Renewing the National Commitment to the Interstate Highway System: A Foundation for the Future

We are looking forward to the American Traffic Safety Services Association (ATSSA) Midyear Meetings. https://www.atssa.com/Events/Midyear-Meeting  They will be held next week (August 21 to 23) in San Diego. There will be many topics of interest including the joint working group with the Automotive Safety Council discussing automated vehicles and how their systems will communicate with work zones and a new Traffic Signals working group meeting to form a new division in ATSSA.

Not on the agenda, but sure to be another topic of conversation is a document recently published by the Transportation Research Board (TRB) titled, “Renewing the National Commitment to the Interstate Highway System: A Foundation for the Future (2019).” This report was requested by Congress to facilitate their discussions on the future of highway construction, maintenance and most importantly, funding.

Download a copy of the report HERE.

The report begins by looking at the history of the national highway system, then examines the needs for current and future maintenance and expansion and the funding problems of the trust fund. Finally, it offers a “Blueprint for Action” including these 10 recommendations:

  1. Congress should require a new program to rebuild and revitalize our existing highway system.
  2. They should work with states to “right size” the highway system, adding capacity where needed to meet developing demand.
  3. FHWA should work with states to assess the structural integrity of existing pavements and use that to decide when full reconstruction is more cost-effective than repaving.
  4. These improvements should be paid for by immediately raising the federal fuel tax to cover the federal share of the investment in renewal and modernization.
  5. Congress should allow states and local agencies to toll existing roadways as a way of helping them pay their share of these improvements.
  6. To avoid future funding shortfalls due to changes in technology, Congress should prepare to change from a per gallon fuel charge to a miles-driven or other user-based system.
  7. A new database of pavement conditions should be developed and combined with new modeling software to help make better decisions regarding the roads that should be improved.
  8. Begin preparing for connected and automated vehicles by learning what they will need in terms of roadway safety infrastructure including pavement markings signs, and temporary traffic control devices.
  9. With the goal of a more resilient highway system, assess the potential threats to our roadways from climate change and extreme weather and determine where improvements to our roads should be made.
  10. Recommend ways of reducing greenhouse gas emissions.

As Congress works once again on a new highway bill, this document is sure to be a part of the discussion. Most of these 10 recommendations fit nicely with ATSSA’s efforts to improve roadway safety. Familiarize yourself with these recommendations and include them in your next conversation with your elected representatives!

Innovate.ATSSA.com

As most readers will know, I’ve been involved in work zone ITS for nearly 20 years now. So I assume most people are aware of the technology and aware of the availability of studies, best practices, specifications, and more. But one should never assume, especially in a discipline where new practitioners are arriving every day.

This was hammered home to me in a phone conversation yesterday. A fellow contractor complained about a state that just let a project with a work zone ITS spec that no one can meet. Another person on the call told a similar story about an engineering firm.

This is compounded by the fact that those not in our industry don’t know where to begin their research. For that reason the American Traffic Safety Services Association (ATSSA) has created the “go-to” website for work zone ITS. You will find it within their Innovate.ATSSA.com website at: http://innovate.atssa.com/work-zone-its.html

This website was just introduced to members in February. It is still new so we are adding resources every day. But because it is new, you can be sure that everything there is current and the best information available.

On the ATSSA website you can learn about new technology, you can search for projects by state, and you can view upcoming industry events where you’ll be able to learn more. There is a blog area where you can read this and many other work zone ITS – related blogs. And most important there is a large section devoted to news and resources. Check it out today!

Variable Speed Limit Webinar

Variable speed limits systems have always, at least intuitively, promised benefits for work zones including greater throughput, reduced speed variance, and as a result, fewer crashes. We discussed these systems in a post in October 2015 after a presentation at the National Rural ITS meeting in Utah. The concept made sense and we looked forward to greater use of VSL systems.

A webinar was just offered April 4th by the US DOT Office of Assistant Secretary for Research & Technology entitled, “Variable Speed Limit Systems – Are They For Everyone?” The speakers, and there were several of them, did a great job of explaining the advantages and disadvantages of these systems. Those speakers included Jimmy Chu of FHWA, John McClellan of MnDOT, Bryan Katz of Toxcel, Jiaqi Ma of Leidos, and Vinh Dang of WsDOT.

There wasn’t a lot of new information. Instead they presented a comprehensive history of VSL systems from around the country. They looked at different uses for these systems, including work zones. In all, more than a dozen different projects from 9 different states were discussed. Some projects were relatively small, and others like those in Minneapolis and Seattle, were quite large.

But in almost every case, the results of these systems have not met expectations.  This was true for weather related systems, work zones, and congestion management applications. Reductions in speed variance and crashes were very small if not non-existent. And the reason in every case was a lack of conformance by the traveling public. There was some smoothing, but very little.

Many of the system designers anticipated this and included variable message signs alongside the VSL signs to explain why the speed reduction was justified. But drivers either misunderstood when they were supposed to slow or simply chose to continue at their current speed until they saw the problem for themselves.

