announunr: opportunity. prospetyty. optimism.. nile. for many ethiopians, the river's water is sacred. and soon, it'll provide power to the country, too. which is what many egyptians, further downstream, are afraid of. the nile is the country's lifeline. but first, we head to china, where e migrant workers are beg ousted from cities en masse.

where will they go? migrant workers make up a third of china's labor force. they are peoplple who leave thr villages and head to the metropolises in the hope of finding a decent job. for years they were absorbed into city life -- after all, they were a key factor in china's economic miracle. but many are still treated as third class citizens, and aren't even officially registered. it's estimated that there are 282 million migrant workers across china. beijing's population alone has trebled over the past 25 years. authorities say it's too much. they want millions of the migrant workers to leave. reporter: ththese migrant works have been evictefrfrom the homes in xinjian village oththe ououtskis of b beijing. ththey have to b be out by da. mrmr. liu has toto find shelter himself and his workers. heamame toeijing 23 years ago,

aneventual becamthe owner of a smallextitileworkshop nonow they have e to pack evereg into a truruck a leaveve. tomorrow, the builngng coulde demolilish. liu: two weeeeks ago therere wa fire h here in one o of the buildingngs. the next day o officials camamd told us we had three days to leave. i s said, tee d day ththat's impossisible. we've t nono idea where e to g. repoporter: gas, e electricityd wawater re shuhut f straigig away, despite freeng temperaturesutsiside. officially t they say thee buildingngs have to bebe vacater fire safety reasons, but t resints s suspect somemething me sinisterer -- that beieijing ws to getet rid of its s so-called low-end d population.. daylight reveals where it all began. the fire broke out in this building. 19 people died. after that, the governntnt hailily drew up a a 40-daylan to

evacuate all the illegal and unsafe buildings and structures in beijing. many believe it's a plan to drive the 10,000 affected out of the city. wang gangqiang comes from the impoverished province of gansu and works in beijing ironing textiles. wang: we have to be out by this evening. and i really don't know where to go. reporter: a feeling of hopelessness permeates the entire workforce of the factory. many people have been here for decades doing work that people from beijing wouldn't do. they have no rights because no one has a beijing residence permit. now they have just hours to pack their things. zhao: it's not fair. they should have given us more time, at least. niu: i came e here in search oa better life,e, far from my h h. i was very ambitious.

now i just feel sad. i have no other choice -- i have to go. reporter: on the outskirts of beijing, xinjian village is being demolished. all that's left is debris and rubble. the old town has been disappeaearing for monthths. ththere's nothining left for e migrant t workers who o buit themlveses a le herere. it's caused an uproar among the beijing population. but t the photos a and vides uploadaded by bloggegers quicy disappear from the interernet - ceored b by e state.e. one group uses an online map to show where the evictions are taking place across beijing. they call it a map of fire protection measures as a way to avoid censorshsh. support groupsps have also sprg up, like here in west beijing. an artist group wants to turn their cellars into accommodation

for the migrant workers, to give a bed and shelter to these people who give so much to the city. liu: the workers have established small convenience stores in our neighborhood, like the fruit vendor and the little shopop on the corner. they make our lilives more comfortable. reporter: these offers of support are being closely monitored by the government, because they're afraid that criticism m could lead to protests. this small village lies in hebei, the neighboring province of beijing. migrant worker liu andndis employees are stayinhehere teteorarily, but they're n not really welcomeme. in the village, there areveven

official announcements warning not to rent to textile companies because e of the fire e ris. >> f for the 2008 8 olympic ga, beijing g said everyryone ws welclcome, even usus. nonowe've justst been discarar, it's so crcruel. repoporter: since e the eviction beijing, liu has only secured himself a temporary refuge. the next step is still unclear. liu: we made a life in beijing as migrant workers, because we had no better option. now we just get thrown out wherever we are. there's nowhere for us to go. reporter: no space among the 22 million residents in beijing. in 2016, the government initiated plans to make cities cleaner and d more livablel. bebeijing set a target to redue the population by nearly two million people -- starting with the most v vulnerable. host: and it's the most vulnerable who generally lack

access to clean water, too -- as many as 2.1 billion people worldwide. around 263 million people have to walk at least 30 minutes every day just to access water at all. and 159 million get their water straight from lakes and rivers. the world's longest rivers, in fact, ensure the livelihood and survival of billions of people. rivers like the nile. for many in egypt, it's their only source of water. reporter: ahmed abdel hadi has been rowing on the nile for as long as he can remember. when he's on the river, the commotion of cairo seems far away. close to 23 million people live in greater cairo. egypt's capital is expanding, and so is its population -- by around two million people a year.

almost the entire population of egypt lives close to the nile -- and drinks from it, too. the river is egypt's lifeline. ahmed: it's the center line in my life, i think in all egyptian's lives. without the river nile, egypt is just a desert. just a desert. that's it. for me, without the river nile, my life would be just a desert. reporter: egypt is mainly made up of barren wasteland -- sand and stones. the nile provides 95% of the country's water supply. fields are irrigated with water from the nile.

