The Boring Company FAQ

OTOH JR Central is in the process of building a tunnel from Tokyo to Nagoya: https://en.wikipedia.org/wiki/Chūō_Shinkansen

That's like comparing oranges to apples. And planes, indeed fly over your head all the time; there is probably hundred of thousands of them in the air as we speak - how many of them are falling on your head?

If I have a choice of an autonomous emergency parachutte -deployed landing done by my mid-air broken aircar, and being stuck in the heart of Earth with no air and very high temperature literally feeling like a needle in someone's body, I chose the falling cars.

Part of me keeps waiting for someone with the right clout and means to attack the elephant in the room:

Change the rules of the road.

Our roads can move far more cars per unit time than they do now. This is easy to see if you drive around Los Angeles for a fair amount of time. I drive the 405 corridor with some frequency and I can say it has gotten worst over the last few years.

Yet, the one common theme you see every day consists of these characteristics:

  - Cars driving everywhere at whatever speed they want
  - Cars driving slowly on the left
  - "Synchronized" driving, where two cars drive equally slow side-by-side
  - People who can and want to drive faster have to zig-zag through traffic
  - The carpool lane is inhabited by people who do nor carpool
    Just because a car has more than one person it doesn't mean they are
    carpooling.
  - The carpool lane has buses going slow and sometimes (often) empty
  - No penalty for slowing down when going uphill and causing backup

It's insane, there are no penalties for going slow and causing backups that trigger massive oscillations that lead to the entire freeway going through these nodes where speed grinds down to zero. This wave travels backwards and it can be triggered by slow or insecure drivers. I've seen in time and time again.

If I were to generalize, the rules of the road are not designed or evolved to optimize flow. You can't even say they are optimized for safety because there is nothing safe about a moron going 55 on the fast lane while people are swerving all over the place to get around him.

What we need is a new mentality: Caltrans and CHP need to work together to optimize flow, not get in the way of it. The carpool lane is a disgrace. It takes-up 20 to 25 percent of the road's capacity for no gains whatsoever. We need a layered system where slow drivers get out of the way and don't impede others. I am not saying go full autobahn but there's merit to the idea that slow drivers should not be allowed to impede others. I've watched the 405 grind to a halt because of a few (two or three) drivers who manage to lock-up an area. It always gets worst before it gets better.

Tunnels? Sure. But first fix the real problem.

This is where self driving cars might do an amazing job. We will be able to extract far more capacity out of the existing infrastructure by increasing speeds and layering them from right to left.

I'd like to know more about this. Check valves [1] do just this, and they work without energy input, what is the difference ?

https://en.wikipedia.org/wiki/Check_valve

Well, given that both tunnels and elevated roads are still being built, the most expensive likely varies depending on the situation. If Musk really reduces the cost of tunneling by 10x, that calculus will shift in the direction of tunneling, obviously.

Dirt roads are extremely cheap and have been around forever. That doesn't make them the best choice in a modern society.