The Math Doesn't Lie: Roundabouts Make Driving Safer, More Reliable, and Less Technology Dependent

Roundabouts and other innovative intersections offer a number of advantages over more traditional designs, including improved sustainability, reliability, and resilience--and astonishing benefits to traffic safety for drivers. Amanda Austin, the Texas Department of Transportation's (TxDOT's) lead in implementing these alternative designs, and TTI Research Engineer Marcus Brewer join us this episode to discuss them. For more information on TxDOT's work in this area, see the department's Innovative Intersections web page.

Transcript

Allan Rutter: 0:14

Howdy everyone. Welcome to Thinking Transportation--conversations about how we get ourselves and the stuff we need from one place to another. I'm Allan Rutter with the Texas A&M Transportation Institute. When I was growing up, the word "roundabout" was used in my family as a synonym for meandering, either in a story or on a journey. By the time I became a teenager in the early Seventies, roundabout was the title of a Prog Rock tune with Rick Wakeman keyboards. Today, we'll define and discuss how "roundabout" refers to a type of innovative intersection designed to eliminate conflict points among drivers and reduce crash frequency and severity . Joining us today are Amanda Austin, transportation engineer and roundabout and alternative intersection design (or RAID)--we're gonna hear about that today--lead in the Texas Department of Transportation's Design Division; and Marcus Brewer, research engineer with the Roadway Design Program in TTI's Transportation Operations and Roadway Safety Division. Both Amanda and Marcus are licensed professional engineers in Texas. Welcome to you both.

Marcus Brewer: 1:28

Glad to be here.

Amanda Austin: 1:29

Glad to be here. Thank you so much.

Allan Rutter: 1:31

So as an older person and longtime Texas resident, I can remember traffic circles of various sizes in Texas cities like the one in Waco on US 77, just east I -35 with a hell camp burger place on it, and a big circle on US 84 on the southside of Lubbock. Now, I've also been in taxis in Boston, which seems to have almost as many rotaries as Dunkin Donuts locations. Can you either of you tell me about what are the differences between a traffic circle, a rotary, or a roundabout? What is that all about?

Amanda Austin: 2:06

Very good question, Allan. I'd love to answer this one because I actually grew up on the East Coast, and I've driven through some of those rotaries in Boston and a few in my home state of Maine. So a good way to remember is that circular intersections have a lot of different names. A modern roundabout is a circular intersection as are traffic circles and rotaries, but they're definitely not the same thing. Now of those, the modern roundabout has the tightest definition, I would say, compared to traffic circles and rotaries. A rotary is, generally speaking, a larger intersection, a larger circle, higher speeds, a little bit more of a free-for-all. A couple that I drove through for my driver's test, for instance, had a rule where it was just, there was an inside lane and outside lane, and you weaved between them as you navigated the circular intersection. There's one in Portsmouth, New Hampshire, that is very large. You could drive around the circle at 40 plus miles an hour, and that's typically a rotary. Now, a traffic circle is most often applied to, like, a small neighborhood traffic calming type of a circle. It might just be a small circle of concrete in the middle of a neighborhood intersection. But I've also heard "traffic circle" used for some larger circles like rotaries as well. Sometimes traffic circles might have a signal incorporated on it. You may have to stop in the middle of the circle, whereas the modern roundabout has three distinct characteristics. The first is obviously that it's circular and that you circulate counterclockwise--'cause we're in the U. S., It's opposite in the UK--because the second is that you yield on entry and that's one of the most critical ones. Like I said, some traffic circles you might enter when a signal tells you to into the circle, and then you stop to let other people enter. In a modern roundabout, you always yield on entry to the circulating vehicles. Once you're in the circle, you have the right-of-way to exit at your appropriate exit. The third aspect of a modern roundabout is slow speeds. And that's the biggest difference with these rotaries, is that you have speeds under 30 miles an hour or for single -lane or smaller roundabouts, possibly even under 25 miles an hour. You cannot drive around a modern roundabout at 40 plus miles an hour. They're just not designed that way. And because of that, why we call it modern roundabout is because while traffic circles and rotaries like the ones you mentioned, especially that one in Lubbock, they're older--they're decades and decades ago--we've learned that these circular intersections operate best with these three components. And so modern roundabouts are basically started in the late Nineties in the U.S., the early Two Thousands, the last 20 to 30 years. And that's what TxDOT , Texas Department of Transportation, is proposing. And we're moving more to install these modern roundabouts with those characteristics.