ahmed, the rower, is an agricultural consultant. farmers share their worries with him. mohammed: if the water go down, egypt will be a desert. an old civilization, like old ancient egypt, the nile valley. if this goes down, it would be a catastrophe. reporter: many fear that this is exactly what could happen when the grand ethiopian dam upriver is completed. egypt would not have as much water for irrigation. ahmed: if you stop irrigating, the salty water will get up, and you will be affected for many years. if you keep growing the land, you won't have any problem. but if you stop, if you have no water for some timime, you wil have a problem, and the problem will stay with you.

reporter: here in the nile delta, there are wide canals, and water seems plentiful. this is a fertile area, but people don't appreciate how valuable natural resources are. rubbish floats on the water. although egypt is already dealing with water shortages, farmers often use an ancient irrigation method -- they completely flood their fields. hassan el sayed cranks up his water pump. experts say this old-fashioned method of irrigation wastes much too much water. the solution would be that farmers like hassan should learn how to save water. water shortages in the summer months are nothing new. hassan, however, blames it all

on the ethiopian dam. hassan: the dam is already having an impact.. this canal always used to be full and i didn't need a pump. there's clearly less water now. reporter: kirsten nyman is from the giz. the german development agency is providing support to a farm school in the nile delta. these farmers don't just need to save water, but must learn to grow more food with less of it. egypt's population is growing dramatically -- there are two million more mouths to feed every year. even small changes can have major consequences. kirsten: any drop in water levels will have an impact, whether it's because of the dam, population growth, or climate change. it will affect the soil, and farmers will have to learn to deal with that in order to secure their future. reporter: as soon as ethiopia

starts filling its new giant reservoir, there will be less water for egypt. according to ahmed, the agricultural consultant, no one is quite sure how much less or for how long. but one thing is certain -- there will be less, not more water. at the moment, egypt imports around 60% of its food stuffs. but the country can't really afford any more expensive imports. >> i think we need to get more of everything. more housing, more food, more water. not less water. so, less water with the same equation would be catastrophic. reporter: when ahmed is rowing on the nile, he's removed from the commotion and the hubbub of cairo. but as soon as he's back, he's confronted with the fact that the nile -- egypt's life-line for all of history -- may soon

dwindle to a shadow of its former self. host: and this mighty river is not just a lifeline for egypt, either. the white nile and blue nile join in sudan, and the nile continues its journey northwards towards the mediterranean. today, this waterway provides around 300 m million peoplplen five different countries with water. but by 2030, the region's population is forecast to reach 396 million. wiwill the nile still be able mt all their water needs? especially given that africa's largest dam is currently being built in ethiopia. reporter: beyond this simple string barrier lies one of the most sacred locations in ethiopia. only orthodox christian males, who are fasting and barefoot, are allowed papa. the e legendary source of the be nile, or gish abay as it's called here, is off-limits for all others. some 100 kilometers downriver,

the precious waters flow into lake tana -- the largest lake in ethiopia. one of the many orthodox monasteries which dot this region is located on a small island in the middle of the lake -- debre maryam. belief in the power of the river's water draws pilgrims to debre maryam as well. priest eshete medhem was born and raised on the banks of the abay river. eshete: abay means life to me. not only because the water is holy, but also because the church on this island gives me work. the church and the river are closely entwined. people come here to be cured. once upon a time the nile's waters even raised some from the

dead. reporter: a river so powerful, people even ascribe miracles to it. 30 kilometers south of lake tana, the blue nile falls are africa's second biggest. the falls are themselves a miracle in ethiopia, a country generally notorious for drought and hunger. time appears to have stood still in the impoverished highlands. further south, the blue nile bends westwards, heading towards the sudanese border, where it will be used to provide the country with electricity. 40 kilometers before the river reaches sudan, a huge dam and hydraulic power station are taking shape on africa's biggest construction site. 10,000 workers toil here day and night. the grand ethiopian renaissance dam was supposed to be completed last year, but it's behind schedule. ethiopia intends using the blue

nile's physical power to end its dependence on international development aid. tenalem: africans can make a difference. africa is a resoururceful continent. africa has all the potential to develop. so that's -- we have to lookok inwards. if we think that way, then we can change our continent. i think it's an eye-opener to the e continent, ianan say. reportrter: atver r 1800 squae kilometers, the dam's reservoir will cover an area three times the size of lake constance. its power station will generate over 6000 megawatts. that will supply all of ethiopia's electricity needs, with some left over for export to generate some income as well. project manager simegnew bekele says the dam is good for the soul of a country that the world underestimates.

