Nuclear war escalates throughout the world, quickly enough to kill much of the world population, but slowly enough to allow groups to find shelter (say a period of a month). The fallout leaves much of the world uninhabitable and as a result, two main groups arise: those living far underground, and those living at sea.

There already exists a number of underground nuclear shelters, ranging from small backyard shelters to excavated mountains occupied by the US military[1]. This group, however, would be far larger, almost city sized, and occupy a similar amount of land. They would be able to access the outside world for very brief periods, but would not be able to travel far. All food would have to be created inside, water would have to be purified and come from local sources, and energy would have to be at least partially renewable (looking at a period of a year or two, with thousands of people). Underground cities have existed, and still exist all over the world[2], but this one would be different given its isolation and need for sustainability. Previously existing supplies of fuel, water, and food may exist, but would eventually run out. The ocean bearing survivors would consist of a convey of boats and large ships (potentially cargo or cruise ships) fastened together to some degree in the Pacific Ocean. It would be far enough out to avoid major fallout and it would be able to move locations to avoid storms or find better food sources. People could come and go, but most would stay with the fleet for the protection and resources that it brings. This group could also incorporate things like submarines or oil platforms.

Major issues would be related to resources such as food, water, energy, and ability to remain safe from the fallout. Considering these two situations and the challenges they face, which group would have a better chance of surviving? Which group could maintain a better quality of life?

[1]https://en.wikipedia.org/wiki/Cheyenne_Mountain#NORAD_operations_center [2]https://en.wikipedia.org/wiki/Underground_City_(Beijing)


3 Answers 3


The major difficulty facing survivors in an underground city is they are literally stuck there, and can only easily access the supplies and stores that have been stockpiled within. Unless they have thoughtfully built their city inside a coal mine, it is going to be virtually impossible to extend their survival by mining, mostly because the vast majority of elements extracted from a mine need to be heavily processed in order to become a useable product (iron ore to steel, for example, is a very energy and resource intensive process, and even more so to make the various alloy steels modern civilization needs).

So a city sized construct is going to need massive warehouses of goods and food, most likely a nuclear power plant to keep the lights on and a very elaborate system to recycle wastes and reprocess air, or some very secure way of disposing of wastes. An underground city is also vulnerable to being flooded, and if the pumps fail could quickly become an underwater city instead. In fact, you could make the case a large city sized construct would be needed to secure the survival of a small town underground, especially if they need to be sealed from the outside environment for several years.

The Sea Steaders, on the other hand, have mobility, access to sunlight and water, and with some careful planning, can keep their exposure to fallout to a minimum. The great air masses between the Northern and Southern hemispheres do not mix to a large degree, so, unlike "On the Beach", people in the Southern Hemisphere are unlikely to be poisoned by fallout from the war in the Northern hemisphere. Right on the equator, they can take advantage of the doldrums, and essentially be in a dead air pocket without a lot of fallout reaching them.

At sea, they can also access raw materials more easily than the people trapped underground. If they were well prepared they could fish, dredge for materials on the sea floor, generate solar energy and distill fresh water, grow crops in sunlight and live a relatively good life. Their biggest advantage is that they are on the surface, so will be the first to observe any changes that could enhance their survival. They can also move towards wherever has the best prospects to renew civilization, unlike the cave dwellers, who will be more or less limited to the area around their underground city once they reach the surface (If the ground has been devastated by nuclear strikes and then several years of weathering, roads and other transportation infrastructure will be mostly unusable, and require heavy construction equipment to repair).

So overall, I think the Sea Stead will be the better place to survive the prolonged effects of a post apocalyptic environment.


This questions hard to answer but I'll try my best. First Underground

Pros: no chance of being exposed to radiation. You cannot be affected by the elements ( except for perhaps an earthquake)

Cons: must retain self renewable resource system. Single accident like the destruction of a Greenhouse or the destruction air filtration system could result in a catastrophe.

Second floating city at sea

Pro: less dependent on equipment. If your crops fail or water filtration system malfunctions . Your city may still survive by harvesting Rainwater or living off fish.

