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In Defense of The Boring Company

I'm going to talk about what the Boring Company is doing and why I think it is not only not a terrible idea, but actively a good idea!

Preamble:

This is a complicated idea with a lot of moving parts, both metaphorically and literally. You will have totally reasonable questions! Hopefully they will be answered by the time I reach the end, but keep reading until you get to the end; in written format I can only answer questions one at a time, and your specific question might take longer to get to.

In addition, this is describing the system that I think Elon Musk is working on. He hasn't announced that this is what he's working on - it's guesswork and theorycrafting by me - but there is some evidence to it.

A summary: Elon Musk is attempting to redesign urban and suburban transportation on a grand scale, so thoroughly that the majority of commuters choose to use this system because it's better. This is not a thing you accomplish by building a few tunnels under Las Vegas. The Loop is a prototype of a prototype of a prototype; the beginnings can be seen there, but claiming his plans are invalid because of Loop's problems is like criticizing the concept of trains based on Locomotion #1's terrible speed.


Elon Musk has a unique goal: to make a fast inexpensive public transportation system.

Uber and Lyft have a similar goal! They want to make a fast public transportation system, and they have succeeded! They don't care about inexpensive, and in fact they can't accomplish inexpensive, because drivers are expensive. They're working on self-driving vehicles, and this will help, but it won't solve the issue because Uber and Lyft need lots of roads, roads take up land, and land is also expensive. Note that land isn't just financially expensive, it's valuable - we only have so many square meters of sunlight surface on this planet, and it's a shame we're using it on transportation. This is opportunity-cost even if we don't normally count it as a cost of roads; it's kinda factored in right now because we don't have an alternative, but we could have an alternative and we should consider land usage as part of cost.

Car manufacturers also have a similar goal! They want to make a fast inexpensive transportation system, and they have succeeded! They've abandoned "public" by requiring people to buy into the system with a large upfront expenditure (specifically, "buying a car".) This allows them to get rid of that whole "pay for a driver" thing - the passenger is the driver. It's not as inexpensive as it could be, though, because cars need lots of roads, thus land, thus expense.

Public transport systems also have a similar goal! They want to make an inexpensive public transportation system, and they have succeeded! But it's not fast. In fact, it cannot be fast. Group transportation is intrinsically slow; putting more people on a vehicle either requires frequent stops which slows down everyone else on board, or it requires stops at junction nodes which implies transfers which also take a lot of time. Short-to-mid-distance buses, trains, and subways cannot match uncongested cars, and you can test this on Google Maps by going to a city of your choice, picking two positions, and twiddling with the "Start At" option until you find the fastest times for cars and the fastest times for public transportation; in almost all cases, cars are significantly faster, and I've never found a case where cars are more than a minute slower.

(Airplanes have the same problem, but they're fast enough that people put up with it; nevertheless, an airplane trip still involves an hour or two of bureaucracy and waiting on either side, and chances are good you're not landing at the exact time you'd prefer to. Long-distance trains also have the same problem and the same solution, specifically, "we put up with it because the speed makes it worth it". In both cases, avoiding all that added complexity would make them significantly better. If you can think of a way to accomplish that without a drastic price increase you will become extremely rich.)

tl;dr: Transportation has traditionally been "fast, inexpensive, public; pick two", and Elon Musk is trying to pick all three at the same time.


The Basic Idea

If you haven't heard of the Boring company or the Las Vegas Loop, here's the concept:

Elon Musk thinks tunnels can be built for much cheaper than they previously could be. He is building a large underground network under Las Vegas, with something like 45 stops (this number keeps increasing as they add more to the plan). You will walk up to a stop, request a car, and travel to any other stop in the network. You can do this today, although right now they only have 3 stops, but construction continues.

This is literally the basis of the plan; "let's make tunnels and drive cars through them". I acknowledge this sounds dumb, but it may actually be the best way to accomplish Fast, Inexpensive, and Public.


Let's tackle the easy ones first.

Boring Company tunnels are public because you don't need to buy in with a large investment to use them. You can just show up at a stop, pay a fare, and ride a vehicle to wherever you want to go.

