What is urban, and does it matter?

I recently saw a dispute between commenters on a blog post over what exactly constituted “urban.” This dispute raised a good point in my mind. Such a discussion is an interesting one, and an important one, on some level. However, discussion of whether or not our cities’ development is “urban” is in dire need of context. It was cited in a comment at this post that urban areas must primarily serve pedestrians, with cars only a secondary concern or not a concern at all. Density would obviously figure prominently into this. Others, including Jane Jacobs, have suggested that density alone is sufficient. Still others would indicate that urbanity is signaled by street activity, not just pedestrian friendliness or density.

Regarding the development of cities, these aren’t the questions that should be asked. Rather, is “urban” in fact what our cities need, and in what form? What parts of our lives does such development improve, and what interests does it serve? How does it affect our lifestyles? What role does the market play – i.e. is the market inclined to provide and/or accept such development, and why or why not?

At this point in time, our urban landscapes are quite varied. For example, in Austin, they include these widely disparate areas:

• Downtown, primarily an employment center and a regional destination for restaurants and other entertainment, but with a couple thousand residents (most of whom I’m guessing have cars) as well;

• Central Austin neighborhoods (such as Brykerwoods, Brentwood, and Allandale) with a lot of single-family housing, but some multifamily as well, some, but not strict, separation of uses, often characterized by walkable grid-like street systems and strip-oriented commercial development (but not entirely), which in many cases is set up (or retrofitted as the case may be) to serve both pedestrians and cars somewhat well;

• New urbanist developments like Mueller, denser and more walkable than most single-family neighborhoods, with some, but not too much, mixing of housing types, and little proximity to non-residential development at this time (but Mueller has plans for it in a residential area, albeit more or less concentrated in a centralized location)

• Larger suburban single-family subdivisions, such as Anderson Mill in Northwest Austin, many of which have large lots, but even in subdivisions that don’t, street grids that don’t lend themselves to walking, entirely separate from other types of development – and their counterparts, the large commercial developments on arterials and highways, concentrations of many businesses and lots of commercial space, serving almost exclusively cars and not accessible or friendly, for the most part, to pedestrians.

Most planners, architects, and even people who read these kinds of blogs would agree the last type is something we’re trying to avoid at this point. However, all of these types of neighborhoods remain popular, and all except the last still are admired by a wide range of groups, including planners, politicians, developers, and urban boosters (sources for this?). Perhaps this variety is what our society needs. It ties in closely to Richard Florida’s creative class theory – according to Florida, “successful places do not just provide one thing; rather they provide a range of quality of place options for different kinds of people at different stages in the life course. Great cities are not monoliths; as Jane Jacobs said long ago, they are federations of neighborhoods.” In short, successful cities have something for everyone. We are becoming more racially diverse as a nation, a higher percentage of people are getting married and having children later in life, if at all; some are having fewer children. Our elderly population is increasing as well due to the aging of the baby boomers. Thus, perhaps this variety is what will best serve our society as well as our cities in general.

New Urbanist developments such as Mueller are highly walkable and feature parkland and public spaces prominently. These developments tend to be isolated from other uses, effectively separate land uses, or are not designed to connect well with nearby areas, limiting their true walkability. Instead, many have a more insular approach, and appeal to those who like the idea of “community” and believe their designs add to it; most likely, many residents of New Urbanist developments prefer that their community doesn’t relate well to neighboring land. This is reflected in the housing stock in developments like Mueller, which is mostly large single-family homes, albeit with some townhomes (which are still pretty large) and an apartment building all the way at the other end of the development. These developments likely appeal more to young married couples, many of which have very young children (I live in Mueller and seem to be one of the few who isn’t married with children).

Neighborhoods like those in central Austin appeal to such young families as well, but are likely to present a more diverse housing stock, in terms of size and age, and due to this, may be more accessible and desirable to singles or older people. They are also likely to be denser than suburban areas at a variety of scales, adding to their walkability and access to public transit.

Areas like downtown seem to appeal to higher-income people, most of whom are single or at least without children. Residents of such areas can afford the high rents they must pay to live in the area’s central commercial district, and value their proximity to urban amenities, which they are able to make more use of due to far fewer demands at home. However, despite the fact that access to public transit is usually better in downtown areas than anywhere else in the metro area, downtown’s overwhelmingly high-income residents likely drive anywhere more than a few minutes’ walk away.

How much are we self-selecting into these neighborhoods (i.e. we move to them because they suit our preferences/needs)? In contrast, how much is our behavior driven by where we live?

Central to even beginning to answer these questions is the transportation/land use connection. That is, a central question is how much do our environments affect our travel patterns? In certain ones, we need to travel by car less, and less far, but do we? Another related question is, to the extent environments can’t induce less motorized travel, what percentage of people would like to be living in more dense, walkable environments, and aren’t already?

A paper by Cervero and Kockelman (1997) illuminates the complexity of the transportation-land use relationship. Cervero and Kockelman separate into factors variables based on vehicle miles traveled, and put together predictive models for VMT and transportation mode choice. Using the best travel data they can find, their work is still subject to aggregation bias, compromises to achieve decent sample size, and variables that provide imperfect descriptions of what they’re trying to measure. However, it does confirm to some extent the effect of density on VMT (as well as the effect of pedestrian-friendly design on VMT as well, but to a lesser extent). As much as anything in the predictive models, the control variables, which included some demographic variables, provided the predictive power. (Only a slight increase in r-square occurred from addition of the design, density and diversity variables.) This would support the idea of a variety of urban environments within a city – provide those who are inclined to walk, bicycle, or take transit (lower-income, younger, childless, etc.) dense, walkable environments, and don’t worry too much about traditional suburban-style subdivisions for those who will drive anyway.

Questions still remain after this short and incomplete analysis, though. First, are such environments available in terms of affordability and accessibility to all those who would fully utilize the opportunities for non-motorized travel such areas afford them? Second, for individuals that will drive anyway, are suburban subdivisions actually better, for them and for everyone else? Finally, in the words of the authors of the article, “any relationships that are covered are necessarily associative rather than casual.” How do we measure a neighborhood’s, let alone a city’s, overall success in making places accessible for everyone, while keeping factors like VMT to a minimum?

Thus, in evaluating what types of neighborhoods to build where, there are several factors to consider. What is its perceived aim (a speculation is that Mueller aims to be self-contained, with walkable streets, recreational areas and plans for additional stores and services, but mediocre connectivity to adjacent areas)? To what extent could it feasibly achieve that aim (does it truly allow for a certain travel pattern or behavior pattern, or make compromises for whatever reason)? Finally, to what extent is it likely to achieve that aim (i.e. will the behavior of its residents actually follow)?

More importantly, to find the answers to creating better cities, we must ask the right questions. That doesn’t happen nearly often enough.

Reference: Cervero, R. & Kockelman, K. (1997) Travel demand and the 3ds: density, diversity and design. Transportation Research Part D, 2, pp. 199-217.