Latest / Talking Michigan Transportation / Predicting how long a road will last
Transcript
- 0:07Jeff Cranson: Hello, welcome to the Talking Michigan Transportation Podcast.
- 0:10Jeff Cranson: I'm Jeff Cranson.
- 0:12Jeff Cranson: I spoke with Tim Lemon, who is a pavement specialist at the department.
- 0:20Jeff Cranson: He works in the Bureau of Planning and tracks a number of things, doing work that probably most people wouldn't know is even done in the Department of Transportation, which involves figuring out how long pavement is going to last, or at least analyzing data on that pavement to predict the overall health of the system and how much money it's going to take in the future to maintain it.
- 0:49Jeff Cranson: He's really developed quite a bank of knowledge about these things and has a lot of interesting things to say, so I hope you enjoy the conversation.
- 0:58Jeff Cranson: So, Tim Lemon, first time on the Talking Michigan Transportation podcast.
- 1:03Jeff Cranson: I appreciate you taking time to do this.
- 1:06Jeff Cranson: You do, you know, really interesting work, behind-the-scenes work, work that you probably didn't know growing up even went on in the Department of Transportation.
- 1:13Jeff Cranson: I know that, like your job is like so many that I didn't know existed, so thank you.
- 1:20Tim Lemon: Yeah, thanks for having me, Jeff.
- 1:21Tim Lemon: Really excited to be here.
- 1:23Jeff Cranson: So talk about first high level.
- 1:24Jeff Cranson: You know what you do and the trajectory that got you into this position.
- 1:30Tim Lemon: Oh sure, yeah, so I'm the trunkline payment strategy specialist, which is a bit of a mouthful, but really it just means that I work with our regional payment management engineers to develop our investment strategy for the payment network that MDOT owns.
- 1:45Tim Lemon: That's where the trunk line part comes in, and so I basically take their investment strategies that they select during our project selection process, I roll that up into an overall strategy for the trunk line network and then use the resulting payment condition information that comes out of that to share with the state legislature, governor's office, et cetera.
- 2:08Tim Lemon: You know so if you ever see those fun percent, good, fair, poor graphs that get shared all over, that's where those come from.
- 2:17Jeff Cranson: Let's get really into the basics.
- 2:19Jeff Cranson: I guess Did you even know the term trunk line before you came to the department.
- 2:25Tim Lemon: No, of course not Right.
- 2:26Tim Lemon: You know, and talking with friends you hear all about that Like, oh, this road outside their house or this one down the street needs construction or is under construction, and you don't really realize it until you work in the industry that different road agencies own different roads, and so MDOT is responsible for just a small part of the transportation network here in Michigan and we're responsible for about 8% of the highways, the trunkline pavements, while the other 92% of that is managed by about 600 different road agencies.
- 3:11Jeff Cranson: Yeah, and I came to know the term in my former career as a journalist and came to understand what it was, but I still don't know that any other state uses the term trunk line.
- 3:15Tim Lemon: Oh yeah, really I hadn't.
- 3:17Tim Lemon: I haven't heard it myself from other states, but I guess I wasn't really looking for it.
- 3:21Tim Lemon: You know, that's just what we call it.
- 3:23Tim Lemon: Other states it really depends.
- 3:26Tim Lemon: Some of them own quite a few of their roads you know, almost 90 percent, 80 to 90 percent or so while others, like us in Minnesota, for instance, own, you know, just about 10,000 miles or so, which, compared to hundreds of thousands mile road network, is pretty small in the scope of things.
- 3:49Jeff Cranson: Well, and that's something I wanted to get into and that's what confuses people.
- 3:52Jeff Cranson: You're right If you tell people that trunk lines account for 9,700 miles of 123,000 miles of roads, that sounds like not very many, but talk about the traffic volumes on trunk lines versus those local roads not very many, but talk about the traffic volumes on trunk lines versus those local roads.
- 4:12Tim Lemon: Yeah, I mean just despite making up 8% of the actual network itself.
- 4:14Tim Lemon: A majority of traffic in Michigan runs on trunk line routes, 52 or so percent of it.
- 4:16Tim Lemon: And then if you actually drill down into the freight system, you can see that 75% of the commercial vehicle traffic happens along MDOT-owned trunk line routes.
