Wednesday, August 13, 2014

Streetcar suburbs: how they were designed and what we can learn from them

When we talk of "suburbs", the first  thought that comes to mind is the typical sprawl development of single-family homes with use separation, with jobs segregated in industrial parks and shops in strip malls surrounded by lots of parking. A bit like this:
"Typical" suburb
In many ways, "suburbs" has become synonymous in North America with "sprawl". It's implied that this is an area that is car-dependent, where getting around any other way is hard, if not downright impossible.

Yet, that wasn't always the case. "Suburb" just means a built area that is close to an urban one and which is dependent on that center. Nothing forces suburbs to actually be car-dependent sprawl. In fact, the first suburbs of the late 19th century, early 20th century were quite different.

Streetcar suburbs: the first and most successful TOD

"Streetcar suburb" is the name reserved for the suburbs built in the late 19th century, early 20th century around streetcar lines. The streetcar lines were the main connection between these suburbs and the urban area they were attached to. Sometimes, the streetcar companies were deeply involved in the construction of the suburbs themselves, they would buy land that had little value on the outskirts of cities, then build a streetcar line through them. The streetcar would highly increase the desirability of the area and increase the value of the land. The streetcar company would then either divide the land and sell the lots at much higher prices than they paid or build the real estate themselves and sell or rent it.

This is what is called "value capture" and it was a major way streetcar and rail companies would fund themselves in the "old days". Many of these companies would actually be created by real estate giants, just to feed their main estate activities. Electricity companies would also be involved, resulting in huge companies that had many activities feeding each other, the very definition of synergy. Estate companies would build streetcar lines to build more real estate around them, they'd build power plants later on to run electric streetcars and sell the excess electricity to consumers. When antitrust regulations broke up these huge synergistic conglomerates, streetcar lines, that had been subsidized to feed value onto real estate activities, would struggle to survive, especially as fares were kept low by political pressure.

Anyway, the design of streetcar suburbs should be of high interest to anyone interested in TOD today, because these were some of the best transit-oriented development cases in history.  The resulting neighborhoods were highly walkable and had high density (but not as high as earlier urban cores) and often still had places for greenery and parks. Though streetcar lines are gone, many of these still remain highly desirable locations in North American cities and their design still favors walking and transit over cars... unless they have been "urban renewed" into oblivion.

Example of streetcar suburb: Plateau-Mont-Royal

The Plateau-Mont-Royal is a borough in Montréal which is often referred to as the crown jewel of urbanism of Montréal and/or an haven of dirty hippies anti-car crusaders, depending on whom you ask. 
Plateau Mont-Royal
 Some key data:
  • Population: a bit over 100 000 people
  • Land area: 8,1 square kilometers (3,2 square miles)
  • Population density: 12 000 people per square kilometer, 31 000 per square mile (though in residential areas, it can get as high as 20 000 people per square kilometer, around 50 000 per square mile)
  • Mode share overall: Car 34%, transit 28%, active transport (walking and biking) 38%
  • Internal trip mode share (for trips inside the Plateau itself): Car 23%, transit 6%, active transport 71%
A commercial arterial of the Plateau in winter
Residential street of the Plateau, full of multiplexes
Plateau seen from the air
This neighborhood was essentially all built after streetcar lines came in the early 20th century, and there were quite a few of them.
Streetcar lines of the Plateau-Mont-Royal borough at their peak
But what's important is more than just the density or the presence of transit lines. The design of the neighborhood reveals what is, I believe, the foundation of good, strong TOD development.

All trips tend to be made of two locations, an origin and a destination. Though one can certainly point out how an A->B trip tends to be balanced by a B->A trip and that A and B are both respectively origins and destinations, I think in reality, that's not quite correct. The origin of trips is generally people's homes, where they live. The destinations are where they go to do certain activities, be it working, shopping or any other activity worth moving for.

A lot of times, when TODs are discussed, people simply think of high density housing around transit stops, but I think the Plateau reveals something about the ideal location of residential areas (origins) and stores, restaurants, workplaces, etc... (destinations).

Streetcar lines superposed on a Google Maps search for "stores"
In the previous image, I searched for "stores" on Google Maps, which is able to give us an interesting insight about where stores are mainly located in relation to the streetcar lines. Note how they superpose almost perfectly. Indeed, streetcar lines were not located next to high-density residential areas, but next to stores and restaurants, with high-density housing a bit further out.