Boring Company tunnels are fast . . . sort of . . . because it's point-to-point transportation. The vehicle is ideally already at the stop, or close by, when you request it, and it takes you directly to your destination, as long as your destination is on the system. This "on the system" limitation is a flaw! We'll get back to that, though.

Boring Company cars currently require drivers, which is expensive. They've said multiple times that this is a stopgap until they have self-driving working. I see no reason to doubt them and the rest of this post is going to take on faith that they'll get self-driving working. Again, prototype of a prototype of a prototype. If you're skeptical about self-driving in general, note that as of this writing there are multiple companies running public services in multiple cities; if you're skeptical about Tesla self-driving, well, me too, but they can always license it. I'm going to just accept this part as solved-in-the-next-decade-one-way-or-another.

Boring Company tunnels are inexpensive because oh god this is where the complicated part starts


Price

Tunnels are, traditionally, very expensive.

There's a lot of reasons for this. Cost disease, in general, is one of the big ones, and if Boring Company gets hit by cost disease then this entire thing might be doomed. I think they're more resistant to this because they are not having cities come to them asking for services, they are going to cities to propose services, and if they're expensive, they won't get any contracts. Note that Boring Company has already turned down a contract because the company was going to waste a lot of money on things that weren't the tunnel, and they just didn't want to be a part of that. I'm going to just cross my fingers that this doesn't happen.

Tunnel size is another big one. Tunnels get much more expensive as they get larger. Train tunnels need to be surprisingly large; they need to hold a train that's big enough for people to stand up in and walk around in. They also need to hold some kind of emergency exit system. With trains, this traditionally hasn't been compatible with the train rails themselves; the cross-ties are a tripping hazard. If you have to run a second extra walkway next to your train then that makes your tunnels even larger. Finally, you need a lot of emergency equipment. The reason this is required is that stations are rather far apart; if stations were closer, the safety regulations let you basically say "look, there's an exit right there, just walk to the exit". Far-apart stations cause significant added tunnel expenses.

The biggest issue, surprisingly, is the underground stations. The most common way of making an underground station is as simple as it is costly:

  • Knock down all the buildings above the station

  • Dig a giant rectangular hole

  • Reinforce the top of the hole

  • Fill the top of the hole back in

  • Build new buildings on top

This isn't a lack of foresight on the part of the builders, this is actually how it tends to be done. Underground stations are horribly expensive, and this has consequences for the rest of the system. Remember how I kind of skimmed past "far-apart stations cause significant tunnel expenses"? Well, they do, but this is still cheaper than building more underground stations!

This is how the Boring Company is going to solve tunnel price:

  • Cars are much smaller than trains [citation needed] and don't require as much sheer size.

  • Cars travel on concrete, not rail, and this surface is perfectly suited for passenger exit, meaning that you don't need an extra passenger lane as long as there's enough room to get past the cars. (Note: in the current Loop tunnels, there is, even though it's not obvious in a lot of the videos that have been posted. It's not comfortable, but it's enough for emergency evac.)

  • We can reduce the necessary emergency equipment by having frequent stations. Trust me on this for now! I'll get back to this one very quickly.

All of this put together makes Boring Company tunnels a whole lot cheaper than train tunnels.


Stations

Twice, now, I've glossed past issues with stations. The Las Vegas Loop requires stations at every stop so people can get on and off; our emergency system also requires frequent stations. These can both be solved by having lots of stations.

but wait, I thought stations were expensive Nope! Stations are cheap. Underground stations are expensive. The solution is that you just put your stations above-ground. Any parking lot can become a station terminal, as can underground floors of already-constructed buildings.

This works for Boring Company cars because car station positioning is far more flexible than train station positioning is. Train stations have to be long because trains are long; cars are short and so car stations can have basically any layout. Trains run on rails, which have extremely low friction - this is good from an efficiency perspective, but means that trains cannot handle significant slopes without expensive equipment like cable cars. If trains can't handle slopes then above-ground stations for underground rails simply aren't possible. Meanwhile, the minimum footprint of a full-fledged aboveground car station connecting to an underground network is the same footprint as a small house; a tunnel up, a tunnel down, and a few parking spaces, done.