- 4:29Jeff Cranson: Yeah, and that's what obviously businesses depend on more than ever in an age of just-in-time delivery.
- 4:36Tim Lemon: Absolutely yeah.
- 4:37Jeff Cranson: Yeah, so let's talk a little bit about what you and your colleagues do and how that data is used.
- 4:46Jeff Cranson: You said, obviously, that it helps us inform lawmakers and the governor's office so that they can make decisions and they can look ahead to the pavement forecasts.
- 4:55Jeff Cranson: But I guess, at the most basic level, how do you do what you do?
- 5:00Jeff Cranson: And you're not out there actually analyzing the pavement.
- 5:02Jeff Cranson: You're just taking in the data that comes to you and doing that analysis, right?
- 5:07Tim Lemon: It depends.
- 5:07Tim Lemon: Actually, just two weeks ago I was up in Superior Region with my good friend Allison Amlin, the pavement management engineer up there, and I rode around.
- 5:15Tim Lemon: I spent over the course of the week 24 hours in the car just looking at roadways.
- 5:19Tim Lemon: I spent a full eight hours driving around Traverse City and another eight hours in Ishpeming.
- 5:28Tim Lemon: So certainly try to make it out there to all of our region TSC folks to get a better understanding of their pavement situation.
- 5:35Tim Lemon: But, jeff, you're really right that you know I may be helping the regions review their RSLs and talk about the condition, but most of the time I'm a desk jockey, right?
- 5:46Tim Lemon: I'm running those analyses in the office as opposed to out on the road or on the construction site.
- 5:53Tim Lemon: But really the reality of it is what I'm trying to do is help the pavement management engineers understand what rating the roads means.
- 6:01Tim Lemon: Right?
- 6:02Tim Lemon: So we use a condition measure called remaining service life.
- 6:06Tim Lemon: That basically is a forecast of the time until any individual pavement is ready for investment.
- 6:13Tim Lemon: Right?
- 6:13Tim Lemon: So that remaining service life how long until we think that some kind of fix is going to be need to be applied to support the public's transportation needs, and so we generally kind of rate them, as if it has two or less years we would consider that to be poor condition, and then if it's seven or less, we would call that fair, and then anything above seven we would call good.
- 6:36Tim Lemon: So when I say you know, I talk about percent good or fair pavement.
- 6:40Tim Lemon: That's really a pretty broad range in terms of what that pavement actually needs.
- 6:45Tim Lemon: It could be ready for investment in three years, or it could be ready for investment in 26 years.
- 6:51Jeff Cranson: Well, and that brings us to the idea of asset management and the science involved in that.
- 6:57Jeff Cranson: Just like there's a science involved in what you do, I think that MDOT has been a pioneer, kind of a national leader, in asset management, and maybe that's because of incredible ingenuity and innovation and maybe that's because of necessity If you're starved for funding for that long, you have to figure out ways to make the money go farther.
- 7:17Jeff Cranson: And it's caught hold with several counties and cities across the state who now have asset management plans and use that to inform their decisions too.
- 7:27Jeff Cranson: And I know that's not exactly your area, but you kind of get it.
- 7:31Jeff Cranson: Could you talk about that and why a person's basic instinct would be that worst first is the way to go, and why that's not the way to go?
- 7:39Tim Lemon: Yeah, absolutely so.
- 7:41Tim Lemon: You said whether or not it's necessity or it's ingenuity, it will.
- 7:47Tim Lemon: You know, necessity is the mother of invention.
- 7:49Tim Lemon: Right, we have had to stretch our dollar as much as we can to try and provide the best transportation surface that we can for the public, and a big part of doing so is preserving our pavements, not just rehabilitating or replacing them.
- 8:06Tim Lemon: So, as you mentioned, you kind of alluded to that worst first approach would be to just go out when a pavement is ready for investment, go through and reconstruct or rehabilitate it.
- 8:16Tim Lemon: But we have, at MDOT, applied a more preservation-focused approach where we're looking at okay, after we construct something, when is the next time we're going to come back and do a surface seal or a functional enhancement that's going to protect that investment that we just made at a cheaper rate?
- 8:38Tim Lemon: Basically, those preservation fixes, I measure everything in lane miles.
- 8:43Tim Lemon: That's just the way that my brain works now after doing this for so long.
