Even though mapping out safe routes can help, it's by far more a cultural and political problem that does not have technological solutions. You need separate bike lanes or completely separate bike paths, you need separate traffic lights for bikes. You need to change laws so that car drivers are always legally responsible for damage, even if a cyclist/pedestrian caused the accident (because it makes car drivers more careful/aware). You need to train car drivers to be more aware of cyclists, starting with simple things like knowing how to open a door carefully. You need a police force that conducts a deep investigation when a cyclist gets hit and a municipality that changes the layout of the roads to decrease the probability of it happening again. Etc.
I live in a country that is cycling walhalla, where there are more bikes than citizens, where a good chunk of the population go to work and do groceries by bike and we do all of the above.
There's a way to walhalla. Infrastructure, training, and liability laws prime the pump. When almost everyone is a cyclist, every driver knows that any cyclist could be a friend or family member. Or themselves.
Also... The Dutch reach. Open the driver's side door with the other hand to make sure you look for cyclists. In 12 years in Amsterdam I have never won the 'door prize'.
Honestly, the problem is, in most of the cities, people who drive almost never bike. If everyone biked, while driving, you would somewhat understand how the person on the bike reacts to their surroundings.
Tokyo is pretty sweet to bike around right now, despite the lack of dedicated bike lanes. It’s not as great as my times in Netherlands / Denmark, but it’s great nevertheless. It’s a bit weird, because almost everyone switches between roads and sidewalks, but you get used to it. For that, you need to make biking the superior mode of transportation for certain trips. With e-bikes, that is the case for a lot of activities within Tokyo.
Honestly, the problem is, in most of the cities, people who drive almost never bike.
That's true, but you have to bootstrap it. People will also not bike if it's not safe or attractive to do. In the city I live in, the city center was pretty unsafe for pedestrians and cyclists until the end of the 70s. Two persistent politicians decided to pretty much ban cars from the city center [1], which led to a lot of protests. They persisted and in 1977 the switch was flipped on a single day. Nowadays everyone here is in favor of this and other cities have made the same change, because people realize now that a city center without cars is much nicer: you can walk around much more carelessly, the air is cleaner, etc. Also, it made biking far more attractive, because you can get from the outskirts of the city to some shop much faster by bike than by car.
Since then, the cycling network has been continuously optimized to be able to travel between different points in the city as possible as quickly as possible and with as few interactions with cars as possible. And there are other amenities like traffic light that increase priority for cyclists when it is raining (to encourage people to cycle even when it is raining).
The same is true outside the cities, where there is a dense cycling network, largely separated from car roads. Both for fast work <-> home routing and for recreational cycling. The latter is the so-called fietsknooppunten network that prefers nice routes through nature, etc. over short routes [2].
Here's an underappreciated problem with biking in cities: storage. Most people in cities live above ground[0], and buildings don't have dedicated bike storage. Bike theft is common, and is a unique crime in being simultaneously highly disrupting to the victim, trivial to pull off, and not big enough monetarily for the police to bother pursuing - so you can't really park on the street overnight like you'd do with a car; it's too risky. This means people end up storing bikes in their apartments. Bikes are heavy and unwieldy and full of pointy bits and hard edges; going up and down with them is super annoying, especially if you don't have a lift (or it isn't big enough to fit a bike).
Solve the storage problem, and a lot more people city dwellers owning a bike will start using it daily, and many of those who don't will buy one.
--
[0] - Follows obviously from assuming most buildings have at least one floor.
All of this is just cultural cope. Bikes are stolen in Tokyo and Amsterdam as well. Tokyo space is incredibly limited. And etc.
The problem is, biking is just not efficient compared to other transport modes in super majority of the cities in NA. There is no political appetite either. People just love their cars, and can’t be bothered to restructure their lives like my friends in Paris did.
Automatic blaming of a driver is a horrific idea. Immediately unintended consequences spring to mind, cyclists purposely cycling into cars to get an insurance claim for one. This might sound far fetched but my friends in the UK police deal with pedestrians who throw themselves in front of slow moving vehicles in an attempt to get a damage claims.