Now we have cheap stations! We can toss a station at every casino on the Las Vegas Loop and not think twice about it. Our tunnels become smaller because we don't need as much emergency equipment, and our trips are faster because you can enter and exit from the cars in more places.

This is a reasonable solution. But it's not a great solution. We still have to drop people off at stations and pick people up at stations; what if someone doesn't have a station nearby? What if someone wants a car from their house off in a suburb or true rural area? Do we need to build tunnels to every single neighborhood, and then require that people walk across half their neighborhood to get home? It's 108 degrees out right now, I'm not walking in that weather. Screw that. And worst, we still need significant land dedicated to this system for the parking-lot terminuses, and land, as I've mentioned, is expensive.

We can do better.


Stationless Point-To-Point

This is where I move into speculation territory. But I really do think this is the plan.

We have an underground network of self-driving vehicles. We have cheap entry and exit tunnels. This is all we need to finish the entire system.

We keep our entry and exit tunnels, and we put them everywhere (which also solves our emergency exit requirements.) However, we get rid of the stations. The tunnels are simply a way of transiting from the underground network to the aboveground road network. "The aboveground road network", you ask? Sure; we're going to co-opt the aboveground road network for part of this. We're not using it for long-distance travel, so we can get rid of the giant tangles of freeways and onramps. But we are using it for last-mile travel, because it's there.

When you request a vehicle, one shows up at your doorway. You get inside and it heads to the nearest convenient tunnel entrance. Most of your trip is spent underground, and then it pops back up into the sunlight to bring you straight to your destination.

No stations, low land usage, point-to-point congestionless travel.

That's the actual goal.


Common Objections

Moved to its own comment due to character count limitations.


Conclusion

The goal of the Boring Company is to make the first fast inexpensive public transportation system. Cars are fast and kinda inexpensive, but not public; Uber/Lyft are fast and public, but expensive; trains and buses are inexpensive and public, but not fast. Elon Musk is trying to get all three at once, and the decisions being made are in service to that. The thing being designed really could not exist before self-driving vehicles; it is a truly 21st-century transportation system and hopes to redesign the urban landscape on a level that we haven't seen in a century.

I have no idea if it will succeed.

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We should have more detailed top level posts like this one. Good work and hope you stimulate more debate.

Similar to how Tesla sparked an electric car investment boom, I'm hopeful that entrepreneurs continue to tackle issues that are cost prohibitive currently but with sufficient commodity chain/labor cost reductions could become feasible. The Boring company definitely falls into one of these, blows my mind how much tunnels cost to dig in NYC per feet.

This reminds me of a charter city in South America that wanted to sell property rights to space vertically. Basically they categorize land not just on the ground but above/below properties and you can choose how many cubic meters you want to buy.

I hope this does take off, because as a Georgist I strongly agree that we need to open up more land. Even all of the innovations here aside, I would be very happy to see us take more advantage of vertical space rather than continuing to perpetuate urban sprawl. For those who want denser, walkable cities this is an unparalleled opportunity.

For those who want to spread out, well, if cities can reduce sprawl there will be more open space. More natural environment. It really seems like a win-win-win, and I haven't yet seen any concrete arguments that make me think this is a bad idea. Sure it's expensive, sure it may not work and there may be better alternatives, but I love to see billionaires like Musk throw around their weight for truly transformative ideas. As long as I agree with the idea I suppose.

l;dr: Transportation has traditionally been "fast, inexpensive, public; pick two", and Elon Musk is trying to pick all three at the same time.

Lots of cities all over the world already have this. The United States used to have this. This is not a real problem. It's a fake problem invented terrible urban planners in the 1950s. A reasonably dense city and suburbs, with a combination of pedestrian and bike infrastructure, subways, trams, and buses, can absolutely accomplish this. Your post is seriously written as if you cannot combine multiple forms of transportation in a single trip, and as if bikes and surface trams (which don't require tunnels at all) don't exist.

In addition, "inexpensive" is, at best, relative. TBC claims they're going to be charging $5 for a short trip across downtown and $10 from downtown to the airport. This is about twice the cost of using transit (e.g. Chicago charges $2.25-2.50 for most rides with 25 cent transfers, or $5 to get to O'Hare). At best, this project represents a different point on the tradeoff curve between price and speed.

