Tag Archives: congestion

Smart highway features coming to two Chicago highways

Posted on by

A stretch of I-90 will be a “smart highway” within several years:

By 2016, the Tollway plans to install an elaborate system of sensors, cameras and overhead signs on a heavily traveled stretch of the Jane Addams Memorial Tollway (Interstate 90) between the Kennedy Expressway and Barrington Road in Hoffman Estates.

The plan is similar to, but more sophisticated than, a $45 million initiative that the Illinois Department of Transportation will implement during the next two years along the Edens Expressway and the northern stretch of U.S. Highway 41.

The Tollway plan includes installing signs with red and green signals over each lane at every half-mile that would advise motorists about safe speeds and warn of lane closings from accidents or breakdowns…

The goal is to make the Addams, which handles about 317,000 vehicles a day, “a true 21st-century, state-of-the-art corridor,” Tollway officials say.

The fiber optics and other infrastructure being installed on the soon-to-be rebuilt stretch of tollway will be able to accommodate even more sophisticated technology, which might someday automatically drive cars, officials say…

Tollway officials said Washington state’s experience with ATM has been compelling. The system is in use on I-5 in Seattle and on I-90 and State Route 520 between Seattle and Bellevue, and since 2010, the Seattle area has seen an 11 percent decrease in primary accidents and a 40 to 50 percent decrease in secondary accidents, officials said.

While highways in the United States are an engineering marvel, the lack of information about conditions on them has always struck me as a bit odd. It sounds like this new system is intended to provide information for two main purposes: warn people of upcoming obstacles which could then lead to fewer accidents and also to tell people of slower travel times so they can then make decisions about what roads to use.

Up to this point, motorists have been limited to varying levels of information:

1. You see what is front of you. Sometimes, you can spot some of these problems a long way away and get off sooner. But, too often, the line of sight is blocked and before you know it you are in a slow stretch without any alternatives.

2. Traffic reports on the radio. The veracity of these reports can vary.

3. Traffic data now available on GPS and smartphones. These seem to be generally accurate.

4. Cameras along heavily traveled routes. For example, see this set of images from cameras along I-80/94 at the bottom of Lake Michigan. This is more useful these days with smartphones.

Of course, this article also hints that this may just help set up the infrastructure to have completely smart cars where all of the information may be wirelessly passed between cars and limit the human dimension all together.

Traffic caused by the actions of individual drivers

Posted on by

Tom Vanderbilt has been talking about traffic for several years now and he highlighted again in a recent talk what leads to traffic and congestion:

Tom Vanderbilt, author of Traffic, gave a great 20-minute overview on the counterintuitive science of congestion at the Boing Boing: Ingenuity conference in San Francisco last month. Turns out a lot of the problems we ascribe to poor roads or other drivers are really our own fault. “[T]he individual driver cannot often understand the larger traffic system,” says Vanderbilt…

In fact, says Vanderbilt, traffic would be much better off if cars stayed in both lanes then merged at the very end, one by one, like a zipper. It’s safer (fewer lane changes), it reduces back-ups (often up to 40 percent), and it quenches road rage (still on the rise)…

A big reason for traffic is that too many cars are trying to occupy too little space on the road. But that’s not the only problem. A human inability to maintain a steady speed and following distance on the highway makes traffic a lot less smooth than it could be…

“You’re not driving into a traffic jam,” says Vanderbilt. “A traffic jam is basically driving into you.” He thinks autonomous cars will reduce this problem considerably...

That’s too bad, he says, because even a small drop in driving would improve congestion dramatically. One recent study of metropolitan Boston found that getting 1 percent of commuters off the road would enable the rest to get home 18 percent faster. Vanderbilt ends his science of traffic talk without suggesting ways to target this 1 percent. Fortunately there’s also a science of mass transit on the case.

In other words, individual drivers put their self-interests over the health of the entire system. So, then isn’t the trick getting drivers to recognize the larger system issues? Imagine signs at zipper merges where drivers were told to use all of the lanes – or even if this was the law. Or, if cities cut parking supply even further – this might prompt people to use mass transit more. Or, perhaps autonomous cars can really provide some solutions.

Another thought: this explanation of traffic sounds suspiciously like a sociological approach. The system is what is important when analyzing traffic, not starting with the individual drivers who will generally act in their own self-interest. New Urbanists tend to make a similar argument: roads should be designed less for cars alone, putting their interests first, and instead should make room for others like pedestrians, cyclists, and those living along the street.

