road projects and congestion.
(Photo © J. Maus)
Bikes do a lot of great things for our city. We often hear about the environmental benefits, the health benefits, and so on. But what about the reduced impact on our road network and congestion? What if more Portlanders drove cars into the city instead of bikes?
According to PBOT bike coordinator Roger Geller, we would have had to spend millions on wider roads and we’d be stuck in traffic a lot more often.
During a presentation given to congressional staffers on Capitol Hill at the National Bike Summit back in March, Geller made the case that it’s much nicer to drive into downtown Portland and our city has saved a ton of cash, simply because the increase in vehicle traffic on the Hawthorne Bridge is bicycles and not private automobiles.
Below are two slides from Geller’s presentation that tell this story. Each one is followed by his slide notes (emphasis mine):
The total number of vehicles on the Hawthorne Bridge has increased 20% since 1991…This increased demand for mobility is consistent with what most traffic models would predict, given increases in population and increased economic activity. This type of increased demand for mobility can spell problems for road users: more congestion, more delay and less travel reliability.
But….
In the case of the Hawthorne Bridge, the negative effects of congestion have been kept at bay. Because, while the number of vehicles increased 20% between 1991 and
19982008, that increase has been almost wholly in bicycle traffic. Had the increase been—as it might be in most places—automobiles, then the intersections at either ends of the bridge would likely have failed in their ability to effectively and efficiently move traffic.The engineering solution to this type of congestion would have been to widen the intersections, add more travel lanes to the bridge, add more green time to the movements onto the bridge. In reality, because there are scant funds for such improvements, nothing would have been done and the costs would have been those of increased congestion.
However, because the increased demand for mobility has been borne almost exclusively by the bicycle, automotive traffic flows in this area the same today as it did in 1991. It is for this reason, in part, that Portland’s award winning traffic engineer, Rob Burchfield, states that: “Bicycling infrastructure is relatively easy to implement and low cost compared to other modes. It is by far the most cost-effective way to provide for personal mobility in an urban transportation system.”
Add this to your quiver of weapons to battle non-believers.
Thanks for reading.
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Bike users freeing up roads and parking for motor vehicle users is often ignored when allotting funds for bike projects. I know Todd Boulanger, formally of the City of Vancouver, frequently discussed the traffic and maintenance benefits that came with increasing foot and bike traffic.
Something the article did not address is the the volume of persons able to use mass transit instead of driving. A full buss takes a lot of cars off the road and reduces the burden on infrastructure as well.
Bike users freeing up roads and parking for motor vehicle users is often ignored when allotting funds for bike projects. I know Todd Boulanger, formally of the City of Vancouver, frequently discussed the traffic and maintenance benefits that came with increasing foot and bike traffic.
Something the article did not address is the volume of persons able to use mass transit instead of driving. A full buss takes a lot of cars off the road and reduces the burden on infrastructure as well.
I would like to see the same charts for all bridges. The Hawthorne is the most bike friendly compared to the nearby Ross Island and Morrison bridges. Therefore its use figures might be skewed because cyclist favor it.
Did automobile use of the neighboring bridges stay flat also?
Did bicycle traffic on those bridges rise?
I think you got an 1998 in there that should have been a 2008
I recall that BikePortland published the results of a PBOT survey a couple years ago showing that about 80% of bike commuters would be driving if they weren’t biking. If that’s so, maybe buikes should get “just” 80% of the credit for keeping automotive vehicle counts flat.
These are very interesting statistics, but one must wonder about the conclusions that have been made. I think we can all agree that bikes have reduced the growth of automobile traffic across the bridge, but that may not be completely attributable to bikes. The idea of triple convergence (or divergence in this case) may suggest that the automotive facilities are at their maximum, so drivers would rather take other routes, other modes, or drive at other times. Similarly, building bike infrastructure to reduce motor vehicle demand and congestion is not an effective strategy; yes, some drivers may choose to ride, but studies show that others will take their place. Of course, building new facilities for bikes allow more users to be served for much lower investment, but can’t realistically reduce auto levels.
I say this merely to caution us from jumping to conclusions about the data, but I don’t want to diminish the significance of these figures. These are remarkable figures (but really need to be contextualized by measurements from the other bridges, as was mentioned), and hopefully they can serve to educate other planners–and out citizens–to the potential of investing in bicycle infrastructure. It benefits everyone, not just cyclists.