I cycle to work, and I came here to ask if there's a crowd sourced city map that shows cyclist traffic accident black spots as part of my cycle route is genuinely frightening due to traffic.
This is the correct answer. One big problem is that your "safe bicycle path" can be made unsafe by a motorist that forgot to check for bicycles at any second. That can be parked cars, cars that turn right or or motorists that narrowly overtake with a high speed or whatever.
And the best solution for this is to create a separate space for bicycles that can't be accidentally violated without running into some sort of barrier. The next best thing is probably to include certain things in the the education for the drivers license that give people the empathy and perspective of what it feels like if you are on a bicycle and some asshole overtakes you with 70 km/h and half an arm of distance.
In my opinion the biggest problem is people who design roads/infrastructure don't bike. When they bike they will know what to do and how to pay attention.
So right now there is this huge push in EU to make more bike infrastructure. But people making it ... don't bike. At least not everywhere. And where they don't they will inevitably make bad bike infrastructure. This could just be corners that are too tight. Bad incline on a corner for example will not be obvious to someone who never bikes, could be just a few degrees. But on a bike it's deadly! Maybe not on dry asphalt, but bring some rain, sand, whatever and people will fall.
> Maybe not on dry asphalt, but bring some rain, sand, whatever and people will fall.
Oh man, here in Paris there's been a huge push for people to take up biking since Covid. But many bike paths are unbelievably stupid. Sure, many are too narrow, switch sides all the time, etc. I understand they had to do those in a hurry, it costs money to make them wider, etc.
But the most baffling thing is that some are actually painted with some slippery paint for some reason. I'm not talking about signs or delimiting lines, I'm talking about the underlying asphalt being fully painted, so that you're riding on the paint.
Bonus points for some of these particular paths going through a pretty pedestrian-dense area, and on the sidewalk, between parked cars on the left and pedestrians on the right who have to cross the bike path in order to reach the waiting area to cross the road. So you're very likely to have to emergency brake. I usually ride using the local bike sharing scheme, and even though those bikes are in questionable state, you're guaranteed to have the wheels skid when braking somewhat hard.
I was curious if the sensor would pick up other things like trees or other cyclist, but it seems like they accounted for that:
> We then log a sensor events [sic] if the majority of cells in the sensor frame agree to the same value within a threshold parameter [...]. This ensures that sensor events are only logged when large objects like cars block the sensor’s field-of-view , i.e., one or more small objects like branches or distance pedestrians in the sensor’s field-of-view will not trigger this condition. While there is no guarantee that this approach strictly identifies cars, we empirically saw during testing that passing cyclists and pedestrians rarely satisfied this condition at the typical passing distance due to the wide field-of-view of the VL53L8.
From the photos, there appears to be more than one sensor on the device which may be used to tell which direction the large object is coming from. Unless you were cycling backwards or mounted the device the wrong way around you shouldn't have any stationary cars passing you. Just a guess though.
I don’t know Seattle so I’d be curious to know if the proximity and accident hotspots are also high traffic zones in general, whether they have a bike like (and how it’s placed), and if the routes are even bike routes or just routes that riders comfortable jostling in traffic like me took. Comfortable riders may also skew the data by being willing to “lane split” at red lights to pass stopped cars rather than waiting at the back in lane.
Having biked a lot in SF, my impression is the best protected bike lanes are on wide roads like Folsom/Howard, Fell/Oak, etc. where proximity isn’t generally an issue, but I’d expect intersections to be riskier due to higher car speeds. While cars passing on isn’t an issue on the Wiggle with a critical mass of riders, on neighborhood streets where sharing the road is obligated the drivers can be scariest, especially in the Sunset. In NYC, an abundance of one lane, one way streets make controlling an entire street easier.
The reality of city design at the moment is almost any bike route will require the sharing the road with cars at some point, usually at the start and end of a ride, because bike lane and “bike route” coverage is often poor in residential areas and business districts.