Law enforcement is critical for these installations. Without enforcement, compliance will never reach levels that will result in the benefits designers expected. But law enforcement often became distrustful of the data they received, or didn’t get timely notifications at all. They also ran into serious resistance from the courts. So enforcement slowed, and compliance tanked.

There is still hope that these issues will one day be resolved. But for now, variable speed limit systems just aren’t providing the benefits we all hoped to see.  The webinar closed with a short discussion of future considerations. One thought was to combine these systems with a larger big data process (as discussed in our last post). They might look at not just weather, or work zone conditions, but also at traffic speed and volume data approaching the area, timing of major events, and more to improve drivers trust of VSLs.

Another thought was with regard to automated vehicles. Will VSL systems be more effective when the information is sent directly to each vehicle? If a pop-up display recommends slowing to 35, will they be more likely to do so? Or will they continue to ignore them as they apparently do now? Once autonomous (driverless) cars are on the road, the recommendations from these systems will be adopted automatically. But until then, compliance will remain the biggest problem for VSLs.

Why Aren’t Queue Warning Systems Used On Every Project?

Those of us that have been in the work zone ITS industry for several years understand that agencies don’t change quickly. New technology must be tested and evaluated before it is used on a more regular basis. We get that. But we are now at the point where queue warning systems should be included on every project where frequent and dynamic queuing is expected.

WZcrashesStudies by the Texas Transportation Institute have shown a reduction in rear end crashes of as much as 45%. Crash severity is reduced as well. Other states including Illinois have also seen a dramatic decrease in crash frequency and severity.

These systems are inexpensive and the benefits are substantial. Avoid just one lawsuit by using queue warning and that savings will more than pay for the cost of the system. So it does not matter how long the project lasts. Projects lasting only a few days could deploy a system for something like $700 per day.Projects months long would pay something like $10,000 per month. Those prices include the sensors, message signs, communications costs, design, set-up, etc.

One law suit will cost tens if not hundreds of thousands of dollars.  It really is that simple. And that doesn’t take into account all of the other benefits. Fewer crashes mean the project is completed faster. Motorists are happier with the DOT because they aren’t experiencing long delays. And you will have the data to meet the Federal Work Zone Safety & Mobility Rule requirements for work zone performance measurement.

There has been progress. Texas is moving toward statewide use of queue warning systems. Illinois is also. Several other states are working on following suit. But most states only use them on special high impact projects. Some don’t use them at all.

So, I really do want to know. What is holding you state folks back? Why don’t you use these everywhere? I sincerely want to know. Please comment on this post. Let’s talk about it. Perhaps as a group we can find ways around the road blocks you face. And together we can significantly reduce the single largest cause of work zone fatalities nationwide.

Portable Traffic Signals as Work Zone ITS?

20160623_065843Today there are many definitions of work zone ITS. I’ve always felt that just because a device is controlled by electronics and some amount of internal software, does not qualify it as work zone ITS. Good examples are portable changeable message signs or portable traffic signals. In their simplest form they work independently and do not react to their environment.

But recently we started a project with portable signals that should qualify. Before the job bid we suggested portable signals as a cost-effective alternative to hardwired temporary signals mounted on posts and powered by a generator. The agency agreed but asked for most of the optional features mentioned on Horizon’s website. Those included wait time display, drive way assistance device, emergency vehicle preemption, and remote monitoring and notification.

Let’s look at each of these in a little more detail.

The wait time display is a changeable message sign attached to the articulating arm of the signals. When the signal at the other end of the work zone is green, the one facing stopped traffic tells it the maximum time they can expect to wait. Then, once the signal on the other end goes to red, it displays a countdown to green equal to the remaining clearing time.

This is a great feature when the work zone is especially long or when drivers on one end of the work zone cannot see the other end. Like travel time systems, once drivers know what the wait time is, they don’t seem to mind it as much. But not knowing often upsets them.

20160623_065949The driveway assistance device is another clever addition. The display consists of a red light and two flashing red arrows, one pointing right and the other left. When the light is red, drivers are expected to stay put. But when the right arrow is flashing, they can turn right when it is clear. The device ties into the signal phases on the main line. The system knows when traffic is moving to the right and tells the driveway assistance device to inform any drivers there that they may do so, too. It’s similar to a WAIT FOR PILOT CAR sign, but starts the moment traffic is cleared to go in that direction.

Emergency vehicle preemption is the same as most permanent signals use. It immediately turns the signal on the other end red, but still must give the same clearance time before turning to green for the ambulance or fire truck. Because these signals are farther apart, sometimes a half mile or more, the emergency responder must still sit there until traffic clears. Otherwise the potential for conflicts exists. This is one feature I would not recommend again, except when the signals are set up for a conventional intersection where clearing time is minimal. Or when there is an especially high volume of traffic that would otherwise extend the green time without preemption.

Remote monitoring is just what it sounds like. The signals report to a server over a wireless digital modem. All aspects of signal operation are monitored. If a lamp fails, or power drops, or communications between signals are lost; an alarm is sent to everyone concerned via text or email. Signal operations are also logged with each phase date & time stamped. So if a motorist claims they were green when they were actually red, the agency would be able to prove that.