Observed in Manhattan: online shopping leads to more traffic

Posted on by

A graduate student in Manhattan argues that more online shopping leads to more traffic issues on the dense island:

Consider it this way: people around the world seem to have a travel time budget of a little over an hour each day. Before the rise of e-commerce, part of that time would have been spent in the service of purchasing goods. But if that budget remains fixed, then people today may simply buy something online, then hop in a car and go visit a friend across town. In that scenario, personal travel stays constant while commercial travel increases — a net gain of people and goods on the road…

Woodard’s case studies of the Gehry and three other residential apartments in Manhattan found the answer to those questions may very well be yes. Surveying the buildings for several hours at a time in the middle of the day, Woodard found that, on average, delivery trucks stayed parked for 21 minutes at a time, and two-thirds of them were double-parked. Extrapolating the data over a full day, in the case of the Gehry, that means delivery trucks alone occupy road space that’s not a true parking space for seven full hours…

Though Woodard’s case studies were never supposed to paint an exhaustive portrait of the urban e-commerce problem, they do underscore how little is known about it. One study from way back in 2004 estimated that delivery trucks cause nearly a million hours of vehicle delay each year, but the stunning grown in online shopping since then (and the fact that companies like Amazon are reluctant to release their data) makes any precise estimate difficult. Many experts consider this process of moving freight that final mile to be one of the biggest forgotten problems facing modern cities.

At the core of the problem is street parking. In a dense urban area like Manhattan, where few buildings have the luxury of freight docks or loading zones, delivery trucks have little choice but to park at the curb. That leaves passenger vehicles and delivery trucks to duke it out for precious street-parking space, which in turn leads to double-parking, which in turn leads to general congestion.

Interesting question and findings. How much do they apply beyond Manhattan, a dense place?

One issue not addressed here: how much do commerce companies bear responsibility for this congestion? Shopping online is often viewed as cheaper and more convenient but this analysis suggests there are some hidden costs that someone has to pay for. Roads are public goods paid for with tax dollars. If they are causing more congestion, could they bear some of this cost?

Chicago tries out a “pedestrian scramble” intersection

Posted on by

Chicago has started testing the “pedestrian scramble” at a Loop intersection:

The changes center on a new pedestrian crossing pattern – dubbed the “pedestrian scramble” – that will be introduced at the intersection of State Street and Jackson Boulevard…

The test involves stopping all vehicles – heading east on Jackson and north and south on State – for about 14 seconds every other light cycle to give pedestrians a jump on traffic to cross in all directions, including diagonally, according to Bill McCaffrey, a spokesman for the Chicago Department of Transportation.

Developed more than 70 years ago, the pedestrian scramble allows pedestrians a running start to cross six ways instead of four ways.

The experiment is part of a larger plan by Chicago Transportation Commissioner Gabe Klein to reduce speeds and the number of vehicle travel lanes on busy streets in an effort to slash the number of crashes…

Klein’s strategy involves narrowing some streets, or putting them on a “road diet.’’

Two quick thoughts:

1. This reminds me of photographs of busy intersections in Tokyo where you see mobs of people crossing at all angles. See short videos here and here. Indeed, other countries have used pedestrian scrambles for decades.

2. People may not like the idea of a “road diet” but there is evidence that reducing traffic capacity could be more effective at dealing with traffic and congestion rather than continually expanding roads. Plus, you then get the side benefit of more safety and convenience for pedestrians and cyclists.

What Naperville residents like, dislike about the suburb

Posted on by

A recent survey of Naperville resident shows what they like and what they don’t about the community:

The 2012 community survey was Naperville’s first in four years, netting 1,581 responses that will be used to create a strategic plan this summer…

The survey found 91 percent of respondents were satisfied with the overall quality of life in Naperville. Looking at city services, 92 percent were satisfied with fire and emergency medical services, 85 percent gave good marks to garbage and recycling services and 84 percent were satisfied with police services. Overall city service satisfaction levels were consistent no matter which part of town the resident lived in…

Traffic flow fared the worst with only 40 percent of residents saying they are satisfied, which is a 10 percent increase from the previous survey…

Compared to the rest of the country the city scored at or above the national average in 36 of 44 areas like overall quality of city services, city streets, sidewalks and infrastructure and overall image of the community. Residents’ satisfaction with overall quality of city services rated 32 percent above national average.

The city scored below the national average in eight areas including traffic flow, public transportation and household hazardous waste disposal service.

