On-site vs off-site parking and a Swedish model for suburbs
|Driveways and abundant on-street parking help bring parking spots as close as possible to housing|
|Low-rise multi-family housing surrounded by parking|
|Typical North American mall, surrounded by acres of parking|
A theoretical demonstration
So how much impact does parking location convenience has?
Well, first, let’s take a typical case of on-site parking with every house having a parking on the lot, in the form of a driveway. Houses are on side streets, so drivers go down to the arterial road then drive to the destination, either an office, industry or a store, which also has parking on-site. Schematically, this is what it looks like:
|In yellow, the trip using cars, in blue, the trip using transit, dotted sections are done on foot, bus stops are the blue dots|
So, in this case, the time wasted on car trips is minimized, with parking very near doors of homes and destinations. All in all, car trips include only 1 or 2 minutes of walking. Meanwhile, walking to the bus stop may take 3 to 5 minutes (an optimistic figure), waiting at the stop can also take 3 to 5 minutes (supposing the transit user knows the schedule and goes there just to get a bus), and the bus stop at destination is still far from the door of the destination, so that’s another 2 to 3 minutes. All in all, the transit trip includes around 10 minutes of walking and waiting, and that’s if there is no transfer.
So, if we do a mode race to see how much time it takes to reach the destination on foot, on a bike, on a car or on a bus, we’d get something like this:
|Mode race of the case with on-site parking, cars have a massive advantage|
In this case, a 5-km trip (roughly 3 miles) would take nearly 25 minutes on transit, but only 10 minutes in a car. Cars start with a 10-minute advantage over transit and only increase that advantage over longer trips thanks to their higher speed.
Now let’s take the exact opposite case, where both residential and commercial/office parking are off-site. In this case, car drivers have to walk 2-3 minutes to their car from their home and 2-3 minutes from the parking to their destination. Bus riders still have to walk the same distance to their stop, but as there is no parking in front of the destination, they will save quite some time walking to their destination from the bus stop at which they alight.
|Schematic representation of the case with off-site residential and destination parking, car drivers have to walk much more in this case, even more than transit users|
|Trip distance vs time for the off-site parking example, here, cars lose most of their advantage for shorter trips|
In this case, the same 5-km trip as before would take about 16 minutes in a car and 21 minutes on transit. The difference is much reduced and allows transit to be much more competitive. Bikes also shine here, as bikes are easily portable and offer something much closer to a door-to-door trip.
Finally, there is the on-street parking scenario, which is in the middle. If there is plenty of parking spots on the street, the results are very close to the first case with on-site parking. If there is a shortage of parking spots, then people may need to walk a bit, approximating the off-site parking example. In both cases, if parking is on-street, then destinations tend to be built next to the sidewalk, reducing walking distances for transit users.
The Swedish model
OK, so what got me thinking about this is exploring Swedish cities through Google Maps, trying to get a sense of their organization. Many neighborhoods of Swedish cities have a particular form. Sweden cities have very strong planning, and the Swedes often live in multi-family housing, 40% of them do, many of them inside apartments built by a government program, the Million programme, under which the government motivated the construction of one million dwelling units in 10 years, a massive undertaking in a country of 8 million people.
Anyway, many multi-family neighborhoods in Sweden have a peculiar form in modern developments, take a look at this area from Vaxjo:
|Residential area in Vaxjo, Sweden|
Let me identify the parts of that area:
|Distinct subsections of the neighborhood|
What we have here is a strictly segregated approach, with a vast residential area without streets for vehicles, where buildings are linked by footpaths and bike paths. The road connecting this development to the rest of the city only runs on the periphery, and between the road and the residential area: parking lots. That way, cars are strictly kept out of residential areas where people walk and bike, total use separation. It also means that cars are left near the road, which can be nearly 200 meters away on foot (700 feet)… right next to the bus stops. This also leaves plenty of trees and greenery in the residential area. Make no mistake, this isn’t really urban, this is clearly a suburban area, but one where taking transit is not penalized versus using a car.
Technically, I guess the parking is still on-site. as it seems clear this whole area is one big development project, but for all practical purposes, the parking is effectively off-site due to its distance from residential areas.
Here is a particularly striking example (at least, from the sky), from Norkoping, a concentric neighborhood with parking on the outside ring, then two rings of apartment blocs, all surrounding a park:
|Concentric neighborhood in Norkoping|
Here is another example in Karlstad:
|Suburban neighborhood in Karlstad, Sweden, with the neighborhood’s commercial area identified, as well as the main footpath/bike path|
This particular instance is interesting because there are very few roads for cars through this area, in fact, using Google Maps to give me walking and driving trips from one apartment bloc to the commercial area yielded me the following:
|Walking trip from an apartment bloc to the neighborhood commercial sector, time of trip: 4 or 5 minutes|
|And here is the directions for the shortest car trip, note the time: 5 minutes, about the same as walking, so you would save no time by driving instead of walking|
Another advantage of this design is that since there is only one main road, it concentrates transit users on one bus route that travels along that road. As a result, the bus line is frequent, data available online shows that the bus that does the loop actually has an headway of 10 minutes off-peak, in a city with a population of 87 000 people.
This total separation of motorized vehicles from pedestrians and cyclists may also be partly responsible for Sweden’s excellent traffic safety results. Indeed, Sweden is in the Top 5 safest countries on Earth both by traffic deaths per 100 000 people and by 100 000 cars.
