Is it fair for cars to use public space?

Does anyone really know how much space cars occupy compared with other urban means of transportation? Perhaps the reality check will help to establish a better understanding.

So, let's write some numbers. In densely populated cities, the most effective mode of transportation is the subway. The "standard level" subway can transport 60 thousand people per hour. I'm talking about "ordinary" subway lines, such as those in new york, London, Paris or Milan. I'm not talking about external monsters like Moscow, Seoul or Tokyo. Their transportation capacity is twice that of the former. You will find that this comparison is unfair enough.

In order to transport 60,000 people in an hour, the subway needs: a tunnel with a diameter of usually 5 to 8 meters, and two railway tracks, one in one direction and the other in the other direction (although some modern subway trains run on concrete tracks and the trains have rubber tires).

A large number of stations have at least 40 trains every 800 meters (1/2 miles), each train has 6 carriages, and each carriage carries no less than 250 passengers, so the train interval is 1 minute 30 seconds, and each train carries 1500 passengers.

The power supply system is the power supply system that can provide energy for so many trains, as well as some supporting facilities, such as stations, maintenance stations and everything the trains need. From all aspects, the subway (this is in Delhi, India) is the most effective mode of transportation in the city.

Now, people walk to the subway station, or through ground transportation, they go underground and then suddenly appear in other parts of the city. From then on, they will walk to their destination or take other ground transportation. Between the two sites, they will not generate any traffic. They are invisible and disappear into the darkness of the city. Now let's see what it takes to transport the same number of people by car within the same distance.

First, you need a car. Since the average number of passengers per vehicle is 1.3 during rush hours (this average time varies with cities, but the peak hours are almost constant in major cities around the world, including 1.2 to 1.5, and the lower data is applicable to rich countries), you will need 60,000/1.3 = 466. This is a considerable number. Think about it, we have to replace 40 trains: each train needs more than 1000 cars to provide the same capacity.

Now we need roads. How many/much? A highway can run 2000 cars per hour. In order to carry 46,000 cars, 46,000/2000 = 23 lanes are needed. All 23 lanes are crowded with cars, which is close to congestion. Terrible! It is very difficult and inconvenient to build expressways with more than five lanes in each direction, so in order to accommodate 23 lanes, you need five expressways. Five 40-meter-wide urban expressways will replace ... a railroad track!

Only five such cars can replace a double-track metro! That's not all: after the subway train reaches the end, it reverses direction and then starts in the opposite direction. Yes, they are reversible and don't even need rotating circles. They only need to park at night, and it is an ordinary place on the edge of the city, where almost no one will go. And the car needs to stop at the destination. This means that thousands of people come and go here in the city center, CBD, business district and the most valuable section of the city, and the land here is sold and rented at the highest price.

How much space does the parked car need? 46,000 vehicles, 25 square meters for each vehicle (this is the space required for each vehicle, including motor vehicle lanes), which is equivalent to 1 150,000 square meters, that is,115 hectares, that is, 290 acres. This is the area of 150 football field, or the 230 football fields that Americans look at this answer (yes, football fields are smaller than football fields).

Therefore, by building a subway line in your city, you will save five destructive urban expressways and an area covered by parked cars in the city center, which is equivalent to more than 200 football fields.

Think about it, if this space is not occupied by cars, there will be many wonderful things here, but isn't the subway line very, very expensive? Of course they are! The cost of a subway line per mile is about $65.438 +0.5 billion, and the whole process is turnkey, including trains and stations. Usually its cost is much higher than this, because of the problems they are encountering (few subway lines are built at the planned cost).

But aren't urban highways and parking lots expensive? A city expressway with 10 lane will cost as much as150,000 USD per mile, and five expressways will cost 75 million USD per mile. This is still only half the cost of the subway line. If the expressway is elevated, the cost will rise sharply, which can be doubled or tripled (considering the scale of multi-level intersections).