This makes a lot of sense as destinations, stores, workplaces, etc... generate more trips per square foot than housing does, so by putting them next to transit lines, you optimize the urban design to reduce distances for the most amount of people. People just need to walk to the transit line, then they can reach their destinations with minimal walking after they get off the vehicle. It also reduces traffic and activities in residential areas, preserving calm and tranquility in areas away from the main streets.

The Avenue Mont-Royal street is probably the most efficient design. Blocs in the areas are elongated rectangles rather than squares, and around the Avenue Mont-Royal, the elongated blocs' longer sides are perpendicular to the  streetcar line. What it means is that there is no detour required for pedestrians, the commercial avenue is right down the street, wherever they live in the neighborhood.
Avenue Mont-Royal, the red line is the old streetcar line, the orange area is commercial, the green is residential

A schematic view of the previous, with arrows showing direct access without detour to the commercial avenue
Now this design is great for pedestrians, but horrible for cars, because it results in an enormous amount of intersections, stops and traffic lights on the commercial avenue itself. When streetcars reigned, there was little to no traffic on the side streets, so they could go quickly down the avenue regardless of the intersections, but when cars became the major mode of transport, the design imposed was quite different, as it became important to reduce the number of intersections on the main commercial arterial.

Now let's look at a car-oriented commercial boulevard design in contrast:
Car-oriented boulevard Taschereau in Longueuil, notice the detours required of a pedestrian from point A to reach a destination on the boulevard and the few intersections on it.
The street grid of this area results in few intersections on the main street, but also in detours required for residents in the area to get to it. The objective is to speed traffic on the boulevard and also to avoid traffic on residential streets (though if streets were in a grid, the traffic would be fragmented and not be bad on any street as there are many alternatives to get to the main street). This design is all about favoring vehicular speed even if it increases distances.

What lessons to remember about streetcar suburbs

It is vital to take from this successful TOD design that housing, no matter how dense, shouldn't have the priority of the area around transit stations or stops. Priority should be given to commercial areas and to workplaces, with high-density housing a bit further out, but still within walking distance. This maximizes the efficiency of transit by increasing the number of trips that can start and end very close to transit stops since commercial areas and workplaces generate a lot more trips per square foot of floor area than homes. For instance, there may be 1 person per 40 to 50 square meters in homes (400 to 500 square feet), but in workplaces, it's not rare to have one worker per 8 or 9 square meters of floor space in office (80 to 90 square feet) if not less in open office designs. That's 5 or 6 times as many people for a same floor area, and thus likely up to 5 or 6 times as many trips.

An highly porous street grid is also a good complement to transit lines as it reduces distances to reach the line and commercial areas. This reduces the need for feeder lines and makes active trips (walking, biking) complementary with the transit lines. No one wants to be taking a bus or streetcar to get a carton of milk. Commercial and residential areas therefore need to be close together, you don't even need to technically "mix" them, you can have use segregation and still have an efficient neighborhood, as long as the uses are close to each other.

Can we replicate streetcar suburbs today?

The coming of the car has changed transit a lot. One of the reasons why streetcars failed in the end (and why mixed traffic transit as a whole struggles in modern cities) was that cars and mass motorization would create congestion on streets even far from downtown. It would also lead to traffic lights and stops, all of which slowed down streetcars significantly. Even as technology got better and streetcars got better acceleration and braking, the interference from cars and the traffic signals made the lines slower and slower, making transit less attractive to riders and more expensive to run. The slower transit is, the more vehicles and drivers you need to offer the same frequency, and thus capacity.

Not only that, but families are much smaller today, so there are less people per households than there used to be, reducing residential density. Most of the loss of population of cities since WWII is due to smaller households, not loss of housing. This means that distances traveled will likely be higher than in the past, even if the old neighborhoods remained intact.

Combine the reduced density and the slower speed of mixed traffic transit and it's clear that streetcar suburbs can't be built like they were in the past. The best bet now is in rapid transit (subways, trains on a separate grade from traffic) or semi-rapid transit (BRT and light rail on their own right-of-way but at-grade alongside pedestrian and vehicular traffic). These allow higher speeds to be reached, 30-40 km/h (20-26 mph) for rapid transit and 20 km/h (12-13 mph) for semi-rapid transit which can compensate for the lower density of modern cities. However, these forms of transit have less stops than old streetcars did, so it means that we need to compensate with much higher buildings and higher densities at the transit stops, since there are a lot less of them now.