@ JE #3
I just looked at the annual ODOT counts for the Ross Island Bridge. The annual traffic volume growth has been averaging about 2% per year since 1993; peaking in 2005. The trend does not show nice linear growth it isn’t flat either.
Thats my bridge of choice when crossing 🙂
“According to PBOT bike coordinator Roger Geller, we would have had to spend millions on wider roads and we’d be stuck in traffic a lot more often.”
I’m confused. how does bicycle traffic across a single, small bridge in downtown Portland support such a weird conclusion about the entire city?
It doesn’t. Anybody with a critical mind and 30 seconds can see why. And it’s this kind of amateurish, Powerpoint-happy statistical make-believe that make folks wanting a focus on more critical priorities upset.
Listen, fellow bicyclists: you’ve really got to take a deep breath amd take a big, slow step back from this kind of stuff. Look around. And if you do nothing else, pause to consider what other groups use terms like “non-believer” and “battle”.
“The engineering solution to this type of congestion would have been to widen the intersections, add more travel lanes to the bridge, add more green time to the movements onto the bridge.”
No, not really. traffic engineering could muster all sorts of other options, and usually does–like it has for the Hawthorne bridge over the past century. In fact, “widening” a bridge is not something that’s normally done. It would be a truly bizarre design decision.
And you’re ignoring the most easily accessible and obvious reason for a flat curve for that bridge’s traffic–*the number of people making trips into and out of downtown has declined, because businesses and retail there has declined* since 1991. Those people that would have traveled the Hawthorne bridge?
They’re headed farther and farther out, where the jobs are. The tiny fraction of people who actually ride a bicycle into the downtown core to work represent…a tiny fraction. Downtown PDX has never been the jobs and business hub of Portland.
You all knew that, right?
This is exactly the sort of data the city should see more of amid the bike plan debate. Though I think @another bicyclist has a solid point: the Hawthorne Bridge numbers definitely can’t be extrapolated across the city. But they’re not for nothing.
And you’re right about the efficiency of buses, @Marcus Griffith, but the sad fact is that transit use is up only slightly since 1991:
http://www.humantransit.org/2010/01/portland-another-challenging-chart.html
Wouldn’t it be great if posting was not anonymous? blueoregon got rid of it. People may then be a bit more substantive in their posts.
The traffic volumes on the four bridges that have been bicycle-friendly for the past decade or so (Broadway, Steel, Burnside & Hawthorne) have seen essentially no growth in automobile trips. Bicycle use on these bridges has grown about 13% since 1991. That means that the overall number of vehicle trips across these bridges has grown 13% over this time period. So, at least on these bridges, the number of people making trips into and out of downtown has not declined–it has grown–and much of that growth has been by bicycle. You can see the numbers on the last page of the 2009 City Bicycle Count.
As for spending millions of dollars; if all the increased trips on the Hawthorne Bridge had been by automobile rather than bicycle, traffic operations on and approaching the bridge would have likely failed. One standard traffic engineering recourse to that is to add more travel lanes and add more green time for traffic flowing onto the bridge and at the same time add more turn lanes at the intersections feeding the bridge in order to separate out the traffic turning before the brdige from that heading onto the bridge in order to be more efficient. Were the bridge not a bridge but just a standard roadway, treatments like that could easily have cost several million dollars–not all around town–just for that bridge. That type of traffic engineering goes on in jurisdictions all across the country all the time. Even in the Portland region. Many years ago Portland widened West Burndside Street in part, by slicing up the buildings on the south side of the street and moving back their facades far enough to create more travel lanes. In today’s dollars that would have cost a pretty penny.
This example of the Hawthorne Bridge is just that: an example. It is an example of how bicycle transportation can be delivered for pennies on the dollar compared to delivering the same level of service for automobiles and how increased bicycle use benefits not just people riding bicycles, but truly everybody using the transportation system.
Thanks for sharing this, Jonathan!
Looking for more arrows for your quiver? Check out some of this propaganda! http://intersection911.org/investinbikes.pdf
Good stat analysis is never this clear!
Sorry, but the conclusions drawn here ignore a lot of factors, such as those brought up by another bicyclist.
I love bicycles, and I ride a bicycle everywhere I can… but the conclusion drawn here (that traffic increases can be absorbed by good bicycle facilities) seems to be way too simplistic to be taken seriously (hopefully) by anyone involved in making serious infrastructure planning decisions.