Allan Rutter: 4:46

So that's very, very helpful , particularly for a non-engineer like me. Now, before we talk about some of those alternative intersections, Marcus, can you tell our listeners about some of the things that can go wrong at a traditional intersection, sort of right angle of two roads? Why would we want to think about alternatives?

Marcus Brewer: 5:05

Sure, that's a great question. There's a few key things. When you have just your traditional four-leg intersection--you mentioned right angle--it's very important. We put up all kinds of traffic control devices, whether it's stop signs or traffic signals, red, yellow, green, all kinds of things we can do. But ultimately people still have to obey those. They have to abide by those. And you have instances where people don't for various reasons. And so what that does is that allows what we call angle crashes or right -angle crashes. A lot of people refer to 'em as T-bone crashes where you have one car run into the side of another. And those tend to be very serious, not only in terms of damage to the vehicles, but also in injuries and maybe even fatalities. And not only the angle, but also the speed because you have straight lines on all four of those approaches and no physical restriction on people's speed as they approach, their approach speed. And you put those things together, you have the potential for having some serious crashes if people did not obey the traffic control devices that are there. And so those things are not really possible at a modern roundabout because you eliminate that opportunity for the right angle. It's just designed such that you really can't have that. And then the speeds are lower again; by design, people enter and travel through and exit a modern roundabout at lower speeds. And so any crashes that do occur are going to be at smaller angles. Instead of the 90 degrees, you may have more like 15 or 20 or 25 degrees. And so they're more sideswipe , more gentle, and at lower speed, which means damage to vehicles is less and the chance for injury is greatly reduced. The chance for fatality is almost eliminated; not quite, but almost. It's much more difficult to have a fatality at those . Another key point is that roundabouts reduce what we call conflict points within an intersection. There's places where vehicles traveling in different directions meet or come together and merge or they diverge or they cross paths, and there's much fewer of those conflict points at a roundabout than there are at a traditional intersection. And so all of those three things combine to improve a lot of safety aspect and performance. And we've seen that in roundabouts that have been built in Texas and across the United States where crashes are reduced, injuries are reduced by--reduced roughly two thirds, fatalities are reduced by over 90%. And so the track record is borne out in the results as far as crashes are concerned about the safety performance between roundabouts and traditional intersections.

Allan Rutter: 7:43

Now, this may be a good time to follow up on that, Marcus . Amanda, I know that your program has, in talking with other people within TxDOT , you have some stats on TDOT's experience with some of these alternative intersections.

Amanda Austin: 7:59

Yes . So TxDOT has been doing alternative intersections in different areas across the state. Now I'm gonna touch on something Marcus said with the conflict points. Modern roundabouts do have the fewest conflict points, the slowest speeds out of all of our intersection types, generally speaking. But there are also other types of intersections that reduce the number of conflict points, and so improve safety. When you reduce the number of opportunities for vehicles to cross one another's path, you're going to just get less crashes. So some of the other ones that TxDOT has been doing and is continuing to look into, they all of course have acronyms. There's R -cuts and DDIs and DLTs and MUTs, and all of that. But I'll spell out a few of them. R -cut stands for "restricted crossing U-turn." And what that means is, you generally take a four-way or a T-intersection and the minor road that comes into the major road is restricted to basically right in, right out. When you're on the minor road and you're trying to exit, you can only go right. And so you might ask yourself, well, how am I supposed to go through or left? You turn right and then they're down the way a bit. There's a designated U-turn location. It sounds very simple, and I know sometimes people don't feel comfortable making U-turns, but our cuts are pretty much second to roundabouts in reducing fatalities and serious injury crashes. Our cuts have been shown to reduce fatalities up to 70%; fatal and serious injury crashes by up to 40%. So they're a really great option. And the reason for that is you're separating these key decision points when you only have to turn right; that's all you can do. And then you do a U-turn and you do them separately. So you know when you're trying to cross traffic, right? We're taught in driver's ed --left, right, left. You know, instead of having to do that and trying to gauge the oncoming vehicles from one direction; in the other, you're just making one decision at a time. R -cuts help in that way. Median U-turns (or MUTs) are very similar. You're only allowed to turn right in, right out. So again, you do a later down U-turn. So MUTs and R-cuts are very similar. DDIs are diverging diamonds, which is a very interesting one. And boy, that's a little bit harder to describe without pictures, but you're basically ... they're used at freeway interchanges. And Marcus, if you wanna chime in on a better way, I don't think I've ever had to describe DDIs before without a visual aid, but basically when you're coming off of, like, a freeway ramp, you can turn left or right and you cross the vehicle paths across the bridge, and so they're on opposite sides and it basically makes left turns easier.

