Everyone knows the legend of the Los Angeles streetcars (thanks to Who Framed Roger Rabbit?, mostly): in the first half of the Twentieth Century, the Red and Yellow cars criss-crossed the region and LA was almost entirely accessible by public transit. But then cars arrived, then freeways, service declined, and eventually the whole network was shut down and ripped out. The last streetcar stopped running 51 years ago, in 1963, but two economists whose work focuses on cities have found that the old streetcar routes still make a huge difference in the way Los Angeles is set up today: "we found that places near now-extinct streetcar stops remain notably denser today," they write at Zócalo Public Square.
Economists Leah Brooks and Byron Lutz calculated the distance from every one of LA County's 2.3 million properties to the nearest ex-streetcar, then plotted those distances against the population density of each property's neighborhood; they found that "Locations less than half a kilometer from the extinct streetcar are more than twice as population-dense as locations two kilometers from the extinct streetcar." They also plotted distance against the number of people living at each property and found that "population density near streetcars comes from having many housing units on land, not from having more people per housing unit." Meaning areas near ex-streetcars are more developed than areas further out.
The pair also used US Census data back to 1940 to show that areas near streetcars were denser back then and are still denser now (as LA as a whole has gotten denser too). This graph shows population density at various distances from old streetcar routes; over decades, you can see that areas just .3 kilometers from a route have consistently stayed denser than areas further out.
"Why," they ask, "after almost 100 years and the addition of literally millions of people to the metro area, does the population density of neighborhoods still reflect the extinct century-old transportation system?" Mostly, they've found, it has to do with zoning and "the self-reinforcing economic benefits of density," aka agglomeration. Areas near old streetcars are more likely to be zoned to allow dense residential development (25 percent more units) and to allow non-residential uses, like shops, that make an area more livable.
But since Los Angeles is a strange inverted city where people come in search of lots of land, privacy, and lack of interaction with their neighbors (that whole car thing), it's "relatively lower income people" who tend to live in the areas around ghost streetcars and benefit from the density found there. Now we'd love for Brooks and Lutz to analyze the new Metro train system; the development frenzy around the Red, Purple, and Expo Lines over the last few years seems like it might be creating a much more expensive version of density, accessed by convenient non-extinct transportation.
· Long Dead Streetcars Still Shape L.A. Neighborhoods [Zócalo Public Square]