The national comparisons are pretty interesting here. The article goes on to suggest this is due, at least in part, to effective planning and responses from the city. This is likely true to some degree; Naperville sees itself as a leader for providing efficient and effective local services. On the other hand, I wonder how much of this is due to the relative wealth of Naperville. Considering its size, Naperville is unusually wealthy with plenty of good jobs which can then lead to good schools and more money for quality of life concerns like parks, libraries, parks, and lots of retailers.

The traffic issue is a tough one to solve in Naperville. Of course, much of the suburb is made up of auto-dependent neighborhoods. Couple this with Naperville’s wealth of jobs and attractive downtown and there is plenty of driving around. The city has three highways on its edges, I-88 on the north, I-355 on the east, and I-55 on the south, but the local main streets are quite clogged. This is an issue particularly going north-south as Route 59, Washington Street, and Naper Boulevard are quite crowded. Mass transit is available to Chicago, and Naperville has two of the busiest stops in the entire Metra commuter system, but transit is limited within the city outside of some shuttles to and from the train stations. I think the real question is whether the traffic in Naperville is bad enough for residents and business to not locate or stay in the community. If a number of the other indicators are so high, I would think not but bad traffic, particularly in auto-dependent places like big suburbs, can be quite irritating.

Strong suburban reaction to a roundabout turns to praise

Posted on by

I was struck by a reaction of a few Lake County residents to a roundabout built several years ago:

When the first roundabout was proposed in Lake County, the response was extreme.

“People were so skeptical, I would seriously get phone calls from people saying there would be deaths at that corner and it would be on my conscience,” recalled Lake County Board Member Ann Maine, of Lincolnshire, who is also president of the Lake County Forest Preserve District.

More than two years after the roundabout opened at Everett Road and Riverwoods Road as an alternative to a traditional intersection, Maine said she hasn’t been stuck in a backup at the intersection and gets occasional notes from people who say they love the change.

That is quite a reaction to a roundabout and the favorable comments afterward are notable. There are studies about such things but I’m guessing those who had such a strong reaction to the roundabout either didn’t read such studies or wouldn’t believe their findings anyway. But, it is just a different way of configuring an intersection that most people get used to fairly quickly and can actually be more efficient.

An English town that got rid of its traffic signs and lights sees improvement in street life

Posted on by

This idea is not unknown but it is still highly unusual: an English town recently removed all of its traffic signs and lights.

The village of Poynton in the U.K. has undertaken one of the most ambitious experiments to date in this type of street design, whose most prominent advocate was the Dutch traffic engineer Hans Monderman. Variations on the shared-space model have been implemented in other European cities since the early 1990s, but never before at such a busy junction. Poynton’s city leaders sought the change because the historic hub of their quaint little town had become a grim and unwelcoming place…

The project didn’t come cheap, costing about $6 million. Engineers completely reconfigured the intersection at the center of town, replacing a traffic light with two “roundels” that cars must negotiate without the guidance of traffic signs. Pavements of varying colors and textures are the only signal as to which type of road user belongs where.

It was a controversial move for the community of some 14,000 people, which lies about 11 miles from Manchester in the northwestern part of England. Now, a year after construction wrapped up, a video called “Poynton Regenerated” makes the case that the shared space scheme maintains a smooth flow of traffic while simultaneously making the village center a more attractive and safer place for pedestrians, leading to increased economic activity downtown…

In the “Regenerating Poynton” video, several people who admit to having been skeptical of the plan say that after it was put in place, they came to see it as a dramatic improvement. A local city councilor says that the main street no longer seems like a dying place, as it had for years before the change. Some 88 percent of businesses in the area are reporting an increase in foot traffic, and real estate agents say they’re seeing new interest in buying property in the area.

The social interactions that result from shared space — eye contact, waves of thanks, and the like — are one of the main selling points for advocates.

What is most interesting about this presentation is that it is less about safety, and traffic crashes do tend to go down when measures like this are taken, and more about how it can improve street life. When motorized vehicles are no longer privileged on the streets in the ways that they are in most communities, street life can be more open and lively. So, perhaps we will see more people in the coming years selling this plan more as a viable redevelopment option rather than a safety concern.

Will a new design for Chicago’s Circle Interchange prove beneficial in the long run?

Posted on by

Illinois and Chicago officials are putting the final touches on plans to reconstruct the Circle Interchange where the Eisenhower, Kennedy, and Dan Ryan expressways come together. But, will a new design lead to better outcomes?

