Eisenhower Interstate System in the style of H.C. Beck's London Underground Diagram
Via Yglesias: On Flickr (may require login) Eisenhower Interstate System in the style of H.C. Beck's London Underground Diagram
November 21, 2009
September 28, 2009
I-35W MnPass (HOT lanes) to open this week
From MPR I-35W MnPass (HOT lanes) to open this week The entire article talks about MnPass without mentioning I-394 (the link includes animations).
The interesting bit from a transportation perspective is the variable priced shoulders, and how well that works.
September 12, 2009
Timelapse USA
Driving North America, from San Francisco to DC, in 4:36 with time lapse photography (via DailyKos):
See also London to Glasgow in five minutes by train
September 10, 2009
The Economics of Road Network Ownership: An Agent-Based Approach - International Journal of Sustainable Transportation
Recently published:
Zhang, Lei and David Levinson (2009) The Economics of Road Network Ownership: An Agent-Based Approach. International Journal of Sustainable Transport Sept. 2009 3(5) pp. 339-359. [doi]
This paper explores the economic impact of alternative ownership structures on transportation system performance, social welfare, and regulatory needs. Road pricing, investment, and ownership decisions are jointly considered in an agent-based evolutionary model applicable to large networks. Results suggest that a centralized public regime with average-cost pricing is far from socially optimal with even moderate demand growth. When properly regulated, a completely privatized transportation network could achieve net social benefits close to the theoretical optimum and distribute a high percentage of welfare gains to travelers. But an unregulated private road economy would suffer from higher-than-optimal tolls and overinvestment.Keywords: network economics; privatization; road pricing; simulation of network evolution; transportation financing
September 7, 2009
Problematic plank road to be repaired
In the news ... Problematic plank road to be repaired . This road is next to the very nice Minneapolis Mill City Museum (for those interested in the history of breakfast cereal). The interesting thing is that the 6 year old road needs repairs, which is exactly why plank roads were abandoned the first time they were laid during the plank road boom of the mid 1800s. (Repairs were required too quickly, so total cost > total benefit).
Ref: J Majewski, C Baer, DB Klein (1993) Responding to Relative Decline: The Plank Road Boom of Antebellum New York Journal of Economic History
September 5, 2009
Do Americans Really Hate Flying? Or Really Love Driving?
From FiveThirtyEight: Do Americans Really Hate Flying? Or Really Love Driving?, an amateur analysis of inter-city travel statistics that includes a discussion of gravity models. The comments are worth reading as well.
August 29, 2009
Solar Roadways get prototype funding from DOT
From Autoblog (via Slashdot) Solar Roadways get prototype funding from DOT
I don't see how this could be cost-effective. 5 billion 12' x 12' panels (presumably at less than $100,000 it costs to build the prototype) still has to be pricey (i.e. it would surely be more expensive than a glass window of the same size, so we are talking on the order of $10,000). 5 billion x $10,000 = $500 trillion dollars at a minimum. Mere pocket change, less than my credit limit on my credit cards.
August 28, 2009
Determinants of Route Choice and the Value of Traveler Information: A Field Experiment.
Recently published:
Zhang, Lei and David Levinson (2008) Determinants of Route Choice and the Value of Traveler Information: A Field Experiment. Transportation Research Record: Journal of the Transportation Research Board 2086:81-92 [doi]
A major strategy of federal ITS initiatives and state departments of transportation is to provide traveler information to motorists through various means, including variable message signs, the internet, telephone services like 511, in-vehicle guidance systems, and TV and radio reports. This is relatively uncontroversial, but its effectiveness is unknown. Drivers receive value from traveler information in several ways, including the ability to save time, but perhaps more importantly, other personal, social, safety, or psychological impacts from certainty. This information can be economically valued. The benefits of reduction in driver uncertainty when information is provided at the beginning of the trip by various means is the main variable we aim to measure in this research, in which we assess user preferences for routes as a function of the presence and accuracy of information, while controlling for other trip and route attributes, such as trip purpose, travel time, distance, number of stops, delay, esthetics, level of commercial development, and individual characteristics. Data is collected in a field experiment in which more than 100 drivers, given real-time travel time information with varying degrees of accuracy, drove four of five alternative routes between a pre-selected OD pair in the Twin Cities metro area. Ordinary regression, multinomial, and rank-ordered logit models produce estimates of the value of information with some variation. In general, results show that travelers are willing to pay up to $1 per trip for pre-trip travel time information. The value of information is higher for commute and event trips and when congestion on the usual route is heavier. The accuracy of the traveler information is also a crucial factor. In fact, there do not seem be incentives for travelers to use traveler information at all unless they perceive it to be accurate. Finally, most travelers (70%) prefer that such information should be provided for free by the public sector, while some (19%) believe that it is better for the private sector to provide such service at a charge. Over 35% of subjects are willing to pay for OD-customized pre-trip travel time information.Keywords: Value of Information, Advanced Traveler Information System (ATIS), Real-Time Traffic Operations, Travel Behavior, Spatial behavior, Wayfinding Behavior, Route Choice.
August 27, 2009
INRIX National Traffic Scorecard
According to the INRIX National Traffic Scorecard, Minneapolis is the 10th most congested Metro area (for 2008, up 3 from 13 in 2007) in the US. This surprises me, as it is more congested than Atlanta, Phoenix, and Miami, (among others) which all seem worse. These numbers, compiled through GPS logs, compare with the TTI Urban Mobility Indicators, which places Minneapolis at 19 (for 2007), using data from loop detectors.
More interesting is that congestion is down ~ 20%, significantly more than VMT (which is not surprising, since we normally operate at the edge of congestion, and a drop in traffic in congested periods has a significant effect on reducing queue lengths ... no queue, no congestion.
August 26, 2009
Google LatLong: Arterial traffic available on Google Maps
Arterial traffic available on Google Maps for selected cities (including Minneapolis).
It seems they are doing it from Google Maps for Mobile, and getting automatic feedback of location from GPS-enabled online users (and thereby deriving speed). Clearly this is a good thing for traffic data nerds, and critical mass for arterial travel times is a good thing, even if Google winds up being the dominant provider.
Open House for Franklin Ave/East River Road Intersection | Bridgeland News
I attended the Open House for Franklin Ave/East River Road Intersection, where the County and consultants revealed their plans. These are described in the (what I thought was defunct) Bridgeland News article.
My views are here.
In short, instead of a Monderman-esque Shared Space, or even a roundabout, they are tweaking the signal timings and reconfiguring the approach lanes. The main change there is on the Franklin Avenue bridge, which will reduce to 1 lane in each direction on the west side, and flare to two lanes at the approach. This will no doubt improve things (in terms of vehicle delay from most approaches and pedestrian delay) over the baseline, and at least it is relatively cheap, but this, as they officials admit, is a short-term fix, and the intersection will need to be revisited post-Central Corridor.
Designing and Assessing a Teaching Laboratory for an Integrated Land Use and Transportation Course.
Recently published:
King, David, Kevin Krizek, and David Levinson (2008) Designing and Assessing a Teaching Laboratory for an Integrated Land Use and Transportation Course.
The intersection of land use and transportation policy is becoming an increasingly important focus for all urban planners. This focus, however, challenges the academic community to design effective courses that teach the concepts and professional skills required for professional experience. Integrated land use and transportation courses should engage students to develop interdisciplinary skills while becoming familiar with, for example, travel behavior and zoning policies. Laboratory courses (or segments of courses) as part of graduate curricula provide platforms to further emphasize skills. A common pedagogy problem is devising laboratory assignments that are integrative, cumulative, practical, and interesting for students. Furthermore, laboratory projects should introduce students to real-world problems and techniques while exploring broad planning themes. This paper presents uses four years of laboratory segments from a land use-transportation course (LUTC) at the University of Minnesota to evaluate the needs and results of practitioner-oriented land use and transportation planning education. The laboratory used group projects where students proposed integrated developments using air rights above existing (and sunken) urban freeways in the Twin Cities. The projects provided a practitioner-oriented project through a collaborative and reflexive learning process. This article describes the completed projects, as well as the technical skills, integrated approach and visionary planning necessary for successful execution. The students addressed complicated problems associated with large-scale development by researching neighborhood demographics, characteristics, and pertinent regulations. They used their research to analyze traffic impacts, propose zoning regulations, and outline costs and benefits from their proposal using Geographic Information Systems (GIS), statistical analyses, assessor data and traffic engineering manuals. Using the completed student projects and comparisons with other land use-transportation course and laboratory projects the authors demonstrate how these laboratory components serve multiple pedagogy goals.Keywords: Air Rights, Transportation-Land Use Planning, Education
August 22, 2009
Topological evolution of surface transportation networks
The following was recently published:
Xie, Feng and David Levinson (2009) The Topological Evolution of Road Networks.
Topological evolution of surface transportation networks
Computers, Environment, and Urban Systems 33(3) 211-223 [doi]
This study explores the topological evolution of surface transportation networks, using empirical evidence and a simulation model validated on that data. Evolution is an iterative process of interaction, investment, and disinvestment. The temporal change of topological attributes for the network is also evaluated using measures of connectivity, density, heterogeneity, concentration, and connection patterns. The simulation model is validated using historical data from the Indiana interurban network. Statistical analyses suggest that the simulation model performs well in predicting the sequence of link abandonment in the interurban network as well as the temporal change of topological attributes. The simulation model is then applied on different idealized network structures. Typical connection patterns such as rings, webs, hub-and-spokes, and cul-de-sacs emerge in the networks; the spontaneous organization of network hierarchies, the temporal change of spacing between parallel links, and the rise-and-fall of places in terms of their relative importance are also observed, providing evidence for the claim that network topology is an emergent property of network dynamics.PACS numbers: 89.75.Fb, 89.75.-k, 89.75Kd
August 21, 2009
Input Taxes, Output Taxes and Electric Vehicles.
From ArsTechnica Ford's plug-in hybrids will talk to electrical grid This is for charging the cars at the best time of day (night), but in theory could be extended to a means for charging cars for electricity different than regular electricity, in other words, a mechanism for replacing the gas tax with a different energy input tax.
Fuel (or electricity) taxes are input taxes. Theory suggests it would be better to tax outputs (actual miles traveled, by time of day and location). This would send a more direct signal to consumers about the costs they impose on the system and others. The difficulty is that this may be a much more difficult enterprise from a variety of points-of-view (collection costs, political acceptability, and even technology (GPS shadows etc.). As a second-best, input taxes are not too bad, it is better than a tax totally unrelated to usage, and the 20-30% reduction in collection costs may well make up for any inefficiencies.