There's a lot of reasons for this. Cost disease, in general, is one of the big ones, and if Boring Company gets hit by cost disease then this entire thing might be doomed. I think they're more resistant to this because they are not having cities come to them asking for services, they are going to cities to propose services, and if they're expensive, they won't get any contracts. Note that Boring Company has already turned down a contract because the company was going to waste a lot of money on things that weren't the tunnel, and they just didn't want to be a part of that. I'm going to just cross my fingers that this doesn't happen

It sounds to me like this doesn't really solve any of the most important problems. We used to have the ability to make subway tunnels for a reasonable price, and other countries still can. Technology can offset some of the costs imposed by bureaucracy, environmental review, etc. but so far the Las Vegas project seems like a one-off that got a cooperative city government to help. Basically, your actual solution is "don't build anything in cities that don't agree to cut through red tape" which has nothing to do with the Boring company. You could start a private subway-tunnel-building company and do the exact same thing. In addition, many places have non-artificial limitations on building tunnels underneath things, like water tables on the coast or crumbly bedrock around Austin. Which brings us to...

Cars are much smaller than trains [citation needed] and don't require as much sheer size.

In order to carry anywhere near as many people, you need a LOT more space. If the individual tunnels are small, then you're going to need a lot of them. As Houston's Katy Freeway has indicated, you can easily fill up several dozen lanes of car traffic on a single route and still have substantial congestion. I don't think you've solved the fundamental problem of individual cars in populous areas, namely that they use a lot of space per person.

Lots of cities all over the world already have this.

No cities have this, as near as I can tell.

I mentioned this in the post, but I'll reproduce it here:

Short-to-mid-distance buses, trains, and subways cannot match uncongested cars, and you can test this on Google Maps by going to a city of your choice, picking two positions, and twiddling with the "Start At" option until you find the fastest times for cars and the fastest times for public transportation; in almost all cases, cars are significantly faster, and I've never found a case where cars are more than a minute slower.

If you actually find this, you'll find that cars are faster. Not statistically; almost as a universal. Not in US cities; in all cities, even those renowned for public transportation.

And every time you add a new form of transportation, you're slowing things down. Transfers are slow; they cannot compare to point-to-point trips at all.

In addition, "inexpensive" is, at best, relative. TBC claims they're going to be charging $5 for a short trip across downtown and $10 from downtown to the airport. This is about twice the cost of using transit (e.g. Chicago charges $2.25-2.50 for most rides with 25 cent transfers, or $5 to get to O'Hare). At best, this project represents a different point on the tradeoff curve between price and speed.

New stuff always costs more, and it costs relative to the competition and to its own supply. TBC is already kind of overloaded in some cases; as they expand, they can drop prices, and they can drop prices based on available competition. In addition, they're still scaling up - lots of things are expensive until they get cheaper.

In addition, many places have non-artificial limitations on building tunnels underneath things, like water tables on the coast or crumbly bedrock around Austin. Which brings us to...

These aren't big issues; there are plenty of metro systems under the water table or in areas with bad rock. We've dealt with this before, we'll deal with it again.

In order to carry anywhere near as many people, you need a LOT more space. If the individual tunnels are small, then you're going to need a lot of them.

This is correct. I don't see an issue here. There's a lot of space underground.

I mentioned this in the post, but I'll reproduce it here:

I saw it, it's just wrong. Unless you are defining "fast" to mean "the speed of uncongested car traffic on a highway" or some similarly useless definition which is designed to make your argument tautologically true. Obviously no existing form of transportation will travel through a city at highway speed. There's stuff and people in the way, that's what makes it a city. But well-designed cities can be traversed, explored, and used in a very reasonable amount of time (especially once you realize that walking and cycling provide exercise, and transit lets you do things like read or work). You called Uber, Lyft, and private cars "fast" but this is only true when there is no congestion. If these mods of transportation count as "fast" when their speed during congestion (often around 10-20 mph) is accounted for, then you absolutely have "fast" mass transit. A e-bike compares favorably with that, let alone the subway, and where congestion is really bad (I think the average speed of a car in Manhattan is something like 6mph), even a casual ride on a regular bike is faster.