Marcus Brewer: 10:32

Yep . A lot of times I think of a DDI by a separate name that sometimes people give it, which is "double crossover." And so essentially, if you're a driver going through the interchange, you cross directions of traffic twice and you are driving on the left side of the road for a very short period of time. But what that does is, it allows the left turns to get onto the ramp much easier. You're down to two signals and the signal operation is much simpler. There's only two phases in each direction. You don't have left turns and throughs and rights and all the things that take up a lot of time, but you also then reduce the opportunity for some crashes as well. And so you drive on the left side for a little bit. But if you're continuing through, then you cross back over to the right side and you keep going. And when designed properly and signed and everything as it should be, it's very smooth and you can go through without really knowing that you did it till you're through. And what ends up happening is that you can put a lot more vehicles through a DDI in a shorter period of time than you can with a lot of traditional intersection designs as well.

Amanda Austin: 11:31

And I will say to the common driver, even transportation engineers, if you're driving through one, you likely won't even notice it until you're through it. I have driven through one--this is my job--and I drove through one in Florida without realizing it. And it was after I got through that--you know, my husband was driving--I was like, "we just went through a diverging diamond!" <Laugh> , you know, "what just happened?" It was so cool. I was very excited. But again, it's something that you won't notice until you get through, but it moves traffic much more smoothly. It reduces conflict points, and so it increases safety.

Marcus Brewer: 12:02

And we've seen that here in College Station, even with the DDI that's on FM 60, over 2818 near the airport; we were having crash problems there: T-bone crashes. People coming in, you know , it's on the edge of town, high-speed approach from the west ... and those crashes have been eliminated. You can't do those anymore. And the traffic backups that used to occur don't anymore as well. And it's been a success. So even locally here in the College Station area, we've seen some improvements using these types of alternative intersections.

Amanda Austin: 12:32

So those are just a few of the ones that we're working on on the ground, and we're looking to put in even more of them wherever we can.

Allan Rutter: 12:40

So maybe one way of thinking about this distinction between a restricted U-turn and a median U-turn is maybe the scale of the U-turn. The median may be a little wider in terms of how much space you've got, but one of the things that kind of means is that some are more experienced within Texas on these things being distributed around the state. Marcus, what's been the experience or history in other states? And Amanda , feel free to chime in on considering and implementing these kinds of alternative intersections. Where else have people been doing this and what's been their experience?

Marcus Brewer: 13:16

That's a great question, Allan. As with a lot of things, different states do different programs and initiatives at different times and different speeds. Definitely North Carolina has been at the forefront, I would say, of implementing these types of innovative or alternative intersections. And they've done so with great success. They have done quite a number of, not only roundabouts, but definitely getting into the DDIs, into the R-cuts or the median U-turns. Another state is Michigan; and if you ask them, MUT might stand for "Michigan U-turn" instead of median U-turn, because they were kind of at the forefront of that even before a lot of the alternative intersection type of movement really started to take hold with some of these other designs. And they've been using 'em for a long time and doing it well. Kansas is another state I'm familiar with--not as high population as the other two that I mentioned--but they have been more proactive at building in particular roundabouts on their state highway system, not just around urbanized areas and population centers, even on their rural intersections, to try to accommodate some of these. And that's one thing, I think, to keep in mind is that all of these intersections we're talking about have as one of their focuses, the intent to better accommodate left turns, both in terms of safety and in terms of operations. Because those left turns take more time, they involve more potential conflicts, lots of things go into that. And if we can make that easier on everybody, then the system works better and people can get from place to place more efficiently and more safely. And so some of these other states have kind of taken the lead on that and developed some guidance that they've followed, and other states then kind of follow suit after we see the track record and they continue to improve the system in Texas and elsewhere as a result.

