Can a 1930s-built city have a population of 5 million by the 21st century

[Nightingale]

Good day. In my TL, "Onward March of Freedom", I had President Roosevelt in my TL's late-1937 expand the Resettlement Administration to build new Tennessee Valley Authority duplicates in other states...

And most of all, build new cities in each state to facilitate recovery from the Great Depression. Some states, such as in the Midwest, California and Northeast, get more cities owing to geography, land sizes, better Civil Rights records, most especially New York, California, Pennsylvania, Ohio, New Jersey, Illinois.

With that, may I ask, is it possible for any of those planned cities, barring any major disaster in the US or in any other country, have a population of around five million by 2018? I wanna settle this so that my TL can be as realistic as possible. Thanks!

 

[CV12Hornet]

Good day. In my TL, "Onward March of Freedom", I had President Roosevelt in my TL's late-1937 expand the Resettlement Administration to build new Tennessee Valley Authority duplicates in other states...

And most of all, build new cities in each state to facilitate recovery from the Great Depression. Some states, such as in the Midwest, California and Northeast, get more cities owing to geography, land sizes, better Civil Rights records, most especially New York, California, Pennsylvania, Ohio, New Jersey, Illinois.

With that, may I ask, is it possible for any of those planned cities, barring any major disaster in the US or in any other country, have a population of around five million by 2018? I wanna settle this so that my TL can be as realistic as possible. Thanks!

Probably not, if you’re building them in every state. That kind of rapid urban growth requires lots of migration from the countryside and other cities, and this will dilute that migration by spreading it out.

Compounding the problem is that only one city in the US today has that many people (discounting metro areas): New York. Even Los Angeles doesn’t even crack 4 million.

 

[Deleted member 6086]

Phoenix, AZ comes to mind, as though it wasn't founded in the '30s, it had a tiny population then. Also the Las Vegas area, though neither met area has a population of 5 million, to my knowledge.

 

[Pkmatrix]

With that, may I ask, is it possible for any of those planned cities, barring any major disaster in the US or in any other country, have a population of around five million by 2018? I wanna settle this so that my TL can be as realistic as possible. Thanks!

Absolutely. It's not the U.S., but consider the example of Brasilia in Brazil which was founded in only 1960 and had a population of 2 Million by 2000. Brasilia's growth has slowed (it's only around 2.4 Million now), but it doesn't seem impossible for your planned city to have around 2 Million by the 1970s and over 4 Million by 2018. You'll just need to find a way to justify the continued steady growth over those 80+ years.

 

[BootOnFace]

Phoenix had 50,000 people in 1930 and the metro has almost 5 million today. It's possible, but you would have to really warp things around it.

 

[Bytor]

If you had 1,000 people settle in such a city initially, that would be about 11% growth per annum (1,000×1.11⁸³=5,778,395), or 280% per decade (1,000×2.80^⁸·³=5,145,311). If you've wikipediaed city demographics as often as I have you'll have seen many examples of 20% to 40% per decade, but not 280%. So it would seem ASB to me.

 

[General Tirpitz]

Does Shenzen count as a non-US example of this? It had 30.000 people in 1980 and, depending on the definition, has now 10-20 million people, mostly due to its status as a Special Economic Zone and location next to Hongkong. Although not planned like Brasilia, which Pkmatrix mentioned, it does have a special status when compared to regular Chinese cities.

 

[Pkmatrix]

If you had 1,000 people settle in such a city initially, that would be about 11% growth per annum (1,000×1.11⁸³=5,778,395), or 280% per decade (1,000×2.80^⁸·³=5,145,311). If you've wikipediaed city demographics as often as I have you'll have seen many examples of 20% to 40% per decade, but not 280%. So it would seem ASB to me.

It's not ASB (no magic required here) and there are real world examples we can point to. If OP wants to go into that level of detail they'll need to take the time to explain what's driving the sustained growth over 80 years, but saying "ASB" is absolutely uncalled for here.

 

[Wimble Toot]

Only if it's in China.

 

[Bytor]

It's not ASB (no magic required here) and there are real world examples we can point to.