Con: you are more exposed both to the elements and to radiation as well as other possible hostile survivors ( is quite possible that at least one of the floating cities might resort to piracy. )

Conclusion: underground cities have short-term security ( protection from the elements and radiation) but long-term risk ( very vulnerable to equipment malfunction). Floating cities are the opposite. With short-term risk of storms piracy and floating too close to radiation zones but less vulnerable in the long term because they are less dependent on equipment.

All in all if you're a first generation Survivor of a nuclear apocalypse having to choose between a floating city and underground city based purely on Survival alone choose the underground city while there might be problems in the long term you'll probably be dead before the equipment begins malfunction.

Of course that's from the standpoint of an individual lf you want me to choose which is best for the survival of the human race then I would have to choose the floating cities. No matter how good the equipment that something's going to break down eventually. Since the floating cities are less vulnerable to equipment failure we have more chance of surviving long enough to repopulate the Earth once it's no longer full of radiation.


my bet wil be the land-base (Group A) one, mostly because i can not see any chance to survive for the sea-base (B). However, both group can move to the wilderness, or some island that remain intact like Fuji or Togo, and their survive rate will be much better than original. But if they have to stay in these lifestyle no matter what, then:

  1. food: A 1-0 B
    simply put, A can grow their food. and while eating somewhat radiant food is not very healthy, it not like you will die instantly from that. For examples, there still a few people who live in Chernobyl by farming; and this area is pretty much a normal wildland by now (30 yrs after), with normal-looking wild boar and deer and such.
    meanwhile, B can not grow their food, and have to rely on fishing (if they choose not to colonize islands). that mean they don't have much vegetable in their diet, which may lead to scurvy and such. but what more important is that their fishing is not sustainable, because of energy.
  2. energy: A 1-0 B
    to fishing, you need boat; and to run a boat, you need fuel. and you can not produce fuel by yourselve. sure, you can make sail, but these sailing ship will be pretty much makeshift and not very effective; not to mention our modern sailor don't know how to operate a sailing one. Even if they do, you still have to move your fleet (or city) around, because you already exhaust the fish population in that area. And when your fuel run out, the city will become an isolate and uncontrollable floating prison.
    meanwhile, A don't really need energy or fuel. for much of history, human have been able to survive and grow without these thing. and if they can find some solar panels, that great.
  3. water: A 1-0 B
    A have more available water source than B, even though "clean" water will be hard to find for both group. the ship's desalinator (if they have one) is not mean to serve a population that large. you could try boiling the seawater and collect the steam, but they don't have much mineral and not mean to drink daily.
  4. safety: tied
    storm, shipwreak, lost in the middle of the ocean is compensation for raid or any dangers group A have to face.

so in short, unless the Sea people have somewhere to land and colonize, their chance of survive is really low; and for that reason it's better to stay on the land instead.

  • 2
    $\begingroup$ @ThoGia I see no reason why the floating cities cannot grow their own food. $\endgroup$ Jun 25, 2016 at 13:49
  • $\begingroup$ @ Bryan McClure: you can only use the deck to grow food, because it the only place to have enough light. but then your field wil be vunerable to the enviroment: strong wind will carry away the soil, and salt water from high wave is not good for plant either. lack of water and space is other problems as well. $\endgroup$
    – Thỏ Già
    Jun 25, 2016 at 14:42
  • $\begingroup$ @ThỏGià Greenhouses are definitely a possibility, as well as using solar energy to purify water. Water desalination takes a whole lot of energy (as we are learning in California), but a few barges with solar panels could have this be their sole job. Water recycling facilities would also be useful. $\endgroup$
    – matt_Vera
    Jun 25, 2016 at 15:15
  • $\begingroup$ @ matt_Vera: both solar panel and water recycling facilities need lots of maintain, and i don't think this town have the material and specialized engineer for that (not to mention the input for the water recycling like chemistries or such). Beside, to scavenge the water recycling facilities, move it to the shipyard, and then modify the ship to fit that thing is quite a task for your survivor. $\endgroup$
    – Thỏ Già
    Jun 25, 2016 at 16:15
  • $\begingroup$ @Tho Gia couldn't a sun house set up in a floating city provide at least some protection against the elements? $\endgroup$ Jun 25, 2016 at 20:12

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .