TTI researchers have measured traffic gridlock through an urban area lens for decades. Senior Research Scientist David Schrank explains why they’ve also been narrowing the focus in Texas, looking at specific sections of freeways and major streets, and ranking them—all 1,854 of them.
TTI researchers have measured traffic gridlock through an urban area lens for decades. Senior Research Scientist David Schrank explains why they’ve also been narrowing the focus in Texas, looking at specific sections of freeways and major streets, and ranking them—all 1,854 of them.
Welcome. This is Thinking Transportation-- conversations about how we get ourselves and the things we need from one place to another. I'm Bernie Fette with the Texas A&M Transportation Institute.
Bernie Fette:Mobility researchers at TTI have been studying traffic congestion for decades, giving a gridlock rating to hundreds of cities across the United States. In Texas, they've been taking that examination down to a detailed level, looking at specific sections of freeways and major streets and assigning a rank to every single one, all 1,854 of them. David Schrank, a senior research scientist at TTI, can tell you how the roadways on your daily commute rank on that statewide list, based on the number of hours of delay every year, along with the financial cost of that delay down to the dollar, and the amount of fuel you're wasting while you're stuck in traffic. If you're really curious, David can tell you how much of that delay can be blamed on the trucks that are delivering your groceries and your latest Amazon order. He's joined us for this episode of Thinking Transportation to help us understand why all of that detail is so important. Thanks for being here, David.
David Schrank (guest):Thanks for having me, Bernie.
Bernie Fette:So you've been doing this work for about a decade, right?
David Schrank:That's correct. We began the Texas 100 Most Congested Road Section work in, uh, 2009.
Bernie Fette:And since that time, at least it appears that from year to year, the rankings of which roadway sections are the worst-- those don't really change very much. They just seem to trade spots from year to year. So since there's so little change, why is it necessary to keep measuring all of this every year?
David Schrank:Well, transportation changes every year. We have new homes built. We have new businesses coming into town. New industries. The population in Texas is continuing to grow. And with that means transportation is changing. So with that in mind, we need to study and we need to track what is happening on our roadways so that we have a better understanding about where the pressure points are from year to year. As you mentioned, Bernie, the worst of the worst location tends to stay at the top of the list. And it's because of where those locations are in the metro regions of Texas. They're in critical locations. Like I-35 through downtown Austin, like the west loop in Houston, those are going to have traffic on them year in and year out because of where they are and the functions they serve. And so it's important for us to monitor those locations, to see how they are changing relative to other locations within those metros.
Bernie Fette:In contrast, then, it seems that we see a lot more change in the rankings for those road sections that are farther down the list.
David Schrank:That's correct. Once you get out of those top ones, you get into some of the commuting corridors that don't have enough traffic on them, 24 hours, seven days a week to make it into that top 10 or 15, but they tend to stay in the top 20 or 30.
Bernie Fette:Okay. I mentioned in the introduction how you really get into a lot of detail. You measure hours of delay, wasted fuel, impact of truck traffic. Why is that level of detail so important?
David Schrank:The detail is important because while you have two roads, for example, number one, and number two on the list, why they are there might be slightly different. For example, truck traffic on I-35 in Austin, the number-two most congested road section for the COVID 2020 year, is number one for truck traffic. And so there's different reasons for why road sections are where they're at. As I mentioned earlier, some of these are where they're at because they have congestion 24-7. And we see, for example, weekend congestion on I-35 in Austin, weekend congestion on the west loop in Houston. Whereas we don't see as much weekend congestion on some of these commute corridors. And so we need to have this detail in order to paint a clear picture about why these road sections are where they're at on the list. And then that may ultimately lead toward what we can do about trying to improve those locations.
Bernie Fette:Being able to analyze those different factors helps you whenever you're trying to come up with the solutions for those individual road sections.
David Schrank:It can lead you in that direction. Yes.
Bernie Fette:Okay. You mentioned COVID. COVID 19 caused a lot of things in life to hit the pause button-- roadway traffic included. You and your colleagues noted that not only in this Texas analysis, but also in the Urban Mobility Report, which is a nationwide analysis, several months ago. What sort of takeaways do you have from doing both of those studies in a pandemic year?
David Schrank:Well, from a research perspective is very interesting and that for the first time of study and traffic congestion, both nationwide and in Texas, we saw area-wide, statewide, national declines in traffic congestion. About half of traffic congestion disappeared during the COVID year 2020 versus 2019. That varied across the country. It varied across metro regions within Texas. A lot of it comes back to why those areas are congested in the first place. It has to do with the labor market that exists there. It has to do with the amount of trucking that's on the roads, there. Is there a port in that city that increases the amount of truck traffic on the roads. Some of these areas have more of a workforce that is on-site and essential-- warehousing, manufacturing, and those kind of jobs that you have to be on-site in order to do your job versus some that can work from home.