July 17, 2009
Trapster
via FSJ Trapster, an iPhone application to build a and distribute a database of police speed traps. As Fake Steve Jobs says, "Fight the Power".
July 14, 2009
Dumb search engines, Dumb roads, Simple cars
From the blog Unqualified Reservations (via Daring Fireball) Wolfram Alpha and hubristic user interfaces
"... control interfaces must not be intelligent. Briefly, intelligent user interfaces should be limited to applications in which the user does not expect to control the behavior of the product. If the product is used as a tool, its interface should be as unintelligent as possible. Stupid is predictable; predictable is learnable; learnable is usable."
This applies as much to search engines as it does to transportation. Are you listening designers of ITS applications?
July 8, 2009
2009 Annual Urban Mobility Report
TTI's 2009 Urban Mobility Report (2007 data) is now out. Minneapolis St. Paul ranks 28th on the Travel Time Index (TTI, get it?), Should I be happy we are relatively less congested or unhappy that we have lost ranking? Clearly congestion is dropping in recent years.
This Space for Rent, in Broadway's Car-Free Zones
From NYT The Value of Streets for uses other than transportation.
July 1, 2009
Reflections on the Streetcar of Portland
Riding for a conference from the Portland airport to Portland State University on Light Rail Transit (LRT) and then streetcar gave me time to reflect on the Elysian Fields of transportation engineering, the Nirvana of networks and nexi.
Portland, Oregon is one of the major battlegrounds in the mode wars (car vs. transit and the internecine rail vs. bus). It has since the 1980s been held up by planners as the exemplar American city that does almost everything right. The foremost thing they do right in the view of the planning establishment is promoting LRT and bicycling.
The fascination with rail transit in particular (especially as compared with bus) was something I have never quite grokked. As a rational observer with formal training in transportation, I have had a hard time understanding the emotional relationship people have with rail. Why do people like LRT more than bus? Is it simply how we operate them, or that it is modern capital, or is there a psychological benefit associated with deterministic tracks vs. widely diverging roads? There are lots of theories on the matter, I will identify a few below.
1. Ride quality. The quality of the ride on an LRT is smoother and less herky-jerky than a bus, and passengers have a nicer facility.
2. Navigability. It is hard to navigate current US bus systems, while the fewer number of rail lines are fairly easy to figure out. Because trains cannot steer, they cannot get lost the way a bus can.
3. Speed. Trains are faster than local buses, especially if they have their own right of way and few stations.
4. Permanence. I can make a permanent investment decision based on the location of rail lines, as the transit system is committed to this line, while a bus line may be temporary.
5. Nostalgia. People who like LRT recall (or wish they could recall) the immediately post-World War II America when streetcars were at a maximum. 1946 was a magical period in US history, a boom following the long depression, when streetcar networks if not at a maximum were really close. (Coupled with a conspiracy theory about their removal)
6. Sexuality. This is part of the theory presented by Jonathan Richmond's in his book Transport of Delight and earlier paper The Mythical Conception of Rail Transit in Los Angeles. The image of the train entering the tunnel clearly evokes a primal response.
There are logical rejoinders for the first four (though not the nostalgia or sexuality argument I suppose), the most obvious is that if you spent the kind of money you are spending on rail on buses instead, and operated them better, buses would be quite nice. Navigability could be improved with a bit of thought (and trains can divert), while permanence of the last generation of streetcars (1887-1954) clearly was temporary.
The theory I have now adopted comes from my recent trip from Minneapolis to Portland accessing the airport at both ends via LRT, and then riding the Portland streetcar almost full circle. Rail transit forms an urban superstructure. Guideway transit, esp. LRT makes the city more like a single structure, and makes everything seem closer. The LRT vehicle is continuously running, and if activities are along the path of the vehicle, everything seems quite coordinated. In a way by organizing activities linearly (or multi-linearly), it simplifies the city. Hopping on a train is much like getting on an elevator.
Preferences for civilization or frontier-crossing (or degree of each) vary across individuals. Driving of course places you in a machine, but you, not civilization, are operating the machine, so just as driving is freedom, not everyone wants that freedom to drive, they may prefer freedom from driving. The extent to which you believe in the importance of community over individuals (or vice versa) will affect your perception of the issue.
( LRT may also be more popular than traditional underground subway (Metro) systems. People of course like being able to walk out the door and step onto a train more than having to descend through the gates of hell, Metro to get to the underground subterranean system. There are many reasons, not least of which is the extra time and energy required to so descend. The advantages in principle are faster point to point travel time, but that depends on the access cost vs. the in-motion speed. )
Transit invokes further passions because of the positive feedback loop between ridership, revenue, and route frequency, especially where transit is weak as in much of the US. My riding transit creates a positive externality for you (more riders, shorter headways, and more routes), so of course if you ride transit, you want to impose your preference on me. It is only selfishly rational. Further cars use scarce roadspace. While similar feedback loops may exist on the highway side (more drivers means more closely spaced roads), congestion mitigates that and the network is largely built out, so drivers do not feel the same need to impose their modal preference on the transit riding minority. Finally, drivers may benefit in the short term if other drivers take transit. (Where transit is already congested and frequent, additional riders produce few positive externalities as diminishing returns set in).
Value Capture for Transportation Finance
Our Value Capture for Transportation Finance study is now out.
Detailed reports will be placed online soon.
About the StudyLarge public investments in state transportation infrastructure--such as new freeway interchanges, highways, or transit stations--can increase the value of adjacent private land, sometimes substantially. Capturing the value of this benefit through various tools is gaining interest as a finance mechanism for infrastructure investments. But many questions remain: Does "value capture" promote or hinder economic development? How high should the tax rate be? How stable is the revenue?
To answer these and other questions, the state legislature appropriated funding to CTS to study the public policy implications of value capture.
Researchers reviewed the relationship between transportation and land values, including the measurement of benefits from a transportation improvement, as well as the legal and economic frameworks for capturing the value gains. They explored the major financing techniques associated with value capture--such as joint development of infrastructure and adjacent private parcels, rezoning and reselling, impact fees, special assessment districts, and tax increment financing--and some examples of their implementation. They then evaluated several of the proposed policies and their suitability for implementation locally, based on the criteria of economic efficiency, social equity, adequacy as a revenue source, and feasibility.
June 27, 2009
"Killed by Garbage Truck"
I noticed two people have been killed by garbage trucks in Minnesota in the past few weeks, and did a google search for the phrase "killed by garbage truck", it is not as uncommon as it may seem, or as it should be. A sampling from the first few pages of the Google search below:
- St. Paul artist killed by garbage truck 6/26/09
- 5-year-old killed by garbage truck in Brooklyn Center (Minnesota) (6/4/09)
- Man killed by garbage truck (Sydney) 4/10/09
- Downtown Worker Killed By Garbage Truck (Des Moines) 11/7/08
- Woman Killed by Garbage Truck in Dupont (bike) (Washington) 7/8/08
- Pedestrian on Farmingdale campus killed by garbage truck (New York) (5/26/08)
- NSW: Sydney Dance Company director killed by garbage truck (8/17/07)
- San Rafael man struck, killed by garbage truck in Sausalito 6/4/07
- Child Hit, Killed by Garbage Truck (Las Vegas) 1/27/07. From the article some more evidence:
In December of 2004, 19-year-old Ashley Ipock was hit and killed when a Republic truck driver slammed into the back of Ashley's mother's SUV.
In October of 2006, 3-year-old girl Ditavea Hankston was critically injured when a Republic Services track slammed into the car she was in that was stopped at a red light, crushing the back seat. Police say the driver was not paying attention and couldn't stop in time. They cited him with five traffic violations, including failure to use due care.
The child was in the hospital for two months. When she came home she could not speak, or move on her own.
- Toddler Killed By Garbage Truck (Denver) 11/28/05
- Mount Pleasant bicyclist hit, killed by garbage truck. (Charleston) (12/23/03)
I could not find a systematic database of these (which is not to say no one is tracking this, I just don't know). So the question is, are these random tragedies, or is there a systematic problem (lack of safety equipment on trucks, poor driver training, poor pedestrian/bicyclist training)?
June 26, 2009
Comments on Long-Range Funding Solutions Symposium
On June 24th, MnDOT held a "Long-Range Funding Solutions Symposium" to examine issues associated with the long-term funding of transportation. I was asked to be a discussant. These are my comments in extended form.
Thank you for giving me the opportunity to discuss the topics raised today.
First, MnDOT has identified $50 Billion of unfunded "needs" for additional resources of which 86% are for the purpose of "mobility" over the next 20 years. I am not clear as to how these needs were identified, but several points should be kept in mind. First, this is a slow-growing region (and outside the Metro a declining state). It has 5 million people now, and at best is growing at about 1 percent per year. Second, per-capita Vehicle Miles Traveled has been flat for almost a decade, and overall VMT growth has been flat for about half a decade. There are several reasons for this, most recently recession and high gas prices, but I think the most important is market saturation. if speeds are not growing (because we have maxed out the network given current technologies and face diminishing marginal returns to new road construction), and people have finite time, they choose not to devote additional time to travel (and thus distance). Fortunately, since the I-35W Bridge Collapse, MnDOT has adopted a "fix it first" approach, so that system preservation, operations, and maintenance get the largest share of the existing budget, and comprise the first funded element of needs.
We cannot know what "needs" for mobility are if we have an unpriced (or underpriced) transportation system. People will always over-consume if they are subsidized, and people do not presently pay for the congestion externality they impose on others. Once we have something like marginal cost pricing (or a second-best version thereof), we can determine which links generate more revenue than they cost to operate and maintain, and that will signal where capacity should be added, where the benefits of added capacity outweigh the costs.
Another way of thinking about what $50 billion means is that Minnesota is a state of 5 million people, so that amounts to $10000 of new construction for each resident of Minnesota (because this is above and beyond the funded part which takes care of preservation (we hope)). Over 20 years, $10000 per capita is $500 per year, or about $0.50 per trip. But that $0.50 per trip is not to pay for existing infrastructure, that is to pay for new infrastructure those travelers may or may not use; or if we were to charge users, we would be looking at 10 to 100 times as much per trip, as the new capacity built for $50 billion will serve only 10% to 1% of trips, most trips will continue to use pre-existing infrastructure.
We could also talk about mobility vs. accessibility, and why is it important to enhance mobility, but that is another long discussion, and the reader is referred to the Access to Destinations study for details.
Attention is a scarce resource, spending time on non-starters like $50 Billion in "mobility" needs detracts from real problems with existing infrastructure.
In short, the $50 Billion suggested comprises Wants not Needs. (as Jim Erkel calls it the Rolling Stones theory of transportation finance ... You can't always get what you want, but you get what you need).
