
There has been a lot going back and forth about density, so I’d like to write about it yet again. My basic argument about density with relation to transit is that transit creates density, not the other way around. New York had 500,000 people when it’s first railway was built in 1849 , 617,000 people subway was built in 1869, and had 7,891,957 people 80 years later in 1950. London had 1.35 million in 1831 when it’s first railways were built, had 2.5 million when the tube began construction (in 1863) and had ballooned to 8,615,245 76 years later (1939).
So when you here about transit and density, think not about how much density is required to support fixed-guide-way mass transit, but instead think about how much construction will be built around that transit. Case in point: Saturday the New York Times ran this piece about transit oriented development in Utah.
Murray City and Hamlet Homes are taking advantage of growing buyer interest in living and working near the regional TRAX light rail system, which has operated in the Salt Lake Valley since 1999. The Murray North station, one of three TRAX stops in Murray City — population 50,000 — serves as the centerpiece of Birkhill at Fireclay.
…
Salt Lake City and its closest suburbs built the $520 million, 19-mile, 23-station TRAX system, which carries more than 55,000 riders a day, well ahead of ridership projections. Voters have also repeatedly passed sales tax increases, including one approved last November, to spend $2.5 billion more in the next decade to complete 26 additional miles of light rail, 88 miles of heavy commuter rail line and nearly 40 extra station stops. The only American metropolitan area that is building more regional rapid transit capacity is Denver, which is constructing a 151-mile system.
Uh, does it seem to me that the low density places like Utah and Denver benefit more from new rail already high density places? Development is relatively easy, there is more community transformation and it is easier to obtain rights of way. In fact, one of the reasons that was so cheap was the right of way was an abandoned railway. Sounds a bit like the BNSF corridor on the Eastside, doesn’t it?
So you may think that means that high-density Seattle won’t get much out of transit. But Seattle is actually relatively low density. People get confused because the downtown core is so dense, they think that Seattle is a dense city. It is not. I have compiled this table of city densities with how populated Seattle would be if it were that dense.

As you can see, even epitome of sprawl Los Angeles is far more dense than Seattle. In fact, Seattle would have 700,000 people (by my calculations), instead of the 580,000 it has now, if it were as dense as Los Angeles. Seattle is about like Cleveland and Detroit, not cities I think of when I think of dense.

Despite it’s recent condo boom, Bellevue is far to the low end of cities, though it is probably unfair to compare a satellite city to main ones. The point remains, this is a low density region, and mass transit won’t have quite the effect here as it had in London or New York, but I imagine with enough transit built Seattle could easily get to be as dense as San Francisco or Chicago, in the one million people range.
Here’s a decent argument from Clark Williams-Derry (of Sightline) about how transit works in Vancouver, and how it could work here from the Tacoma News Tribune.
But when density rises a bit, transit becomes viable. By clustering homes near transit stops, and mixing residences with stores and services, neighborhoods in greater Vancouver have created more opportunities for convenient, cost-effective transit service.
Data from the Canadian census shows that roughly two-thirds of greater Vancouver’s residents live in a compact neighborhood – the sort of place where transit begins to be convenient and reliable. At last count, only about one-quarter of the people in the greater Puget Sound region live in that kind of compact neighborhood.
Transit doesn’t solve everything, of course. Despite its transit-friendly neighborhoods, greater Vancouver’s traffic is still pretty darn congested. Still, even if Vancouver’s focus on transit-friendly neighborhoods hasn’t guaranteed breezy commutes, the effects have almost certainly been worthwhile. First, without Vancouver’s transit edge, the city’s commuters would almost certainly be worse off than they are right now. If you lowered Vancouver’s transit ridership to Seattle-Tacoma levels, tens of thousands of additional cars would flood their roads during peak hours – the very time when they’re already jammed to capacity.
He’s got the argument backwards as I keep pointing out. Vancouver wasn’t dense before they built Skytrain and other transit options, it became dense when transit became more reliable. The argument about lowering Vancouver’s transit ridership is silly, because if they had never built Skytrain, Vancouver and it’s suburbs wouldn’t be nearly as dense as it is now, with far more sprawl, and far fewer compact neighborhoods. Building transit here will allow for more density. It certainly won’t solve everything, but more roads won’t either.
Clark Williams-Derry does have this nice point:
And finally, Vancouver’s transit-friendly neighborhoods have kept residents safer. In Washington, car crashes are the leading killer of people under the age of 45. But Pierce County residents are 70 percent more likely to die in a car crash than are residents of greater Vancouver – not because the roads are less safe, but simply because residents in counties like Pierce have to drive so much. (Mile for mile, riding a bus is about 10 times safer than driving a car.)
Well, I will feel a little more safe aboard the bus tomorrow.