Allan Rutter: 15:00

So Amanda, as you guys have been standing up this RAID--roundabout and alternative intersection design, RAID --as you guys have been doing this, what are some of the other ways you've been describing or advocating for the consideration of these with your colleagues within TxDOT? What's the sales pitch for the ... here's why, even though this isn't a traditional thing in terms of multiple years, here's why you should think about this.

Amanda Austin: 15:29

Very good question, and I have several different sales pitches of various links. Naturally, I will say briefly, just to tie back to what Marcus said about other states, RAID--the acronym actually comes from Georgia; DOT Georgia sent the head of their RAID department to us in Texas. We requested that they would come, and they came and gave a presentation at a roundabout summit that we held a couple years ago in May with representatives from most of our districts. And they gave an excellent presentation on how they started doing roundabouts. So I always like to give a shout-out to Georgia DOT, because that presentation had a really big impact on our program, and we decided to name it RAID after that. Although I will say that, from a PR standpoint, RAID is often seen more as a bug spray. So we ended up naming our program the Innovative Intersections Program. And so we have a TxDOT.gov website for innovative intersections. So that's a little bit more information on the RAID acronym. But as for a sales pitch, the short and sweet one is knowing the stats for these alternative intersections and roundabouts in particular. You know, Marcus mentioned 'em earlier, but I just, I always like to restate them because they're so powerful. Roundabouts reduce fatalities by 90%, nine outta 10. We don't have anything short of a fully grade separated interchange where there are no conflict points. We don't have anything else in our toolbox with that safety record. It's just, it's astonishing. We work in small percentages most of the time. We try to make our lane widths correct, we try to do good shoulder widths, you know, approve a little here, a little there. But a roundabout in one fell swoop pretty much eliminates fatalities. And the few fatalities that do happen are usually single vehicle under the influence at night. It's very, very rare that there's a multi-vehicle incident with a fatality at a roundabout. And so the shortest pitch I have is if we're serious about eliminating roadway fatalities, you know, in Texas, that's our Vision Zero. Some states call it Road to Zero, but we all agree that zero fatalities is what we should be shooting for--no fatalities acceptable on our roadways. And so if we're serious about Vision Zero, we're serious about ending roadway fatalities, we've got to get serious about roundabouts. A third of our fatalities on our roadway are due to intersections, and they're primarily because of those troublesome left turns that Marcus talked about. That's where the severe T-bone collisions come in. And so if we know that a third of our fatalities are intersections and roundabouts reduce fatalities by 90% or R-cuts by 70%, we really need to be looking at these at every one of our intersections, every single one. We've gotta take a look at those. The way that we do that now is within our project development process. You know, when we have corridors that we're improving or we have troublesome intersections, we just established an intersection evaluation process where we are asking anytime that we reconstruct an intersection, we're gonna look at all of our options. That's something that TxDOT is doing now that's pretty new for us. We stood that up in June, so about six months ago . And districts are learning how to do that. So that's what my RAID team does, is we support our districts with resources, with training, with, you know, subject matter experts to look at all these different types of intersections, figure out what's gonna work best, where, and then implement them. Sometimes our districts need help with public involvement. A lot of times these intersections are completely foreign to people, you know. A diverging diamond, they may never have seen one, or they might have some preconceived notions about roundabouts, especially if they've driven through one of these traffic circles we were talking about. And so we provide support to help educate stakeholders, educate the public on just how powerful these are. To go back to my elevator speech or why I advocate for these, the safety stats are really, really powerful. But there's a lot more that roundabouts can do as well. One of the simplest ones that people often don't think about is that they're one of the most resilient intersections that we have. Resilience is a very big deal here in Texas with all of the natural disasters that we get of all varieties. But typically any natural disaster is gonna knock out the power. When the power goes out, our signals stop working, and when the signals stop working, traffic backs up. But roundabouts don't have signals, so they just, they keep working. Florida in particular, they're installing a lot of roundabouts, they're promoting it from the DOT level down to the local level. And it's primarily because of the resilience of them and the operations improvements as well. Because roundabouts, you yield on entry, you don't have to stop. If there's an opening, you go, so the next time you're sitting at a red light for two, three minutes or you know you're approaching the light turns yellow and you stop and you know you've got the full cycle to wait through and, you know, you're looking at the intersection and, say, all the other legs have flushed out, nobody's going through the intersection, you're just waiting for your light to turn green. Just think to yourself, if that was a roundabout, I could have driven through it by now. So there's a lot of different benefits to roundabouts. They can be designed to accommodate bikes and peds really well. They can be designed to accommodate trucks. They're very flexible, they're very site specific. So if you couldn't tell, I'm very passionate about it, I get very excited about them. I just think they're the bee's knees.