New stuff always costs more, and it costs relative to the competition and to its own supply. TBC is already kind of overloaded in some cases; as they expand, they can drop prices, and they can drop prices based on available competition. In addition, they're still scaling up - lots of things are expensive until they get cheaper.

The prices given are currently estimates for the future. They could go down; they could also go up, as many infrastructure projects run over-budget as time passes.

These aren't big issues; there are plenty of metro systems under the water table or in areas with bad rock. We've dealt with this before, we'll deal with it again.

Yes, but those metro systems take up much less space because a train carries many more people than a lane of cars.

This is correct. I don't see an issue here. There's a lot of space underground.

Well, in some places. But more importantly, it makes the cost much higher. You can't directly compare the cost of one LVCC-style tunnel to one subway tunnel. TBC's project in Vegas costs $47 million per 1.7 miles, or 27 million per mile. Subways can carry around 15 times as many people as 1 lane of traffic, so you would have to spend 27*15 = about 400 million per mile. This is worse than what other developed countries spend on subways, and since much of the cost of American infrastructure appears to be artificial and TBC could carefully select the best city for their test project, you should expect that actually building car tunnels in other cities would be substantially more expensive, probably on par with our subway projects.

When comparing to surface light rail, the situation is even worse for underground tunnels. Light rail can be built for similar cost per mile even in the US, while carrying up to 8 times as many people as a lane of cars.

One of the important points about the self-driving aspect is that we already have the capability to self drive cars in a tunnel.

The software and hardware are very much simplified. There are no deer/soccer balls/children to avoid and the turns are very simple.

Comparing people movement on a highway with self-driven cars in a tunnel might be a useful approximation, but there’s no reason that the tunnels can’t have 100mph cars two feet apart. If you can solve the inefficiencies at on/off ramps and keep people from braking unnecessarily, throughput should go way up.

Good posit

This is a bit of an aside but I was frankly disgusted by how many people seemed to want the Las Vegas loop to fail. Just because there was a brief slowdown in the demonstration people were acting like it was a humiliating defeat for a tech system still in its infancy. I just hate that crabs in a bucket attitude

Seriously, how many new things don't have the occasional hiccup? How long did it take the JWST to launch?

Nothing in this convinces me this is better than trams.

Why not use rails for this?

Remember, we need the ability to have inexpensive entries and exits from the system. This is both so we can provide easy emergency exits, so we can reduce the amount of surface road required for the last-mile trips, and so we can spend less land for the entire project. Rails have low friction which makes significant slopes impossible; without significant slopes, we cannot have cheap connections between underground and surface; without those cheap connections, the entire system economically falls apart.

In addition, part of how the system works is that self-driving cars can travel along residential roads to bring you straight to your destination. Rails would require that we build rails into every road in residential areas. This is just not economically feasible.

Don't need exits if you build those trams on the roads. Which suddenly makes the whole cost factor disappear either, and the "people are getting burned alive in tunnels" thing. And the "needs cars" thing.

But then you run face-first into Fast; you're stuck with slow transportation.

As others have said, if Uber solves self-driving, that would also deliver most of the benefits of this proposal. Beyond that, you're putting roads in tunnels to use the surface more efficiently, which makes economic sense in some cases but not always.

There's the capacity thing too. I did some pencil math. The best subway lines in NYC run every three minutes. Each train carries about 1500 people, making it 30k people per hour. Meanwhile, the average highway carries 2000 cars per hour per lane. Assuming 1.2 people per car, you'd need 30k/(1.2*2000) = 12.5 lanes for the same capacity. (Did a little searching, most sources end up at about 10-15 for the number of lanes.) There's no room for 12.5 extra lanes under the streets of Manhattan, nor would any city planner opt for them unless the surface was extremely valuable.

Keep in mind you don't need to be limited to under the streets; most buildings don't go that deep, but road networks can go pretty dang deep. There's a lot more "under Manhattan" than limiting it to under the streets.

I find this to be an interesting solution to travel and pollution.

If they had only their own cars, then that would make the self-driving in the lower areas significantly easier. Just have it ran from a central computer which keeps track of where they are.

