narrator: the challenges facing our world are growing all the time. how do we build stronger economies with equal opportunities for all? how do we build a sustainable world for generations to come? how do we protect our cities and harness the power of technology for our common benefit? using the latest bloomberg research and analysis we will make sense of the problems of tomorrow. inequality, sustainability, artificial intelligence, the gender gap, and the demographic

time bomb. how we manage our megacities. millions every year swell the planet's cities. can be harnessed economic potential of these hubs or are we creating centers of poverty, inequality and violence? ♪ narrator: this is the age of the city. for the first time in human history more people live in urban than rural settlements. the world's urban population is growing by 70 million people each year. 301 cities account for 50% of global gdp. this will rise to 66% by 2025. if we don't get things right in

our cities the consequences for humanity are profound. >> cities are critically important to the global economy and to progress in the global economy. cities can be sources of chaos as well as development. narrator: this makes them so alluring and so vital. they can be dangerous places. but cities are where fortunes can be made. >> one of the primary actors driving urbanization is opportunity. you live on a farm and you are growing crops. you don't have a lot of opportunity. you see a bustling city, your friends are moving there, they are getting jobs and offices, any manufacturing center, there are restaurants, culture, life. this is attractive, something you want to be a part of. everything is relative. greater access to schools,

greater access to employment. narrator: in 1912 of the world's biggest cities were in north america or europe. 100 years later this fell to just 2. most of the biggest cities in the future will be in asia and africa. >> most of the growth will be in china, india and nigeria. those countries alone will account for 37% of the world's population. staggering numbers. lagos, the biggest city in nigeria. it is adding the equivalent of boston every year. the urbanization rate in the

u.s. is over 70%. in china it is 50%. china may have a lot megacities, but they are going to get bigger or there is going to be more of them. that is going to be a trend. a lot of emerging markets are going to experience trends like that in the next 50 years. narrator: this incredible rate of growth makes the challenges of managing a large city more difficult. >> the biggest risks are the same risks that challenge all of us, politically governing, climate change, economic inequality, productivity, education, transportation. those issues that face cities are the same that face everyone except in a much more concentrated way. narrator: one city battling with

these problems is rio de janeiro in brazil. she believes the world's biggest cities are in danger of sinking under a tide of poverty, infrastructure and citizen apathy. unless we do something about it billions will suffer the consequences. >> the kind of urbanization we have today can only go so far. if we do not change the way we design our cities and make cities change with us we will have serious limits. they will be impossible to live in, miserable places to be. if we change that process it could be nonexistent. we can better build them together. ♪

narrator: managing megacities is one of the great challenges facing the world. this is rio de janeiro, brazil.

narrator: managing megacities is one of the great challenges facing the world. this is rio de janeiro, brazil. 12 million people crowded into its metro area. it is beautiful and vibrant. it also has its problems. crime, inequality, poverty. she has worked with united nations on sustainable development goals and using data gathered from cities to raise campaigns and solve issues posed by the rapid growth of the cities. she hopes he can be a model for other rapidly growing cities around the globe. >> we try to bring it to the

21st century in a way that makes sense to people. i was born in this city. my family has a mixed background. my father comes from a neighborhood that was quite dangerous in the 1990's, quite poor, lower middle class. my mom comes from a wealthy background. the city can be amazing but can be very rough and unequal. that is not just a characteristic of this city. it is something we're saying around the world. narrator: rio de janeiro is similar to many emerging cities. others remain impoverished and cut off. bridging this gap will have profound benefits for us all.

>> it will bring you closer together. they have the density in them. they are the places where most innovation will naturally happen. it's hard to innovate when you are always talking to the same people and hearing the same thoughts. cities are the contrary of that. they are natural hubs for innovation, economic growth and are the engines of growth in most countries. narrator: when the growth is rapid and unplanned the results are gridlocked streets, poisoned air and an infrastructure that cannot cope. >> i come from a city that expanded to rapidly for sure. how do you create sidewalks,

schools, mobility systems to cater to a growing population? if that is happening in environments where inequality is paramount, the challenges are even bigger. narrator: in a mega-city one of the biggest challenges can be getting from a to b. >> are mobility systems in general suck. when you have a poor mobility system you preclude entire segments of the city from enjoying the amazingness that cities have. it is hard for them to get around. you also preclude the rich people from getting to know other areas of the city which can be exciting and fulfilling experience in itself. where creating a city in which everyone is aware -- living in their own territory which is

terrible. narrator: at the forefront of these infrastructure problems are the city's poor who can become physically cut off from the economic opportunities living in a city provides. >> it includes rapid expansion of cities, the fact that in the developing world one third of the population is living in slums, something none of us should accept as we grow and think about a plan in which we want to live. narrator: slums are a result of unplanned expansion. an estimated 863 million people live in slums. if the slum dwellers in india were a separate nation they would be the 13th most populous country in the world. slums are not always hopeless places. >> they are not just sitting and waiting for the government to do something for them. they are creating their own environment.

the modes of the infrastructure were built by the city itself. there is a level of do-it-yourself that you see in more poor neighborhoods than neighborhoods because the government wasn't there. narrator: slums must be handled delicately by urban planners. >> what do we do with areas that were developed by communities but lack infrastructure? even if we are assuming goodwill in terms of how we handle them, to provide those areas with quality public services. there are choices that have to be made. which pieces do believe, which pieces do we change? if we don't handle that process in a way that is human and intelligent and aims at protecting the interest of the poorer communities we can end up with massive rates of dislocation and destroying an urban fabric and social fabric that is so vital. >> we have a neighborhood with a tram.