Mine isn’t an argument against bike infrastructure, but an argument against lazy stat analysis in the name of converting heretics to bicycle green jesusification… bad stats actually make baby green jesus cry.
“Were the bridge not a bridge but just a standard roadway, treatments like that could easily have cost several million dollars–not all around town–just for that bridge. That type of traffic engineering goes on in jurisdictions all across the country all the time.”
Sure it does. Now, can you explain how a bicycle increase on the Hawthorne Bridge equals a net auto traffic *decrease* in the Portland area? Because, in fact, auto traffic in PDX *has not* decreased.
So: if more bicycles go across a downtown bridge, but auto use continues to grow in PDX, what does *that* “example” tell us?
“This example of the Hawthorne Bridge is just that: an example. It is an example of how bicycle transportation can be delivered for pennies on the dollar compared to delivering the same level of service for automobiles”
Except that it isn’t. What it is, really, is a statistic, purposely removed from a larger context.
another bicyclist et al:
What has happened on the Hawthorne Bridge, and on other bicycle friendly bridges in downtown, reflects the increased demand for mobility that comes with the increased economic activity and population growth that has occurred in Portland. You put those two together and you have more people taking more trips. Those 16,000 plus trips taken across the bridge in 2008 reflect that increased demand for mobility. This is not to say that all new trips were by bicycle. Some people switched from driving, some new people biked and never drove, and some new people drove and never biked.
However, given that the overall number of trips is going to increase, the question then becomes: how do we wish to serve the increased demand for mobility? Those 16,000 trips were going to occur regardless of vehicle type. That they were taken by bicycle means that the bridge is able to function as well for automoibles today as it did in 1991. More importantly, we were able to serve those trips for a small fraction of what it would have taken to serve them had they all been automobile trips.
The key, of course, is to grow bicycle trips and mode split. When we’ve achieved 25% or more bicycle mode split then you see many fewer automobile trips. Look at the chart of Copenhagen’s experience with bicycle trips and automobile traffic into their inner city. It’s on page 7 in the 2009 Count Report. Bicycle trips climb more rapidly than automobile trips decline, but they do decline.
I always thought that the best public service message for bicycling ought to be how it reduces other forms of traffic at peak hours – one less cage on the road.
This is quite noticeable when I have to drive to work and back – If I take local roads instead of 99E (or for sake of comparison, the interstates), there is less congestion.
Only when you get on the interstate that the traffic morass starts, these are the people who by choice live more than 10 miles out and have to drive to work.
Re: another bicyclist:
“No, not really. traffic engineering could muster all sorts of other options, and usually does–like it has for the Hawthorne bridge over the past century. In fact, “widening” a bridge is not something that’s normally done. It would be a truly bizarre design decision.”
another bicyclist, do you realize the irony of your statement? The Hawthorne was widened in 1999!
Put the $ in BIKE$ 🙂
Roger, how do you reconcile this:
“What has happened on the Hawthorne Bridge, and on other bicycle friendly bridges in downtown, reflects the increased demand for mobility that comes with the increased economic activity and population growth that has occurred in Portland.”
With this:
“You’re ignoring the most easily accessible and obvious reason for a flat curve for that bridge’s traffic–*the number of people making trips into and out of downtown has declined, because businesses and retail there has declined* since 1991.”
???
AaronF:
Total vehicle trips on four bridges in 1991: 116,059. Total vehicle trips on four bridges 2008: 129,731. “Total vehicle trips” refers to bicycles, private automobiles and buses.
“another bicyclist, do you realize the irony of your statement? The Hawthorne was widened in 1999!”
No, the pedestrian paths were slightly widened. The main reason for that was *pedestrian* complaints, not “number of bicycles”; pedestrians were getting pushed down the food chain, forced towards auto traffic, getting hit, etc.
“Total vehicle trips on four bridges in 1991: 116,059. Total vehicle trips on four bridges 2008: 129,731. “Total vehicle trips” refers to bicycles, private automobiles and buses.”
And “total trips” does not equal “total people”. And of course, your post didn’t reconcile the posts like Aaron asked.