In a decade when they have a bunch more tunnels, I wonder how hard it would be to carve out a walkway to the side. This would, if the surface temperature is a lot and you don't want to go in a car, let you walk in a probably somewhat temperature-controlled underground pathway. (Though, you'd then have to resolve the issue of homeless people staking out on the walkways, which isn't easy)

Moved to its own comment due to character count limitations.

it's your site just increase it

I actually looked into that! Turns out it's annoyingly hard; the character count limit is baked into the database, changing it requires a database schema change and I think the constant itself is in a lot of places.

I did set up a task to do that at some point (https://github.com/themotte/rDrama/issues/229) but I wasn't going to wait to post this.

I long assumed that Twitter's character limit was maintained due to a database schema somewhere: a fixed-size Tweet structure probably makes a lot of sense, although if you're reserving 10kB for each post here I bet that would add up quick. Although with compression perhaps that's less of an issue.

It's varying(20000), which basically means it's a length indicator and a big variable-length blob, but limited to 20,000 characters. It should be really easy to change - it's literally just relaxing the size limit - but not a change I wanted to mess with right now.

Isn't this simply lumping together two existing concepts and passing it off as a novel idea?

On one hand, you have self-driving cars, which is not a novel idea, along with carsharing and ridesharing.

On the other hand, building new limited-access roads to ease congestion is also not a novel idea.

Why will self-driving Teslas in TBC tunnels be qualitatively better than self-driving everything else on other limited-access roads?

That's part of the "price". Underground means you aren't using surface area, and surface area is expensive and valuable.

But surface roads are already there. And you yourself mentioned you can't bore a tunnel to every home and business, so the cars will have to drive to tunnel entrances on regular roads. So even if proprietary tunnels plus proprietary cars will allow Musk to greatly improve the throughput of a single lane, they will still have to compete with existing eight-lane highways that the same cars (and every other self-driving car) know how to drive on.

This's a noble dream, but it's the same dream I've heard about from boosters of self-driving cars. What advantage do the tunnels add? They'll help prevent congestion aboveground, but the whole mechanism for making them cheap is making them narrow - so a two-lane road aboveground will be just as useful as a two-lane tunnel underground.

(And that's if the tunnel can be made cheap, which I seriously doubt.)

There's a lot more room underground than there is aboveground. If we can build them cheaply, then we can build huge amounts of them cheaply. Land prices are a major part of highway costs, and in theory that price just kinda vanishes, and we still don't have to spread things apart more in order to make room for roads.

If we can build them cheaply, yes. Perhaps I should look closer, but I haven't been convinced. Land for tunnels isn't as expensive, but whole new costs would show up for excavation and support.

We've actually gotten really good at building cylindrical tunnels; we basically put a machine in, run conveyors in and out of the hole, and then just let it run while we feed it raw materials. Part of the goal of the Boring Company is to cut way down on the manpower requirements of this.

And surface roads are shockingly complicated - it turns out the ground is very difficult to build things on.

What are the maintenance costs of tunnels as compared to above road infrastructure? They are obviously less susceptible to weathering. I guess this would also factor in to reduce or increase the opportunity cost.

Yeah, the lack of weathering and erosion is big. I'm not sure how big. There's reasons to believe it will be both more or less expensive; I'm personally calling this equal, just because I have no reason to strongly believe otherwise.

This is how the Boring Company is going to solve tunnel price:

  • Cars are much smaller than trains [citation needed] and don't require as much sheer size.
  • Cars travel on concrete, not rail, and this surface is perfectly suited for passenger exit, meaning that you don't need an extra passenger lane as long as there's enough room to get past the cars. (Note: in the current Loop tunnels, there is, even though it's not obvious in a lot of the videos that have been posted. It's not comfortable, but it's enough for emergency evac.)
  • We can reduce the necessary emergency equipment by having frequent stations. Trust me on this for now! I'll get back to this one very quickly.

All of this put together makes Boring Company tunnels a whole lot cheaper than train tunnels.