There are a number of commercial solutions in this space. It's weird when there's a press release like this that acts like their solution is completely novel and unrelated to anything else.
Roadio has front and rear facing cameras with AI driven object detection to help keep cyclists and motor scooter riders safer.
Roadio is primarily a camera and costs around $265 USD. The Garmin is also a camera and also costs over $300 USD. Neither reports to a central service to map the results for other users.
This device would also be useful in places with street-side bike lanes or no bike lanes at all, to see how closely bicyclists ride next to parked cars.
Dooring remains one of the greatest threats to bicyclist safety in many locations. Even places with great bike infrastructure often have streets with parking where cyclists must ride.
https://www.openbikesensor.org/
is pretty popular at least here in Germany.
It's a bit bigger and works with ultrasonic distance measurement. Apart from that (and some other features) it's basically the same idea...
As a long-time cyclist and former bike courier, I think most of the proximity concerns are probably of my own doing. I wonder if the device somehow accounts for this.
My initial reaction is that an accelerometer might be a better data-point, or combining this with accelerometer data.
I'm working on the assumption that a smoother path means I am interacting less with traffic or other hazards.
Given a choice between a street where the cars are stuck in 2km/hr traffic and I'm passing them with a less than foot (0.3m) gap, or a street with 70km/hr traffic where they're passing me with a 1 meter (3 foot) gap... the former feels a lot safer.
Admittedly these streets aren't usually close together (either in time or space), but I've certainly biked on both.
I wonder if this can be predicted by a heat map of car crashes in your area. This is based on my private hunch that car crashes are a predictor of bike crashes. After all, if a car can crash into another car, or a stationary object such as a tree or a building, then it can crash into another bike. And the causes may be similar: Speed and inattention.
On such a map for my locale, the most crash-prone roads are exactly the ones that I instinctively avoid.
One potential issue with counting is that crashes aren't created equal. To reference back to the extremes I discussed above, if I crash when I'm going 5km/h and it's going 2km/h... it's fine*. If I crash going 30km/h with a car going 70km/h I likely have life altering injuries (or am dead, though I believe the statistics say I'm actually pretty likely to survive a collision at that speed differential).
I.e. fender benders between cars (and between cars and bikes, I assume) are common, but not really what we care about.
Not to say it wouldn't be an interesting map to make.
* I've never been involved in a collision, but I assume I'd be fine at these speeds and any damage minimal.
Indeed, that's a good point. My state maintains a map of reported crashes, and most of the dots on the map in my locale are on the highest speed roads. It seems like when the cars are going slower -- and there are fewer of them -- there are fewer crashes. And if the severity is less, like you say, then that's a compounding factor.
We're not NYC, where every street is packed with moving and parked cars. Most of the traffic is on the faster roads, and the cyclists tend to thread our way through the sleepy residential streets. That's good enough separation for me. The parts of town where bikes have to mix with cars, are where they focus more attention on bike lanes.
> It seems like when the cars are going slower -- and there are fewer of them -- there are fewer crashes
Yes, because the throughput of that fast, high density road is so much bigger. Subjectively it feels like it has something like 2x the amount of cars, and when we look at accident density we may very well correct by that factor, but in reality the difference in throughput is much bigger. Number of cars present at a given point in time x speed. That quiet road, it's close to having no car throughput at all compared to the big one, but it still sees the occasional accident.
In my area there has been a program for years where you can sign up to mount a device like this to your bike for pretty much this exact same purpose. From memory it goes behind your seatpost thougho which seems less annoying.
Safe cycling routes are misunderstood. The best thing is taking the lane so you are actually visible. If you take the lane, most streets become very safe and mundane in my experience. Four lane roads are even better than two lane because people can easily merge around you, you can stay out of dooring range and be very visible to traffic. On two lane roads people tend to get a little angry if you take the lane, although that is what you absolutely must do because the alternative is riding in the door zone and people squeezing you passing in the same lane.