Traffic engineers have taught drivers to expect traffic signals to do certain things. Portable signals can now do anything that permanent ones can do. That reinforces those lessons and makes our work zones safer.

Adapting Existing Technology to Unusual Traffic Problems

The work zone ITS industry has produced many creative ways to help mitigate the impacts to traffic from work zones and to protect workers from that same traffic. But often the problems we solve aren’t the same ones we set out to address. This is true for most industries when they encounter new technology.

According to author H. W. Brand it was true for the movie industry as well. When the first “talkies” were released, “Sam Warner (of Warner Brothers’ fame) convinced his brothers to purchase a technology that allowed the attachment of sound to recording film.” “The initial appeal was that sound would permit theaters to dispense with the orchestras that played accompaniment to otherwise silent films.” Today we can’t imagine movies without the sounds of explosions, gun fire, and, of course, dialogue.  But they were focused on the economic benefits of the technology and so missed what we all see as the obvious artistic advantages.

The same is often true in our industry. Our technologies are more mature now, though new ideas are introduced every day. But too often we miss good opportunities to improve the safety or efficiency of our roads because we don’t have a prepackaged system ready to deploy.

In fact, we do have them ready. We just don’t think it through far enough. Most of our systems use sensors to measure traffic flow, then compare that data to a set of rules, which then trigger outputs like messages to message signs, or alarms at a traffic management center. So it does not matter what your traffic concern is, a system can probably be created to address it. And while such a system could be called “custom”, it won’t normally be saddled with the costs and lead times normally associated with custom systems.

Redding Map

A good example was a demo project done for Caltrans a few years ago. They were closing one of their busiest ramps in Redding for reconstruction. The plan called for them to send traffic to alternate ramps. But no one of those was capable of handling the volumes at the closed ramp. Road-Tech proposed a simple solution. A sensor was placed on each of the alternate ramps. And portable changeable message signs directed traffic to the best alternate. As traffic backed up on the first alternate ramp the sensor detected the stopped traffic. That caused the system to change the message signs to recommend the second alternate ramp. If that ramp backed up traffic was sent to a third alternate ramp.

It was simple, inexpensive, and worked very well. The only problem encountered was public outreach efforts scared everyone away. So the volumes were never as high as expected. But this does show what can be done with the tools we already have. No one talks about alternate ramp systems. But it turns out we had one ready to go. We just didn’t know it.

Next time you are faced with a traffic problem, try to imagine a rule. That rule would say, “If traffic does X, make Y happen.” So if traffic slows I want to change the message signs to warn of STOPPED TRAFFIC AHEAD. Or if average traffic speeds exceed 75 MPH, I want to send an alarm to the police department. If you can come up with a rule, a solution is probably already available. Keep that in mind and you’ll be surprised what can be done!

The State of the Work Zone ITS Industry

We are starting a new construction season so I thought it would be a good time to review our progress as an industry, look at where we stand today, and talk a little about prospects for this coming year.

2015 was an important year for all of us. It was in 2015 that we began to get good hard data to support the value of work zone ITS. The Texas Transportation Institute led the charge with their My35 queue warning system research. Their data is not final, but it is clear that use of a queue warning system has reduced end of queue crashes by as much as 45%. It has also significantly reduced the severity of the crashes that do still occur. We have always known these systems are effective. Now we can prove it.

Illinois DOT has shared data from work zones on a stretch of interstate under construction two years in a row. The first year a queue warning system was not used. The second year one was used. In that second year the work zone was in place for a longer period of time, yet they saw far fewer end of queue crashes just as they did in Texas.

This data will result in much greater use of end of queue systems. Another effort that is helping is the Every Day Counts initiative from FHWA. They just completed webinar number 12 of the Smarter Work Zones series. This focus on proven work zone ITS and how to deploy it has done wonders to promote these life saving technologies. You can view any of these webinars now at: https://www.workzonesafety.org/swz/webinars/ .

More good news came on the procurement front. Agency design folks have passed up work zone ITS in the past because they didn’t know how to write it into their construction bid documents and didn’t have the time to figure it out. But now states like Texas, Iowa and Illinois have shown us the way with innovative on-demand contracts for queue warning systems. This allows the traffic operations folks to use these systems when and where they are needed. Including systems in large jobs still makes sense, but this on-demand method allows far greater use on smaller jobs where traffic impacts were not clear before the job was let. Many other states are now adopting this model including Indiana, Michigan and North Carolina.

As more and more states begin to use work zone ITS, the resulting data can be used to prove the value of these systems once again. And that will push even more states to follow suit.

In the meantime, we are seeing help from another, unlikely source: the autonomous vehicle industry. Discussions at autonomous vehicle events between their designers and work zone ITS practitioners have shown great potential for collaboration going forward. They now understand they need to know where work zones are located in real time and they are interested in how we can help them do that. Don’t be surprised if we hear several big announcements on this subject in 2016!