Allan Rutter: 20:29

After hearing you talk about that, Amanda, it's like I want to go out and spread the roundabout gossip <laugh>. But you mentioned trucks, so let's talk about that a little bit. One of the things we've been helping TxDOT's district out in Odessa deal with increased truck traffic, particularly the fact that you have almost urban levels of traffic and entries and exits, lots of curb cuts to go to industrial sites, but they're on roadways that are designed for rural purposes, and that has some real issues with it. And so as we thought about, hey, you know, maybe this would be a good opportunity, particularly for some T-bone intersections, where one road ends into another roundabouts might reduce some of those conflict points. And particularly for trucks which have acceleration problems, maybe there might be some alternatives there. What are some of the things that roadway designers need to consider to build a roundabout so that it accommodates trucks, even larger trucks, oversized and overweight ? I'll start with you Marcus, but I know Amanda has some things you can contribute to that too.

Marcus Brewer: 21:34

Sure, thanks. Yeah, there are some key things to consider because it is a bit of a balancing act because that's one of the things as we talked about already that makes roundabouts work so well, is the lower speed. And to do that you typically have a smaller footprint, your circle is smaller, your circulating roadway is smaller to help encourage that. But when you're working with trucks, when you're specifically focusing on getting trucks through an intersection and or when it is in a rural area, that tends to be higher speed, there's a different balance to manage the needs of the users there. And so in many cases that circle is made a bit larger, the speed is a little bit higher, but still not great, what I call a really high speed, probably in the 35 mile per hour range, maybe 40 , which is still quite a slowdown from your typical rural highway, but not bad. But you also then tend to make wider lanes for those trucks, particularly if it's oversized/overweight on the approach and within the circulating roadway. But also in order to not overcorrect and not provide a wide open environment, if you will for passenger vehicles, you don't widen the lane completely. But what you can do is add something called a truck apron in the middle to where there's still a bit of a curb there. But a truck traveling at those lower speeds and the larger vehicle can mount that curb, can get up on that curb and use that extra space to travel around the circle and still provide kind of a wider footprint or a bigger turning path for those larger vehicles to make it through. And that can be accomplished. And we've seen it--again, North Carolina--we've seen it in Kansas. Kansas has a roundabout that's specifically designed for that near a large distribution center where trucks, 18-wheelers are the primary design vehicle, if you will. It's very heavy on trucks. And similar to what you mentioned Allan, out in the Odessa District and some of the energy exploration where those larger vehicles make up a very high proportion of the traffic stream. There's also some other things that can be done if you know that you have a heavy right-turn movement. For example, you can make a bypass lane that goes around the intersection completely for right turns only that takes those vehicles out of the circle and can improve that. And that can still be done on appropriate speed. It's not a high-speed right-turn lane, but it, it helps to facilitate that travel around. And so there's a few other things that can be done. I've even seen examples of roundabouts that are on routes that are commonly used for oversize/overweight. You can put extra things in the center, you know, maybe you have barricades that you can temporarily remove and they can drive straight through because you've shut down that intersection basically for that oversized vehicle to use. And so there aren't any conflicting vehicles at that moment when it goes through, and you can make some adjustments. So there are a fair number of tools in the toolbox for the designer to use, but those things do have to be considered early on in the design process so that the needs of the intended users can be included in the design that's ultimately put on the ground.