In an area where motorists are used to bikes being on the roads this is an effective approach. I nearly got killed in Portland trying this. Apparently they aren't used to share the road with bike. Which was surprising to me given the city's reputation. I'm much more comfortable doing this in the Bay Area where there a hundreds of bikers on the roads at pretty much all times.
Taking the lane (vehicular cycling) often works well in slow-moving traffic, but it breaks down in when there is a large speed differential between the cyclist and car traffic. Effectively, you are in the way and drivers won't expect you to be there.
For these faster roads it is necessary to have dedicated cycling infrastructure, including Dutch-style safe intersections. Otherwise only risk-tolerant or desperate people will cycle.
As a cycling commuter I'm happy with margin. Give me roads and bike lanes that are wide enough to allow me to navigate with margin of safety. The problem with separate bike tracks is that they are rarely built because of the cost and politics involved. Bike trails are a nightmare because inevitably you need to share them with pedestrians. We just need spaces where cars and bikes can coexist. I think that cities in the Bay Area do a good job with this. Turning a 4 lane road into a two lane road with bike lanes, or eliminating parking on the side of the road are much easier to do, and very effective. Don't let the perfect be the enemy of the good enough.
> The cost of bike lanes isn't too bad. Unlike a car road it doesn't require a lot of maintenance.
Tell that to cyclists used to navigating mandatory bike infrastructure full of terribly broken up surface. If car lanes were that quality, people would put the authorities under permanent siege with torches and pitchforks, for refusing to maintain roads.
"Oh, but that road is fine, few spots where you have to step out of the car to push it". For some reason, people responsible for bike infrastructure (outside .nl or Copenhagen) tend to think that it's ok to slow down to walking speed or dismount, on main routes. Imagine similar things required from drivers.
> The wear and tear on tarmac is directly related to the weight of the vehicles that use it.
From empirical studies, damage to the road is proportional to the fourth power of axle weight. A bike with rider may weigh 200 pounds, where a passenger car weighs around 4000 pounds. That 20x difference in weight results in a 80,000x difference in damage to the road.
(That’s not even getting into semi trucks, which are around 40 tons fully loaded. Split along 5 axles rather than 2, that’s 9x the axle load of a passenger car, leading to 6,500x the damage to the road relative to a passenger car, or 520 million times that of a bike.)
Even though mapping out safe routes can help, it's by far more a cultural and political problem that does not have technological solutions. You need separate bike lanes or completely separate bike paths, you need separate traffic lights for bikes. You need to change laws so that car drivers are always legally responsible for damage, even if a cyclist/pedestrian caused the accident (because it makes car drivers more careful/aware). You need to train car drivers to be more aware of cyclists, starting with simple things like knowing how to open a door carefully. You need a police force that conducts a deep investigation when a cyclist gets hit and a municipality that changes the layout of the roads to decrease the probability of it happening again. Etc.
I live in a country that is cycling walhalla, where there are more bikes than citizens, where a good chunk of the population go to work and do groceries by bike and we do all of the above.
There's a way to walhalla. Infrastructure, training, and liability laws prime the pump. When almost everyone is a cyclist, every driver knows that any cyclist could be a friend or family member. Or themselves.
Also... The Dutch reach. Open the driver's side door with the other hand to make sure you look for cyclists. In 12 years in Amsterdam I have never won the 'door prize'.
Honestly, the problem is, in most of the cities, people who drive almost never bike. If everyone biked, while driving, you would somewhat understand how the person on the bike reacts to their surroundings.
Tokyo is pretty sweet to bike around right now, despite the lack of dedicated bike lanes. It’s not as great as my times in Netherlands / Denmark, but it’s great nevertheless. It’s a bit weird, because almost everyone switches between roads and sidewalks, but you get used to it. For that, you need to make biking the superior mode of transportation for certain trips. With e-bikes, that is the case for a lot of activities within Tokyo.
Honestly, the problem is, in most of the cities, people who drive almost never bike.