Second, we need to re-examine the institutional structure of transportation funding and administration. We should consider a public utility model where a transportation authority or utility with independence from the legislation and executive branch of government determines how much is required to maintain (and as necessary expand) the transportation system, with oversight from a Public Utility Commission or similar. This would resemble how Natural Gas and Electricity and Water and Sewer in many places are currently delivered. Like those, transportation is a utility that has costs that users should bear as directly as possible. The user fee notion would be embedded into the governance structure of such a transportation authority. The British might call this a Transportation Trust. We could consider how this is organized at different levels of government (keeping state and local separate or bringing them together?)
Third, Value Capture has not been fairly characterized in the presentation made today. If we do not have road user fees, transportation creates value for land-owners. (If we do have marginal cost user fees, a closed system, and invest the revenue in transportation, making some simplifying assumptions, we would not have additional land value associated with investment (in the absence of agglomeration economies)). Since we do not have road user fees, value is created. Several of the methods proposed by the value capture study hold promise for financing transportation systematically, not just at the project level.
Fourth, in the short-term (next decade or so), gas taxes, indexed and adjusted appropriately should be used to fund transportation, as they are administratively much more efficient than road user charges. They have several advantages: foremost they are cheaper to collect than most of the proposed VMT charges. An annual odometer reading is certainly a similar alternative, but that does not have the environmental benefits of discouraging motor fuel consumption and encouraging better mileage. Ultimately as the fleet becomes electrified, the gas tax becomes a better and better incentive to move in that direction. If today 100% of the drivers use gas and pay for 100% of roads (which I recognize is not strictly the case at the state level, but is simply illustrative), and next year only 50% of drivers used gasoline, the remaining 50% would pay for all of the roads by doubling the gas tax. That provides a somewhat stronger incentive to switch to electricity. If the following year another 25% switch to electricity, than 75% use electric and 25% use fuel and pay the motor fuel tax, which is now 4 times as high. Eventually this becomes unsustainable as the last drive of a gasoline-powered car could not possibly afford 100% of the road system's costs, but in the meantime the incentive works in the right direction for the environment, and since government is always a lagging indicator, retaining the gas tax for as long as tenable should be considered the near term solution, with continuing research into road pricing, additional demonstration, and deployment of select strategies like High Occupancy Toll lanes. See Beyond the gas tax for a further discussion.
At any rate, as I have learned today, in Minnesota transit funding depends on the Motor Vehicle Sales Tax, so I will do my part to help fund transit and buy a car.
June 22, 2009
County presents scenarios for Franklin/East River Parkway remake | Bridgeland News
From the Bridgeland News: County presents scenarios for Franklin/East River Parkway remake
From the article:
"Two suggestions bordered on the Swiftian: One was a modest proposal to remove all traffic control from the existing intersection. "When those signals are out, that intersection functions fairly well," stated one man."
I was "one man".
The official alternatives are available here:
Project website
My letter (sent to the team and local public officials) clarifying what I am thinking about, which I sent to the project team is below:
Jim,Thank you for hosting the public hearing on the Franklin Ave/27th Street/East River Road intersection. I mentioned the meeting you should consider a shared-space concept (including perhaps a simple roundabout, but without all of the complex signage, separation, etc.) , the ideas I have in mind are illustrated here:
http://www.shared-space.org/
The advantage is that it could cost much less, and could be easily tested (put some covers on the signals, take down the signs, and put up some warning signs telling people upstream they are approaching a new environment, without requiring full reconstruction.
A video showing some of the ideas is here:
http://www.youtube.com/watch?v=RLfasxqhBNU&feature=related
AND
http://www.youtube.com/watch?v=wuxMuMrXUJk&feature=related(especially at 5:00 into the second video)
I recognize the idea may appear radical to traditional engineering practice, but I think it is worth giving full consideration to, especially on a site like this with no obvious inexpensive solution, with a mix of commuter and parkway traffic, bicycles, and pedestrians, a desire to minimize land taking, and a desire to calm traffic.
Please let me know if you have any questions.-- David
Finally, in addition to having a personal interest in the intersection since I use it daily, I also supervised a Master's Degree paper: Evaluation of a Roundabout at a Five-Way Intersection: An Alternatives Analysis Using Microsimulation on the intersection by Reuben Collins, which recommended a roundabout.
Unfortunately, judging by their response to comments, the study team clearly has not yet grokked the possibilities of alternatives to conventional (i.e. US standards-based) design, and intends to overbuild and oversign the location.
June 19, 2009
Rural Mich. counties turn failing roads to gravel
Via Slashdot, from the Associated Press, Rural Mich. counties turn failing roads to gravel
LANSING, Mich. (AP) - Some Michigan counties have turned a few once-paved rural roads back to gravel to save money. More than 20 of the state's 83 counties have reverted deteriorating paved roads to gravel in the last few years, according to the County Road Association of Michigan. The counties are struggling with their budgets because tax revenues have declined in the lingering recession. Montcalm County converted nearly 10 miles of primary road to gravel this spring. The county estimates it takes about $10,000 to grind up a mile of pavement and put down gravel. It takes more than $100,000 to repave a mile of road. Reverting to gravel has happened in a few other states but it is most typical in Michigan. At least 50 miles have been reverted in the state in the past three years.
May 18, 2009
China bridge collapse
From The Financial: Six killed in central China bridge collapse
Six killed in central China bridge collapse
18/05/2009 10:41 - (07:13 minutes ago)
The FINANCIAL -- BEIJING, Six people have died after a road bridge collapsed in central China's Hunan Province, Xinhua said on May 18.
The bridge, which was closed by government on May 5 to be dismantled, fell on a busy road in downtown Zhuzhou city on May 17, burying 26 cars and a bus.Another 17 people were injured and a rescue operation is underway.
Workers said the collapsed section of the bridge will be exploded on May 20.
May 12, 2009
Jockeys for hire ... casual carpooling for money
From the NYT Jakarta Journal - Finding a Detour to Earn a Living in Indonesian Traffic Jams
JAKARTA, Indonesia — When this city of epic traffic jams started carpooling a while back, it inadvertently gave birth to an entirely new profession: jockey.
For less than a dollar, car owners hire one or two jockeys to gain access to stretches of the city’s “3 in 1,” high-occupancy lanes. The jockey is essentially an extra passenger who helps commuters circumvent carpooling rules, making the ride into central Jakarta slightly less slow. ...
The difference between this and casual carpooling/instant carpooling/slugging is that here the passengers get paid (and may otherwise not travel ... though that is not clear if the jockey is a full-time or just a side job).
May 10, 2009
The Decline of Car Culture
Nate Silver on Auto Industry Statistics in Esquire.
Disentangling the long-term trend, gas prices, and the recession is tricky. Only time well tell whether this is permanent.
(The graph on the linked page is annoying because of its pseudo-3D nature, flat line graphs please with no shadows).
April 9, 2009
The Ten Most Confusing Road Signs
Via Montreal Gazette: the site "The Ten Most" has a post on The Ten Most Confusing Road Signs In America
I have personally seen #9 and #4. #4 in St. Paul (the intersection of Montreal Ave, Montreal Ct, and Montreal Way) is by no means the most confusing aspect of St. Paul street naming, which is 7th street, which takes over 8th St and then crosses 6th and the Streets. Surely it would have been easier (and more poetic) to name it Fort Road as it is farther south of downtown.
April 8, 2009
New vehicles
From Ananova: An Electric Unicycle - the Uno
From BoingBoing: Puma: GM and Segway take a swing at a small car (the comments on this article dismantle the concept quite well).
Traffic deaths last year lowest since '61
Traffic deaths last year lowest since '61
This is due both to a lower fatality rate (1.28 / 100 million vehicle miles traveled vs. 1.36 in 2007) and lower VMT due to gas prices and the recession.
The lower fatality rate is attributed by the article to seat belt use, and one has to credit safer cars and faster response times (cell-phones) and better medical treatment as well.
March 5, 2009
The solution to congestion
From Jim Foti in the Strib: Lost jobs add up to speedier commute
One might add high gas prices (and the stickiness that results when people changed behavior in response), market saturation (how much more could we travel per capita anyway), and decreased non-work travel (associated with decreased spending) as additional factor besides unemployment which are resulting in reduced VMT and congestion.
December 23, 2008
Saltless in Seattle
From Seattle Times, to improve water quality in Puget Sound: Seattle refuses to use salt; roads "snow packed" by design
November 25, 2008
Access cut off to Rock Island Swing Bridge
From the Strib: Access cut off to Rock Island Swing Bridge
A bridge once connecting Dakota and Washington Counties in Minnesota was closed to pedestrian traffic. "the double-decker structure was closed to trains in 1980 and vehicle traffic in 1999. The bridge was built in 1894." after part of it fell down. It was planned to be removed in 2010.
"Washington and Dakota counties inherited the bridge when it went into tax forfeiture after several years of private ownership."
November 20, 2008
Nurses want more traffic safety
A nice article by Jim Foti in the Strib:
Nurses urge 'ounce of prevention' on Minnesota's traffic laws
"Minnesota's refusal to pass stricter traffic safety laws earned it the second-lowest score in a new national ranking.
"The Emergency Nurses Association released its 2008 scorecard of traffic safety in a St. Paul conference room with vivid views of Interstate 94 and the State Capitol. The group is hoping to persuade the Legislature to save lives -- and lots of money -- by beefing up the rules."
...
"Despite its scorecard ranking, Minnesota generally does well in national surveys of overall highway deaths. In terms of traffic fatalities per 100 million miles traveled, for example, Minnesota had the second-lowest death rate, after Massachusetts, according to Cheri Marti, director of the state's Office of Traffic Safety."
SAT Question ... look for the internal contradiction in the logic of the Emergency Nurses Association. I.e. do those measures they advocate really save lives, or is there a kind of risk compensation going on?
E.g. Given the crash, wearing a seatbelt is good, but maybe wearing a seatbelt increases the likelihood of a crash.
November 13, 2008
Slugs' Fear HOT Lanes Will End Free Rides
From WaPo (via BJ) 'Slugs' Fear HOT Lanes Will End Free Rides
"Slugs fear that allowing toll-payers into the existing carpool lanes will tempt affluent drivers who now welcome passengers to drive solo instead. Corey A. Stewart (R-At Large), chairman of the Prince William Board of County Supervisors and a frequent slugger, last week called for an independent study of how the HOT lanes would affect the impromptu carpooling system. He also complained that the private companies planning the toll lanes have not fully addressed the questions and concerns of slugs and HOV drivers."
