Recently crunched city data show the reported cyclist-motorist accident rate dropping as the number of bike commuters grows. For 2008, the most recent year for which complete data were available, the crash rate was one-quarter that of 10 years earlier. Moreover, a trend line shows a steady decrease in the crash rate even as the number of commuting cyclists more than doubled.
It would be interesting to see these crash rates for other cities, since we know mode share for bicycles is increasing in many parts of the metro. I’m not sure if they parse them out as specifically as Minneapolis does.
The Strib also quotes Peter Jacobsen from the journal Injury Prevention, but leaves out a critical sentence (emphasis mine):
A motorist is less likely to collide with a person walking and bicycling if more people walk or bicycle. Policies that increase the numbers of people walking and bicycling appear to be an effective route to improving the safety of people walking and bicycling.
About a month ago, the Governors Highway Safety Association released a report that actually said “A focus on liveable communities…may increase walking and pedestrian vehicle conflicts”, although the discussion in the report actually seems to point more towards distracted pedestrians or pedestrians being forced to walk were poor or no facilities existed.
Evaluating land use and transportation policies in terms of accessibility rather than mobility is the goal of many planners and advocates, whether they know the terminology or not. This new focus requires recognizing the interconnectedness of land use and transportation decisions.
The Texas Transportation Institute today released the final version of their report on congestion, which ranks the DC area tied for first with Chicago in hours wasted in traffic. Unfortunately, the report’s methodology completely misleads as to the seriousness of traffic, and TTI is pushing the wrong policy solutions.
The TTI report narrowly looks at only one factor: how fast traffic moves. Consider two hypothetical cities. In Denseopolis, people live within 2 miles of work on average, but the roads are fairly clogged and drivers can only go about 20 miles per hour. However, it only takes an average of 6 minutes to get to work, which isn’t bad.
On the other hand, in Sprawlville, people live about 30 miles from work on average, but there are lots and lots of fast-moving freeways, so people can drive 60 mph. That means it takes 30 minutes to get to work.
Which city is more congested? By TTI’s methods, it’s Denseopolis. But it’s the people of Sprawlville who spend more time commuting, and thus have less time to be with their families and for recreation.
Sadly, despite CEOs for Cities pointing out these methodological problems last year, TTI went ahead and finalized its reportwithout fixing them (PDFs). TTI ranks Portland as worse than Nashville, with a Travel Time Index (TTI) of 1.23 1.15 for Nashville and 1.151.23 for Portland. However, because of greater sprawl, Nashville commuters spend an average of 268 hours per year commuting, while the average Portland commuter spends 193 hours per year.
What does this mean for public policy and the Washington region? TTI’s data is often used to justify spending money on new freeway capacity, since congestion sounds bad. TTI even promotes this approach. Tim Lomax, a co-author of the report, told the Post’s Ashley Halsey III, “You can do little things like stagger work hours, fix traffic-light timing and clear wrecks faster, but in the end, there’s a need for more capacity.”
In some sense, we shouldn’t be surprised, since the report is titled the Urban Mobility Report. However, the goal of commentators and the CEOs For Cities report is to call attention to the fact that mobility (or level of congestion) alone is not an adequate means of measuring the performance of our land use and transportation systems.
On-street bike parking at the Birchwood Cafe in Seward
New American Community Survey data is out, which gives us the first look at Census Tract-level data since 2000. I pulled out some transportation data for the Twin Cities metro, and previously looked at trip-to-work mode share changes for the region. Cycling and telecommuting showed gains, carpooling and driving alone showed losses.
These small changes don’t seem that interesting, until you start to dive into the data. Since cycling gained mode share, it’s worth exploring in more detail where these gains are happening. Are the gains happening uniformly across the metro, or in specific areas? What places have the highest bicycle mode share? What do the changes mean for infrastructure and transportation planning? Attempts at answers are after the break. Continue reading →
According to new Census data from the American Community Survey, commuting to work by bicycle in Minneapolis has more than doubled since 2000. However, the data also show that between 2008 and 2009, Minneapolis saw a 10% decline in bicycle commuting. This trend does not mirror national trends in bicycle commuting, but does mirror the trend of our arch rival in all things bicycle, Portland (they were down 2% since ’08). The actual percent of commuters bicycling to work in Minneapolis in 2009 was 3.8% (Portland was at 5.8% and the nation as a whole was 0.55%).
The League of American Bicyclists has crunched the numbers on the 70 largest US cities, and has concluded that nationwide bicycle commuting rates have held steady since 2008. However, large gains have been made since 2000 and since 2005. Non- “Bicycle-Friendly Communities” (as defined by the LAB) actually saw large gains since 2000, with a 71% increase, while Bicycle-Friendly Communities only saw a 48% increase.
