Work Zone ITS and Data Sharing Services

wazeOn January 2nd iCone announced a new data-sharing partnership with Waze.  Waze, as you may know, collects travel time data from its users and then shares it with them. Users may also note special problems like work zones or crashes as they travel. They even note the prices at individual gas stations.

Waze already shows the work zones reported by state DOTs. But now any work zone equipped with iCones will also show up. After all, not all work zones are reported. And not all that are reported actually take place. Better yet, they will appear as soon as the work begins, and they will disappear as soon as the work ends, making this truly real-time!

This is important for one simple reason. As work zone data is generated by our systems, it quickly overwhelms the DOTs. Most systems offer a live feed to the DOT but only a very few DOTs have incorporated that data into their DOT travel time systems. Portable work zone system data stands alone and apart from permanent systems. So it is not reaching Waze or Inrix or any travel time system. And that means it is not reaching the end user.

This new partnership skips the intermediate step and supplies the data directly to Waze. Users will begin seeing the benefits right away, rather than years from now. Drivers will become more aware of work zones and many will bypass them altogether. In both cases work zones become safer, and our roads more efficient.

Read the press release HERE.

Learn more about Waze or download the app HERE.

Improving the Effectiveness of Smart Work Zone Technologies, Part 1

illinoisstudyA brilliant study was published in November by the Illinois Center for Transportation Studies entitled “Improving the Effectiveness of Smart Work Zone Technologies.” The principal researchers were Yanning Li, Juan Carlos Martinez Mori and Daniel Work. Download it here.

It is brilliant for a couple of reasons. It moves past the studies we conduct over and over again that look at the effectiveness of smart work zone systems. Those have been done, and there really isn’t much more to be learned from additional studies. We know they work. It has been proven. Enough said.

Instead, this study looks at ways of making something good, even better. There is so much new information is this study that we will discuss it in two separate blog posts. This first one will look at their conclusions regarding sensor types, sensor spacing, and missing data. The second will consider travel time estimation and, in particular, their recommendation of the Kalmar filter algorithm.

Let’s begin with sensor types. The study focuses primarily on doplar and side-fire (RTMS) sensors.  They compared the advantages and disadvantages of each and concluded that for most work zones systems there is no advantage to RTMS type sensors. The RTMS provide more accurate flow measurements than radar due to fewer occlusion issues. But they do cost more and are more difficult and time-consuming to set-up and configure. They wrote the, “analysis indicates the types of sensors do not have significant influence of the performance of existing smart work zone systems. It is suggested the choice of sensor types should depend on the specific requirements and constraints in each work zone.”

They went on to say that given the extra cost of RTMS, you are normally better off spending that money on additional doplar sensors, as more sensors improve the data quality far more than the sensor type. Of course, if lane by lane counts and classifications are needed to meet the deployment goals, RTMS is the only practical solution.

Next they discussed sensor spacing. Most of us in the work zone ITS industry suggest sensor spacing of between 1 mile and one-half mile apart. This study confirms what we learned through experience. They said the closer you place your sensors to each other, the better the data quality. “When more sensors are deployed, the systems provide faster notification of changes of the traffic conditions and increase the estimation accuracy of the traffic conditions.”

However, anything closer than a half mile apart provides negligible additional benefits. “When the sensor spacing is smaller than 0.5 mile, the benefit of additional sensors … is marginal.”

A third topic they covered was missing data records. This has not been covered in any detailed way in previous studies. But it is important. They studied only two projects but for those projects found they were missing as much as 10% of the data records. They did point out that the system messages continued to be sent to the message signs. But what if the interruption was sufficient to delay those messages?

One vendor suggested the data records were missed due to the cellular carrier dropping them in favor of voice transmissions. If true, this underlines the need for redundant communications. Satellite backup or better cell service is a must. If data is dropped for more than a few seconds it could affect the timeliness of warnings to traffic upstream. And if that data will also be used for work zone performance measurement, it causes additional problems. A measure of system data transmission performance should be included in the evaluation of every work zone ITS deployment.

So, in short, simple systems with more sensors are better than more complicated ones.