The right to be served by an impromptu carpool is an interesting theory.
October 27, 2008
German police seek speeding British Muppet
Via BoingBoing from Nothing To Do With Arbroath: German police seek speeding British Muppet
October 23, 2008
Congestion is still down (and Franco is still dead)
Via Mike on Traffic: INRIX Congestion Study shows congestion dropping, consistent with other data previously reported
The I-94 reconfiguration, comments from drivers
Comments on the I-94 reconfiguration (making the Riverside exit an exit only lane, dropping the fourth lane for a bit, and giving 25th Ave better entrance, via Roadguy: What a difference a lane makes
October 22, 2008
Can the speed-dial reduce speeding
By Tom Vanderbilt: I.D. - Please Touch That Dial
A nice article on the history of the design of the speedometer display in American cars, and why it might lead to speeding. There is an empirical test to be done here: Were cars with a speed dial that only went 90 mph less likely to speed (or otherwise safer) than cars with a speed dial that goes to 160, ceteris paribus?
October 16, 2008
The need for speed
From WapoProposed Road Standards Raise Safety Concerns
Apparently once progressive Montgomery County Maryland is considering requiring all new roads be built or rebuilt to a 30 or 40 MPH standard.
Perhaps they should see this creepy UK ad:
October 6, 2008
Traffic Cure Worsens the Pain
From WaPo: Traffic Cure Worsens the Pain
"So much traffic clogs Washington area roads that Cox Communications has to use 20 percent more trucks here to serve the same number of customers as in other regions. Metro has to add an average of 10 buses a year, at $521,980 a pop, just to maintain rush-hour schedules that have slipped because of congestion." ... thereby causing more congestion.
"A truck and driver stuck in traffic costs $65 per hour, according to [Giant Food] spokesman Barry Scher."
September 23, 2008
Fear of Tall Bridges
From CNN: High anxiety: Drivers fight fear of tall bridges .
The article is all anecdotal, but it is an important issue.
September 22, 2008
53% Think Driving Age Should be 18 or Older
Rasmussen Reports tells us: 53% Think Driving Age Should be 18 or Older
It would be nice if the poll (or at least the free part of the poll analysis) had asked about drinking age simultaneously.
September 18, 2008
I-35W Bridge Now Open
The Famous Bridge has now opened. At 5:10 am there is little NB traffic, but SB seems to be carrying traffic, and the bottleneck from 35W S to 94 W has already reappeared judging from traffic cameras .
(I was interviewed last night for the opening story about traffic effects on KMSP Fox 9 for the 10 am news last night, but it doesn't seem to be online).
September 16, 2008
New bridge to change traffic flow
The new I-35W Mississippi River Bridge is opening this Thursday at 5 am.
In the Strib on 9/15/08 is an article by Jim Foti: New bridge to change traffic flow , in which I am interviewed extensively (on the phone, from a QuickTrip in Iowa somewhere).
September 4, 2008
I-35W Bridge Collapse: Travel Impacts and Adjustment Strategies
A new working paper by Nebiyou Tilahun and myself on I-35W Bridge Collapse: Travel Impacts and Adjustment Strategies is out. This study was done with another study that was in the field just after the bridge collapse, and provides new information not in previous studies. The abstract is below:
On August 1st , 2007, the I-35W bridge crossing the Mississippi river collapsed. In addition to the human tragedy that it caused, the bridge failure also impacted how people moved. The bridge on average carried 140,000 vehicles daily and the failure required a signi?cant amount of traffic ?nd new routes to reach their destinations. In its aftermath travelers had to adjust their trips, requiring them to possibly adopt changes in route, mode, departure time, or foregoing some trips. Those who had to adapt were not just the ones that previously used the bridge. With the I-35 traffic using alternate routes, those who saw or anticipated higher traffic on their regular routes also found it necessary to make adjustments. In this study we ask a sample of people that were recruited for another study if their travels had been impacted by the failure of the bridge, how they coped, and what impacts it had on their other activities.
August 29, 2008
Bridge collapse didn't stall commutes, U study finds
The longer article in the Pioneer Press: Bridge collapse didn't stall commutes, U study finds -
Bridge collapse didn't stall commutes, U study finds
University of Minnesota report shows times up only slightly
By Jake Grovum
jgrovum@pioneerpress.com
Article Last Updated: 08/28/2008 11:51:43 PM CDT
A year after the Interstate 35W bridge collapse, the average Twin Cities car trip has increased by less than a minute, according to a University of Minnesota study.
The average trip before the bridge collapse was 18.6 minutes, according to the study by University of Minnesota associate civil engineering professor David Levinson. After the collapse, drive time grew by two-tenths of a minute, to 18.8 minutes.
Other studies indicate the commute time to work and back also grew only less than a minute, Levinson said.
In fact, for the majority of the estimated 150,000 motorists who crossed the eight-lane bridge daily — even those now driving in heavily-trafficked areas — the time hasn't changed much at all. Some have even seen shorter commutes, the study found.
The reason?
Despite almost 100,000 more cars using Minnesota 280 and 35,000 more cars on Interstate 94 between 280 and I-35W each day, the infrastructure in the metro area is designed to withstand those increases.
Commuters did get help from emergency road improvements after the collapse. An extra I-94 traffic lane was added in each direction between downtown Minneapolis and 280, while two intersections with stoplights were closed on 280 and most ramps were widened or modified for better traffic flow.
Levinson surveyed those affected by the collapse, monitored vehicle counts and used models to analyze post-collapse traffic.
It's not an issue of people driving less, Levinson said, because traffic levels have been steady for the past year. Despite the collapse and an increase in gas prices, the number of commutes is about the same.
Still, comparable before and after commute times might not be comforting to commuters. Prior to the collapse, the I-35W and I-94 interchange was one of the most heavily congested areas in Minneapolis.
Immediately after the collapse, two main Minnesota Department of Transportation detour sites, 280 to I-94 and Interstate 694 to Interstate 394, endured "severe congestion" and every remaining bridge crossing the Mississippi River became more crowded, according to Levinson's research, but the improvements helped accommodate motorists.
"Those made those facilities operate pretty well," Levinson said. "Had those improvements not been made, things would be a lot worse."
Not everyone is getting around so easily.
Lisa Sweet commutes from Roseville to Plymouth. She plans to sell her house and move closer to her job after seeing an extra 30 minutes tacked onto her drive.
"The commute right away was pretty tough," she said. "(Now) they're choosing to drive different ways so the traffic is spread out."
Sweet has a number of routes she uses, but some take longer than others. Those in her office have been sharing tips for navigating the post-collapse roadways, Sweet said, adding that I-694 "isn't great on Fridays."
Brian Kary, MnDOT freeway operations engineer, said commute times went "up significantly" immediately after the bridge collapse but said that after the improvements, most commute times were "comparable," particularly on I-94.
Still, Levinson's research seems at odds with a 2008 MnDOT report examining congestion in the metro area. That study found a 40-mile increase in total congested miles (a mile of traffic moving slower than 45 miles per hour) for the first time in four years in 2007, citing the bridge collapse as a reason for the "dramatic" increase.
But MnDOT expects to see "significant congestion relief" when the new 10-lane I-35W bridge is complete, according to its report, although it's unclear whether the supplemental road improvements will be permanent, Kary said.
Study finds traffic not bad after bridge collapse
Our traffic effects of the bridge collapse study made AP: Study finds traffic not bad after bridge collapse
From the Pioneer Press:
Minnesota News
Study finds traffic not bad after bridge collapse
The Associated Press
Article Last Updated: 08/29/2008 06:27:12 AM CDT
MINNEAPOLIS—A University of Minnesota study shows that car trips in the Twin Cities are less than a minute longer than they were before the Interstate 35W bridge collapse.
Civil engineering professor David Levinson looked into the Twin Cities drive times and found that the average trip before the collapse was just two-tenths of a minute faster.
Levinson says other studies have shown that work commute times are also less than a minute longer.
Part of the reason is emergency road improvements on Minnesota 280 and Interstate 94. But Levinson also says the infrastructure in the Twin Cities was designed to handle an increase.
While severe congestion occurred immediately after the collapse, traffic flow improved with the changes.
The new Interstate 35W bridge is set to be open as early as next month.
August 23, 2008
Cloud Commuting
Once upon a time, people kept their life savings on their person or at their homes, stored in physical material like gold and jewelry and property. Then money was invented as a medium of exchange, and people stored a surrogate of their wealth. Then banking was invented, and people centralized their holdings in a bank, and were paid interest for the privilege. Why were they paid? Because the banks could reuse their money by lending it out, at an even greater rate of interest. Money is fungible. I do not lose anything by storing it at the bank (and allowing them to lend it) except the privacy of keeping secret how much money I have, and risk that the bank will be unable to pay me back. The first is resolved through regulations, and the use of multiple banks, the latter by insurance. In any case, it is much safer than storing the money in a mattress at home.
Once upon a time, people kept their life's information on their person or on computers at their home or work, stored in physical material like floppy disk drives, hard disk drives, solid state drives, CDs, DVDs, and USB chips. Then the internet was invented, and centralized servers were made inexpensively and redundantly, and people could store their information in the "cloud". In many cases the cloud is free, or charges only a small fee. In exchange, the recipients agree to allow their personal information to be used to generate customized advertising targeted at them personally. But imagine their were a way for the cloud to earn interest on information much the same way banks earn interest on money, by synthesizing it and "lending it out". Since information is not rivalrous, this may prove viable with sufficient artificial intelligence aimed at developing ontologies and computer intelligence. The risk is the loss of privacy. Alternatively the customer pays the cloud for storage and computation, retaining privacy, in exchange being relieved of duties of backup, which when neglected lead to all too much data loss.
Once upon a time people kept their personal transportation near their person, parking cars and bikes at their homes, workplaces, or other destinations. This was the only way to guarantee point to point transportation in a timely way where densities were low, incomes high, and taxis scarce. Then
The tension between centralization and decentralization has been continuous through the history of technology, each has its advantages and disadvantages (and strangely, each also has religious zealots convinced there is one true way). This is ultimately a question of costs and benefits, and who bears the costs and benefits.
I am skeptical that cloud commuting can be made to work quite yet, there are still a few more technologies to perfect. Having tested Zipcar, their system lacks in several ways, much the ways the first banks failed frequently. Zipcars are still not local enough, they charge too much for lateness, the technology is still imperfect. But imagine we have cars that drive themselves. (and to PRT-advocates, these will be cars driving on streets, there are not enough resources to build a new infrastructure network for specialized vehicles). Smart cars solve the localness problem, since the cars come to you. In a way it also solves the lateness problem, because there is no need to reserve a specific car for a specific window, any unused fleet car can be dispatched. There would need to load balancing features, and maybe coordinated carpooling at peak times. (It also saves on parking, especially parking in high value areas).