- 8:46Tim Lemon: But you know I measure the cost per lane mile for the preservation fixes.
- 8:50Tim Lemon: It tends to be in the hundreds of thousands of dollar range.
- 8:53Tim Lemon: You know, 300,000 a lane mile.
- 8:54Tim Lemon: Basically, we take some kind of asphalt or sealant mixture and spray it over the top to prevent the underlying asphalt or concrete service from oxidizing and cracking.
- 9:05Tim Lemon: It provides a wearing course for the traffic to cause damage to over time.
- 9:10Tim Lemon: That is really a pretty cheap and effective way to maintain the system, as opposed to reconstructing, which, the cost of which we're seeing escalate not just, you know, over the last 10 years, but over the last three to four years, to record amounts.
- 9:28Tim Lemon: You know, I think last I checked, the cost to reconstruct asphalt pavement tended to be around three to four million dollars a lane mile.
- 9:38Jeff Cranson: So when you're talking about….
- 9:39Jeff Cranson: Sorry to interrupt, but there's a difference between an urban lane mile and a rural lane mile too, right?
- 9:44Tim Lemon: No doubt, yeah, absolutely.
- 9:45Tim Lemon: And that all comes down to the you know, the curb and gutter, the sidewalk, all that stuff you have to get into.
- 9:50Tim Lemon: And so when I'm talking about averages, I do mean statewide right, and typically somebody, like some of the engineers in metro region, are going to have to focus on concrete investment itself.
- 10:07Tim Lemon: So concrete reconstruction tends to cost more than an asphalt in general because of some of those ancillary concerns.
- 10:12Tim Lemon: But when we're talking about preservation versus rehabilitation or reconstruction, we're talking about an order of magnitude more money, and so that's really what I want people to think about when we come back and revisit a road after it's been recently reconstructed is all we're doing is trying to protect that investment over the long term using a cost-effective approach.
- 10:36Jeff Cranson: Yeah, that's very well explained.
- 10:38Jeff Cranson: I think what also people need to be reminded of is that and you know this anyway, but going on the routes you just did, which is really interesting, I didn't know you were out there doing your own observation oh yeah, that almost every city, village, even the unincorporated communities, and it's M-43, it's I mean, it's everywhere there's a trunk line that is a main street and is really important to that community, but it's still owned and maintained by the state.
- 11:17Jeff Cranson: So talk about how, when you drive on these roads, you start to get a feel from, I guess, visually, and maybe from the ride, about that condition.
- 11:27Jeff Cranson: You can probably get to the point where you can predict it, even without the people that actually do that coming to you and saying this is fair or this is good or this is poor.
- 11:36Jeff Cranson: Right.
- 11:37Tim Lemon: Oh, absolutely.
- 11:38Tim Lemon: Yeah, I mean just looking at.
- 11:39Tim Lemon: I mean we'll roll down in the van, we all pile up into an eight or nine passenger van to review these roads and so as we're going down them, people will just shout out a number and we generally can find consensus pretty quickly in the van regarding the condition or at least the amount of time left before we think that something needs to be done.
- 12:00Tim Lemon: Something needs to be done.
- 12:03Tim Lemon: But I have some serious concerns about, just like you said, jeff, how many downtown areas, small communities, are struggling with poor trunkline pavement.
- 12:21Tim Lemon: The Rebuilding Michigan Bonding Program really helped us out by investing a bunch of money into the freeway condition via a bond financing program.
- 12:27Tim Lemon: That obviously has to be paid back.
- 12:29Tim Lemon: But what it did do is help us make improvements to that freeway system now as opposed to having to do it later after additional inflation has set in and additional deterioration has set in right.
- 12:39Tim Lemon: So it gives us that time value of money opportunity there.
- 12:42Tim Lemon: But what it didn't do, unfortunately, was address some of those key downtown small town trunk lines that are folks' main streets to go, drive, to work and back every day down this road and so just going through some of those more rural areas in northern Michigan, I really got to see just what a difference a good you know down Main Street makes to a community right.
- 13:08Tim Lemon: It makes the neighborhood feel different, it makes the community planning feel a little bit more intentional right, because the road is in good shape.
- 13:16Tim Lemon: And so I just I want to express that a majority of our non-freeway trunk line now is in fair condition, which means that it has five years or less before it's considered poor, before our engineers think that, hey, this is going to need some kind of a fix.