Spacing of a half to one mile is best. Anything greater quickly loses accuracy and anything less is not cost-effective.

And agencies should require a data transmission reliability report to be sure that most of it is getting through, even during major incidents.

In a future post we will return to this study to examine algorithms, especially for travel time systems. In the meantime, download this important study!

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 Illinois Model for Procurement of Work Zone ITS

Yesterday I had the pleasure of sitting in on yet another Smarter Work Zones webinar from the Every Day Counts folks. This was lucky number 13 in this wonderful series and looked at procurement of work zone ITS. You can download the recording in a few days at:

Early in the webinar an attendee, Charles Martin, made a statement in the chat box that I thought helped focus the discussion. I believe he once worked for Maryland SHA and that experience and perspective showed through when he said, “I find that the most complicated issue to determining how to fund adding SWZ’s often it is not one project driving the need, but rather several. One may have Fed-aide, and others may not. (N)one of the projects may have funding to add ITS.”

The webinar that followed may not have answered his concerns completely, but it did offer several innovative options that should work in most situations.

Todd Peterson of FHWA began by giving an overview of procurement methods and explained that the best option depends on the type of work zone ITS you plan to use. Jerry Ullman of Texas Transportation Institute (TTI) ran through the different contracting methods that three states (Massachusetts, Texas and Iowa) have used and shared some lessons learned. Finally, Matthew Daeda of Illinois DOT went into detail on his state’s approach and that’s what we will talk about today.

Illinois uses a two level approach to procurement of work zone ITS. For larger contracts and longer term projects they try to identify the need as early in the process as possible. This is usually accomplished as a lump sum line item in the bid documents. Details regarding the types and quantities of devices are included in the special provisions. When they know they will have serious traffic impacts, they include WZITS and other mitigation strategies in the bid documents.

They will also add WZITS under change order when impacts are greater than expected. Again this is done with the same language they use when it is included in the bid.


But for smaller projects and short duration traffic impacts, they are now using an on-call contract. Each district advertises a bid for this on-call service. Districts 1, 8 and 9 already have three year contracts in place. Districts 2, 3 and 5 have or will soon have contracts in place. Districts 4, 6 and 7 will follow suit very soon. The on-call work zone ITS is paid for using HSIP funding.

These on-call contracts are intended to provide queue warning for projects with a duration of two weeks or less. In District 1 (Chicago) and 8 (St Louis) the vendor supplies 4 changeable message signs and 4 sensors. In more rural District 9 the vendor supplies 1 changeable message sign and 4 sensors. Each district adjusts the quantities to fit the needs of that district. District 9 includes rates for monthly rentals. Districts 1 and 8 only include daily and weekly rates.

This contracting method offers several advantages:

  1. The state only pays when the system is needed.
  2. They work directly with the vendor and that greatly improves communication.
  3. Staff has direct access to the system data and to make changes.
  4. By bidding for each district local companies are more likely to win, thus reducing response time.

Mr. Daeda offered several lessons learned. He said that one vendor installed software in their TMC that did not work well with their firewall. In the future he would like to require vendors to install and test any software before getting a notice to proceed.

He would like a pay item for supplemental devices. Then he could add more sensors or message signs when they are needed.

When deployments run over a month, they currently pay for a month at the monthly rate and for additional days beyond that at higher daily and weekly rates. Mr. Daeda wants to change that going forward to be at a percentage of the monthly rate once the system has been out for more than a month.

Matthew plans to clarify language regarding relocation of devices. And there have been times when he wished he could add camera trailers.

In our last blog post, “The State of the Work Zone ITS Industry”, we talked about the many ways in which 2015 was a landmark year. This webinar is a perfect example of that. These EDC events just keep getting better. The speakers were all on topic and very professional. The webinar service worked without interruption. And the attendees asked great questions.  If you haven’t watched them yet, you are missing out on a great experience!