Related links:
August 22, 2008
The experience paradox
From Mind Hacks: Experienced drivers perceive the road differently Experience drivers have more peripheral vision than novice drivers ... and thus are more likely to perceive and anticipate danger and adapt to changing circumstances on the road.
The problem is if we don't let drivers on the road until they are experienced, no one can get experience, unless we have really good simulators the way they do for pilots, or better yet, like in Orson Scott Card's
August 20, 2008
Should the drinking age be lowered or the driving age raised
There is move afoot to lower the drinking age from 21 back to 18. I was born in 1967, and thus was always on the window of not being allowed to drink in college at Georgia Tech while my few month older friends always could. As a consequence or nevertheless (well correlation is not causation, so perhaps I should say: in addition), I imbibe not.
Yet the logic for this drinking age always escaped me. The problem it is claimed is that driving and drinking do not mix, neither shaken nor stirred. The solution is obvious, drinking without driving does not kill innocents (generally), driving without drinking still does kill innocents. Let us raise the driving age.
Driving age is more easily regulated (you can't realistically ask an older friend to buy a car for you) and raising it will save more lives, and perhaps discourage binge drinking.
Driving is a privilege, and should be treated as such. Some will claim they need cars to get to work or wherever. This may be true for some, given how they have chosen to arrange their lives, yet somehow almost everyone survived without a private car 100 years ago. There is public transport, bicycles, carpooling, taxis, etc. available. I am very dubious about the whole concept of "I need ..." as opposed to "it would be convenient if I ..."
What is the optimal age for driving? I do not know, I would find it improbable the optimal age is 16 (though I did get my own license on my 16th birthday). Given safety rates, it might be as old as 25 for men, though there need to be rational trade-offs between value of time and value of life. Experiments in various states would be interesting to analyze as empirical evidence could help clarify the issue.
An article on the current debate is here:
Opening a Debate Over a Lower Drinking Age
August 15, 2008
US Highway deaths down by 2.5% in 2007
From AP: Highway crashes kill more than 41,000 in 2007
"By KEN THOMAS, Associated Press Writer
Thu Aug 14, 11:26 AM ET
WASHINGTON - Traffic deaths in the United States declined last year, reaching the lowest level in more than a decade.
Some 41,059 people were killed in highway crashes, down by more than 1,000 from 2006.
The fatality rate of 1.37 deaths for every 100 million miles traveled in 2007 was the lowest on record, the National Highway Traffic Safety Administration said in its report Thursday.
California had the largest decline, 266 fewer fatalities than the previous year. The largest percentage decreases were in South Dakota and Vermont.
North Carolina's death toll increased the most in the nation, up 121 over the previous year. The District of Columbia and Alaska had the highest percentage increases.
Motorcycle deaths increased for the 10th straight year. There were 5,154 motorcycle deaths last year, compared with 4,837 in 2006."
One wonders what's going on in North Carolina.
August 14, 2008
Cop cams, safety or revenue?
From McClatchy (again via Boing Boing) Cop cameras don't just catch speeders, they raise cash
There should be an equilibrium between level of enforcement (both frequency/coverage of enforcement and the associated fines) and maximum revenue, just as between level of enforcement and maximum safety. These two equilibria however are likely not equal. Formulating this model would make a good Ph.D. written exam question.
August 13, 2008
U.S. Driving Continues to Decrease
From the Wall Street Journal U.S. Driving Continues to Decrease
"Rural travel has fallen 4% since late last year, while urban driving is off just 1.2%"
August 11, 2008
Bureaucracy
A fabulous post (and good comment section) from Megan McArdle: The Pennsylvania Department of Transportation: Sheer genius
regarding her trying to get a driver's license and being held up for a suspended license for underage drinking before she had a license.
The really interesting thing is that underage drinking is against the law in the US primarily because we are concerned about drunk driving (drink driving to those from the UK). She did not have a license then, they just waited for her to apply for one before assessing the suspension, 16 years later, long after she ceased to be underage.
July 31, 2008
Evaluation of the Transportation Effects of the I-35W Collapse
The latest draft of the Evaluation of the Transportation Effects of the I-35W Collapse paper is now online.
Comments are welcome.
July 28, 2008
Evaluation of the Transportation Effects of the I-35W Bridge Collapse
The Nexus group webpage bringing together our ongoing and completed research on the I-35W Bridge collapse is available here. Evaluation of the Transportation Effects of the I-35W Collapse
Note in particular, several reports (links near the bottom of the page) which document the effects of the bridge collapse, reproduced here:
Zhu, S, D. Levinson, H. Liu, and K. Harder (2008) The traffic and behavioral effects of the I-35W Mississippi River bridge collapse (under review)
Xie, F. and D. Levinson (2008) Evaluating the Effects of I-35W Bridge Collapse on Road-Users in the Twin Cities Metropolitan Region (under review)
He, Xiaozheng, Saif Jabari, and Henry X. Liu (2008) Modeling Day-to-day Trip Choice Evolution under Network Disruption (under review)
AASHTO Releases Bridging the Gap Report
AASHTO, the organization of state DOTs, released a report on the "restoring and rebuilding the nation's bridges": Bridging the Gap (pdf)
HTML version here
Bridge over I-35E begins to crumble
From Strib: Weather, age eroded 35E bridge
"The 6-foot-by-9-foot-by-1-inch patch that peeled off could be described as a veneer for the underside of the steel beams that span the length of the bridge and support it, Dorgan said. Those beams are structurally unaffected by the loss of concrete, he said."
If the aesthetics (i.e. veneer) distract from function (that is, it falls on cars), perhaps bridges should be strictly functional.
July 25, 2008
I-35W Bridge Collapse Transportation Effects
We have posted some preliminary results from the traffic analysis of the I-35W Bridge collapse here: Evaluation of the Transportation Effects of the I-35W Collapse. The reports are near the bottom of the page. These are currently under review and comments are welcome.
July 21, 2008
Paving over paradise just got more expensive
From the Pioneer Press: Asphalt shortage raises the price of roadwork
Not only cannot we not afford new roads because DOT revenue is down, we cannot afford them because prices are up.
Asphalt, which is made from petroleum byproducts, is seeing its material costs go up, as well as the costs of transporting the stuff.
"Tom Ravn, acting state construction engineer for MnDOT, said the asphalt supply issue affects six to eight highway projects under way around the state and could force a monthlong delay on one of them. Ravn wouldn't say which one. He said he's fielding calls from concerned contractors and studying the state's options, from granting delays to possibly lowering the asphalt grade it requires, among other things."
Lowering the grade presumably means the road will have to be repaired more frequently or replaced sooner.
Still, as the websites say:
http://concreteisbetter.com
http://asphaltisbest.com
(Grammatically if there are only two choices, concrete may be better, especially since no one has registered http://gravelisgood.com )
July 12, 2008
Queue jumping or zipper merge
Kenny Bellew complains about Late Merging on the highway
From one point of view this is simply cheating or queue jumping. From another, this is an efficient use of highway space.
Imagine we have a scenario where 2 lanes merge into 1 (i.e. left lane closed ahead, merge right, or vice versa). What privileges the drivers of either lane to have first dibs on the scarce road space downstream.
Further, if the drivers can move through the queue at the same rate (vehicles per hour) independent of where the merge occurs, why should the queue be longer rather than wider?
If in fact the queue is longer, it may create more unsafe driving conditions (differential speeds in the two lanes), and block exit ramps, thereby delaying people who are using the road but want to exit upstream of the bottleneck.
I suspect a zipper merge (one from each lane) is more efficient, and what we need to do is to retrain drivers to take turns when merging into a queue, rather than play games as is common now about trying to jump queues, or not letting cheaters in.
In fact, this is MnDOT's current preferred strategy Motorists reminded to use zipper method to merge during single-lane traffic on Highway 61 bridge at Hastings
July 2, 2008
Fake speed bumps
June 28, 2008
Machine Fecundity
From Kevin Kelly's blog: The Technium
"A while back George Dyson sent along this note about the fecundity of manufactured items:
I had to park my car at [Seattle's] SeaTac on Saturday-Sunday and this sparked a small epiphany. It now costs more to park a car at one airport than to rent one at the other end. To my twisted mind, this indicates that machines (taking the automobile as a benchmark) are now self-reproducing so fast we have reached a transition point where machines are cheaper than the empty space they fill."
June 17, 2008
ICFTI 3
UPDATED August 27, 2009.
I am leaving today for Paris, where I will be presenting a paper at The 3rd International Conference on Funding Transport Infrastructure. We hope to have the 4th conference in Minnesota next summer.
The paper is:
Levinson, David and Andrew Odlyzko (2008) Too Expensive to Meter: The influence of transaction costs in transportation and communication. Philosophical Transactions of the Royal Society A: Mathematical Physical and Engineering Sciences 366(1872) pp 2033-2046 [doi]
Abstract. Technology appears to be making fine-scale charging (as in tolls on roads that depend on time of day or even on current and anticipated levels of congestion) increasingly feasible. And such charging appears to be increasingly desirable, as traffic on roads continues to grow, and costs and public opposition limit new construction. Similar incentives towards fine-scale charging also appear to be operating in communications and other areas, such as electricity usage. Standard economic theory supports such measures, and technology is being developed and deployed to implement them. But their spread is not very rapid, and prospects for the future are uncertain. This paper presents a collection of sketches, some from ancient history, some from current developments, that illustrate the costs that charging imposes. Some of those costs are explicit (in terms of the monetary costs to users, and the costs of implementing the charging mechanisms). Others are implicit, such as the time or the mental processing costs of users. These argue that the case for fine-scale charging is not unambiguous, and that in many cases may be inappropriate.
Betting on VMT
A site called Long Bets takes bets on the future, an interesting one: The U.S Department of Transportation Bureau of Transportation Statistics (www.bts.gov) will report a lower number of total highway vehicle miles traveled in 2010 than in 2005.
It was made in 2005, and thus far the prediction may hold.
Is Minneapolis Ready for GOP Convention?
From Newsweek, an article on the Convention and the I-35W Bridge, Bridges: Is Minneapolis Ready for GOP Convention?
John Hourdos and myself are quoted on page 2.
(I know, the article headline asks if Minneapolis is ready for the convention when it will be in St. Paul).
June 15, 2008
Memo to the Next President of the United States on Transportation Policy
I have drafted a Memo to the Next President of the United States on Transportation Policy.
