[Hannah LS (OP)]

Jenna asks:

For a school project I have to design a city 100 years in the future. For part of the project we have to figure out how to design the city so that it will withstand a natural disaster. For this I was thinking we could do a dome around the city. I was wondering if you could help me see if this is possible?

What do you think?

[syhprum]

The first city that springs to mind is New Orleans efforts are continually to preserve it from flooding generally I think the effort is misguided once a city is found to be in danger it must be abandoned protective measures never work in the long run.     

[alancalverd]

The "protective measures" around New Orleans actually consisted, until recently, of constraining rivers with levees so that swampland could be drained for housing development. The result, of course, has been that hurricanes flood the rivers and destroy the city instead of the rain being distributed over the swamp and absorbed by vegetation.

Not sure of the purpose of a dome over a city. All buildings already have a roof to keep the rain off, and should be constructed to withstand the strongest forecast wind or earthquake for the area. Adequate storm water drainage seems to be the key to survival, plus attention to the surrounding countryside to prevent flash flooding.

Ice storms have caused long-lasting electrical blackouts, but again the problem and solution lies outside the city: most cabling in metropolitan areas is underground, but the intercity grid tends to be on pylons, so for resilience you either need to bury superconducting trunk cables or build fossil-fuelled or nuclear power stations inside the city.

I guess fire is a natural disaster. Lesson from London in 1666: don't build wooden houses close to each other. Lesson from London 2017: think about whatever else you use, and don't build tower blocks like chimneys.


A city is inherently nonsustainable - almost by definition. You need about 0.25 acre of good English farmland to provide the food and water for one person. London has 10 times the sustainable population density, and cities like Las Vegas, surrounded by desert, have no hope whatever of independent existence even without a natural disaster.

[syhprum]

Some cities in really hot places like Dubai or Kuwait already have large areas covered by domes to keep the temperature down to reasonable levels but this is only possible were there is an abundance of wealth to maintain them and slaves to build them.

[alancalverd]

Ancient mediterranean cities have tall buildings with narrow streets, which serves the same purpose. Shop awnings keep the midday sun off the sidewalk, and most of the day the roadway is in shadow. With a bit of cunning you can design the layout like a termite mound (and they got there a million years earlier) so that there is a flow of convective air through the system.

That said, there is little point in designing cities for the future. Trade and manufacturing no longer require proximity and even retail trade is disappearing from brick and mortar buildings. Future generations will build what they want, and curse what we have prescribed for them.

[yor_on]

Generally speaking there are two ways I know of to build a city to withstand a natural disaster.

Build it so that it can withstand structurally which should be very expensive. The other is what old Japan did, easy cheap materials as bamboo that are easily rebuilt after a disaster. To that you can add some shelters specially built to protect people from the worst impact. It's a choice of what one can afford, I would go for the second myself. Then again, my wallet aint that thick.