it is beautiful. most trams were destroyed in the early 20th century. the neighbors organized and cap their trams. it was a forgotten neighborhood for a while. in the past 5-6 years it has been gentrifying. the government decided to turn the tram into a tourist attraction. the only reason why the tram still exists is because we organized and cap did hear. they created the value. narrator: she believes cities often ignore creativity. the result is a democratic deficit which erodes faith in the city government and

alienates vulnerable communities. she believes cities must take citizens with them if they are to expand successfully. >> we have not got it right, the process by which we involve citizens. i have not seen one case of a city that has used the collective intelligence of its citizens and distributed power to make it. when we get that right weevils saw a lot of other issues we see. narrator: to harness the power of our cities we need to heal the divisions within them first. >> if we keep building unequal cities, cities are not very good to live in for most of their population. i don't think we can hope to be happy in these urban spaces in the worst-case scenario would be cities that do not have a soul and become less and less attractive to entrepreneurs, for people who want to create, and

become less wealthy. narrator: across the ocean, another giant city is growing. lagos has growing pains that are excruciating. ♪

narrator: more people live in cities than ever before. it many of the world's biggest cities are struggling to cope. lagos is the largest city in the world without a real system. everyone has to travel by road. for workers, his daily commute takes over his life. >> what time did you wake up?

>> like 3:00, 3, 3:30. narrator: in three years the population has nearly doubled from 11 million to 21 million. this staggering expansion is overwhelmed the city's in poverty infrastructure. >> it should take me for-five minutes to get to the office. >> in full rush-hour how long does it take? >> 6, 7 hours in traffic. three hours going, three hours coming back. it is was coming back. coming back is something else. i don't think i want to waste seven hours of my every day time for the rest of my life. narrator: lagos is ranked in the top five least livable cities in the world.

the economy is bigger than kenya. getting to their desks is a daily ordeal for millions of workers. >> when you see your children? >> weekends only. sometimes i see them during the week if they really want to see me. sometimes they miss me that much. >> it must be quite difficult. >> yes, it is. it is that we have to do. for now. narrator: like millions of workers abraham's first acts getting to work in the morning is to take a nap. >> welcome to my office. >> what are you going to do now?

>> i took a nap for 30 minutes. and get ready for work. narrator: 2000 people migrate permanently to lagos every day. expanding the city from the land to the sea. the result is slums like macoco. >> infrastructure has not kept pace with the population growth. basic measures to access clean water, for example, access to electricity are limited.

before you get to issues related to growth and development, they have to sort out basic issues of infrastructure. narrator: 80,000 people live here in building sitting on stilts connected by a complex system of canals. >> successful cities find ways to deliver services to even the most deprived. that is the challenge in the developing world where resources are at a premium. narrator: residents have developed their own infrastructure including freshwater and electricity. this three-story floating school which doubles at a community center is the latest addition to this unique environment.

the school was completed in 2013. it is cheap and easy to build. they hope it will be a template for future buildings. >> it raises interesting questions of government control. it has been long ignored area. the local residents took charge and tried to improve their own lots with schools. the central government also has decided it wants that area for its own development reasons. narrator: if you, there is a way, an alternative vision of how lagos may develop. a grand project of incredible scale. echo atlantic. >> we are in the alignment of the financial district. echo boulevard. this is where the major

financial institutions will establish headquarters and offices. narrator: it is a multibillion-dollar residential and business district built on 10 square kilometers of reclaimed land. it is a new city or it will be soon. backers hope a quarter of a million people will one day live here with 150,000 workers commuting across the water. >> we looked at an area in london, dubai, and the heart of london, heart of paris, heart of new york. the vast majority are wealthy people. i could not afford to live in the heart of london.

but creating the residence for these people, you are also creating job opportunities. the norm in nigeria, if you create residential apartments, he also create orders for the domestic staff working for that family. this is a city development. it is not a settlement. it is a business sanctum. this is the future. the first commercial development of lagos. narrator: david hopes the first residential units will be opened by the end of 2016 with the infrastructure of the whole site in place by 2022. >> projects raise as many questions as they answer. especially from where local residents are aware.

they may be getting the short end of the stick. they do lend themselves to starting from scratch and being able to build structures where there are schools, hospitals, offices, transportation facilities. they give gigantic cities like lagos to create a model and plan to be executed correctly. narrator: the future paths of megacities like lagos remain uncertain. organic growth or large-scale planned developments like echo atlantic. what's clear is that growth could destroy city immense potential. >> here we are in the 21st century, new york is booming and thriving. it is a tremendous place.

you can see with proper planning and a diverse and vibrant population what is possible. >> i hope those little cities will be interconnected in a sense they will have solidarity networks, brazilian feel that works, and citizens will feel like they're cities where they want to be, is the project they want to build and they can move, visit each other, learn from each other. ♪

♪ ashlee: one of the basic truths of the human condition is that people love to float, and there's no better place to float than here at the dead sea in israel, where large mammals can achieve buoyancy. there is a ritual to doing it the right way. you need to cover yourself with mud, lather up, and relax with a good read. sorry about your white shirt,