we know that we are poor, and we have committed ourselves to come out of this poverty level. reporter: it's an expensive way of tackling poverty, especially without foreign funding. ethiopia's government is financing the mammoth $5 billion dam out of the country's own pockets. quite literally -- because there wasn't enough cash available in the treasury, civil servants' pay was withheld -- ostensibly on a voluntary basis. public donations and lotteries also channeled money into the project's coffers. simegnew: this is a projecect tt willll benefit others equally s it will benefit ethiopia. and we know this is a historic river. we have a strong relationship to the downstream countries. they are our brothers, thehey'e

our sisters. we are constructing this project in a responsible and professional manner. reporter: that may well be, but downstream, sudan and egypt are fearful the dam will restrict the nile's flow. for ethiopians though, the new dam is not only a symbol of national rebirth, it's nhihing shsht of a modern woer of f the world.d. host: and now it's time rr global ideas, when we meet people dedicated to protecting our planet's wildlife. this time we're off to meet some pink dolphins. we joined a very specialal expedition in brazil. for the first time, , scientiss are researching these mammals along with the h habitat.. reporter: gotcha! researchers have just captured an amazon river dolphin mother and her calf in a branch of the

river in brazil's juruena national park. the team says it's all for their own good. everyone's focused. this world wide fund for nature-led expedition is the first to land the animals, which will be given a medical examination and fitted with gps transmitters. marcelo: we know very little about the pink river dphphin species. we know a few things about their distribution, but nothing at all about their numbers, their health, their blood values, parasites,s, or if they have bn exposed to toxins. reporter: the animals are given a thororough check-up. the unprecedented project is a cooperation betwtween vets, mare biologists, fishermen, and conservationists. they have to work fast because the dolphins can only y surviven land for a short time. no pink river dolphin has ever had an ultrasound scan before -- it presents a challenge even for

the vet. and whilst the mother is undergoing tests, her baby has already been weighed and measured. after nearly an hour, it's time to return the animals to their natural element. [applause] miriam: it was a complete success -- the team was exemplary. a few adjustments might have to be made, but it was the first time. and it was a mother and her calf, which makes things more difficult, but they stayed calm. everything worked out perfectly. they've already swum out, but without a transmitter, unfortunately. the next one won't get away.

reporter: the fishermen come from the nearby village of sao manoel da barra. the people here live with and from the riverer -- they're jut as dependent on clean water as the dolphins. with hardly any jobs available in the heart of amazonia, many leave the villages. not everyone can work in the local shop. some try their hand gold prospecting -- often illegally. >> it's how i survive. itit's all i've got -- panning r gold. when the gold mines on land closed down, t things got bad here. there's a bit of tourism, but that's not enough for everyone. the only thing left for r to do is look for goldld. reporter: slag heaps left by mining barges are everywhere,

even right next to a a nature reserve. the barges pump gold-bearing mud and gravel up from the riverbed. it's collected in mats where it is then sifted by hand. the noise is deafening, and there are hardly any safety measures in place. is it dangerous? guido: look at this -- it happened while i was changing the suction pipe on the pump. parts are all heavy, and if you aren't focused on what you're doing, it's easy to have an accident. reporter: even more dangerous, especially for the environment, is the mercury used to extract the gold from the water. it enters the food chain in waste water, eventually reaching humans andnd dolphins.

e wwf tete wants to find out how a affects the a animals. marcelo: we know very ttttle ababout e effefectof mercucu on anim organms. there arfindin about the effects on peoe e -- dage to gans and t cenentr nervous stem -- t we know xt to nothg about s effes on wildnimals. we're concting a t ofof tests in paralle using ultrasnd and bod tests a ll as tiue sampl. we wt t toind out t w the toxifunctions. reporterthe e incrsing number of dams d hyhydrlectric plants aralso a threat to the dodolphins. marcelo: separatation caused y the presce o of power statatio is the main problelem. they posa a barrier to g genetc exchange. a male and a female can't breed if they're kept apart by a dam. repoporter: thisis time the tes determined to attach a gps transmitter to a dolphin.

it can take hours to net one. and then they still often mange to escape. research into river dolphins in colombia and bolivia is also underway, with other countries to follow. the wwf hopes to build a database of dolphin health throughout all of amazonia. most of the animals here are relatively small and lean -- none weighs over 70 kilos. breathing and heart rate are constantly monitored. this examination runs more smoothly. inside half an hour the tests are complete, and a gps transmitter is attacached to te dolphin's dorsal fin, which consists almost entirely of cartilage. miriam: the animals do feel what we're doing to them. but for the invasive interventions, the biopsies and attaching the transmitter, they're given a local anesthetic. reporter: the dolphin will be

released back into the open water as quickly as possible. the wwf hopes the project will help to get the pink river dolphin onto its list of threatened species, to better protect them and their biosphere. back in the water, the erstwhile captive's buddies are there to lcome it home. host: and that's all for today. but we love hearing from you, so do w write to us at global3000@dw.com, or on facebook. bye for now. see you soon. ♪ [captioning performed by the national captioning institute, which is responsible for its caption content and accuracy. visit ncicap.org] announcer: opportunity.

by dhl.

announcer: this is a production of china central television amamerica.a. walter: how do you insnspi teens to volununteer? the numbes aren't good. only a q quarter of americans age 16 and older are making time toto volunteer a at least once a year, so volunteerirism is at a record lw in the united states. that's according to a 2014 u.s. bureau of labor statistics report. this week on "full frame," empowering the next generation of volunteers to make an impact worldwide. i'm mike walter coming to you from the heart of new york's times square. let't's take it "full frame.""