Here’s a great argument for public transit, in a single image: Check out how gnarly it’d be — and how many dang bridges New York would have to build — if the estimated 2 million-plus people commuting in and out of Manhattan during rush hour each day drove their own cars:

According to an analysis by Vancouver-based highway design engineer Matt Taylor, the city would need a whopping 48 additional eight-lane bridges to accommodate such a travesty.

The next step to his analysis — parking — suggests that if as many people also needed off-street parking, there’d be 62 square kilometers (or almost 24 square miles) of parking space, “equivalent to a layer of underground parking underneath the entire island.” If local residents also drove, he estimates, they’d need TWO layers.

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Luckily for New York, though, just 16 percent of commuters actually drive their own vehicles to work these days, and few local residents drive: New Yorkers average about 23 cars per 100 residents, compared to about 78 for the rest of the country. (Though maybe it’d get even better if Manhattan went the way of Paris and started banning cars entirely?)

Anyway, thank goodness this is just a rendering; research repeatedly shows that when we build more roads, all we get is more traffic. We shudder to imagine the gridlock.

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