Density and moving people around in density is the most critical innovation and economic enabler. The city is technology, and a force multiplier. So is transit:
“Every time a metro area added about 4 seats to rails and buses per 1,000 residents, the central city ended up with 320 more employees per square mile — an increase of 19 percent. Adding 85 rail miles delivered a 7 percent increase. A 10 percent expansion in transit service (by adding either rail and bus seats or rail miles) produced a wage increase between $53 and $194 per worker per year in the city center. The gross metropolitan product rose between 1 and 2 percent, too.
On average, across all the metro areas in the study, expanding transit service produced an economic benefit via agglomeration of roughly $45 million a year — with that figure ranging between $1.5 million and $1.8 billion based on the size of the city. Big cities stand to benefit more simply because they have more people sharing the transit infrastructure. They also tend to have more of the traffic that cripples agglomeration in the absence of transit.
‘As to how big it is,’ says Chatman of this hidden economic benefit, ‘it’s most likely to be large in places that have congested road conditions, transit networks that are at capacity — those kinds of places — and probably less in smaller cities without very much road congestion.’
Chatman stresses that because his method is so new, the results must be replicated before they’re accepted. He also knows that some people will question the causality of the data: How can the researchers know, for instance, that transit alone is responsible for agglomeration? In response, Chatman points to the controls he and Noland installed in their statistical models — and to the fact that he’s been critical of rail as an economic investment strategy in the past.
‘Put it this way: I’m a skeptic on this stuff, and I was surprised to see these results so robust,’ he says.”