Mapping what SF would be like if it were as dense as New York, Paris, and Manila

Just 200 years ago San Francisco was as vacant and obscure a spit of land as almost any in the world. And when locals can’t get a seat on the 38 Geary during rush hour, they probably wish it was still. But our overwhelming urban density could always be denser.

A blogger for the storage site Sparefoot got curious about what the city might look like if it was as densely populated as a few cities abroad (and one on the East Coast) where close quarters squeeze even closer than ours.

Using a population estimate of 864,816 (based on the census estimate from July of 2016) and granting the city 47 square miles of space, Sparefoot crunches out a density ratio of 18,440 San Franciscans per square mile.

Note that locals have disputed exactly how many square miles San Francisco is for decades.

Back in 1999 the San Francisco Chronicle attempted a definitive figure, coming up with 47.355 square miles, including Alcatraz, Yerba Buena Island, and Angel Island (but not the Farallon Islands.)

So that comes out to 18,262 people per square mile. But the city’s dimensions have always been in the eye of the beholder, give or take.

In any case, here’s what San Francisco would look like with a 2016 population but New York City’s calculated density of 28,256 people per mile:

(Again, New York City is evidently two square miles shorter than most people seem to think—302.6 miles—so the number here is bit off, but close enough.)

And here’s how much smaller SF would have to get to equal Mumbai’s roughly 53,000 people/mile:

Note that Mumbai’s population is another source of regular dispute.

Here’s the city packed into enough space to equal Paris’s 55,000/square mile:

And Manila’s panic-inducing 107,497/mile:

On the other hand, check out the Sparefoot maps comparing SF to the likes of Jacksonville, Florida and Anchorage, Alaska to get some perspective on how much roomier some folks have it.

That New York map should give the city particular pause. After all, the city is growing, generally by about 11,000 people per year.

At that rate we’ll reach New York density in 2060 or so, with a population of over 1.33 million. Of course, growth will not remain constant for decades on end; but a San Francisco as dense as New York in a few decades is nevertheless entirely plausible.

On the other hand, we wouldn’t start looking like Manila until 2400 or so. Since that would mean a population of over 5 million, chances are it’s never going to come up.

In the meantime, enjoy the wide open spaces.

• Visualizing SF Density [Sparefoot]
• SF Population, 2016 [Census]
• Just How Big Is SF? [Chronicle]
• NY Population, 2016 [Census]