I'm not sure I believe this. The current FHWA guidelines for vehicle tunnels requires exits at no less than 1000 ft spacing (which is plausibly close to your station spacing), and requires a 3.6ft wide protected pedestrian egress walkway -- not just squeezing past potentially burning vehicles. That's pretty clearly not done for Musk's tunnels, nor is it easily plausible with their existing boring machine sizes. There are no shortage of tragic accidents involving tunnels, and EV fires are particularly concerning in some ways.

Honestly, I would tend to cite Thunderf00t's rant about why the Boring Company is ill-advised in its adventures.

Honestly, I would tend to cite Thunderf00t's rant about why the Boring Company is ill-advised in its adventures.

He's ridiculously obsessed about Musk tho.

Keep in mind that the FHWA guidelines are not legally binding, and are not designed for anything of this sort; they're intended for standard highway layouts, and they're ignored and stretched all the time anyway (check out the Lærdal Tunnel, which I guarantee does not have an emergency exit every 1000 feet.)

If you have multiple burning cars in the tunnel you're probably boned anyway.

Common Objections

But hold on, in this plan we still need roads.

Yeah, we do. But we need roads anyway.

We need roads for emergency vehicles. We need roads for utility vehicles. We need roads for cargo delivery and for oversize transport. I just replaced my roof; how are you planning to get a full pallet loaded with tons of shingles to my doorstep any other way?

Roads are useful and they're not going anywhere. But a lot of these things don't require big roads, they require some roads. In the eventual future, the plan would be a dramatic reduction in road width; two-lane residential roads become one-lane residential roads, four-lane arterials become two-lane roads, highways mostly vanish.

If they must exist, and they must, then we may as well make them do double-duty. Below a certain threshold of usage, roads cost money simply by existing because they require regular maintenance to protect them from the elements. Usage up to that threshold is free, and using them just for the last-mile trips is going to be very light usage compared to how they're used today.

Why not use rails for this?

Remember, we need the ability to have inexpensive entries and exits from the system. This is both so we can provide easy emergency exits, so we can reduce the amount of surface road required for the last-mile trips, and so we can spend less land for the entire project. Rails have low friction which makes significant slopes impossible; without significant slopes, we cannot have cheap connections between underground and surface; without those cheap connections, the entire system economically falls apart.

In addition, part of how the system works is that self-driving cars can travel along residential roads to bring you straight to your destination. Rails would require that we build rails into every road in residential areas. This is just not economically feasible.

Isn't this last-mile travel still going to cause problems in downtown areas?

While I've been describing surface entrances and exits as the normal way of getting in and out of the system, you don't have to use surface exits. Skyscrapers already have enormous basements, and you don't need more than a single floor to build a terminus. In this case you really could have stations, located in multiple building basements; the car delivers you straight to your workplace and you go straight from car to elevator.

Cars pollute, and this is still going to cause lots of pollution.

There's no way this is going to be based on internal combustion engines - that makes tunnels far more complicated to begin with. All electric, all the time.

Electric does not solve the problem entirely. A significant source of car pollution is actually particulates from tire wear. But a lot of the tire wear will be localized within tunnels, and can be swept up and disposed of much more efficiently.

The mass number of cars required isn't going to be cheap or great for the environment. But it may be better than subways. Your average subway car costs almost a hundred times more than a single car, and costs similar amounts more to maintain. Fleet cars gain huge advantages from massive mass-production and you simply cannot do that with subways. In addition, subways often run mostly empty, and the cars in this system will rarely be running empty; a car sitting waiting for a passenger is not polluting, while a six-car subway train carrying a total of three people is polluting quite a bit.

Don't you still need big parking garages in downtown areas?

Maybe! The actual numbers are currently unclear.

But this isn't as big a problem as it sounds. If we have cheap tunnels, then we can make dedicated parking tunnels. Fleet cars are entirely homogenous, and we never need to access any specific car, we can just cram a bunch of cars in a tunnel and do first-in-first-out retrieval as they're requested.

We don't even need dedicated parking tunnels. Because these are all computer-controlled, we can dynamically reprovision transport tunnels as they're not needed. Maybe we need four parallel tunnels in one area for peak hours; well, once the peak is done, we can turn that into one travel tunnel and three storage tunnels. As it gets closer to peak, clear out a storage tunnel and turn it back into a travel tunnel.