Amanda Austin: 24:42

Very good points, Marcus . And something you touched on: good design has to balance the needs of multiple different users, right? So you know, a good roundabout, it's a very, very delicate and fine line between right-sizing it, making it small enough to reduce those speeds, like you said, but large enough to accommodate trucks. And so one of the ones that I had the privilege of working on was up in Washington State. They had a truck route, they were building a new route, new road. We don't see brand new roads very often anymore, but it was a brand new route to bypass a small little town that was completely inundated by a local rock quarry. The name of the town was called Granite Falls, so that gives you a sense of what that was there. But they had these, we call them dum-and-pups, which is the dump truck with a big trailer way out behind it. And they would have those going through their little town about three every minutes. So the state and the county got together, decided to build an alternate route, and they decided they wanted to put three roundabouts on that route. And the very first one that you come to when you're, you know, headed towards the quarry is a T -intersection. It's a single-lane roundabout and it's not that big. We actually measured the circulating speeds after it was installed and they were about 20 to 22 miles an hour. So it's actually pretty slow. But it was designed to accommodate these dump-and-pups. But we also had to accommodate oversize/overweight. There was a 112-foot-long lowboy truck that had to be accommodated. And when we ran it through the design we made sure, again, those truck aprons that Marcus mentioned were appropriately sized. We had truck aprons both on the outside of the roundabout and the inside of the roundabout and we did a test run. And when the low boy came through the road hadn't been finished yet, so he had to pull a U-turn. And so this 112-foot-long permit-only load truck pulled a U-turn through this roundabout--besides it's about 150 feet in diameter--and it made it without driving over any of the curbs. Didn't end up in the center island, it didn't drive off the road, it made it. And so I often hear like, "oh, you know, roundabouts can't accommodate trucks, there's no way, you know, it's this tight little circle." It's like, well how many other intersections that you know of can accommodate a U-turn by 112-foot-long truck? So when designed well, they can. And one other thing I wanted to touch on is the truck aprons. Like you mentioned, a lot of drivers, we don't really use truck aprons very much else in our roadway designs. They're pretty rare. And so oftentimes drivers, even truck drivers we find are not familiar with what these are. So if you're ever driving through a roundabout and you see a raised concrete area, but it's maybe only raised a few inches, it's a different color. It's got like a stamped concrete that is a truck apron . So if you see a truck driving over it, they're supposed to, it's designed for that. It's usually a thicker concrete, reinforced concrete. And so that touches on one area that I think is really important to accommodating trucks is, design is the first step. But the second is, you gotta do good outreach. That's something we're working on as a program is outreaching to the freight industry as a whole and making sure they understand what these features are. But also, you know, I see outreach as, it's often a two-way street. I've had some conversations with the Texas Trucking Association and when I go out and talk with them, I always want to hear back what their concerns are. You know, in talking with the specialized carriers and rigging association, we had a really good conversation with them. They kind of laughed because a low boy for them is, like, entry level . They only go up from there, you know, they're the ones hauling the wind turbines and the really, really big loads. And that's where you get into like what Marcus talked about. You know, you might have to provide a way for them to just drive straight through the roundabout, but when those loads come through, they're pretty much shutting down the road anyways. But having those conversations and making sure we understand what their trucks are, so we're always improving our designs, but then also helping to educate their drivers on, you know, the truck aprons, the best way to navigate roundabouts, especially if you have a multi-lane roundabout. I think that's a really important aspect as well to make sure that they can get through there as best as they can.

Allan Rutter: 28:23

Amanda, I can testify to your advocacy and your outreach. I first heard you talk about the program at the Texas Freight Advisory Committee meeting earlier this year where you were doing that targeted outreach. "Let's talk to freight folks about what this looks like, how to make sure that you're accommodating their interest." And that's where I learned how effective Amanda is as a communicator. And two , here's the really great example of doing some outreach. Now, one of the things you guys have talked about is what a roundabout does to decrease speed. I've gotta admit that I've had to help my bride of more than 40 years become a roundabout fan. We live north of Frisco. And I think Frisco, Texas, has more roundabouts than almost any other city in the country. And I think I've got her to understand that the speed differential is one of the design purposes. But one of the things that our neighbors, they tend to approach some of these roundabouts as Formula-1 road features, not necessarily something to be slowing down for. So talk a little bit about how signage, both advisory speeds and how to tell people what to do once they see the lanes, how to communicate to drivers to come into a roundabout and use it to make the most of its design purpose.