That's true, but you have to bootstrap it. People will also not bike if it's not safe or attractive to do. In the city I live in, the city center was pretty unsafe for pedestrians and cyclists until the end of the 70s. Two persistent politicians decided to pretty much ban cars from the city center [1], which led to a lot of protests. They persisted and in 1977 the switch was flipped on a single day. Nowadays everyone here is in favor of this and other cities have made the same change, because people realize now that a city center without cars is much nicer: you can walk around much more carelessly, the air is cleaner, etc. Also, it made biking far more attractive, because you can get from the outskirts of the city to some shop much faster by bike than by car.
Since then, the cycling network has been continuously optimized to be able to travel between different points in the city as possible as quickly as possible and with as few interactions with cars as possible. And there are other amenities like traffic light that increase priority for cyclists when it is raining (to encourage people to cycle even when it is raining).
The same is true outside the cities, where there is a dense cycling network, largely separated from car roads. Both for fast work <-> home routing and for recreational cycling. The latter is the so-called fietsknooppunten network that prefers nice routes through nature, etc. over short routes [2].
[1] Article in Dutch: https://www.aanpakringzuid.nl/actueel/nieuws/verhalen/straks... , Google translation: https://www-aanpakringzuid-nl.translate.goog/actueel/nieuws/...
[2] Fietsknooppunten: https://www.fietsknoop.nl/planner
Here's an underappreciated problem with biking in cities: storage. Most people in cities live above ground[0], and buildings don't have dedicated bike storage. Bike theft is common, and is a unique crime in being simultaneously highly disrupting to the victim, trivial to pull off, and not big enough monetarily for the police to bother pursuing - so you can't really park on the street overnight like you'd do with a car; it's too risky. This means people end up storing bikes in their apartments. Bikes are heavy and unwieldy and full of pointy bits and hard edges; going up and down with them is super annoying, especially if you don't have a lift (or it isn't big enough to fit a bike).
Solve the storage problem, and a lot more people city dwellers owning a bike will start using it daily, and many of those who don't will buy one.
--
[0] - Follows obviously from assuming most buildings have at least one floor.
All of this is just cultural cope. Bikes are stolen in Tokyo and Amsterdam as well. Tokyo space is incredibly limited. And etc.
The problem is, biking is just not efficient compared to other transport modes in super majority of the cities in NA. There is no political appetite either. People just love their cars, and can’t be bothered to restructure their lives like my friends in Paris did.
Foldable (brompton for example) bikes, and owning a shitty bike are common solutions to this problem.
Shitty bikes are just as heavy, if not more, than good bikes.
Automatic blaming of a driver is a horrific idea. Immediately unintended consequences spring to mind, cyclists purposely cycling into cars to get an insurance claim for one. This might sound far fetched but my friends in the UK police deal with pedestrians who throw themselves in front of slow moving vehicles in an attempt to get a damage claims.
I cycle to work, and I came here to ask if there's a crowd sourced city map that shows cyclist traffic accident black spots as part of my cycle route is genuinely frightening due to traffic.
This is the correct answer. One big problem is that your "safe bicycle path" can be made unsafe by a motorist that forgot to check for bicycles at any second. That can be parked cars, cars that turn right or or motorists that narrowly overtake with a high speed or whatever.
And the best solution for this is to create a separate space for bicycles that can't be accidentally violated without running into some sort of barrier. The next best thing is probably to include certain things in the the education for the drivers license that give people the empathy and perspective of what it feels like if you are on a bicycle and some asshole overtakes you with 70 km/h and half an arm of distance.
The Dutch cycling embassy website provides some basic principles on this: https://dutchcycling.nl/expertises/cycling-behaviour/ and on infrastructure https://dutchcycling.nl/expertises/cycling-infrastructure/
In my opinion the biggest problem is people who design roads/infrastructure don't bike. When they bike they will know what to do and how to pay attention.
So right now there is this huge push in EU to make more bike infrastructure. But people making it ... don't bike. At least not everywhere. And where they don't they will inevitably make bad bike infrastructure. This could just be corners that are too tight. Bad incline on a corner for example will not be obvious to someone who never bikes, could be just a few degrees. But on a bike it's deadly! Maybe not on dry asphalt, but bring some rain, sand, whatever and people will fall.