The memo outlines ten visions, which are summarized here, for fuller discussion, see the full memo:
- Within eight years more cars sold in the United States will be powered primarily by electricity and bio-fuels than by fossil fuels. All buses and passenger trains will use electricity or bio-fuels.
- Within eight years Americans will be able to ride autonomous smart cars that drive themselves in mixed traffic.
- Within a year, an independent federally-funded Bridge Inspection Service will begin to inspect and publicly report on the quality of all bridges on the National Highway System.
- After thorough evaluation, within eight years, bridges and pavements on the US Interstate Highway System will be upgraded to handle trucks carrying up to 100,000 pounds, increasing the efficiency of the trucking industry and by reducing the number of vehicle trips, increasing safety for other road users. These improvements will be paid for by the trucking industry, which directly benefits from the improved system. In heavily traveled corridors, a system of truck-only toll lanes will be constructed.
- Within eight years American travelers can choose to travel congestion-free by car or bus through America's largest metropolitan areas.
- Within four years American travelers will enter airports and transit, and train stations and cross borders, passing both security and immigration controls without delay while ensuring security.
- Within eight years a new source of transportation revenue based on time and place of use will be deployed, replacing the federal and state gas tax. This funding will support highway and transit networks.
- Returning to the vision of Democratic President Andrew Jackson, items in federal transportation legislation that do not serve a national purpose will be vetoed.
- Extending the bipartisan efforts of transportation deregulation in the late 1970s and early 1980s, within four years, highway and transit services and infrastructure will begin to be competitively provided by independent (public, private, or non-profit) organizations under appropriate local or federal oversight. Infrastructure will be provided under a public utility model, ensuring quality of service in exchange for earning a rate of return.
- Within one year, the United States federal government will establish separate capital and operating budgets. This will be coupled with a federal program to guarantee loans and bonds for highway and transit infrastructure projects.
Full memo after the jump
Continue reading "Memo to the Next President of the United States on Transportation Policy" »
June 7, 2008
Road Builders advocate increase in gas tax
Road, transportation builder: America stays in the slow lane
'“The presidential campaigns are not focused on this, but we need to change the conversation. The other countries are not waiting for us. They’re surpassing us,? Ruane said, noting China plans to build 53,000 miles of new highway in the first two decades of this century compared to just 1,130 new interstate miles here.'
Comparing China to the US in terms of road construction is clearly a strawman argument, the US already built a huge network, ours is mature, the B/C ratio for new links in the US is much lower than China. China has yet to build out its network.
The strategy for maturity is not more of the same.
Asphalt costs too much
According to USA Today, the rising price of oil has led to a hike in asphalt costs, which means less repair can be done for a fixed budget: Oil prices seep into asphalt costs, detour road work: Repair projects are a blow to budgets
This should make the concrete people happy, as asphalt loses marketshare.
June 4, 2008
7 Bridges
1. August 1, 2007: I-35W
2. January 2008 Hastings Bridge
3. March 20, 2008 St. Cloud Bridge
4. March 26, 2008 University of Minnesota Pedestrian Bridge
5. April 25, 2008 Lowry Avenue
6. May 6, 2008 Blatnik Bridge (I-535) in Duluth
7. June 4, 2008 MnDOT barricades Hwy. 43 bridge over Mississippi River at Winona
(post updated: Blatnik and Hastings added 6-6-08)
May 31, 2008
Private roads vs. Google Streetview
A Minnesota town with private roads,
North Oaks tells Google Maps: Keep out - we mean it, the story from the Strib.
Google maps has apparently complied, judging from the lack of Streetview in the neighborhood.
Interesting bits are that roads in the town are a club good rather than a publicly provided one, so to drive without permission is trespassing. Google's car which collects streetview data apparently did that.
May 30, 2008
IBM Commuter Pain study
IBM released a study on commuting ... IBM Press room - 2008-05-30 IBM “Commuter Pain? Survey Focuses on Fuel Spending Limit, Frustration and Sleep Deprivation - United States which has gotten an article in newspapers in every city they studied.
The executive summary is here
It should be noted that compared to "ground truth" (i.e. other better done surveys) their results are biased toward participants with longer than average commutes. One also has to question the methodology that simply raised the price and asked whether people would change.
Minneapolis-St. Paul had the least pain of the surveyed cities, but it should be noted it is also the smallest metro area of those surveyed.
The local article is here
May 28, 2008
The end of traffic and the last man
On Talking Points Memo The Last Traffic Jam ... as has been widely reported, total traffic has been decreasing (presumably related to the rise of gas prices and the onset of economic slowdown or recession). The article also includes a nice excerpt from Time c. 1947.
If the trend continues (-4.3% traffic growth per year), we may soon be out of a job.
May 8, 2008
Can a bridge be rebuilt too quickly?
April 23, 2008
Does alcohol lubricate Putnam's social capital?
Minnesota ranks among worst in DWIs, study shows
"Minnesota has one of the nation's worst drunken driving rates, said a government report that says 15 percent of adult drivers nationally report driving under the influence of alcohol in the previous year. Here are the states with the worst records:
1. Wisconsin, 26.4 percent
2. North Dakota, 26.4 percent
3. Minnesota, 23.5 percent
4. Nebraska, 22.9 percent
5. South Dakota, 21.6 percent"
Note, these are also almost exactly the states with the highest social capital according to Robert Putnam's index (see the book Bowling Alone)
Table 4.1 Social capital scores by state
Rank State Score
1 North Dakota 1.712
2 South Dakota 1.693
3 Vermont 1.424
4 Minnesota 1.325
5 Montana 1.296
6 Nebraska 1.157
7 Iowa 0.988
8 New Hampshire 0.779
9 Wyoming 0.6710
10 Washington 0.6511
11 Wisconsin 0.5912
12 Oregon 0.57
(Source: Putnam 2000)
(Kevin Krizek and I discuss Putnam's social capital idea in the book Planning for Place and Plexus
This raises the interesting question: does alcohol lubricate Putnam's social capital?
From a social perspective, drinking alone at home may be better than drinking away from home. But what do I know, I am a teetotaler.
April 16, 2008
Patenting Roads
As I was thinking about a new road design, I found a number that had been patented. The idea of patenting a road may seem a little strange, but it has happened a number of times. In very few cases have the patented designs become widely used. Some references below:
Traffic intersection - Patent 3915580
Simultaneous left turn vehicular intersection - US Patent 5795095
Traffic interchange - US Patent 5921701
Some additional prior art cited in patents above:
1173505
February 1916 - Hale
1515251 November 1924 -Graves
1543080 June 1925 - Graves
3107590
October 1963- Cedeno
3272097
September 1966 -
Gazis et al.
Burrell
3915580 October 1975 - Kaufman
4592673
June 1986 - Lee
4630961 December 1986 - Hellwig
5049000 September 1991 - Mier
April 15, 2008
Stillwater Bridge stuck again
Stillwater Lift Bridge is up, but when's it coming down?
From the article in the Strib:
"McFarland said that the lift bridge getting stuck "has happened a lot. It's an old bridge. You kind of expect this.""
Gives one lots of confidence in Minnesota's infrastructure.
April 10, 2008
Construction Season
An article in the St. Cloud Times announces the 2008 MnDOT construction program, including replacement of the DeSoto Bridge.
The state list includes 135 projects
The Metro area list is given in the Pioneer Press
April 7, 2008
Confidential Records Program Plates = No Tolls
Special license plates shield officials from traffic tickets
"Muir discovered that drivers covered under the Confidential Records Program abuse the system by evading toll road charges, running red lights at intersections with red light cameras, parking illegally, and breaking other traffic laws with impunity."
March 25, 2008
Calvin and Hobbes: Dad Explains Science
March 24, 2008
Speed limits for mode shifts
From the Telegraph:
15mph speed limit to force people out of cars
The UK is planning a series of 15 new "eco-towns". As part of their design, a 15mph (Britain is not consistently metric) speed limit in the heart of these new towns hopes to discourage auto use, in stark contrast to the older new towns (Stevanage to Milton Keynes) which made freeflowing traffic a centerpiece.
Too much compliance
From Freakonomics: Your City Needs You to Blow Through Red Lights
Apparently too much enforcement induces too much compliance, so there is not enough revenue to pay for the enforcement. There must be an equilibrium between revenue and compliance.
March 23, 2008
Lane Reversal: Diverging Diamond Interchange
I heard this a few years ago, and going through old notes, decided to post, from the CBC series: As It Happens
To listen: Real Audio file, go to minute 21m:20s
The introductory text: "For as long as most of us can remember, the citizens of North America have been firmly entrenched on the right. Now, a bold and shocking proposal in the state of Ohio may result in a wild shift to the left. And it will come as no surprise that the French are involved.
The Ohio Department of Transportation is currently mulling over an unprecedented traffic diversion. If a recent recommendation comes to fruition, drivers on U.S. Highway 224 may find themselves driving -- if only briefly -- on the left side of the road. The lane-reversal plan is a proposed import from the city of Versailles, France, where Gallic drivers have found it to be "la rue juste"."
This is a clever idea to avoid left-turn conflicts (or at least put them where you want them and make the crossovers seem like through movements. Wikipedia has an article.
My former classmate, Joe Bared, now at FHWA did a study with colleagues:
TechBrief: Drivers' Evaluation of the Diverging Diamond Interchange, FHWA-HRT-07-048
The Hwy 224 proposal in Ohio was rejected. The proposal for Kansas City seems alive.
March 22, 2008
Random Roads
Via Amateur Ramblings From Weburbanist, some more cool photos: 7 Urban Wonders of the World: Amazing and Record-Setting City Roads and Streets
DeSoto Bridge in St. Cloud closed
MnDOT has closed the DeSoto Bridge in St. Cloud:
From MPR: Officials weigh next steps for the DeSoto Bridge
From Pioneer Press: St. Cloud Minnesota 23 Over The Mississippi River / New DeSoto Bridge given a top priority
From Strib Replace St. Cloud bridge? Or repair it?, complete with the quote from the local State Senator:
"State Sen. Tarryl Clark, DFL-St. Cloud, hopes that a replacement bridge can proceed with some of the speed that's been the hallmark of the 35W bridge reconstruction. State funding is available, federal help might be possible and a design-build process could be used to speed things up, she said.
The Hwy. 23 bridge is a major link not only for St. Cloud but also for the state, she said. Much of the bridge's traffic comes from outside the local area, she said, and if it takes several years to get a new crossing, "I don't know how the community is going to make it.""