Marcus Brewer: 29:41

I think it's important to stress to drivers who may not be familiar with roundabouts that, while everyone does indeed have to slow down when you approach a roundabout, not necessarily everybody has to stop. Amanda mentioned it earlier about having to stop for a red signal when nobody's there. The slowing down is necessary, but not having to stop, you can keep going through. And it really does help in the efficiency. And while it may seem counterintuitive, the slowing down part, just like not being able to drive in a straight line, if you're going straight through, the fact is it really does work better. And the more you drive through them, the more familiar you become with it and you understand it, at least on some level, even if maybe it's difficult to put into words, the familiarity definitely helps. But if you're talking about rolling out a roundabout on a new location or you know, a new group of drivers that may not be familiar with them , it's really important to stress that. Yes, there are some different things you need to know. The yielding is important. We see a lot of times people as it turns out, don't necessarily encounter a lot of yield signs elsewhere other than on freeway ramps. And so they may not be as familiar with that as we think they are, but it's there for a purpose and it really does work. And then again, the safety benefits are just tremendous. And so understanding, you know, you pull up, you yield, you look left, if no one's there, you can keep going. You don't have to wait for a signal. And then you pick where you want to exit the roundabout and you keep going. And it really does work phenomenally well. It does require the driver to maybe pay a little more attention rather than "is the light red or green?" But in the long run, it really does work not only for the individual driver, but for the system as well.

Amanda Austin: 31:19

And I try to reassure drivers too, it can be overwhelming if you're not familiar with roundabouts just because it's new. But, say, you're at the local grocery store and when you pull outta the grocery store, you have to make a left. You've gotta do that complicated head movement, right? You're looking in both directions. You know, cars are going pretty high speed. That's actually a more difficult maneuver than driving through a roundabout because when you pull up to a roundabout, you only look left, you don't have to look right. Cars are only coming at you from one direction, and they're going relatively slow. So like Marcus said, you look left when there's an opening, you go and then you proceed to your exit. It really is that simple. It does get a little bit more complicated at multilane roundabouts. The key to that, I tell drivers, is pick your lane ahead of time. According to the signage, there should always be destination signs , giving you a clue as to which lane to be in. A general rule of thumb is that it's really not that much different from a traditional signalized intersection. If you wanna turn right, you know, forget there's a circle in front of you. If the road you're going to is to your right, you should probably be in the right lane. If the road you wanna end up at is to your left, you probably need to be in the left lane. If you're going straight through, you're proceeding, you know, on the same road, you can probably get in either lane. A general rule of thumb--there are some exceptions--there are some roundabouts with two left turn-lanes. So you could technically turn left from the right lane, but those are rare. But look at the signage, proceed slowly. If the signs are coming up to you, slow down, you know, digest the sign, get in the correct lane, and then follow that lane through the roundabout. Good roundabout design, you should never have to change lanes in the roundabout. Now, those old school rotaries and traffic circles, you might, but the modern roundabouts we're putting in, you choose your lane ahead of time, you follow it all the way through. The other thing I tell people is don't panic if you get to the yield line and you need a second to decide if you have an opening. You know, don't honk at the person in front of you if you're used to roundabouts and they're moving too slow. I've seen people do some crazy mistakes in roundabouts. I've seen people drive the wrong way, turn left into a roundabout and drive the wrong way around . And of all those videos I've seen, I haven't seen a collision because everybody's going so slow, they can stop. They can accommodate the person who doesn't know what they're doing. So just, you know, take a deep breath, let people figure it out, you'll figure it out, and you'll get through it. It might make you nervous, but it's gonna be okay. <laugh>

Allan Rutter: 33:31

It's both reassuring and it kind of speaks to maybe the final question, what's likely to happen, at least in Texas, in the future? What are the prospects for these innovative intersections, Amanda, are we gonna see more of them? What's been the experience that you've had with your colleagues within the districts around the state? And for our listeners, Texas has 25 districts, we're a big-ass state, so there's lots of us. What's been your experience in how people have responded, and what's likely to happen in terms of are we gonna see more of this?