Vertical streetcar suburbs

Another option is to create what I call "vertical streetcar suburb". What are they? Essentially, take the commercial buildings and the residential buildings on the side streets and rotate them 90 degrees to get the residential buildings over the commercial buildings.
Old-fashioned streetcar suburb

A vertical streetcar suburb with residential buildings flipped 90 degrees and put over commercial buildings
What is called "Vancouverism" would be the best example of a "vertical streetcar suburb", with commercial bases and high-rise residential areas over them.
Vancouverism: high-rise residential building standing on a commercial base flanking the street


  1. The examples are a lot more dense than what are usually referred to as streetcar suburbs in the US. Usually they're neighborhoods of small-lot single-family houses with a mix of duplexes and small apartments, with some larger apartments and stores/mixed use buildings along the main thoroughfare where the streetcar ran. Because they're less dense, you don't usually see a continuous commercial corridor along the streetcar route, but it tends to be a bit more nodal with business districts at important intersections and denser apartments in between. What I find interesting about it is that since density naturally wants to fall away the farther you walk from the streetcar line, it allows for a lot of variety in the built environment in a relatively short distance. It's not unlike the finger plan of Copenhagen, which although it's arranged around more of a rapid transit/electric commuter rail system, the space between the "fingers" of development along the rail line is much more rural in character with parks and preserves. Streetcar lines can do a similar thing, though on a bit smaller scale.

    Anyway, the design of the street grid is of paramount importance, regardless of the density. It's still the same pattern if you have multi-story commercial buildings along the streetcar line with dense apartments and row houses on the side streets, or small single-story shops along the streetcar line with single-family houses on the side streets. The connectivity and spinal nature of the streetcar line is what's important. Even neighborhoods that never had streetcars but were built in the 1930s and 40s can have this pattern, though I suspect they were laid out pre-Depression and just sat in limbo until the post-war period. Either way, maybe they figured buses would serve the same purpose, and that parking could be accommodated either on-street or in parking lots between the commercial buildings and the residential neighborhoods. They probably never foresaw just how tempting the new strip mall a mile or two out of town would be in luring those businesses or their customers away.

    1. Indeed, the Plateau is quite dense. I think I have already mentioned that it seems that Americans (and Canadians) tend to have a cultural aversion to multi-family housing which results in them building single-family homes even where higher densities might be useful (though some townhouse neighborhoods are extremely dense like in Philadelphia). Whereas in Québec, even old villages with a populations in the hundreds tend to have a reasonable amount of duplexes and other stratified multi-family housing in the center.

      I checked out old streetcar lines in Chicago, around Irving Park road and Montrose Road and the same basic design seems to be there, with side streets ending on a commercial avenue where the streetcar line used to run. Except instead of multiplexes like in the Plateau, the side streets were full of narrow and deep single-family homes (like in Toronto and Vancouver). Though the density was much lower, the design also reduced distances as much as possible to the commercial avenue (and the streetcar line).

      Some people criticize urbanists in favor of transit-oriented development of trying to deprive people of choice, but as you say, transit-oriented development indeed can preserve choice, with higher density along transit lines and lower density farther from them (but still within acceptable walking or biking distance).

  2. Chicago was somewhere in between Toronto and Philadelphia and Montreal in terms of density back in 1940/1950. The neighbourhoods like West Town, Old Town and the Lower West side were I think pre-streetcar, and with a significant and usually dominant multi-plex component. Lots were generally deeper, and buildings detached though, so densities were somewhat lower, but still denser than Toronto. The exception was the inner South Side where blacks were forced to crowd into. Although the built density was similar to West Town, Old Town or Lincoln Park the population density was higher, more like the Plateau if not a bit higher. Neighbourhoods further out had densities similar to Toronto but with more of a multi-plex component, such as Irving Park.

    I think an important point on the layout of streetcar suburbs is that the retail was along the streetcar line, so no matter where you were coming home from, you could stop at retail on the way home without increasing your travel distance.

    I think workplace densities aren't quite as high as you suggest, when you include board rooms, kitchens, corridors, etc I think 150-200sf/worker is more typical. Look at some big buildings like First Canadian Place or the former World Trade Centre and what was their worker population and square footage. A store might not have a worker density much higher than residential (I don't think 500 sf per worker would be unusual), however, a small shop with one worker could easily get 50 customers per day. You can probably get an idea of this by looking at the assumptions behind parking requirements for retail, and compare to the # of trips per day the average household makes (there should be stats on that too).

    I'm not sure changes in household sizes changes that much. They largely decreased because we got wealthier, so that means the average resident should be able to support more retail. And while population density has decreased, I'm not sure worker density has. A lot of the decrease was also related to fewer children, and also back then there were very few women that worked while today most do, which can basically make up for something like a 30% population loss in terms of the kind of job density a neighbourhood can support.