And then we can start talking about culture.
> Maybe not on dry asphalt, but bring some rain, sand, whatever and people will fall.
Oh man, here in Paris there's been a huge push for people to take up biking since Covid. But many bike paths are unbelievably stupid. Sure, many are too narrow, switch sides all the time, etc. I understand they had to do those in a hurry, it costs money to make them wider, etc.
But the most baffling thing is that some are actually painted with some slippery paint for some reason. I'm not talking about signs or delimiting lines, I'm talking about the underlying asphalt being fully painted, so that you're riding on the paint.
Bonus points for some of these particular paths going through a pretty pedestrian-dense area, and on the sidewalk, between parked cars on the left and pedestrians on the right who have to cross the bike path in order to reach the waiting area to cross the road. So you're very likely to have to emergency brake. I usually ride using the local bike sharing scheme, and even though those bikes are in questionable state, you're guaranteed to have the wheels skid when braking somewhat hard.
I was curious if the sensor would pick up other things like trees or other cyclist, but it seems like they accounted for that:
> We then log a sensor events [sic] if the majority of cells in the sensor frame agree to the same value within a threshold parameter [...]. This ensures that sensor events are only logged when large objects like cars block the sensor’s field-of-view , i.e., one or more small objects like branches or distance pedestrians in the sensor’s field-of-view will not trigger this condition. While there is no guarantee that this approach strictly identifies cars, we empirically saw during testing that passing cyclists and pedestrians rarely satisfied this condition at the typical passing distance due to the wide field-of-view of the VL53L8.
Also interesting that it's quite cheap to build:
> The whole system can cost less than $25 [...]
From the paper https://dl.acm.org/doi/10.1145/3706598.3713325
So if I’m in a protected bike lane with a row of parked cars to my left wouldn’t it be flagging every parked car as a potential hazard?
Unless there's enough distance to the bike lane every parked car in a row of parked cars is a potential hazard. It's even got it's own name: dooring.
I assumed it could tell whether the car was passing you or vice versa.
From the photos, there appears to be more than one sensor on the device which may be used to tell which direction the large object is coming from. Unless you were cycling backwards or mounted the device the wrong way around you shouldn't have any stationary cars passing you. Just a guess though.
I don’t know Seattle so I’d be curious to know if the proximity and accident hotspots are also high traffic zones in general, whether they have a bike like (and how it’s placed), and if the routes are even bike routes or just routes that riders comfortable jostling in traffic like me took. Comfortable riders may also skew the data by being willing to “lane split” at red lights to pass stopped cars rather than waiting at the back in lane.
Having biked a lot in SF, my impression is the best protected bike lanes are on wide roads like Folsom/Howard, Fell/Oak, etc. where proximity isn’t generally an issue, but I’d expect intersections to be riskier due to higher car speeds. While cars passing on isn’t an issue on the Wiggle with a critical mass of riders, on neighborhood streets where sharing the road is obligated the drivers can be scariest, especially in the Sunset. In NYC, an abundance of one lane, one way streets make controlling an entire street easier.
The reality of city design at the moment is almost any bike route will require the sharing the road with cars at some point, usually at the start and end of a ride, because bike lane and “bike route” coverage is often poor in residential areas and business districts.
I am willing to give it a good try even if it's never perfect!
I live in a major city and the increased traffic from scooters almost feels like it could support a separate lane even if bikes didn't exist
There are a number of commercial solutions in this space. It's weird when there's a press release like this that acts like their solution is completely novel and unrelated to anything else.
Roadio has front and rear facing cameras with AI driven object detection to help keep cyclists and motor scooter riders safer.
https://www.roadio.com
Garmin (amongst others) has had a rear mounted radar (and bike light) system for a while. They also have one with a camera built in.
https://www.garmin.com/en-US/p/698001/
https://www.garmin.com/en-US/p/721258/
Roadio is primarily a camera and costs around $265 USD. The Garmin is also a camera and also costs over $300 USD. Neither reports to a central service to map the results for other users.