(Perhaps St. Cloud will cease to exist?)
and from the local paper, a more interesting discussion: The St. Cloud Times:
Plans in Work
Note the discussion of earmarks for a related bridge. And the problems when trying to use that earmark money (two of three bridges would be closed at once). Why the federal government would even consider allocating funds to a state highway remains puzzling (from a normative, not a positive, point of view).
March 21, 2008
Incomprehensible Intersections
Via Digg: If you ignore all of the annoying advertising, there are some really cool intersection photos here:
Incomprehensible Intersections
and here:
March 6, 2008
Experiment recreates field observation
From New Scientist Shockwave traffic jam recreated for first time.
Yes, when a car taps its brake and a road is at capacity, shockwaves ensue. Yes not all drivers are identical, and yes some drivers are random. Candidate for Ignobel prize?
In real life, we don't drive on circular test tracks, and there are gaps, allowing traffic to eventually recover. One could have looked at race cars for a similar experiment.
February 3, 2008
Using GPS Mobile Phones as Traffic Sensors
Another study on Using GPS Mobile Phones as Traffic Sensors, this from Berkeley. See earlier Transportationist post for some discussion of this. Also see Evaluation of Cell Phone Traffic Data, a study underway by my colleague Henry Liu.
February 2, 2008
A camera to catch HOV lane cheaters
From the Evening Standard: Camera that can catch lone drivers in car-sharing lanes.
This has always been a difficult problem for authorities, as enforcement has in the past required human eyeballs. Researchers have experiment with infra-red to determine the heat profile inside the car, but that was apparently problematic. But in the home of the panopticon, cameras (with appropriate recognition systems) will be able to identify the number (and apparently race) of passengers in the vehicle.
January 4, 2008
GPS is imperfect
Another one of those fun stories about how following GPS can ruin your day (or your car) (via Engadget): Man follows GPS directions onto train tracks, into dummy hall of fame
January 3, 2008
Drivers on Cells Clogging Traffic
From the AP: Study: Drivers on Cells Clogging Traffic
In addition to being a hazard, it seems drivers using cell phones also slow down traffic. I wonder if this delay is offset by the faster response times to incidents because cell phones are ubiquitous.
December 15, 2007
Central Corridor on Washington Avenue
In response to letters from the President of the University of Minnesota, former U of Mn Regent, Peter Bell, currently Chair of the Metropolitan Council now endorses Central Corridor on Washington Avenue at grade.
Now maybe someone will seriously consider getting private cars off of Washington Avenue if it is such a safety and congestion trap (which of course it would be were cars, buses, trucks, light rail, pedestrians, and bicyclists trying to simultaneously use that space). The price would be much lower than a tunnel (some paint, some bollards, and a "Do Not Enter" sign for starters).
Think about it this way, construction is effectively going to close Washington Avenue to traffic anyway for some period of time, just keep it closed.
This not too technical link might help some university officials rethink the issue.
From Induced Demand to Reduced Demand
OR
Effects of Roadway Capacity Reductions.
The I-35W Bridge collapse provides another example. 140,000 trips crossed the Mississippi River Bridge before the collapse, according to MnDOT's Nick Thomson (presented at a seminar at the University of Minnesota), only 90,000 can be accounted for on other crossings.
Should Washington Avenue really be carrying traffic through campus? Should campus have a major thoroughfare in its midst?
December 12, 2007
No Left Turns
From NYT (via Slashdot) Left-Hand-Turn Elimination UPS is trying to eliminate left-turns, which typically have more delay (and thus fuel consumption and air pollution) than through or right-turn movements. This of course should be true primarily at permitted rather than protected lefts, it wasn't clear from the article whether UPS has signal timings in its database.
November 28, 2007
A substitute for GPS
From Techcrunch: Google Mobile Maps PinPoints Your Location Without GPS
This technology uses cell phone towers (and triangulation) to locate you. While not as perfect as GPS, it should be useful for general navigation, especially with added algorithms to smooth out the jumpyness. It is an idea long speculated on (in the transportation community see: this article by my late colleague YB Yim for a review and this for one of the earliest papers on the idea. ) that is finally seeing commercialization.
November 14, 2007
Tunes from the road
From the Guardian, via Slashdot: Japan's melody roads play music as you drive
If you drive at a fixed speed the road will play a tune via grooves cut into the pavement. One can envision this as a way to get drivers to stick to the speed limit, though surely there are more practical means.
November 7, 2007
Google at the gas pump
From Ars Technica: Google at the gas pump translates to happy motorists, retailers.
So getting lost will be less common, since maps will be more available. Whether these will be printable was unclear. Of course there are about 180,000 gas stations in the United States, so this is at best an experimental, first stage deployment, but it might be deployed more quickly than GPS with mapping software in every vehicle.
November 4, 2007
DARPA Urban Challenge Results
Via The Register:
Carnegie Mellon wins the robotic Urban Challenge
October 28, 2007
Speeding and the monopoly of force
Two articles on speeding, one from Techdirt about how GPS can dis-prove a speeding allegation:
GPS Tracking: Drivers' New Best Friend?
The second from the New York Times about police over-enforcement and beating (stemming from alleged traffic violations) leading to a drivers' rebellion in Russia.
Weary of Highway Bribery, Russians Take on Police.
They are both rebellions against extortion, one extortion has a slightly greater veneer of legitimacy (it is the state seeking the payoff rather than the individual officers), but in the end it is the state's monopoly on the use of force as Max Weber put it, that enables this practice.
(Yes of course, speeding is wrong, but wrongful enforcement is also wrong).
October 16, 2007
No groundbreaking for bridge
MnDOT made the right decision by avoiding a groundbreaking ceremony for the I-35W bridge ...
Ceremony for new bridge skipped - Minnesota Daily
Will there be a "ribbon cutting" though?
October 10, 2007
Oberstar Forum: Cost of Frugality
The Oberstar Forum on Transportation Policy and Technology: The Condition of Our Nation's Transportation Infrastructure: Heading Toward a Crisis? was held this past Sunday and Monday. The CTS website advertises the public Monday session, but there was a double-secret, super private, unadvertised, invitation only session attended by the elites in the transportation community (i.e. I was invited). These private sessions are more interesting in that there is less speech-making and more discussion, though one can hardly say there was no speech making. In fact, I gave a talk on the Cost of Frugality, which I have posted.
The New I-35W Bridge
MnDOT unveiled plans for the new I-35W replacement bridge day before yesterday... Interstate 35W Bridge in Minneapolis, MN, The main distinction in alternatives seems to be which way the piers are oriented. I think the best you can say about it is that it is unimaginative, but probably better looking than what went before. One never can truly visualize the bridge until it is complete, but I am not optimistic. There are opportunities to do interesting things in the space along the water under the bridge, Sydney does some great things under highway bridges there. It is not clear if those opportunities will be taken, but that is something that can be done later.
Clearly MnDOT missed the boat on the opportunity to use airrights over the bridge for some positive good (in addition to avoiding snow removal and de-icing costs) which is too bad, but not surprising.
Nevertheless, I am amazed that if Aesthetics/Visual Quality amounted to 20% of points available for technical evaluation, that something so mediocre will be built though.
October 4, 2007
Counting you in your car
From the Washington Post: Infrared Scans May Regulate HOT Lanes. The latest technology used to detect cheaters in HOV/HOT lanes.
(1) Hopefully they won't throw out this data after its collected (see previous post on LA), it does have valuable planning uses in predicting mode utilization.
(2) Any semblance of privacy you thought you had is gone, hopefully we can watch the watchers just as easily as they watch us. David Brin's Transparent Society is interesting in this regard.
(3) The amount of effort we go to in order to enforce minor rules is amazing. In the absence of congestion on the HOV lane, (and the presence of congestion in the general purpose lanes) it is actually efficient for there to be some small amount of cheating: it takes a car out of the congested lanes, puts it in the uncongested lanes (without congesting them) and produces a net benefit to society. Too much clearly would congest the HOV/HOT lanes. It reminds one of the expression "A Puritan is someone who is deathly afraid that someone somewhere is having fun." The point isn't that it is costing society to have some cheating, the point is that "free riding" is cheating and "unfair" whatever that means.
October 2, 2007
Can you say megaproject ...
As with many large infrastructure projects, the estimated cost of the I-35W replacement bridge rises and rises. How come public officials never over-estimate initial costs? (Perhaps a question for my Transport Policy class).
Articles from the Strib and PiPress:
Sticker shock: Bridge tab soars by $143 million
October 1, 2007
L.A. doesn't save data on traffic growth
From the front page of the LA Times web page, an article on traffic counts!: L.A. doesn't save data on traffic growth
"But although the sensors and computers collect massive amounts of data about traffic patterns and congestion, they do little to help engineers plan for the city's growing transportation needs -- or determine how development is affecting traffic.
That's because the city does not save the information for more than a few days, using it only to direct traffic in real time by adjusting the speed at which lights turn from green to amber to red."
This is true elsewhere (Minneapolis e.g.), and a damn shame. I have been in meetings about this, but people are frugal and the beneficiaries are in different departments/units than those who would do the work.
September 28, 2007
Gravity-challenged
From the Strib: Nick Coleman: Let's call 'em 'faith-based bridges' -- pray you get across
Coleman (Nick) gets it right.
September 27, 2007
'After bridge fall, engineers worry about undue alarm"
After bridge fall, engineers worry about undue alarm
"State highway officials around the country want the government to stop scaring the public by using dire-sounding phrases such as "structurally deficient" and "fracture critical" to describe bridges in need of repairs."
Perhaps they forgot a bridge fell down. This occurred in part because there was *not* enough attention to bridges. Perhaps scarier terms are useful here. Certainly the real problems should rank worse than the non-problems, but the previous problem of under-investment has not suddenly disappeared. As the average age of bridges increases, the likelihood of collapse also increases in the absence of rehabilitation.
Modeling themselves on car dealers ""Car dealers no longer have 'used' cars. They instead switched to 'previously owned.' Can't we similarly come up with nomenclature that is less of an issue?" Minnesota said in its response." is hardly reassuring. People hardly hold car dealers in high regard.
August 30, 2007
Canada's Crumbling Infrastructure
From CBC (via Zvi) Montreal mayor wants inspection reports for private buildings. It seems our neighbor to the north has crumbling infrastructure too. This is somehow reassuring (if it can happen to Canada it can happen anywhere, so it's not anything "we" did or didn't do), on the other hand it suggests there is no easy example to point to, if only we did like "so and so" we wouldn't have these problems.
Awareness of crumbling infrastructure is like a virus (whether the infrastructure itself is crumbling because of some contagion would be an interesting scientific hypothesis, but doubtful).
