Part of the trouble is that street markings do not reflect car traffic or other special circumstances. In NW Seattle, for example, Fremont Ave (Blue or "least safe") is one of the best north/south corridors, because car traffic is light and supposedly has to turn at every major cross street. Bikes ride in the lane of traffic, reducing unsafe passing.
In comparison, Greenwood Ave (rated Orange, or "ok") has much higher car traffic and the painted bike lane runs in a door zone.
Anyway, Seattle doesn't really have any "green" bike infrastructure. If it did, this kind of map might be a lot more useful. In Seattle, I have to choose between "blue" or "orange." My highest priorities for bike safe routes include low car traffic and no door-zone bike lanes, and the separate painted lane is less important.
It seems that a lot of the time, painted lanes are added to the busiest streets. Especially on the eastside, I wouldn't suggest riding on any of the marked routes on Mapzen.
That's my go-to reference when looking for new routes. We can really think of its reliability as a signal-to-noise ratio: inexperienced road cyclists might cause the map to show significant traffic on bad roads while experienced cyclists choose good roads. There are presumably fewer cyclists entering the realm of road cycling than there are experienced road cyclists. The new road cyclists are likely aware of the dangers of the sport, so in most cases, they probably seek resources for planning rides (e.g., cycling groups).
That brings up another point: Group rides will generally use good roads, and there will be multiple cyclists simultaneously contributing to the same route on the heat map. The boldest paths on the heat map may then very possibly be routes ridden by group rides, suggesting they're very safe.
More experienced cyclists might be more likely to own and use GPS units as well. Strava's heatmap only has data from users that self-report GPS traces.
> Part of the trouble is that street markings do not reflect car traffic or other special circumstances.
I absolutely agree. I bike almost daily in Brooklyn, and the information I glean from maps like this (or the official NYC bike map) is only a small part of what I consider when selecting a route. Having experience with the nature of car and truck traffic in a given neighborhood is an order of magnitude more valuable than information about bike lanes.
Cyclist safety is a tough issue. From an infrastructure perspective, creating safe bike lanes is a hell of a lot more difficult than simply painting lines on a street. I wonder what ways tech can help cyclists make safe choices beyond maps.
I had to RTFM to figure out what the yellow highlights are. Those are roads that have been designated as part of a biking road network. In your example Fremont should presumably be highlighted yellow. I think the renderer puts far too little visual emphasis on the bike network roads (and omits the markings from the key!)
Since it is open street maps, it relies on manual curation. My guess is that some curators use the official city bike maps, and others editorialize.
This seems to do a great job where I am, though it crashes repeatedly on both iOS devices I tried. It definitely needs better testing with mobile safari (and an app with some sort of tile caching / offline mode, unless I'm missing something)
> I had to RTFM to figure out what the yellow highlights are.
Yeah, I was confused at first too. It is mentioned lower down in the article.
> In your example Fremont should presumably be highlighted yellow. I think the renderer puts far too little visual emphasis on the bike network roads (and omits the markings from the key!)
Yeah, although the Seattle yellow highlights are missing a lot (e.g. the Westlake cycletrack, which is one of the few "green" corridors in the city and used by tons of cycle commuters, isn't highlighted). The Elliot Bay trail, another "green" corridor along the bay, is highlighted around the interbay area but not the portion that heads into downtown. The Interurban North multi-use path is also missing from the highlight. But that's just bad data; it can be fixed.
Edit: Oh wow. It turns out some highlighting isn't shown at some zoom levels. (In particular, the zoomed out view I would use to try and plan a route is missing some highlighted segments that show up at higher zoom.) I saw a random block highlighted yellow; zoomed in and it is part of a much longer segment. That is a big UI problem.
The preferred styling is OpenStreetMap. One word, no sss.
Part of what loeg is saying is that the dedicated bike infrastructure they have is not especially bike friendly. To the extent people are following OpenStreetMap's "on the ground" rule, it will be hard to extract information about that from OSM.
Here the main highways are US Bike Routes, which means they get highlighted on the Mapzen style, with the exception of someone doing a through trip (where they are the logical route), they are the absolute worst places to cycle in town.
Worse, "adjacent bike lane" can in practice mean anything from "safe-to-use lane" to "extra-wide parking lane with those weird pictures". From my experience, shared lanes run an even wider gamut from "shared with 0 cars a minute" to "shared with over 9000 cars a minute" ;)
We thought a lot about the colors for the new bike map. Green is pretty universal for trails and paths where bicycles are protected from cars. But colors are less standardized for places where bicycles share the road with cars – bike lanes, streets with "sharrows", and signed bike routes.
For this first version of the bike map we focused on creating a "warm" map that complements the basemap and invites the reader to spring into exploring the bike-friendly ways tagged in OpenStreetMap, the community mapping wiki.
While red draws the eye and is a warning color, we found that it overwhelmed the map in most cities when used for the least safe routes. If you want to experiment with colors, you can do so in Tangram! Instructions are at the bottom of the post. Please let us know what you come up with.
While OpenStreetMap's tags are a great starting point, they aren't a perfect proxy for safety. We're working on ways to effectively mark greenways, green waves (timed lights), `living streets`, or even buffered bike lanes.
Seattle is quite well tagged in this regard, and we're working to improve San Francisco. What will help most is tagging important streets into a `route relation` in OpenStreetMap (and of course getting your city and state government to build more protected bike lanes and neighbourhood bike routes).
This map is a first step, and your feedback will help make the next version even better. Thanks!
Color scheme is very strange though. I live in SF, and I imagine if you surveyed folks on the street, everyone would tell you blue is a "safer" color than orange.
Maybe it could follow the Google Maps standard—green, yellow, red (traffic)? They may be depicting a different metric more important to cyclists (safety), but the problem-solving approach is the same: try to take green / yellow routes and avoid red ones.
Part of the trouble is that street markings do not reflect car traffic or other special circumstances. In NW Seattle, for example, Fremont Ave (Blue or "least safe") is one of the best north/south corridors, because car traffic is light and supposedly has to turn at every major cross street. Bikes ride in the lane of traffic, reducing unsafe passing.
In comparison, Greenwood Ave (rated Orange, or "ok") has much higher car traffic and the painted bike lane runs in a door zone.
Anyway, Seattle doesn't really have any "green" bike infrastructure. If it did, this kind of map might be a lot more useful. In Seattle, I have to choose between "blue" or "orange." My highest priorities for bike safe routes include low car traffic and no door-zone bike lanes, and the separate painted lane is less important.
It seems that a lot of the time, painted lanes are added to the busiest streets. Especially on the eastside, I wouldn't suggest riding on any of the marked routes on Mapzen.