It’s worth pointing out that the numbers are even more generous to non-automobile modes when considering person-trips rather than vehicle trips, because then the benefits of transit are more accurately reflected. Average automobile occupancy in this country has dropped consistently since the 1960s, to the point where each automobile trip for all intents and purposes essentially represents just one person trip. In contrast, because average occupancy for buses and trains – particularly those across Portland’s bridges – is so much higher, a single bus or train represents many many person trips.
re: Jerry K #6: I think you’d be surprised how effectively the multi-modal nature of the Hawthorne Bridge DOES in fact reduce automobile demand and related congestion. The share of peak automobile person-trips on the Hawthorne (taking into account average occupancy) is roughly 55%, and auto trips overall have remained relatively constant since the early 1990s. However, because total person trips have steadily increased, the share of auto trips has consistently declined. If there truly were gobs of latent automobile demand, you’d expect to see growth in automobile trips rather than a relatively flat slope. And it’s not because the Hawthorne is particularly congested. Stand out there during peak periods and you’ll actually find that it operates – practically – at fairly high level of service for automobiles. Triple convergence would suggest that many of the folks who have chosen to bike, walk, and take transit since the 1990s would see all this latent auto capacity on the bridge and take advantage of it by switching to driving to save time, but that hasn’t happened!
another bicyclist:
The bridge pathway was widened as part of the overall maintenance on the Hawthorne Bridge in large part because the city of Portland pushed to have it widened and contributed funding to the project to make it happen. Pedestrians were not getting hit, forced towards auto traffic, etc…It was a project to provide better conditions for cyclists and pedestrians.
Total trips does not equal total people, but the general assumption about occupancy of private automobiles is pretty close to 1.
I’m not sure of the source of the statement that there are fewer trips into Downtown today than there were in 1991. Who says that’s the case? What’s the source of that data?
Regardless, I think you’re missing the point. The point is that our roadways can only accommodate so many motor vehicle trips before congestion approaches levels that most people will find unacceptable. There will always be an enduring need for mobility–for people to go from point A to point B. To the extent that we can encourage more use of bicycles then we preserve roadway capacity and mitigate for the potential effects of congestion, which include: expensive capital projects to restore roadway capacity or increased congestion that delays the movement of people and goods and all the negatives associated with that.
Ultimately it comes down to a question of how would you prefer those 16,700 trips to have been made across the four bridges in 2008? Would you rather they have been on bicycle or would you have preferred they be in private automobiles? Were they in private automobiles–which is where they likely would have been in most other cities–then that additional traffic on the bridges would have resulted in significant congestion.
For example, morning peak hour observations at the intersection of Madison and Grand in 2007 found that approximately 20 motor vehicles go through the intersection (and onto the Hawthorne Bridge) on each green light and about 20 bicycles go through the intersection on each green light. Switching even 10 of those cyclists to automobiles going through the intersection means that the entire queue of cars wouldn’t even come close to clearing the green signal. With each new signal cycle more and more cars would back up until SE Madison Avenue would be backed up during the morning peak for many blocks. This effects not just the motorists but also those using the 3 bus lines on Madison. How would we then address that congestion? A standard engineering response would be: more lanes and/or more green time. Portland has essentially addressed this situation by providing a network of bikeways, wider pathways on the bridge and programs to encourage increased bicycling.
Not only has it worked, but it is a solution we can afford. To the extent that we can encourage more bicycling we can continue to serve well all users of the streets. This is why our City Traffic Engineer states that bicycling is the most cost effective way to provide for personal mobility.
Roger (#17): “Those 16,000 trips were going to occur regardless of vehicle type.”
This makes you sound a bit like those major-label music industry executives who insist that every “illegal download” is a lost sale. Or more to the point, like the freeway/mega-bridge defenders who insist that without more lanes, more capacity, traffic and thus economic activity will snarl and stop. It’s the ol’ induced demand syndrome.
I have made plenty of trips over numerous Portland bridges by bike that I never would have made without a bike. That’s not a bad thing at all — in fact, I appreciate living somewhere where I can decide on a nice day to head out for a nice bike ride, or run an errand I don’t particularly need to run at that moment simply because it is convenient for me to hop on a bike. I might be more inclined to gang errands together and travel around town less often if mobility wasn’t relatively cheap and easy, and even fun.