Strava has heat maps.
Read beyond the title ... none of those have anything to do with this.
Next step is to connect the sensor to a can of pressured brake fluid that sprays onto the paintwork of vehicles passing too close.
I know you’re joking but there’s a simpler way to get the same effect.
There are people who attach a pool noodle to the back of their bike sticking out straight into the road less than proper passing distance.
They are highly visible and the idea is that drivers avoid them because they don’t know if they will damage their car or not.
In the case of a case of a close pass the pool noodle just bends out of the way.
The was also a laser product that projected a line onto the ground around the cyclist. I don’t think it worked very well though.
This device would also be useful in places with street-side bike lanes or no bike lanes at all, to see how closely bicyclists ride next to parked cars.
Dooring remains one of the greatest threats to bicyclist safety in many locations. Even places with great bike infrastructure often have streets with parking where cyclists must ride.
https://www.openbikesensor.org/ is pretty popular at least here in Germany. It's a bit bigger and works with ultrasonic distance measurement. Apart from that (and some other features) it's basically the same idea...
As a long-time cyclist and former bike courier, I think most of the proximity concerns are probably of my own doing. I wonder if the device somehow accounts for this.
My initial reaction is that an accelerometer might be a better data-point, or combining this with accelerometer data.
I'm working on the assumption that a smoother path means I am interacting less with traffic or other hazards.
I’m not sure how much that matters. You won’t need to initiate close passes as often on a safer street.
Given a choice between a street where the cars are stuck in 2km/hr traffic and I'm passing them with a less than foot (0.3m) gap, or a street with 70km/hr traffic where they're passing me with a 1 meter (3 foot) gap... the former feels a lot safer.
Admittedly these streets aren't usually close together (either in time or space), but I've certainly biked on both.
Still, imperfect data can be better than no data.
I wonder if this can be predicted by a heat map of car crashes in your area. This is based on my private hunch that car crashes are a predictor of bike crashes. After all, if a car can crash into another car, or a stationary object such as a tree or a building, then it can crash into another bike. And the causes may be similar: Speed and inattention.
On such a map for my locale, the most crash-prone roads are exactly the ones that I instinctively avoid.
One potential issue with counting is that crashes aren't created equal. To reference back to the extremes I discussed above, if I crash when I'm going 5km/h and it's going 2km/h... it's fine*. If I crash going 30km/h with a car going 70km/h I likely have life altering injuries (or am dead, though I believe the statistics say I'm actually pretty likely to survive a collision at that speed differential).
I.e. fender benders between cars (and between cars and bikes, I assume) are common, but not really what we care about.
Not to say it wouldn't be an interesting map to make.
* I've never been involved in a collision, but I assume I'd be fine at these speeds and any damage minimal.
Indeed, that's a good point. My state maintains a map of reported crashes, and most of the dots on the map in my locale are on the highest speed roads. It seems like when the cars are going slower -- and there are fewer of them -- there are fewer crashes. And if the severity is less, like you say, then that's a compounding factor.
We're not NYC, where every street is packed with moving and parked cars. Most of the traffic is on the faster roads, and the cyclists tend to thread our way through the sleepy residential streets. That's good enough separation for me. The parts of town where bikes have to mix with cars, are where they focus more attention on bike lanes.
> It seems like when the cars are going slower -- and there are fewer of them -- there are fewer crashes
Yes, because the throughput of that fast, high density road is so much bigger. Subjectively it feels like it has something like 2x the amount of cars, and when we look at accident density we may very well correct by that factor, but in reality the difference in throughput is much bigger. Number of cars present at a given point in time x speed. That quiet road, it's close to having no car throughput at all compared to the big one, but it still sees the occasional accident.
Just to plug a friend… Velo.ai does similar things… but has other stuff going on: https://www.velo.ai/
Interesting to see how these two would compare, but my first (light) glance points to velo.ai being further along…
In my area there has been a program for years where you can sign up to mount a device like this to your bike for pretty much this exact same purpose. From memory it goes behind your seatpost thougho which seems less annoying.