Improving the Effectiveness of Smart Work Zone Technologies, Part 2

illinoisstudyIn our last post we discussed a brilliant new paper published in November by the Illinois Center for Transportation Studies. Today let’s look at their conclusions regarding work zone travel time systems. The writers point out that, “Two critical components for the success of a smart work zone deployment are the quality of the traffic data collected by sensor networks and the algorithms used for data processing.” We examined sensor types last time. Today we look at algorithms

They conclude that, “The travel time estimation is consistently poor for all algorithms and sensor networks investigated in this study. The main reason is that the instantaneous travel time calculation is a poor estimator of the true travel time in a dynamic traffic environment. In addition, the use of Bluetooth sensors can only provide the travel time of vehicles that just exited the work zone. Consequently, the travel time estimation even using Bluetooth sensors is not likely to improve the accuracy of the travel time estimates when the traffic conditions are quickly changing.”

This makes perfect sense. In a work zone you are more likely to see frequent and dynamic queuing. And that is the kryptonite for every algorithm superman. It’s too bad, because we would all like to see accurate travel time estimates, especially for work zones with significant impacts. But, ironically, it is those impacts that make estimation so difficult.

They also discussed the potential use of more advanced algorithms. This is a subject for which I have only a very limited understanding. So I am not able to examine the relative advantages and disadvantages of popular methods. But for work zones, they really aren’t practical anyway. Unless it is a very long term project, one lasting several years, the work required ahead of time to test and adjust the algorithms is expensive and still won’t make much of a difference in the travel time accuracy.

As an industry, we have worked for years to make our systems faster and easier to set up. This, to my mind, would be moving backwards. Instead, let’s work to make our travel time estimates more useful to travelers. Perhaps it makes more sense to talk about delay times. Drivers seem to expect predicted travel times to match their experience perfectly. But when it comes to delay times, they are more likely to be relieved when the delay they encounter is slightly less than predicted.

What the Smartphone Supply Chain Can Do for Work Zone ITS

Today we welcome a new work zone ITS blogger: JP Story of Salander. He has written a guest post that I know you will find interesting!

Smartphones are the first technology to be bought by every human being on earth. This is pretty revolutionary in the technology sector, but also has some interesting implications in the Work Zone ITS industry. I’ll give you some background and show an example of how a former fishing village in China can increase work zone safety here in the United States.


It used to be that technology was sold to a subset of the population. You’d sell mainframe computers to Universities, Fortune500 companies and governments. You’d also sell Personal Computers to families and high schools. The addressable market of a product was always just a portion of the population. That’s not the case with smartphones. Roughly 2 billion smart phones have been sold to date.

Lets take a step back though and take a look at my first computer back in 1995. A blazing fast Packard Bell, with a screaming Intel Pentium Processor (the original!).

I’m sure you remember these beige boxes adorning the desks of the 90s.

Compare that Intel Pentium processor to today, 20 years later. The iPhone6 has 625 times the transistors (the basic unit of computing) as my old beige box. On the weekend the iPhone6 launched, Apple sold 25x the PC computing power that was on earth in 1995…in one weekend.

So today, everyone gets a pocket super computer.

Yes, everyone. Sub-Saharan Africa is one of the last places on earth to be blanketed in cellular airwaves. As you can see below, they are at about 70% population coverage. 3G is lagging behind but will catch up in the next 5 years. What’s really interesting about this graph is on the right side though. Roughly 37% of the population has a cell phone and yet only 33% of the population has electricity. More people value having a cell phone and being connected to the Internet than they do having electricity. While this poses some interesting problems when you have to negotiate with your neighbors and pay them to charge your phone…it really illustrates the trend that everyone on earth wants/needs a smart phone and access to the global communications network.

The main driver of this is the proliferation of cheap android handsets. Today you can buy a smartphone for $40. Below is an example I just googled, the Maxx MSD7 AX410. In India it costs 1500 rupees, or just under $40. That’s not with any 2 year contract where they subsidize the phone over time. This is $40 straight up, and includes a touch screen, battery, cellular module, Wi-Fi chip and most importantly, the ability to communicate to anyone on earth and learn anything on the Internet. For $40. The economies of scale that allow for this kind of downward pressure on costs is hard to fathom.