But other urban planning experts criticized the agency’s decision, saying the claimed benefits of the Circle project were not put to a rigorous test. For instance, it’s highly unlikely that IDOT’s estimate of at least a 50 percent reduction in traffic delays on the three expressways would materialize, some independent experts said.The Circle project also scored poorly on criteria designed to determine whether ridership on public transit and access to transit would be enhanced by the work, the experts said.

“The data that CMAP made available showed that this project would not produce a significant return on investment,” said MarySue Barrett, president of the Metropolitan Planning Council, a nonprofit group that promotes sustainable transportation and land-use policies…

IDOT officials insist that Alternative 7.1C would do the best job of reducing congestion, bottlenecks and crashes, leading to faster and safer commutes, according to traffic modeling that simulated the estimated 400,000 cars and trucks that travel over the Circle Interchange each weekday.

An average of almost three accidents a day occur in the vicinity of the Circle, which is also the slowest and most congested highway freight bottleneck in the U.S., according to the Federal Highway Administration.

It sounds like there are actually two conversations going on:

1. How to improve this specific stretch of road. The primary emphasis seems to be on adding lanes, both for the Kennedy and Dan Ryan through the area as well as for the congested ramps. Of course, adding lanes it not necessarily a panacea – drivers tend to fill in the supply that new lanes provide.

2. How this stretch of road fits in with larger traffic concerns in the Chicago area. It is one thing to reduce congestion at this particular point but another to improve mass transit on a broader scale that would help reduce demand for this traffic bottleneck. Traffic could be viewed as a region-wide issue where policymakers could try to reduce the number of highway trips through this area. Some would argue Americans have tended to privilege trying to fix roads rather than tackle the larger issues of why congestion occurs in the first place.

Four years of major construction is a long time to wait if the alterations don’t change much in the long run…

How much driving time is saved by the completely synchronized LA traffic light system

Posted on by

I noted the synchronization of all Los Angeles traffic lights a while back but a new piece in the New York Times describes how much time the new system is supposed to save drivers:

The system uses magnetic sensors in the road that measure the flow of traffic, hundreds of cameras and a centralized computer system that makes constant adjustments to keep cars moving as smoothly as possible. The city’s Transportation Department says the average speed of traffic across the city is 16 percent faster under the system, with delays at major intersections down 12 percent.

Without synchronization, it takes an average of 20 minutes to drive five miles on Los Angeles streets; with synchronization, it has fallen to 17.2 minutes, the city says. And the average speed on the city’s streets is now 17.3 miles per hour, up from 15 m.p.h. without synchronized lights.

Mayor Antonio R. Villaraigosa, who pledged to complete the system in his 2005 campaign, now presents it as a significant accomplishment as his two terms in office comes to an end in June. He argued that the system would also cut carbon emissions by reducing the number of times cars stop and start…

“If we reduce average travel time in Los Angeles by 20 percent, then we will see more people traveling,” Professor Moore said. “It’s money well spent, but part of the benefit is not speed, but throughput.”

These seem small fairly small changes, a few minutes for each average trip, but these would add up over time for individual drivers. Additionally, small improvements in a complex system like LA traffic could have very beneficial outcomes for the whole system.

But, as the article notes, these reduced times may not last long because more people want to drive. This is a rule of road construction: if you add lanes or improve traffic flow, more people will likely get on the road, limiting the benefits of changes. Sychronization of traffic lights may speed things up but there are larger issues at hand including the number of cars on the road and too much reliance on streets and highways to get people where they need to go.

Los Angeles “the first major city in the world to synchronize all of its traffic signals”

Posted on by

Los Angeles, famous for its roads and highways, is now leading the world in having all synchronized traffic lights.

Mayor Antonio Villaraigosa was expected to flip the switch on Tuesday on a final traffic intersection system that will result in the synchronization of all of nearly 4,400 traffic signals in Los Angeles.

KNX 1070?s Pete Demetriou reports L.A. is about to become the first major city in the world to synchronize all of its traffic signals…

Officials said the completion of this project will increase travel speeds by 16 percent and reduces travel times by 12 percent…

Signal synchronization also dramatically reduces carbon emissions by 1 million metric tons a year due to less idling at intersections, according to officials.

Less congestion and greener? Sounds like a win-win.

It would be interesting to know the final costs and logistics involved from the full project. The article suggests this project was part of the planning for the 1984 Summer Olympics but was not completed until this week. If this is such a great benefit for the city, what is stopping other cities from doing the same thing?