Envision Houston, part 3 - The Four Basic ApproachesContinuing from yesterday, today I'd like to comment on the four basic approaches I saw in most peoples' planning maps at the Envision Houston event last Saturday. Teams were asked to write their philosophy and goals in the margin of the map, but they basically seemed to fall into one of four approaches, which I categorize based on a two-by-two grid of concentrated vs. dispersed jobs vs. residences.
1. Concentrated Jobs, Dispersed Residences
This is basically extending today's approach forward: people live in the suburbs and commute into the core to work. A lot of people seem unhappy with this approach: it strains transportation infrastructure (traffic congestion) and it consumes a lot of land for single-family home residences ("sprawl"). On the plus side, people get affordable homes, high-capacity commuter transit is more feasible with concentrated job centers, and it keeps us a more unified city (when people work in the core, they feel tied to the city and support it more, especially nonprofit institutions). I think New York and Chicago may be the perfect examples of this model with commuter rail, and Houston may be the premier example in the country based on freeways/HOV lanes.
What these types of cities wish for: shorter commutes.
2. Concentrated Jobs, Concentrated Residences
A very popular approach at many of the tables: pack more high-density residential areas into our core to go along with the existing core jobs. Classic Smart Growth. This uses less land, reduces sprawl, gets more out of existing city infrastructure, and makes core transit more feasible (density supports transit). Unfortunately, the data from other cities shows that, as density increases, transit usage increases relative to car usage, but not as fast as the density increases, so you actually get a lot more car trips per square mile - i.e. traffic congestion gets a lot worse, especially on surface streets. LA and DC are good examples of this kind of traffic impact. It's also unclear how many people are willing to choose dense living over the traditional single family home. Home affordability is a big problem in many smart growth areas. (here's an article on how it's impacted Sydney)
What these types of cities wish for: parking, affordability, faster trips.
3. Dispersed Jobs, Dispersed Residences
I think of this as the "DFW Metroplex model": spread jobs and residences far and wide. The metro areas of Atlanta, Phoenix, LA, and the SF Bay Area also fit this model. There is a certain logic to it: people often live closer to their jobs, and you're not trying to move masses of people into and out of the city every day. Unfortunately, transit becomes very difficult if not impossible because of the low densities of jobs and people. There's still plenty of sprawl, and there's still plenty of traffic: people change jobs and don't want to move, or their spouse has a different employer across town. Sometimes the traffic gets so bad that people are pretty much forced to move every time they change jobs, which can be pretty frequent in today's economy, and I think this is very detrimental to long-term community-building. I also think you can lose a lot of unity and end up with a fragmented region, with various municipalities and counties squabbling with each other. There's no critical mass focused on a core. While each small community might have a sense of place, the metro region as a whole often does not: the classic line, "there's no there there".
What these types of cities wish for: a "real" 24/7 downtown with a "sense of place".
4. Dispersed Jobs, Concentrated Residences
Think of this as lots of "town centers" around the region with high-density New Urbanist residences around pockets of jobs. Often this is implemented as high-density "transit oriented development (TOD)" around rail stops. People can even bike or walk to work within the TOD, which mitigates some of the surface street traffic problems of approach #2. Arlington, VA outside DC is the best example I can think of. Still have the question of how many people want to live at that density, the home affordability problem that often accompanies density (although probably less of a problem than #2), and the freeway traffic and fragmentation problems of #3 (although these may also be less of problem in the TOD case).
What these types of cities wish for: this one's not as obvious to me - maybe a milder version of #2: parking, affordability, faster trips? In my mind, model #4 is the least clear cut of the four approaches in terms of pros and cons, probably because it's been done in so few places (it's the exact opposite of the normal model). Would love to hear your thoughts in the comments.
Tomorrow, I'll talk about how Houston might mix-and-match from these four models.
(sorry for the posting delay on this one - Blogger wouldn't publish new posts last night)