Bernie Fette:Yeah, right.
David Schrank:And so what we saw during the COVID year is a city like Austin that has, uh, a lot of state employees, has the University of Texas downtown as well, where you have not only government employees, but all the work- and educate-from-home that happened. We saw some reductions in some of the locations in Austin that were a little more sizable than some locations in Houston, where Houston might have a slightly larger employee population that had to be on-site. And so some of those kind of things contributed not only in Texas, but nationwide to who, which cities fared better for traffic congestion during the COVID year versus not.
Bernie Fette:Mm-hmm.
David Schrank:One of the things that we did see during the pandemic year is that truck traffic did not dissipate. Truck traffic is basically is at the same levels it was pre-pandemic. And in some locations, it was actually higher, depending on where that location was and, and how important it was in the supply chain. So what we saw is some of our Texas communities near the Mexican border, where truck traffic is trying to maintain that supply chain. We saw traffic, you know, in the port cities, across the country, also in Texas that were trying to keep the supply chain moving. And then we saw the delivery vehicles that are out in our neighborhoods now more so than ever. That truck traffic grew as well. And so truck traffic was a larger percentage of the delay that we saw in the, uh, 2020 pandemic year than in previous years. And it's probably only going to get bigger going forward as we have become more dependent now on deliveries at home and getting our groceries delivered and doing less shopping on location than we did prior to a pandemic year.
Bernie Fette:Mm-hmm.
David Schrank:So one of the main reasons why traffic congestion dropped like it did during the 2020 pandemic year in Texas, is that we had trips that weren't made. We had work from home. We had school from home. That traffic didn't happen. And so if we can eliminate some of these trips from the road system, we can have a major effect. What we saw nationally in the Urban Mobility Report for example, is that about 15 percent of the nation's traffic disappeared during the COVID year, about 50 percent of the traffic delay was eliminated. It didn't take that much traffic removal from the system in order to make a big effect. It's all about where that traffic was removed and what time it was removed. So when you bring it out of the peak periods and you bring it out, some of the most congested corridors, for example, it can have a major effect. So going forward, what we've learned from the COVID year is that any kind of remote activity can eliminate some traffic. And that can have a major effect. Work from home is probably going to continue to have a role in our transportation system. The question is how much of a role, and can it continue to keep pace with the growth that we expect in Texas and the U.S? Because for every new job that comes to a region, some of that job needs to be done from home. Otherwise we start our move toward gridlock again.
Bernie Fette:Yeah.
David Schrank:Uh, so if we have major industries in a metro region and we can do some coordination with how those industries might be able to make use of work-from-home, then we could potentially have major effects on peak period travel, but it's going to take communication and coordination. I say that because if you think about this, as we became used to our work-from-home environment during the pandemic, we got used to the fact that you could get in your car and drive anywhere almost at any time of the day. But what happens on that one day when everybody say, oh, gosh, I've gotta go into the office today. And everybody left their house at 7:30 in the morning to head in, and no one was expecting that their neighbor on each side of them is going into the office too. We would have major gridlock on that date.
Bernie Fette:Of course, you were just talking about the Urban Mobility Report, which is, again, a ranking of congestion on an urban area level, as opposed to the Texas analysis, which looks at specific roadways. I'm wondering, are there any plans to take that road segment approach to a nationwide level?
David Schrank:There are some of those sorts of analyses already happening.
Bernie Fette:Ah, okay.
David Schrank:The Federal Highway Administration is doing some work looking at, at freight on a more of a road segment basis across the nation, but only on the national highway system, which includes mainly the interstate highways, plus some of the other higher-end, more important roadways. So some of that's already happening. But one of the reasons why it may not happen in something like the Urban Mobility Report is that the solutions are going to come more from a state level or a regional level, as opposed to a top down from a federal approach. So studying things at a nationwide level to potentially try to develop solutions may not be something that is as useful as it is focusing on Texas or focusing on another state where the funding within that state is used to deal with the problems that are located and found within that state's boundaries.
Bernie Fette:And you said that you've been doing this Texas analysis for a little over a decade. Are you aware of any other states that are looking at road segment-level congestion in a way that's as detailed as they're looking at it in Texas?
David Schrank:There are many other analyses that are similar in their approach. Many of those they're looking at a spot on the road or a very small section of road, uh, between entrance/exit ramps or around an interchange, as opposed to looking at the entire road system broken into small road sections of three to five miles and sort of thing. That's one of the differences between Texas 100 analysis that we've, you know, been doing for 10 or 12 years versus some of the others that are done around the nation.