So why the big drop in Minneapolis since 2008? It’s hard to say exactly. Perhaps lower gas prices have lured some folks back into their cars. Another possibility is that it’s not a trend at all, but a fluke of the data. The League of American Bicyclists page does a good job of explaining all the limitations of the ACS, including a couple big ones like the fact that ACS is an estimate, not a true count and the fact that ACS asks respondents only what the principal mode of travel the worker usually used to get from home to work in the previous week. From the LAB page:
Workers were asked to list only the means of transportation they used on the largest number of days in that week. This means that if the respondent rode a bicycle to work two days but drove three, they would not be counted as a cyclist. Likewise, workers were asked only for the means of transportation used for the longest distance during the trips. If someone biked one mile to a bus stop and rode the bus for two miles they would not be recorded as a bicyclist.
The League of American Bicyclists is also quick to note that bicycling’s share of all trips is three times larger than it’s share of commuting travel. Meaning you are more likely to choose a bicycle for a trip to the store or soccer practice than you are for a trip to work.
Census 2010 data, which will give us information down to the neighborhood level, will be available sometime next year and should give a more accurate accounting of commuting habits. The City of Minneapolis is also in the midst of a new bicycle and pedestrian count, which actually counts bike riders at many locations throughout the city. While this doesn’t break down commute versus non-commute trips, it will give us another indicator of overall bicycle use in the city.
Harry Kau has developed these great commute maps which show how people are commuting to or from any zip code. The map above shows where people commute to from my own zip code, 55409. These data are a bit old, being based on 2000 Census, but the concept is still excellent.
I could spend hours clicking around the metro (and country) and looking at travel patterns. I’m relatively unfamiliar with the Census Transportation Planning Package, but it seems like a gold mine.
The idea of “road trains”, a group of cars using advanced technology to form a caravan of cars driven semi-autonomously, arose from two different sources this week.
The (in)famous Antiplanner, Randall O’Toole, touts road trains as a congestion-relief solution superior to rail building in his new book, Gridlock: Why We’re Stuck in Traffic and What to Do About It. He says building new roads is “politically difficult” and that new passenger rail construction “rarely makes economic sense”. Enter road trains. They can increase the capacity of existing road networks, according to O’Toole. He claims this technology can increase highway lane capacity by 200% to 400%.
The second source is the EU’s Safe Roads and Trains for the Environment initiative, which is actually implementing the road train concept. Cars signal their destination wirelessly to road trains already on the road, and then technology takes over to group the cars and control steering, braking and navigation. The lead vehicle, perhaps a bus or truck driven by a more experienced driver, monitors the status of the road train. When you approach your exit, your car leaves the train and you resume manual control. The EU work suggests fuel consumption for the vehicles behind the lead vehicle can be cut by 20%.
This approach avoids the large costs associated with embedding sensors in roadways to guide vehicles, and instead relies on technology within each vehicle (collision avoidance, navigation system, automated braking and steering). O’Toole puts the cost of this technology at between $1,000 and $10,000 per vehicle. I’m interested to see if his book includes a calculation of how much transit, bike lanes or other alternatives you could buy for the cost of installing this technology in all vehicles.
The benefits of this technology are numerous if it can be implemented:
A reduction in fuel consumption.
Providing the comfort and independence of an SOV with some of the efficiencies of transit.
Not having to drive. Giving car passengers back their driving time, for leisure or productivity, would be a huge gain.
I see some downsides though:
Increasing capacity on highways doesn’t equal increased capacity on city streets. This technology is perfect if every destination is adjacent to a freeway off-ramp. However, greatly increasing the capacity of highways while keeping the city streets (where drivers still have to use their puny human brains to drive) the same seems like it would equal chaos.
Equity. This “solution” to congestion puts all of the costs onto the car owner. If you think everyone should have equal access to the transportation system (and you plan your land use so that a car is almost essential), you should think about how to make this technology (which probably means a new car) affordable to everyone. O’Toole suggests “transportation vouchers”, an idea based on people making personal choices about the best transportation mode (although he really thinks there shouldn’t be any choice, the car is king). Not a bad idea necessarily, but I would suggest combining it with a true mileage tax to raise the necessary revenue. I assume O’Toole supports this idea since he says in his book review that he does not support any government subsidy to transportation.
Different cars and maintenance regimes = crashes? In all the articles about road trains, I haven’t seen any discussion about how to handle the different capabilities of individual cars. Some cars have much better brakes than others. Some cars can accelerate more quickly. People maintain their cars differently (meaning they do less maintenance). Can the technology compensate for the different capabilities of each car? Does each car “know” the distance required to stop based on its components and the condition of its parts? Bringing this technology to the real world means accommodating all kinds of cars, of varying ages, types and capabilities. Unless of course this advantage is made available only to those who are able to afford the newest and best vehicles, or we move to a uniform, government-regulated and maintained pod-car.