"I-35W bridge collapse could produce U of M traffic headaches"
From today's Minnesota Public Radio: I-35W bridge collapse could produce U of M traffic headaches ... I am interviewed and the blog gets a mention.
August 29, 2007
I-35W bridge collapse - What happened on August 1st and after
One of the interesting scientific questions that emerges from the tragedy of the I-35W Bridge Collapse is how traffic responds. There are several time horizons for looking at this.
Most immediately are those who are on the link leading up to the bridge. MnDOT's traffic cameras show the cars turning around on the freeway within seconds of the bridge collapsing, before the dust clears literally. "Video footage of the collapse from Mn/DOT traffic camera 628. 6:05 p.m., Aug. 1, shows an edited two-minute clip from a traffic camera at the south end of the bridge. Initially, the camera is pointed to the south away from the bridge. When traffic comes to a stop, the camera pans to the north where the bridge has just collapsed. (wv file)". This is a rational response on the part of drivers who don't know what else may collapse. As my wife says, there are two types of people "those who run towards the meteorite and those who run from it". Survivors are those who ran from it.
Over the next few minutes and hours, word of the bridge collapse spread. My student Shanjiang Zhu has organized MnDOT's loop detector data into a movie that shows the 15 minute traffic counts on all the loop detectors in the Twin Cities, comparing that number with the previous Wednesday's count at the same time of day. Blue indicates lower volumes, red higher volumes. Clearly after the collapse, people heard quickly through various sources (cell phone, variable message signs, radio, etc.), and avoided large swaths of I-35W in the vicinity (which turns blue) and complementary feeder links, while competititve substitute links (Mn 100, I 35E, parts of I-94) saw an increase. We still have to compute how overall traffic volume and Vehicle Kilometers Traveled changed.
Once people were informed, on subsequent days people searched for alternatives. The alternative the first day for some was to avoid driving, but that quickly changed, and different routes became natural substitutes. A second movie compares the counts on the 15 days after the collapse with the average of the previous 8 weeks same day of week (so a Thursday is compared with the eight pre-collapse Thursdays). This illustrates the changes network wide. The
movie is available.
Finally, there may be some longer term adaptations, but we don't have enough information only one month into the changed situation to know about this yet. With colleagues Henry Liu and Kathleen Harder, we have obtained a National Science Foundation Small Grant for Exploratory Research to look at all of these issues in some more depth.
Zipcar
Prior to leaving for London we sold our second car to cash up for the trip. On return, we had two children, two drivers and one car. As I usually walk to work, this is normally fine, but on occassion one has offsite meetings. For this
Zipcar has several locations on campus at the University of Minnesota where they keep cars. For a fixed fee, I get the opportunity to rent cars from Zipcar with a minimum of paperwork and contracts. I can reserve the car online (assuming it is available, which may turn into a problem if demand is high) and then can rent the car for $8 per hour plus tax. This sounds expensive, and requires planning, but in exchange I avoid all the fixed costs of auto ownership.
I am issued a Zipcard, which I swipe over the keyhole on the car I reserved, and electromagically, the car door unlocks. The key is in the car. I am responsible for fueling, parking etc., but presumably Zipcar takes care of maintenance and insurance.
Using the car yesterday went quite smoothly once I figured out the operation of the Zipcard in unlocking the door (it sounds obvious, but isn't quite, and didn't work immediately, though did a second time), and getting out of the garage (which requires the use of the parking garage contract card, which is in the car, but is again not obvious if you have not done so before.
Otherwise, the car was where it was supposed to be, ran fine, and I have had no problems with the experience.
The only problem I foresee is if demand outstrips supply, renting on-demand may become difficult. Zipcar could add vehicles to the fleet, but there may be some lag on this. However, like many network industries, the more members, the more valuable, as it will then be available in more places, and my likelihood of getting a car when and where I want will be easier.
August 18, 2007
China Bans Reporting on Bridge Collapse
In today's WaPo: China Bans Reporting on Bridge Collapse - washingtonpost.com
"Communist authorities have banned most state media from reporting on the deadly collapse of a bridge in southern China, with local officials punching and chasing reporters from the scene, reporters said Friday."
Apparently physics works in both communist and non-communist countries; but a free press only in non-communist ones.
I 35W Bridge repair
Article from today's Strib: Phone call put brakes on bridge repair
"Plans to reinforce the bridge were well underway when the project came to a screeching halt in January amid concerns about safety and cost."
August 14, 2007
Chinese bridge collapse kills 22
From BBC: Chinese bridge collapse kills 22
August 2, 2007
I-35 W Bridge Collapse, some initial thoughts
The I-35 W Bridge over the Mississippi River in Minneapolis collapsed at 6:05 pm CDT last night. The Strib reports: 9 dead, 60 injured, 20 missing after dozens of vehicles plummet into river
This is of course a tragedy for those directly involved. I myself was driving under the bridge earlier yesterday with family. Fortunately that was 3 hours earlier, and everyone in my immediate family is safe. It is of course shocking to think about this bridge that I have traveled hundreds of times (about 2 miles from my house) collapsing. Having just returned to Minneapolis about 36 hours ago (I was actually going to say something nice about Northwest Airlines), this was not the welcome I was seeking.
I have some random thoughts below,
== Network Effects ==
What will be the effects of the collapse on traffic?
Networks are complex things. MnDOT has suggested using the roughly parallel MN-280 as a bypass, and have (temporarily?) converted the road to a freeway by turning to green the only traffic light on the road (why was the light never replaced earlier?)
There are other possible substitutes, that MnDOT and the local neighborhoods will not want to encourage as bypasses. For long distance trips, the I-494/I-694 beltway, US-169, Mn 100, and I-35E will one suspect get additional traffic. (hypothesis #1).
For shorter distance trips, traffic that would have gone down I-35W may divert to Mn-280, Broadway to I-94, or Snelling Avenue (which is a limited access highway for a good stretch, and should be immediately have its traffic signals retimed to accommodate additional traffic)
It might take some time for a new equilibrium pattern of traffic to re-emerge. It is still summer vacation period, so the University of Minnesota has not started a full fall semester, and traffic levels are relatively low, giving some change to adjust. The day after Labor Day will be another time to test.
As a result of this however, some other problem sections of road may no longer be as problematic. The merge from I-35W sb to I-94 wb should not cause problems for instance (hypothesis).
There might be interactions with the Crosstown reconstruction, as that is also discouraging traffic from using I-35W a few miles south. It might make more sense now to consider just closing all of I-35 W so they can do the reconstruction faster (assuming closure would make it easier to do the construction under the current design).
== Reconstruction ==
Some recent bridge collapses (I-580 in the Bay Area) were remedied quite quickly. I think this will be longer. First it is a much larger bridge. Second, it will clearly require redesign, as the first design failed for "unknown" reasons (as opposed to a a truck exploding, which may not be worth defending against).
== Structures ==
I am not a structural engineer. This report by my late colleague Bob Dexter is interesting
http://www.cts.umn.edu/Publications/ResearchReports/reportdetail.html?id=617
Fatigue Evaluation of the Deck Truss of Bridge 9340
Robert Dexter, Heather O'Connell, Paul Bergson
March 2001
Report no. Mn/DOT 2001-10
Of course the abstract, while noting problems with the design,it said "As a result, Mn/DOT does not need to prematurely replace this bridge because of fatigue cracking, avoiding the high costs associated with such a large project." This was published 6 years ago , probably finished 7 years ago, and things change. Reports in the news media say the bridge was structurally deficient. We still don't know what element of the bridge failed first, or if the construction on the bridge had any role (one suspects it does, but that is still speculation).
== Politics ==
(1) Allocation of resources to new facilities rather than repair and maintenance.
This is a classic problem in transportation funding. Ribbon cuttings on new projects are much more politically "sexy" than maintaining what we have. People are also more interested in road surface than the underlying structure. Yet pavement failure, while bad, is not nearly as bad as structural failure. "Failure" in the traffic level of service sense, while economically costly and personally annoying, and perhaps leading to more (or at least different) crashes, does not have anywhere near the same connotation as structural collapse.
(2) Vetoing the gas tax
Minnesota Governor Tim Pawlenty recently vetoed a legislature-passed increase in the gas tax that could have raised money to repair bridges like this one. The latest gas tax would not have solved this problem, but previous taxes that were not passed (due in part to Pawlenty's previous veto threat) may have, had the money been spent on this kind of thing.
(3) Pointing fingers
It is too soon to say "J'accuse". Most people will probably want to wait for rescue and recover operations to be complete, and then for memorial services, and then for a more thorough investigation. However, MSNBC was starting early speculating in which direction the fingers would wind up pointing.
(4) Funding the stadiums
Minnesota is in the process of building 3 new stadiums (Twins, Gophers, and eventually the Vikings). Is this the best use of local funds? Hopefully this will be a shock to the system.
== U of Mn ==
Keeping with the University of Minnesota tradition, classes will go on today as scheduled. Classes were cancelled on 9.11, but that happened the same day.
== Crisis vs. Opportunity ==
Rebuilding the bridge is of course a crisis, but it is also an opportunity to do something interesting. I speak in particular of air rights. A bridge over the Mississippi is expensive. But imagine having a 2 or 3 story office building hanging from below, or built above the highway. A view of the river from offices is probably among the best in Minnesota. It will not impair other's view of the river especially much, and would generate a significant amount of revenue to pay for reconstruction.
An example would be the historic London Bridge, which had houses and stores along the side, encroaching on travelways. There are better ways to combine transportation arteries with development opportunities, and creative design can show the way.
July 13, 2007
Point trading
From The Times (via Techdirt) Pensioners take cash and points to keep speeding drivers on the road
"It is the latest ruse on the roads of France: drivers are avoiding disqualification by trading licence points on the internet.
Complete strangers are taking the rap for speeding offences in return for up to €1,500 (£1,000), and police admit they are powerless to intervene. Even pensioners who have not driven for many years are getting in on the act."
Basically since the speed camera cannot see inside the vehicle, and the violation goes with the driver not the car, people can lie about who was driving. Whoever said the French were insufficiently entrepreneurial?
July 6, 2007
Vehicle-to-Vehicle
From BBC: Connected cars 'promise safer roads'.
To be valuable, this must work in a mixed environment. Not all cars will have communication devices reporting to them, and even cars with such devices might see them disabled from time-to-time. Communication between cars is fine, but the key to the future of smart cars is the ability to sense the environment independently, and operate in that perceived (rather than reported) environment. Only that can be deployed.
Consider the first year when only a small percent of cars will have the technology. If the system requires all the cars to have the technology, who will pay extra for it? If it requires no other cars, but adds value, people may buy it.