To really comprehend how amazing this is, you again have to go back in time. In the 80s, 90s and early 2000s, different tech sectors were more or less ruled by single companies. Microsoft was so famously dominant in the platform sector that they had an anti-trust lawsuit filed against them by the Department of Justice. Today, Apple and Google reap all the profits and are the big shots in platforms. Likewise in the chip world, Intel used to be the big dog. Now Qualcomm and ARM are where you’ll find all the growth. In the mobile space, you used to look to Nokia for a glimpse of the future. Now you look to Shenzhen China…our former fishing village.

Shenzhen Today


Shenzhen was the first of China’s “Special Economic Zones”, where they cut a swath of land and let free market capitalism run free. 30 billion dollars of foreign investment later, and you’ve got 10 million people living and working there, the vast majority in high tech manufacturing. So instead of having single companies enjoy the economies of scale, for the first time, you have an entire city of 10 million competing to drive costs down and deliver high tech products to the entire world. Nearly everything electronic you buy – smartphones, bluray players, TVs, laptops, game consoles – was either built there, or the components that make it up were built there.


So it used to be to create a new ITS product you’d spend 5 years figuring out how to create the chips and hardware and screen and so on. Now you go to Shenzhen and say, “I’ll take a number 4 chip and a number 7 screen with a type 2 battery”. Down the block is a manufacturer who will put it together in whatever configuration you want. The smartphone has enabled us to play Legos with technology. This has given birth to a bunch of new industries in the last 5 years, such as virtual reality, wearables, internet of things such as the Nest Thermostat, drones…the list goes on. What this will also catalyze is connected vehicles, infrastructure to infrastructure, and infrastructure to vehicle communication and collaboration. This is why we’ve seen such a surge in this space – it is all thanks to the smartphone supply chain, enabling our industry to innovate and move forward.
Historically, our industry has moved slowly, but there are glimpses of this new world on the horizon. Since everyone has a smartphone, Bluetooth and WI-FI detectors have surged in popularity as a way to combat the downsides of typical spot detection from loops and provide true flow data. Processing thousands of data points on a 12V solar system? It is possible thanks to low power draw yet incredibly powerful smart phone processors. Modern microwave sensors that incorporate cell modems and cameras from the smartphone supply chain. PCMS from some manufacturers, are full blown Linux servers, enabling a host of new features and awesome features (if only they were specified in).

How else will the smart phone supply chain affect our industry? How can we assemble these “Legos of Technology” in a way that can save lives? Stay tuned to the WorkZoneITS blog, where Joe is always looking to the future and sharing his insights. Also please checkout my new blog at, where we will be posting ideas and new ways of thinking of technologies role in work zones.
This post was inspired by the work of Bennedict Evans.

All Give and No Take?

ATSSA held their midyear meetings August 12th through the 14th. The Innovation Council (formerly the ITS Council) was one of the first meetings and was very well attended. We were discussing V2I and how our systems will supply data when one of our members asked a great question. Eric Tennessen of Warning Lites of Minnesota asked, “When will vehicles talk to the work zone?” Cars, trucks and even cell phones collect a great deal of information. When and how can we begin to use that data to make our work zones safer?

He makes a great point. We are supplying information to V2I systems. Our work zone ITS sensors collect and disseminate average speeds, travel times, queue warnings and even suggest alternate routes. It is all give and no take. It is time we begin thinking about what those vehicles can tell us.

Several examples come immediately to mind. Many cars now “wake” the drivers when they exhibit behavior typical of a sleepy driver. Why can’t that data be sent to systems in work zones immediately downstream?

That could also be done for vehicles driving well in excess of the posted speed limit, or for those making frequent lane changes or following too close. Those are the drivers whose behavior will cause rear-end and side swipe collisions when others slow for work zones.

There are bound to be privacy issues. And we don’t want drivers turning these features off out of fear that their cars will report them to authorities. So such a system would have to report problem drivers approaching the work zone without actually identifying them.

There is also the problem of false alarms or, more likely, too many alarms. Any aggressive driver warning system will be beeping more often than not. But this could still be useful. When law enforcement is in place in the work zone, they could be alerted automatically. During night work when volumes are lower and drivers more likely to be impaired, workers could be warned to watch for them. I really don’t know how best to make use of that information. But I do know it can and should be used to improve work zone safety.