- 13:33Tim Lemon: So I mean, we're talking about a lot, a lot of small towns.
- 13:37Tim Lemon: You know local areas that are going to need a lot of work here in the next few years.
- 13:42Jeff Cranson: Stay with us.
- 13:43Jeff Cranson: We'll have more on the other side of this important message.
- 13:50MDOT Message: Even with the best planning, backups and traffic congestion can occur during road construction.
- 13:55MDOT Message: This can pose hazardous situations for both motorists and construction workers, particularly when drivers are distracted.
- 14:02MDOT Message: Motorists are more likely than workers to be killed or injured in work zone-related incidents.
- 14:08MDOT Message: Additionally, the leading causes of all work zone related crashes are distracted driving and speeding.
- 14:14MDOT Message: So it's crucial to do your part in ensuring the safety of both drivers and focusing on your most important task safe driving.
- 14:22MDOT Message: Slow down and stay focused.
- 14:31Jeff Cranson: As you do that driving.
- 14:31Jeff Cranson: There's a lot of misunderstanding that's come forth lately in discussions among lawmakers and some reporting out there that doesn't fully understand how the pavement is evaluated, and it isn't just as simple as a windshield survey, although, from what you're saying, that by itself can be an important contributor to making these decisions.
- 14:49Jeff Cranson: So can you talk about that?
- 14:51Tim Lemon: Oh, absolutely yeah.
- 14:52Tim Lemon: So I mean it's not as simple as a windshield survey.
- 14:55Tim Lemon: You know I contrast our remaining service life measure to the local agencies, the Transportation Asset Management Council, who uses the Pavement Evaluation Service and Rating PASER, if I got my acronym right.
- 15:07Tim Lemon: That rating is truly a windshield survey.
- 15:11Tim Lemon: That you know.
- 15:13Tim Lemon: I don't have anything against it.
- 15:14Tim Lemon: I think that it works well.
- 15:15Tim Lemon: It's just not what we happen to use at MDOT, because our STC goal is in terms of our remaining service life measure, and our remaining service life measure is directly integrated into our asset management process, right?
- 15:27Tim Lemon: How long before we need to do something to address this particular stretch of pavement, right?
- 15:32Tim Lemon: So it's a really good communication planning tool in that way, but it's really not just a windshield survey.
- 15:38Tim Lemon: We go out there, obviously, and raid the roads and talk about what sort of fix this is going to need, but it's not just what you can see with your eyes that makes that decision right.
- 15:47Tim Lemon: It's what's happening underneath the surface, based upon, you know, cores that the engineers are taking, the history of the pavement, the different types of distresses that we're seeing, you know, above and below the pavement surface.
- 15:59Tim Lemon: So all of those things, including drainage and traffic, get factored in by the engineers when they're creating those remaining service life estimates.
- 16:08Jeff Cranson: So, along with the misunderstandings about that also, there's a lot of discussion right now about Act 51, which is the public act, the law in Michigan that decides how the funds are dispersed between the counties, the cities and the state routes, and very roughly, 39% goes to state routes, 39% goes to county roads, 22% goes to cities and villages, and there's a lot of talk about how we need to look at that again and I always equate that to you know, pulling the thread of a sweater, and that when you do that, the whole thing's going to unravel.
- 16:40Jeff Cranson: It sounds really good, but I liken it to Churchill's comment about, you know, democracy, it's the worst, except for all the rest.
- 16:48Jeff Cranson: And I think that's how I feel about Act 51.
- 16:51Jeff Cranson: Everybody thinks this is something we have to fix, and then they start looking into it and find out yeah, you know what I can see why we did it this way and how this all holds together.
- 17:00Jeff Cranson: So talk about your own theory you've developed on that all holds together.
- 17:05Tim Lemon: So talk about your own theory you've developed on that.
- 17:06Tim Lemon: Yeah, I don't have anything against Act 51, I think, and I certainly don't have anything against maybe reviewing and reconsidering some of the decisions that are made by Act 51.
- 17:17Tim Lemon: That being said, act 51 does get reviewed and updated fairly regularly.
