh, he's here.
26:02It's a ECO Africa.
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