But that’s very different from saying all those trips would’ve been made regardless. And it doesn’t, in and of itself, justify increasing city spending on bicycle infrastructure without at least an equivalent reduction in overall transportation spending. I’m all for increasing bike mode share, and reprioritizing existing transport funding to redress the imbalance that is currently accorded private motorized vehicle travel. I’m not for reprioritizing BES money to build bike boulevards (er, excuse me, “neighborhood greenways”) in favor of spending it where it is most needed, irrespective of what the Bike Master Plan calls for. I’m not for many of the other accounting tricks the City Council uses to fund pet projects while vital services, housing, medical and mental health care, and our city’s educational system are neglected.
If bike traffic has saved the city so much time and money, as Jonathan’s headline alledges, then we should be spending less per capita on overall transportation needs now than we were 20 years ago. Are we? If we are, I don’t understand why the city can’t simply fund the Bike Master Plan from transportation dollars, and why the rest of the city government doesn’t seem to reaping the rewards of this tremendous savings. Or why we still have so many potholes and unpaved roads. No doubt an $80 million boondoggle like the tram and untold millions for streetcars don’t help. But c’mon, where is the actual savings?
If car traffic is near flat…then where are all those Vancouverites driving to shop and work in Oregon…it must be the Lloyd District or out at IKEA then…it is not at Jantzen Beach (that place is a ghost town now).
Crossing one big old scary bridge a day is enough for any sane driver. 😉
Roger,
Thank you for your responses, but the problem I have with them is that you are only counting the four bike friendly bridges. By leaving the St. Johns, Fremont, Morrison, Ross Island, Marquam and Sellwood bridges out of the equation, your conclusions are left open to doubt. The questions we are raising here are the same ones the anti-bikers will use. We all agree that cycling is the least expensive way to move people around the city. You are preaching to the choir here. But when we go out to spread the word and defend our cause we want a nice, thick and doubt free gospel we can use to (metaphorically) smack the non-believers upside the head with. Using bridge traffic counts is risky to begin with because it leaves out those commuting to downtown from the western suburbs.
What I would like to see are total traffic counts for the city and cost comparisons for each mode; especially maintenance costs. We all know the figures will show cycling saves the city money. That is a very important point in this time of budgets cuts, but we need all the facts, a total package of statistics to make and defend that point.
Well – sure – you could ask all kinds of questions. But the point that Roger is making is really good start:
1) The city spent a little money to make a couple of bikes bridges more bike friendly
2) More bikes (and thus people) crossed those bridges and about the same number of cars over the next N years
3) If Portland had pursued the standard US approach for getting those people across those bridges it would have cost a lot more or resulted in really nasty congestion
Note that none of this argument requires you figure out what’s going on over other bridges or into downtown or whatever else – the (very valid) point is that these people used the inexpensive facility that was provided.
Even so – that’s a pretty big deal. There aren’t too many modes that are cheaper than cycling. So any other mode that they could have taken would have cost more money.
The questions of induced demand is a good one – but think about it – induced bicycle trips are probably net positive (+ on health benefits, very small infrastructure wear) and they are certainly not *all* induced 🙂
Everyone who bothers to think about it figures out that cycling infrastructure is a bargain. So what you need is some good pointed stories for everyone else. (Somehow I don’t think the cycling hater are going to be worrying about induced demand 🙂
I would like to point out that a CRC plan with a decent bike/pedestrian and public transit (AKA light rail) infrastructure would be beneficial to traffic and congestion. As is, it is only condusive to driving and congested traffic.
“I’m confused. how does bicycle traffic across a single, small bridge in downtown Portland support such a weird conclusion about the entire city?”
This is like arguing that a study of vehicle traffic in Portland is not valid if it does not sample the greater metro area, suburbs, exurbs, rural feeder communities, and/or holiday trips.
“Thank you for your responses, but the problem I have with them is that you are only counting the four bike friendly bridges.”
The idea that commuters who cross the Hawthorne bridge would use distant non-bike friendly bridges is silly. The majority of commuters use bridges closest to their homes.
“I might be more inclined to gang errands together and travel around town less often if mobility wasn’t relatively cheap and easy, and even fun.”
As many a slurpee ™ sucking driver can attest to, driving is far more “convenient” than cycling. I personally drove across the bridge far more often than I now bike across the bridge. I have zero desire to bike back to work in the evening.
I generally liked this article and Roger Geller points. While I think there is a bit of fuzzy math here in that one cannot say with certainty that if some of those 20 bikes in the queue at the Hawthorne would automatically go to cars then they would then travel over the Hawthorne rather than say the Morrison etc once they started driving, still the general point and attempt to quantify and qualify the benefits on biking Portland’s transportation infrastructure in general is a worth endeavor. Please just tighten up the analysis and label the assumptions better. At the same time, please continue.