Bernie Fette:Your measurement of the traffic problem over the years has evolved quite a bit. Is that fair?
David Schrank:Oh, yes. It has evolved a lot.
Bernie Fette:Okay.
David Schrank:In, in the period of years that we've been doing congestion analyses, more so for the Urban Mobility Report than for the Texas 100 analysis, because the Texas 100 analysis has relied on GPS or probe vehicle information to supply the performance, the speed side of things versus the early years of the Urban Mobility Report, where we didn't have that kind of information. So we had to do a lot more estimation.
Bernie Fette:Has your opinion about gridlock solutions evolved as well?
David Schrank:With the availability of probe data now on the roads to give us minute-by-minute performance information, it allows us to have information at our fingertips that may lead us in a different direction than it might have 20 years ago. 20 years ago, our first thought might have been, well, we have congestion over here. Should we widen this road? Now, with this kind of information, we might see strictly from the probe vehicle speed information that maybe our problem is traffic incidents. And so we know now maybe an incident management program might get us the same bang for the buck as trying to widen a facility.
Bernie Fette:And by incident management, what you mean for the non-technical folks in the audience, that's just basically getting crashes and such cleared off the road faster.
David Schrank:That's correct. So incident management would be getting stalled vehicles, getting crashes, getting anything that, um, cuts back on the ability of the roads to carry traffic, get that removed as quickly as possible so that the traffic can get back to flowing.
Bernie Fette:In other words, having a strategy that doesn't so much look at how to change the roadway, but how to change how we use it?
David Schrank:Both how we use it and its ability to do its function, which is carry traffic. And things like stalled vehicles and debris on the roads and obviously crashes inhibits the road from being able to carry that traffic.
Bernie Fette:You were mentioning in talking about solutions where you can get some of the data you need to make those decisions. For a moment, I'm hoping we can talk more broadly about the distinction between data and information. Technology in the age of big data makes it ever more possible to examine things in ever more meticulous detail. Is there a point of diminishing returns along that path?
David Schrank:We are getting more and more information on a daily basis from the transportation system. A lot of it now is coming in because the vehicles that we have that we are purchasing have technology in them that sends information to the cloud and ultimately to the computers that we use to analyze performance. And so we now know things about whether a vehicle is accelerating, is braking, if the windshield wipers are on, if the seat belts are buckled, if the passenger seat has someone sitting in it. So we have all kinds of information coming in that we didn't have. And what that allows us to do is pile on to what we already knew. While a decade ago, we were thrilled to death to have speed information coming in from the actual vehicles on the road. Now we have information coming in that says these same vehicles were in a stop-and-go environment. They were hard braking. So we may have an issue on the road where we need to look at why they are hard braking at this one location, or that we have a lot of turning movements happening here on a highway that we weren't really expecting at high speeds. And do we need to do something about that in order to potentially alleviate a, a problem maybe before it even happens. So it is getting more and more difficult to analyze all that information or data and turn it into information because there is so much of it.
Bernie Fette:I think that's where I was going. Where, where the challenge is. Yeah.
David Schrank:The, the challenge now is to take 10 years ago, we were talking about gigabytes and now we're, we're always talking about terabytes, and I don't even know what the next byte is after that. But the thing is, it takes longer to process what we are getting now because there's more of it. But how rich it is in information continues to grow and continues to provide us a lot more detail without us having to leave our desks.
Bernie Fette:Yeah. And ultimately understanding what's going on on the ground helps operating agencies come up with solutions with not just effectiveness in mind, but cost effectiveness, making sure that you're getting the biggest bang for the buck. Right?
David Schrank:Well, there's two steps there. There's this planning level that allows us to take first pass at using this information to make a sort of first decision. Then there's the, what are we gonna do about it? What's the best solution out here? That same data may provide us that information. It also may point us toward what we really need to do is go out and use this type of device in order to fully understand what's happening there. But it saves us potentially a lot of time trying to figure out what we need to do there, because maybe we take the first step and it is the right step before we get out there to really understand what's going on.
Bernie Fette:And not just saving time, but saving money, too, it sounds like. What you're describing sounds like one of those rare cases where what you're buying now-- the data and information-- costs you less than it did a decade ago. And it's worth more than it was a decade ago.
David Schrank:We're still kind of learning and feeling our way through this new big data world.
Bernie Fette:Okay.
David Schrank:It, you spend more time to analyze this data. Uh, you used to spend send people out into the field and collect data and put devices out there to bring data back to you and have to maintain those devices in order to bring your data in. Now you're buying the data, but you're spending more time analyzing that data to get you the information you need. So I don't, I'm not sure yet about true cost effectiveness, but one of the things we are seeing is that it is a whole lot less risky to have this data purchased than to have people out on the side of the roads trying to collect gigabytes, terabytes of data that come in daily, monthly, yearly.
