Streetcar Suburb Design, Illustrated
Yesterday, I wrote a piece highlighting and praising the land use development pattern of streetcar suburbs, which proliferated in American cities of all sizes roughly between 1890-1930. The positives I noted about the pattern include its adaptability, as the pattern has been able to be successful even as the streetcars that supported them have disappeared, and its efficiency, as it accommodates, in a very orderly fashion, ranges of residential and commercial uses. I’ll show that below.
But first, let me clarify a couple of things. My preference for the streetcar suburb is rooted in its land use design, and should not be taken as a public transit call to arms. I like public transit, make frequent use of public transit, and believe public transit should play a big role in the development of metropolitan areas. But some comments I’ve received thus far assume that I’m advocating for bringing back the streetcar as well as the land use design, and that’s not necessarily the case. In fact, what I like about the design is that it is still fully functional long after the streetcar line tracks have been pulled up. Places like Birmingham, MI, outside of Detroit, do well despite losing the streetcar long ago. Some may argue that economics has more to do with that than land use design, but I maintain design is a significant factor.
Below are some streetcar suburb design examples I’ve put together to illustrate the design’s adaptability and efficiency. The examples assume a pretty strict grid orientation, but as I noted earlier, such a grid orientation is not necessary. Following the illustrations are land use data tables that provide a sense of the kinds of residential densities that can be achieved without the construction of a total high-rise environment.
As you look at the designs and the data tables, remember that there are essentially three principles that inform the designs:
- Concentrate commercial development at the intersections of arterial roadways. In this instance, I’m assuming the roads at the edges of the designs to be arterial roadways that carry larger amounts of traffic.
- Include mixed uses and multifamily uses along the interior parts of arterial roadways, and on collector streets. One problem with today’s suburban development is the overabundance of commercial land as suburban municipalities try to game each other for commercial sales tax and property tax revenue. Most communities can’t support the commercial development they try to attract; mixed uses and multifamily uses can be a more feasible option.
- Keep single family uses within the center of design sections, buffered from the edges by more intense uses. I know part of the appeal of single family homes is the sense of separation from undesirable uses like multifamily or commercial uses. However, I think most people attracted to single family homes will live with those uses as long as they are not immediately next to them, and will abide by more intense uses as long as their refuge area is maintained. This design scheme allows for that.
On to the designs. You can click on any graphic to make it bigger.
This graphic represents a low density streetcar suburb design for a one square mile area. For those unfamiliar with traditional “land use colors”:
Yellow – single family home blocks
Pink – mixed use development blocks
Green – parks/green space
Blue – public/institutional uses (schools, churches, etc.)
Gray – roadways
Subsequent graphics will include two additional land use types not shown here — orange (multifamily uses) and red (commercial uses).
And here’s the data table that goes with it:
Assuming roads with a 66′ right-of-way for streets, a 66′ x 124′ typical single family lot and a even a 16 ‘ public alley between blocks, the design is able to achieve a pretty reasonable residential density of almost four units per acre despite the facts that more than three-quarters of the homes are single family homes. On a net basis, the single family homes come in at five units per acre, and the mixed use areas at the corners of the design come in at 13 units per acre. Overall, assuming some reasonable household sizes, this design could accommodate more than 7,000 people per square mile.
Here’s the medium density design:
And the medium density design data table:
Here, I removed some of the single family blocks to include multifamily uses near commercial uses and mixed uses, and filling in multifamily uses on arterial roadways. Doing that shifts the proportion of unit types substantially (single family homes now are 45 percent of all units, and multifamily and mixed use units are 55 percent), but it does so without altering the character of the single family blocks that remain. Single family lots are slightly smaller (54′ x 124′). Overall, the units per acre jumps to 6.7, and the gross density of the design jumps to more than 10,000 people per square mile.
Here is also a good place for me to elaborate on exactly the kind of multifamily development I envision in this design scheme. Notice that, in the data tables, I never call for more than four units per standard lot in any design scenario. That necessarily enforces a “missing middle” multifamily design of townhouses, duplexes, four-unit buildings and courtyard buildings that look much more like this:
Which can easily fit into the fabric of a community that has a strong single family orientation without compromising its design integrity. Such multifamily designs can also stand on their own in larger multifamily subcommunities.
And now the high density design:
And the data:
Here, single family lot widths are reduced to (an admittedly narrow) 33′ x 124′, and multifamily blocks line the arterial and collector roadways of the square mile site. Doing this causes the units per acre count to rise to nearly 13, and a gross density that exceeds 14,000 people per square mile.
Put it all together and what do you get?
Here I put together four square-mile designs (two low density and one each of the medium and high density) to see how it might look. I re-oriented the commercial and mixed uses in the medium density section (the upper right) to create a commercial core at the center of the larger area.
Here’s the data:
Overall, you end up with a community that is efficient in its design, dense but not overwhelmingly so. This area could potentially house as many as 41,000 people in its mix of single family and multifamily units, giving it a mix that is rarely achieved in most American cities and suburbs. As a four-square-mile area with nearly seven residential units per acre, it is able to be adequately served by public transit. The 40/60 single family/multifamily unit split means that there should be units available in the area, making it affordable to a broader range of residents. The concentration of mixed uses and multifamily uses near the commercial center means there is a ready and sizable market nearby to support retail and services. Even as there are vibrant areas that would rely on pedestrian traffic, there are nearby single family enclaves that can be refuges to those who want space, peace and quiet.
I understand the critiques that may come from people regarding these schemes. Those who know Chicago very well may see the city in these designs; I admit that. Others may say that the strong grid orientation isn’t feasible everywhere, and that’s true, too. Still others will say that the methodical implementation of the design is boring; I can’t disagree with that, either, if it’s implemented without ways to break up the grid in interesting ways.
Ultimately, I’d say that communities should consider the three principles mentioned at the outset as community retrofitting, particularly suburban retrofitting, starts to happen throughout the nation. Create commercial centers, don’t be afraid of mixed uses and multifamily uses, and set aside buffered single family enclaves for those who want them. Do that, and we vastly improve the quality of our built environment.