    You could have the highrise and retail be in a single building like a retail podium, or you could have no podium and just a straight up tower, similar to many of Manhattan's avenues, which would allow lowrise residential buildings on the side streets while maintaining the same density (Manhattan's streets are mostly lowrise or midrise). Or you could have something like with Yonge Street, where the commercial street has separate lowrise buildings (with a couple floors of office/residential above) and then highrises on the side streets. That can help make for a more diverse commercial street with smaller buildings and varied businesses.

    BTW do you think ROWs with frequent stop spacing can work more like the streetcars of old? For example the St Clair or Spadina streetcar ROWs? You should still have subways or other rapid transit too though, since cities have gotten more expansive than they were 100 years ago.

    1. You're right on workplace density, I checked it out and found figures between 150 and 250 square feet. That is still 2 to 3 times more than residential density, but not as high as I thought it would be. Retail does generate a lot more trips too because of the customers.

      There is data for this, the "Trip Generation Handbook" by the ITE provides the number of expected trips per floor area/employees/housing units based on empirical data. I do have access to it at work, but my professional conscience forbids me to use a workplace resource to feed a personal blog with data.

      I guess you could say that wealth and resultant lesser tolerance for crowding is the real reason for declining occupation rate per dwelling unit. I think it's a combination of factors, but the main point that is important to remember is that there are less people per unit than before. Lower residential density means that trips grow longer as residential areas are bigger for the same population and so people are on average farther from employment and retail centers. This greater distance commands faster means of transport.

      Reserving ROW for transit could very well maintain the functionality of such neighborhoods. However, it might never be the same because at the time of old streetcar suburb, streetcars were basically the fastest mode of transport. Nowadays, cars are faster. I think it would be possible to build new streetcar suburbs... if minimum parking requirements, minimum lot zoning and the like were waived for the area, and if the streetcar or even bus plugs into a rapid transit system (as you said, cities are more expansive than before, a surface transit line with an average speed of 15-20 km/h is just not going to cut it apart from some inner suburbs within 5-8 kilometers of downtown, people's tolerance for commute time is not limitless).

    2. This is perhaps getting a bit off-topic, but to do a streetcar suburb today you have to look beyond just the local zoning issues. The biggest problem I see is that of job sprawl, and by extension retail sprawl. A reason streetcar suburbs worked is because they connected the residential suburban areas with downtown. Yes businesses grew along the streetcar lines, but they were usually for serving those local areas almost exclusively. All the major jobs, shopping, and service activities happened downtown, while the businesses along the streetcar lines were secondary convenience type businesses, like the local restaurant, butcher, convenience store, etc.

      Such a pattern is similar to what you see along rapid transit lines and in a slightly more nodal form in commuter rail. The neighborhoods along the lines or around the stations are primarily residential with some local convenience type businesses, but the main economic engine is the big city downtown that all the routes converge at. This means you can have an effective transit system that's entirely radial, which is very easy to build, though unfortunately it's very unbalanced as far as time-of-day and directional running. The point is, since everyone for the most part is going to and from downtown, you don't need to worry about suburb-to-suburb trips because few people have any reason to make those sorts of trips.

      In today's paradigm however, downtown is usually just one of many employment centers, and may not even be the single largest one anymore. At the very least, even if still dominant, there's so many jobs dispersed throughout the rest of the metro area, that to properly serve them with transit you need a comprehensive net, more of a spider web than a radial arrangement. Chicago is a perfect example of a city with a radial transit network, at least when looking at the 'L' and Metra. The bus system is much more gridded within the city itself though. Anyway, that radial network is great if you're living in the suburbs (or residential neighborhoods within the city) and commuting to downtown, but nothing else. It's very hard to get decent transit ridership to suburban offices even if they're near transit lines because they can only effectively pull people from the particular route they're on. Anyone else from the rest of the system will have to take an "in and out" route through downtown which can easily quadruple the time it takes. Plus with little major shopping going on downtown but in suburban malls and strip centers, there's even fewer people using the radial transit network that would have in the past.

      A statistic that would be worth knowing is just how effective particular transit routes are at capturing the rides they actually serve. If you look at all of Chicagoland, transit ridership is pretty bad, in part because of massive job sprawl and suburb-to-suburb commuting. People can't take transit that doesn't go where they need to go, obviously. But I bet if you could find the transit ridership for suburb-to-downtown commuting it would be a much higher percentage.

  3. Thank you for posting this. If it's not too much to ask could you outline the typical placement of streetcar stops on image #7, #8, and #9?

    1. Actually, you can ignore that. Image #6 and #9 will suffice.