Bernie Fette:There's a connection between traffic congestion and the economy, right? Stronger economy, more traffic.
David Schrank:That's been the general concept we've looked at over 30 years in the Urban Mobility Report. And, uh, it still seems to hold true.
Bernie Fette:Some people might believe then that a certain amount of roadway gridlock is just a price we pay for prosperity. What's your thinking on that?
David Schrank:One of the reasons we have traffic congestion is that we have an always changing transportation need and that changing transportation need comes from economic activity. Economic activity does not exist in a vacuum. We have new houses being built in areas. We have new jobs coming into areas. We have different needs that are happening, and that changes the traffic patterns in a region and changes the needs for transportation in a region. And so one of the problems that comes with growth is a lot of times that growth in population and job market and other things can happen faster than we can put a transportation system in place to try to deal with it. And so we are off and chasing that growth in trying to do something about it, as opposed to being out in front. Because of that, we oftentimes are looking backwards to what our biggest problem is rather than looking forward to what might be our biggest problem, 2, 3, 5 years from now.
Bernie Fette:And you can only forecast so much.
David Schrank:That's correct. I mean, a lot of our transportation models in this industry look out 20, 30 years. It would be very interesting to look back and say, how did we do? But a lot of times we, we don't have the time and resources to do that. So we just keep looking forward and looking forward to what we think is going to happen, uh, and try to stay ahead of it. We have places in the country that are growing. Population in Texas is supposed to, you know, basically double in the coming 20, 30 years. And with that, we know we're going to have a demand for transportation that exceeds what we have right now. And so all we can do is keep looking forward and trying to put money where it's going to give us the biggest bang for the buck in our transportation system. And a lot of times that's trying to fix some of these choke points that we know exist in today's world, because they're only gonna get worse if we don't do anything about them and, and demand on the system goes up, you know, 10, 20, 50 percent.
Bernie Fette:Yeah. And you mentioned that, you know, the 20- and 30-year models for planning, but I don't know that any one of those models had a pandemic factored into it.
David Schrank:And I think from that perspective, one of the thoughts here is, you know, kind of, we, we may have had a reset here for a year or two, meaning that we had our traffic congestion drop back to what we saw a decade ago or more, maybe even 20 years ago. But we also saw how quickly it started coming back.
Bernie Fette:Yeah.
David Schrank:And we were back to pre-2019 levels by the end of the year, I believe the start of the 2021 year. And so a lot of people were like, well, it's, it's coming right back. What we don't know is who was out there in that traffic? Is it different than what we saw before the pandemic? And as we recover from the pandemic and what does that mean for the future? Is telecommuting going to play a bigger role? It might. But 25 to, you know, 100 percent population growth is going to offset potentially what we might get from the work-from-home benefit.
Bernie Fette:Mm-hmm. Last thing, 50 words or less. You've been doing this for a while. What drives you to keep showing up every day?
David Schrank:The interesting thing in this job is how it is evolving. 30 years ago, we were estimating things. 20 years ago, we were starting to get some data come in, as we started getting a little more technology, especially on roadside devices that could collect data. Now we're getting data coming straight from the vehicles. And it's interesting to see the evolution every day of the new questions we can answer, the new information we can put out there every day from the data coming in. And that keeps you coming back to the job and keeps you wanting to make sure that we are doing as good of a job as we can with this great data that's coming in to inform decision makers and policy makers, and also the motoring public about how their transportation system is performing.
Bernie Fette:Way over 50 words, but still pretty good.
David Schrank:< laugh>.
Bernie Fette:David Schrank, senior research scientist at TTI. Thank you, David. This has been really great. Thank you for sharing your time with us.
David Schrank:I appreciate it, Bernie. Anytime.
Bernie Fette:As uncomplicated as roadway congestion might appear on the surface, it's anything but simple. Understanding why traffic jams happen is just as important as knowing where they happen. And those reasons can include anything from new schools and businesses to employment patterns and population growth. And-- here's the tricky part-- how those reasons can change from one year to the next. Research, like that funded by the Texas Department of Transportation, aims to unwrap some of the complexity behind gridlock and lead to the best approaches for what might help to fix it. Thanks for listening. We hope you'll be back next time for a conversation with Jeff Borowiec, an expert in urban air mobility, which envisions safe and efficient movement of people and cargo at low altitudes within urban and suburban areas. In other words, flying cars. Thinking Transportation is a production of the Texas A&M Transportation Institute, a member of the Texas A&M University System. The show is edited and produced by Chris Pourteau. I'm your writer and host, Bernie Fette. Thanks again for listening. We'll see you next time.