P.S. Geller did not place the certainty on the 20 bicycles example, but I was piggybacking on this example to exemplify the point for the main article.
Spare-wheel claims the idea of cyclists using “distant non-bike-friendly bridges is silly.” That misses the point. Some of us go out of our way to the more-distant Hawthore Bridge. Once Sellwood Bridge is upgraded, I’ll use that instead of Hawthorne for my commute to downtown. Don’t count on me using both. Or I will use TriMet’s new bridge near the Ross Island Bridge. Be careful how you use statistics. I’m really pleased with the progress, but don’t count on short-term trends based on small sample size and tiny initial percentages.
Spare_wheel-
“Thank you for your responses, but the problem I have with them is that you are only counting the four bike friendly bridges.”
“The idea that commuters who cross the Hawthorne bridge would use distant non-bike friendly bridges is silly. The majority of commuters use bridges closest to their homes.”
In my case at least, that is not true. I work in downtown Portland, between the Hawthorne and Morrison Bridges. When I lived in SE, the closest bridge to me was the Ross Island but when I cycled to work I used the Hawthorne. I now live in North Portland. Ignoring the auto only Fremont, the closest bridge would be the Broadway, but I use the Steele. If an event clogs up Waterfront Park and Naito, I’ll use the Esplanade and cross on the Hawthorne.
Cyclists do not always choose the most direct or closest route. Often we choose the easiest.
Read what US Secretary of Transportation Ray LaHood has to say about bicyle infrastructure v. auto infrastructure in his piece titled “What we know about bike infrastructure: people want it.” He expressly compares the relative cost of providing for bicycles v. adding a lane of traffic. The photo he shows on his website is not unlike the Hawthorne Bridge.
“I’m confused. how does bicycle traffic across a single, small bridge in downtown Portland support such a weird conclusion about the entire city?”
following the conversation, you’re doing it wrong…
this is what was quoted:
What if more Portlanders drove cars into the city instead of bikes?
According to PBOT bike coordinator Roger Geller, we would have had to spend millions on wider roads and we’d be stuck in traffic a lot more often.
the bridge wasn’t even brought up yet… they’re just talking about trips, not any particular stretch of road… you got ahead of yourself…
I understand that cyclists often use more distant bridges but this does not diminish my point about drivers using the most convenient bridge. When even a small fraction of drivers in SE neighborhoods switch to cycling it has a significant effect on congestion. I personally eliminated 600+ yearly car trips across Hawthorne.
I don’t try to cross the Hawthorne in the afternoon from SW in a car as it currently is… the intersections downtown gridlock and the lights will just let like one car through at a time.
Maybe automotive capacity hasn’t increased partially because it was already basically at capacity.
I think that saying “because the increased demand for mobility has been borne almost exclusively by the bicycle, automotive traffic flows in this area the same today as it did in 1991.” is an overstatement based on the data presented.
I don’t disagree that building a bike lane is cheaper, I just don’t think this graph really demonstrates that very well at all, as pretty as it is. Nor does it demonstrate that without a bike lane the traffic would have gone onto the bridge in the form of automotive traffic as Geller suggests saying that increased traffic is “borne” by the bike lanes.
The Hawthorne is a pretty remarkable bridge, in a remarkable location… I don’t think data obtained from there (however convenient) is generalizable… and if this is “just an example” then what;s the point?
Let’s see more of a comprehensive “warts and all” data set. There has to be something more convincing than this!
“Maybe automotive capacity hasn’t increased partially because it was already basically at capacity.”
If this were true then you would expect an increase in traffic at neighboring bridges. According to Geller this has not happened.
It would be nice to see data that groups geographically related bridges together. For example, I would be very interested in seeing combined statistics for the Hawthorne, Steel, and Broadway bridges. It would be especially interesting if less bike-friendly bridges, such as, Ross Island, Sellwood, and Morrison (until recently) has a greater increase in vehicle trips than the bike friendly bridges. This is the kind of argument, especially if framed in minutes of commute time, that might make drivers understand how encouraging bicycling benefits everyone.
What’s not to get? Build bicycle infrastructure at reduced cost per user, and it benefits both the bicyclist and the automobile driver.
It doesn’t work the other way around…