- 17:24Tim Lemon: Don't make me pull out my Google machine here but it's not something that's completely stagnant, right, it dates to 1951, that it's ultimately a political device, right, that distributes that revenue across those 600 or so agencies that I mentioned earlier.
- 17:51Tim Lemon: And, like I said, I think reviewing it, reinterpreting it, understanding and transportation needs is all worthwhile.
- 17:59Tim Lemon: It's just, I don't think it's any sort of a silver bullet when it comes to solving the problem that is Michigan's pavement condition performance gap.
- 18:08Tim Lemon: Right, you can spread the money however you like, but it's not going to overcome a $2.5 billion investment gap.
- 18:18Tim Lemon: And then that $2.5 billion that I cited, that's just trunk line need.
- 18:22Tim Lemon: That doesn't even include the locals.
- 18:23Tim Lemon: I'm not, I'm really not meant to be talking about local investment need and, in particular, they don't have a goal really based on pacer.
- 18:32Tim Lemon: But you know, in order to meet our state of good repair goal, it's two and a half billion dollars annually that we'll need to be able to do that and, you know, reworking Act 51 really just is not going to get us there.
- 18:47Jeff Cranson: It's interesting that you say that too, because you've been in this job for a while and you know you talk to family and friends, obviously, about what you do.
- 18:51Jeff Cranson: And what do you say when they say look how much I pay to register my car and look how much I pay for gas.
- 18:58Jeff Cranson: I don't understand why the roads can't be in better shape without getting you know too deep.
- 19:04Jeff Cranson: How do you explain that to them in a few sentences?
- 19:08Tim Lemon: It's just like how much you're paying at the grocery store.
- 19:10Tim Lemon: Ultimately, right, I just had a conversation with this about one of my fellow planners that inflation rate has hit everything, not just that your eggs at the grocery store, but the price of asphalt, the price of concrete and all the sub base and all that stuff that we pour into that roadway.
- 19:29Tim Lemon: All those materials cost a considerable amount of money and the inflation on those has gone up, you know, above and beyond your typical indexes for inflation.
- 19:42Tim Lemon: So really what I tell them is that, yeah, I mean the cost of everything has gone up and we, our revenue, our state revenue, meant for the maintenance of trunk line routes, really has not kept pace with that.
- 19:57Jeff Cranson: Well, and that also that inflation has affected the cost of labor and the equipment that the contractors have to buy too.
- 20:02Jeff Cranson: Yeah absolutely so.
- 20:05Jeff Cranson: What else would you want to get across to people about you and your unit and why you guys do what you do?
- 20:13Jeff Cranson: And while it's out of the public light, it's really important.
- 20:17Jeff Cranson: What would you want to say?
- 20:19Tim Lemon: Sure, I just want to speak to the hard work and dedication that I know that every MDOT pavement management engineer applies, to the hard work and dedication that I know that every MDOT pavement management engineer applies to their everyday work.
- 20:27Tim Lemon: They try very hard to squeeze every last dollar they can out of state funds to improve the condition of their networks.
- 20:34Tim Lemon: We meet monthly to discuss best practices and new technologies that are coming out that we can use to.
- 20:40Tim Lemon: You know, leverage, you know new approaches to pavement management and stretch the dollar even further than we already do.
- 20:50Tim Lemon: So it's not a matter of the will of MDOT to be able to take these important state funds and apply them appropriately to their network.
- 21:00Tim Lemon: It's a matter of the availability of those funds to meet the existing need, and we simply do not have enough yeah, well said well, tim, thank you.
- 21:09Jeff Cranson: I appreciate you uh taking time to do this.
- 21:12Jeff Cranson: I'm sure that uh I'll have you back because I uh enjoy talking about these things too and you break it down, I think, really well for the layman.
- 21:20Tim Lemon: So thanks again yeah, I appreciate it, jeff, and I'm happy to come back anytime.
- 21:25Jeff Cranson: I'd like to thank you once more for tuning in to Talking Michigan Transportation.
- 21:28Jeff Cranson: You can find show notes and more on Apple Podcasts or Buzzsprout.
- 21:33Jeff Cranson: I also want to acknowledge the talented people who help make this a reality each week, starting with Randy Debler, who skillfully edits the audio, Jesse Ball, who proofs the content, Courtney Bates, who posts the podcast to various platforms, and Jackie Salinas, who transcribes the audio to make it accessible to all.