Sounds like https://www.openbikesensor.org/
But I haven't heard of any "official" programs.
Safe cycling routes are misunderstood. The best thing is taking the lane so you are actually visible. If you take the lane, most streets become very safe and mundane in my experience. Four lane roads are even better than two lane because people can easily merge around you, you can stay out of dooring range and be very visible to traffic. On two lane roads people tend to get a little angry if you take the lane, although that is what you absolutely must do because the alternative is riding in the door zone and people squeezing you passing in the same lane.
In an area where motorists are used to bikes being on the roads this is an effective approach. I nearly got killed in Portland trying this. Apparently they aren't used to share the road with bike. Which was surprising to me given the city's reputation. I'm much more comfortable doing this in the Bay Area where there a hundreds of bikers on the roads at pretty much all times.
Taking the lane (vehicular cycling) often works well in slow-moving traffic, but it breaks down in when there is a large speed differential between the cyclist and car traffic. Effectively, you are in the way and drivers won't expect you to be there.
For these faster roads it is necessary to have dedicated cycling infrastructure, including Dutch-style safe intersections. Otherwise only risk-tolerant or desperate people will cycle.
A solution in search of a problem.
Safe bicycle routes need to be created by building inherently safe infrastructure: protected intersections and separate bicycle tracks.
As a cycling commuter I'm happy with margin. Give me roads and bike lanes that are wide enough to allow me to navigate with margin of safety. The problem with separate bike tracks is that they are rarely built because of the cost and politics involved. Bike trails are a nightmare because inevitably you need to share them with pedestrians. We just need spaces where cars and bikes can coexist. I think that cities in the Bay Area do a good job with this. Turning a 4 lane road into a two lane road with bike lanes, or eliminating parking on the side of the road are much easier to do, and very effective. Don't let the perfect be the enemy of the good enough.
> The problem with separate bike tracks is that they are rarely built because of the cost and politics involved.
The cost of bike lanes isn't too bad. Unlike a car road it doesn't require a lot of maintenance.
> Bike trails are a nightmare because inevitably you need to share them with pedestrians.
This is a political issue, here you have plenty of bike trails just for bikes.
> The cost of bike lanes isn't too bad. Unlike a car road it doesn't require a lot of maintenance.
Tell that to cyclists used to navigating mandatory bike infrastructure full of terribly broken up surface. If car lanes were that quality, people would put the authorities under permanent siege with torches and pitchforks, for refusing to maintain roads.
"Oh, but that road is fine, few spots where you have to step out of the car to push it". For some reason, people responsible for bike infrastructure (outside .nl or Copenhagen) tend to think that it's ok to slow down to walking speed or dismount, on main routes. Imagine similar things required from drivers.
I did say it was low maintenance, not that it was maintenance free.
> Tell that to cyclists used to navigating mandatory bike infrastructure full of terribly broken up surface.
We’ve had paved, off-road bike lanes where I live since the 80s.
They’re not mandatory but they are highly used and to my knowledge have required almost no maintenance in all that time.
There’s no scaring or resurfacing visible.
The wear and tear on tarmac is directly related to the weight of the vehicles that use it.
The benefits of bike lanes are massive compared to the cost.
> The wear and tear on tarmac is directly related to the weight of the vehicles that use it.
From empirical studies, damage to the road is proportional to the fourth power of axle weight. A bike with rider may weigh 200 pounds, where a passenger car weighs around 4000 pounds. That 20x difference in weight results in a 80,000x difference in damage to the road.
(That’s not even getting into semi trucks, which are around 40 tons fully loaded. Split along 5 axles rather than 2, that’s 9x the axle load of a passenger car, leading to 6,500x the damage to the road relative to a passenger car, or 520 million times that of a bike.)
[0] https://en.wikipedia.org/wiki/Fourth_power_law
I agree. Finding a safe route that exists has never been remotely challenging.
Needs Strava integration