October 2009

It’s true, transit share is a distraction, and thanks to John for the shout-out.

BUT — and this is a digression I was trying to avoid in my previous post — we’re just talking about the relatively narrow issue of where to invest dollars to add peak capacity to the network most cost-effectively. If that’s your sole goal, you may end up with a system resembling DC’s Orange Line, with park-and-ride stations built on a highway median.

Not that there isn’t a place for that here in Seattle (the park-and-rides Sound Transit is building along I-5 are quite nice), but there’s a lot more to transit and land use and such than simply adding commuting capacity.

In other words, what Secretary LaHood said.

As we update the land use codes in an effort to make the most of our given built environment, inevitably discussions turn to the 4-pack, the Seattle townhome design that’s sprouted up all over the city over the last 10 years.

Great City has a link to the Congress of Residential Architects’ proposed solutions to the 4-pack conundrum. The report is interesting in that it separates a bunch of proposed townhouse designs into “white hat” designs that attempt to preserve the spirit of the code, and “black hat” designs that attempt to exploit it.

For my money, the last page (which I’ve excerpted as a PDF) is the one that’s really worth focusing on. It shows, step by step, how rigid land use codes lead, inexorably to the current townhouse design, and asks the fundamental design question: what trade-offs are you willing to make to change this?

Last week, John Niles, oft-quoted rail critic, tweeted:

With more rail & TOD, higher fuel prices, & more climate awareness, why can’t PSRC write 2040 Plan to double transit market share?

Good question! Fortunately, the plan Niles is talking about does exactly that… where it counts.

Niles is referring to this chart (PDF):

The transit share of “all trips” increases from 2.9% to 5.2% under Alternative 5 . But the share of “work trips” shoots from 10.4% to 19%. That’s pretty close to doubling, and significantly more than the baseline scenario.

As I commented on the Cascadia Prospectus site (where they’re equally confounded by the plan), the reason that this is important is that it’s the work trips that cost us all the money. If someone needs to run out for milk in Issaquah at 10pm, sure, that counts as a “trip,” but it’s not really an expensive trip from a peak capacity perspective, because the roads of Issaquah aren’t clogged at 10pm.

The trips that are expensive to add capacity are the peak, “work” trips. And for those trips, additional transit service and right-of-way is the only realistic way to add enough capacity.