Why are you mapping sidewalks as separate paths, rather than as tags on roadways?

While sidewalks as tags are adequate for many applications, they lack the ability to add detail to crossings and curbs. This information is vital for people who use visual and/or mobility aids. There is a project called OpenSidewalks which aims to bring equity to pedestrian data and provide routing tools for people whom have more specific mobility needs than what traditional routing tools can accommodate. Here is an excerpt from their mission:

Pedestrian pathways are critical infrastructure in urban environments that help people engage in their professional, community, and daily lives. To promote equitable urban growth, transit-oriented development, and resilient communities, we must give strategic, pedestrian-centric consideration to our sidewalks and pedestrian pathways, which are the dynamic connective tissue of our physical environments. Individuals experience the built environment in innumerable ways depending upon many factors, including their mobility. Therefore, their optimal path through the built environment is not necessarily the shortest or most direct route (despite the inherent Google Maps bias). Rather, their travel experience is influenced by static physical features, e.g., the availability of curb ramps and auditory signaling at crosswalks, as well as transient conditions (like precipitation). Automated routing applications can also make great use of this kind of data. For example, provided with such information, individuals prone to slipping on wet terrain could circumvent cobblestone sidewalk surfaces on rainy days, and individuals who require curb ramps can selectively identify routes that can accommodate their needs.

Additionally, much of Montréal already had sidewalks mapped as separate ways, and I am just expanding that coverage.

Guidelines

Sidewalks

Sidewalks should be:

• Drawn in the middle of the physical sidewalk as it appears on satellite imagery,
• Named with the name of the street that they are a part of,
• Tagged with their material, typically concrete.

Here I have drawn a basic sidewalk and tagged it with highway:footway and footway:sidewalk by choosing this option for the line in the iD editor:

I then tag the sidewalk with the name of the street it runs alongside, and its surface material:

The name is important for routing applications, which will otherwise say things like “turn right onto unnamed footpath.” The surface can be left blank if you don’t know, since it can be added later via StreetComplete.

If your sidewalk crosses any other highways such as alleys or driveway, you may see a warning like this:

Which brings us to…

Driveway/Alley Crossings

A crossing way should be drawn whenever a sidewalk crosses a:

• School driveway
• Alley (except for ruelles vertes, which can only be used by pedestrians and cyclists,)
• Commercial access road or driveway
• Residential driveway serving more than 5 units

Essentially, whenever a crossing has a high likelihood of encountering vehicle traffic. If your sidewalk is crossing something lower volume than this, such as a driveway for a single home, you can simply click “Connect using a crossing” now.

For the higher-volume crossings, we need to add a crossing segment. To add a crossing segment to a sidewalk, double click the sidewalk way where it connects to the driveway it is crossing to create a node. Then right-click that node and click the scissors icon, or press X to split the way at that node:

Repeat this on the other side, so that you have a section of the sidewalk as wide as the driveway that is separated from the rest. Select this section so that we can modify its tags.

Now change the way’s type by clicking its current feature type of “Sidewalk” in the left sidebar, and choose Unmarked Crossing.

You may now click “Connect using a crossing” in the Issues box, which will add the appropriate crossing node to the point where the lines connect. No curbs need to be added to the nodes where sidewalk and crossing connect.

Why do it precisely this way? I have noted a few benefits:

• Sidewalks and their crossings remain much straighter than if you drew each section individually.
• The name and surface type only need to be added once, rather than once per section.
• Adding the crossing via the Issues box before changing the way type to Crossing results in doubled questions in StreetComplete, and it also adds curbs for no reason. This results in the fewest unnecessary StreetComplete questions.

Intersection Crossings

There are three kinds of crossings:

• Unmarked, for when there are no lines on the road and the crossing is uncontrolled,
• Marked, for when there are lines on the road and the crossing is uncontrolled,
• With Pedestrian Signals, for when the crossing is controlled by a traffic light.

Crossings where one has to step down from the sidewalk and traverse the road should end in Curb nodes, to indicate to routing software that this is necessary. The curb nodes should not be directly connected to the sidewalk ways themselves, because this would wrongly signal to routing software that it is necessary to navigate a curb in order to continue along the sidewalk.

Here is an example of a completed intersection with sidewalks, footpaths, and crossings:

Note how the top two corners have two curb nodes, to denote the different curb heights and exit points. This is atypical — most sidewalks have only one lowered curb that grants access to the crossings in both directions, like the bottom two corners in the picture.

Note also how the sidewalks do not directly connect to the curb node and are instead attached via a Footpath. This is to avoid routing software thinking that a curb needs to be navigated when one rounds the corner on the sidewalks.

Most detail for intersections is filled in via StreetComplete, including curb height, tactile paving, and details about controlled crossing lights. One important note about the question regarding tactile paving on sidewalks: it is not asking if there is tactile paving on either end, ie. at the curb, but rather if there is tactile paving along each side of the crossing, helping visually-impaired pedestrians to stay within the lines. This is very, very rare in Montréal and can almost always be answered “no.”

Finishing Up

Once you have drawn in the sidewalks, you’ll need to go back and remove the tags from the roads that denote sidewalks being there. The easiest way to do this is with the StreetComplete sidewalk overlay. Open up StreetComplete and open the menu, then select “Overlays”

Select the “Sidewalks” option.

You’ll see the map change, highlighting sidewalks in blue. Anywhere where there is both our separate sidewalks and a blue border on the road, we have to edit. Tap a road, and it will bring up a menu showing its sidewalk tags:

Tap each side where it shows a sidewalk, and change it to “Sidewalk, but displayed separately.”

After you upload your changes, the sidewalks will no longer be duplicated.