Amanda Austin: 34:05

That's a great question. You know, when we started this program, we didn't really know what the response would be , but I've been really pleasantly surprised. I would say that there are a lot of people out there within TxDOT, within our local agency partners, cities, and counties that have wanted to do or have been trying to do roundabouts, alternative intersections for years and are just really excited that TDOT is on board and supporting these. And so I've had people come outta the woodwork, to be honest, asking for our support, asking for help, just really excited to get these off the ground. So I think they're here to stay and I think we're gonna see a lot more of them. Now. I will say, when it comes to the pace of change, a lot of people don't realize that roadway projects take many, many years. If you think of a roundabout today, it could be 5 to 10 years before you see it on the ground. Oftentimes within our project development process, particularly at TxDOT, roadway projects--you might spend a couple years planning it. You spend a couple more years designing it, possibly purchasing right-of-way if you need a little additional space. So you're looking at anywhere from two to five years in the planning and design stage, then you gotta find funding for it. So, you know, we're often looking at projects four or five years down the road. I think the pace is going to pick up, it's going to accelerate, but it could be a few more years before we really see the fruit of this program on the ground. So I'm still very excited. Pretty much every district I've talked to, every part of the state, I'm excited to see several projects, both in our Pharr District, in our Lubbock District moving forward, roundabouts and R -cuts. They're excited to have tools in their toolbox to reduce fatalities. And so I think that while we have a long ways to go, I think we are already making good progress and excited to see how much further they can go. I will say we started a database, you can access it through our TxDOT .gov innovative intersections website. We started counting... we have over 900 of these innovative intersections across the state of Texas right now, and over 650 of them are modern roundabouts. So you know, we've been doing these for a while , but now we have a big push to really make sure we consider them everywhere, on every intersection we reconstruct. So I hope to keep building that database as quickly as we can.

Allan Rutter: 36:12

Well, that is really cool to know. And it's also great to know, a part of having a program is, you measure what you're already doing. That's an important thing. Now both of you guys are clearly motivated to make a positive difference in traffic safety. Tell me, tell our listeners maybe, what are some of the reasons you're eager to show up for work every day?

Amanda Austin: 36:31

I'll say, I think this has been my most favorite job I've ever had. I'm obviously very excited about roundabouts, but more so I'm very excited to be able to make a difference in my world of transportation engineering. I'm very inspired by the Road to Zero or Vision Zero, or eliminating roadway fatalities. Every time I hear about a crash on the news, I immediately think, what can we do different? And so I am inspired and motivated and convicted really from an engineer's perspective to do everything in my power to save lives on our roadways. So I'm motivated every day to build this program, to improve our intersections. And honestly, I'm very grateful to the leadership that we have at TxDOT that supports these efforts, and they've given me space and flexibility and resources to pursue these tools that really reduce fatalities. And so I am excited because I have these opportunities, and we're always trying to think of new ideas, new innovations, and the way that we do our design to save lives. And I've never had another job quite like it, and it's pretty exciting.

Marcus Brewer: 37:33

I would echo some of those points in that it's great to be able to apply things that we know into making people's lives better, in this case on the roadway, so that they can get from place to place more safely. They can do so more efficiently, spend less time getting from place to place and actually more time doing what they wanna do. And roundabouts are a great example of that. And other intersection types as well to be able to apply things that we've learned not only about roadway design and operations, but about what we've learned on how people drive and how vehicles can perform and really help people. And that's what I really enjoy being able to do, is helping to improve those things. And roundabouts are one more tool in the toolbox that lets us do that. And you know, a lot of the things that maybe the average driver drives through on a given day, they're not gonna notice all of the efforts that the research went into to put that on the ground. But that also kinda means we're doing our job, 'cause that means it works and people are able to just go about their business. And if we're doing that, then we are in fact helping not only people of the state of Texas, but drivers in general as a profession. And it's really exciting to be able to do that.

Allan Rutter: 38:46

Well, that is great. And clearly both of you, those answers indicate a sense of purpose and the means by which to make a positive difference. Hopefully this explanation of what innovative intersections will do for our listeners is help them understand and why this is being done in their interest. Thanks to both of you for joining us today, and I really appreciate you being part of our podcast.

Amanda Austin: 39:12

Thanks so much for having us.

Allan Rutter: 39:15

During our conversation, Amanda told us that in Texas, almost one-third of traffic fatalities occur at intersections, and roundabouts can reduce intersection fatalities and injuries by 90%. Given the number of 2023 traffic fatalities in Texas, this means that almost 1,500 Texans lost their lives in intersection crashes. Thoughtful planning for innovative designs can begin to reduce that number of intersection fatalities, one intersection at a time. Thanks for listening. If you liked what you heard or learned something, please take just a minute to give us a review, subscribe, and share this episode. I invite you to join us next time for another conversation about getting ourselves and the stuff we need from point A to point B. 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 host, Allan Rutter. Thanks again for joining us. We'll see you next time .