A lot of this is very much hypothetical and requires a lot of software development. But it's all software, not hardware; this can be improved as the system grows.

Wouldn't you need to build the entire thing all at once, just to find out if it works?

Not at all!

The Las Vegas Loop is a good example of this. You can build one tunnel, then connect another tunnel to it, and just keep on going. Cars don't require complicated switching systems like trains do, and computer-controlled cars don't require complicated signage. In practice I expect this will generally start with the backbone of a city, then get expanded as it gets used, in order to move more traffic off streets and into the underground.

How expensive does this actually end up being?

Nobody knows!

Seriously, nobody knows. This is all quite experimental. I made an argument above that Boring Company tunnels will be a lot cheaper to build than train tunnels, which is, I think, true. But you'll need more Boring Company tunnels, because each one is incapable of holding as many people as a train tunnel, and we expect more people to use them, and we expect people to travel longer distances in them too. It adds up fast.

Traditionally, this is handled by trying to buy property, then eminent-domaining it if necessary, usually with some detours through poor areas to cut down on price and voter dislike. But this is the old model where building a station requires knocking down a building. If we're going completely underground without needing that aboveground work, this should be cheaper.

Subsurface rights are complicated; some properties technically own all the land beneath them, some properties (especially in Texas) own only a few feet down and the rest is owned under "mineral rights". Some cities explicitly reserve the right to run underground utilities under your property without consulting you. Even if you do own the rights, eminent domain can still apply, and how many people are really going to object to getting a few thousand bucks in return for a slice of rock a hundred feet down?

Often train tunnels get run under roads as much as possible, specifically to avoid the ownership issues. Low-speed car tunnels are more agile than train tunnels, able to make tighter curves and hug the road network better than trains. High-speed car tunnels aren't, but they can be run deeper, which is likely to cause fewer property arguments.

I'm reasonably confident that property costs won't turn out to be a big problem, assuming the Las Vegas Loop turns out well and other cities start salivating at the idea of their own Loops; minor things like "unused property rights" tend to fold quickly in the face of government interest. Practically, though, we won't know until the lawyers are done with it.

Isn't this the same thing as that vacuum-tunnel Hyperloop idea?

Nope! But I can't blame you for being confused.

The Las Vegas Loop has, officially, nothing in common with Hyperloop, besides the word "loop" and the fact that both of them are intended to move people. Elon Musk has mentioned that he wants to put some effort into building Hyperloop tunnels with Boring Company but so far he's done nothing more concrete than speculation.

I think, assuming Hyperloop can be made to work, it could turn into the long-distance leg of a country-spanning network using Loop as the short-distance part. Don't hold your breath on that one though; in a post that is almost entirely speculation, that is, like, speculation-squared.

In this model, you can't own your own car, and people won't like that.

Nothing stops you from owning your own car! Boring Company has said that they would allow privately-owned cars in with the appropriate self-driving software. I suspect most people wouldn't own their own cars, but if you want to spend the money on it, you're welcome to do so.

In addition, the ground road network does still exist! Likely cut down quite a bit, but only because of a lack of demand; if you want to use it, you're welcome to.

Is there anything you couldn't find a good place for but want to mention anyway?

Yeah: Weather!

In some areas of the world, traditional roads are very expensive to keep clear and have constant maintenance burdens due to freeze/thaw cycles. Putting the roads underground reduces the impact of weather and may cut down on maintenance costs considerably long-term. This also protects cars from weather, improving driving speeds during rain and snow.

(Comedy option: install air curtains at every entrance and exit, then heat the entire underground section from waste heat in order to reduce per-vehicle vehicle heating costs. I have no idea if this would be cost-effective.)

There's potentially a flooding problem during extremely heavy rains and, obviously, on coastal flood-prone cities. Similar to how aboveground roads have to shut down during heavy snow, the underground network would probably just have to shut down during flood conditions.

In general I suspect this ends up being a net improvement, although it obviously isn't a panacea.

Are you getting paid for this?

I own Tesla stock, and I would own Boring Company stock if I could. But besides me buying some of Tesla's stock, I have no further relationship (that I'm aware of, at least!) with any Elon Musk company.