Again, make no mistake, this is a suburban area, but a suburban area that seems to focus more on walking, biking and transit than on cars. Not to say that Swedish cities are only made of such neighborhoods, not at all. They have plenty of traditional Euro-blocs in older areas and single-family areas with driveways in front of every house:
|Single-family houses in Stockholm|
In some instances, they even use elevated parking structures on the periphery of residential areas:
|Elevated parking structure in the center of the image, to absorb the parking demand for the high-density housing without overwhelming the residential area with cars, in Stockholm|
The use of elevated structures is particularly interesting, because it is one way to really build a lot of parking on a very small lot, without breaking the bank. It can serve the purpose of hiding cars from view and preserving more of the lots for pedestrian-friendly amenities or design.
This type of neighborhood design is more typical of multi-family housing, but some single-family housing also use parking lots and garages put at the periphery, leaving the inside of the neighborhood free from cars:
|Single-family area with parking lots put at the periphery, in Lund|
|Image of one of the parking lots, in fact, parking garages, that would typically be built adjacent to houses but that are instead grouped in the same location|
|Images of the houses with footpaths separating the houses|
Of course, that design of self-contained neighborhoods with limited roads is great for transit, but it offers relatively poor connections between neighborhoods for pedestrians, often with paths that are not in view of residential areas. It also lacks mixing of uses as commercial areas tend to be put in a different location from residential. Still, Swedish cities do a lot of effort to build bike networks, often allowing faster, more direct paths to cyclists than cars. As a result, despite the quantity of greenery of Swedish cities, bike and transit mode shares are very high (bikes more for smaller cities, transit for bigger cities). All data here from TEMS.
|Mode share in Stocckholm, the biggest city of Sweden (metro population of 2 millions), extremely high public transit usage, relatively low active mode shares|
|Mode share in Gothenburg, Sweden’s second largest city (about 500 000 people)|
|Mode share for Linkoping, a city of 140 000, there we see bikes being much more used, with still a significant amount of public transit use|
|Mode share for Lund, population of about 100 000. To compare, transit mode share in Toronto and Montréal is about 20%, so 16% in a 100 000-people city is quite high|
|Mode share for Uppsala, pop. 140 000|
The advantages of off-site parking
I think this model showcases how useful off-site parking lots can be, especially for a transition from suburbs to more sustainable, walkable cities. One of the big problems of density in suburban areas is that it results in cars taking over the public sphere entirely, being everywhere. The Swedish approach of putting cars in their own little zone apart from residential areas can help make it more palatable to live in such an area. Like a shameful disease, cars are best kept out of view of the community, allowing for more human-friendly design to dominate the public realm. The inconvenience of the parking location also encourages other modes of transport by reducing the time advantage of cars.
Off-site parking could also have an additional advantage of being possibly adaptive to demand rather than simply being regulatory. When parking is required on-site, since unused spaces on one lot cannot be used by residents of another, every lot is obliged to provide enough parking for its residents’ highest possible parking demand. Off-site parking could allow for parking spots to be attributed to those who need them, so less of them would be needed, because residents not using their “allotment” could simply sell the spaces or stop renting them, allowing someone else to use that space. If parking spaces get rare, a new parking lot could be built. So off-site parking lots could theoretically do away with the need of minimum parking requirements.
For example, let’s take the typical example of houses which regulation says needs to have 2 parking spots, built on-site. The regulation being what it is, the parking spots are privately owned by whomever owns the housing, and the price for the parking is bundled with the house’s price. But since the regulation is there to make sure that enough parking is provided, in fact, it may well be that a significant amount of parking is not actually in use by a car.
|Schematic example of houses with on-site parking spots, in light blue, ones not regularly used by vehicles, in dark, spaces that are regularly used|
Now, in this situation, with 14 units and 28 parking spots, fully 10 parking spots are unused, but they cannot be used because they are privately owned. So even if you want to add other units, you cannot tap into the unused parking spots to avoid having to fulfill the parking requirements, because these parking spots are off-limit.
On the other hand, if you have another approach, where the 28 parking spots have been put in one parking lot, with homeowners having the choice to separately buy parking spots, then you have the following:
|Schematic example of houses with off-site parking spots|
In this case, because the 10 unused spots are still available for purchase, you could theoretically allow 5 new houses to be built without adding additional parking, because there still is 2 free parking spots for each of these newly built houses. And since people have to pay for their parking separately, it makes it more worthwhile to opt out of having a car. If you’re flexible enough, you could also allow for parking lots to be sold to be developed if they’re not used enough, which would make cars have to compete with housing for the land.
To be fair, this can also be done with on-street parking, but I think I’ve made it clear that I disliked that solution, as cars parked on a street claim it for cars and clutter up urban areas. As the city is typically responsible for building and maintaining streets, reliance on on-street parking also makes public authorities responsible for providing parking for residents, opening the door to all sorts of conflicts as the city is then forced to manage parking and held accountable if there are parking problems. I find it much better to leave parking in the hands of private residents and businesses, so that the costs can be borne by those who use it, not by the community at large.
So anyway, the more I think about it, the more I think this is a way of tackling parking that could be promising. This is also valid for commercial parking lots. This approach is scalable, it could work in suburbs, where low land prices and density could at first lead to affordable parking, but also allow for a gradual reduction of the amount of parking as land prices increase due to development and better public transit options slowly make car use less important. In other words, I think it could be a complementary approach to incremental developments.