What real world examples of 280% growth over a decade can you point to? The fastest growing cities today like Suzhou in China are growing at 5% to 6% per year for abut 70% over a decade, but the OP wants 4 times that maintained for 8 decades. You know the depopulation of Detroit since the 1950s high of about 1.8M people? This scenario, if it is relying only in migration internal to the USA, would need 3 or 4 Detroits per each New Resettlement City.

If every single immigrant to the USA were forced to live in the new cities and definitely stay there (but let their American-born children move away), it could be done. There was about 35-40 million immigrants to the USA since 1930 which would allow for 7 of these new resettlement cities to happen. Even with a mixture if internal migration and immigrants, the OP still needs to depopulate much of the East Coast to make this scenario happen.

 

[CV12Hornet]

What real world examples of 280% growth over a decade can you point to? The fastest growing cities today like Suzhou in China are growing at 5% to 6% per year for abut 70% over a decade, but the OP wants 4 times that maintained for 8 decades. You know the depopulation of Detroit since the 1950s high of about 1.8M people? This scenario, if it is relying only in migration internal to the USA, would need 3 or 4 Detroits per each New Resettlement City.

If every single immigrant to the USA were forced to live in the new cities and definitely stay there (but let their American-born children move away), it could be done. There was about 35-40 million immigrants to the USA since 1930 which would allow for 7 of these new resettlement cities to happen. Even with a mixture if internal migration and immigrants, the OP still needs to depopulate much of the East Coast to make this scenario happen.

Well, we could also change the starting population. 1000 seems a bit small.

 

[Bytor]

Well, we could also change the starting population. 1000 seems a bit small.

Even 10,000 initial settlers in the first year would still need 215% growth per decade, (10,000×2.15⁸·³=5,744,327) or 7.8% per annum (10,000×1.078⁸³=5,097,499). That's still beyond anything we see OTL. Even the fastest growing cities in China like Beihai or Suzhou are only in the 3% to 4% range, IIRC, and the OP needs 80+ years of this sustained incredible growth.

With a million people to start off you could do it in 83 years at 2% growth per annum 1(,000,000*1.02⁸³=5,173,855) or 22% growth per decade (1,000,000*1.22^⁸·³=5,209,386). But even today only 2 of the top 25 fastest growing cities in the USA have a growth rate of over 2%, and getting a 1,000,000 to move to a newly constructed city in the space of a single year so from then on you can use real-world high growth rate (yes, 2% is considered a high growth rate in North America) is even more implausible than 5,000,000 in 83 years.

 

[Nightingale]

How about one

Absolutely. It's not the U.S., but consider the example of Brasilia in Brazil which was founded in only 1960 and had a population of 2 Million by 2000. Brasilia's growth has slowed (it's only around 2.4 Million now), but it doesn't seem impossible for your planned city to have around 2 Million by the 1970s and over 4 Million by 2018. You'll just need to find a way to justify the continued steady growth over those 80+ years.

How about like providing regional urban opportunities for rurals (especially Blacks and other minorities) migrating to the cities?

And then if we had a higher US birth rate...

 

[Wimble Toot]

It's not the U.S., but consider the example of Brasilia in Brazil which was founded in only 1960 and has a population of 2 Million

Yes, but this North America town/city won't be the capital of the USA, whereas Brasilia is the capital of Brasil.

The factors that apply to the expansion of Brasilia won't apply to a North American city

 

[RyuDrago]

In Africa there aren't particular cases of booming cities during the 20th century?

 

[Arkenfolm]

In Africa there aren't particular cases of booming cities during the 20th century?

Most major cities in sub-Saharan Africa would fall into that category, but most were founded in their modern forms in the late 19th century, often on the site of a local village.

The best example might be Abuja in Nigeria, which was founded in the post-colonial era. The large growth is due to the fact that it's a planned capital, same reason as Brasilia. Given a few decades, Abuja will probably surpass 5 million people. Similar examples like that could exist elsewhere in larger African countries or elsewhere in the developing world. Naypyidaw, current capital of Burma, might also count given a few decades, and it was founded in 2005.