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Trenchless Toolbelt with Mitch Hoeft and Brian Simmons
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Tearing up a street to fix a pipe feels normal until you realize how many better options exist. We go underground with trenchless technologies that let public works teams install and rehabilitate water mains, sanitary sewer, and storm sewer with a fraction of the disruption, and we get honest about the tradeoffs that make these projects succeed or fail.
I’m joined by engineers Brian Simmons and Mitch Hoeft from Bolton and Menk, and we walk through the trenchless “toolbelt” in plain language: horizontal directional drilling for long crossings, pipe bursting for in place water main replacement and upsizing, cured in place pipe for sewer rehabilitation, plus higher precision methods like guided auger bore and microtunneling when gravity sewer grade control is non negotiable. Along the way, we talk costs, tolerances, and the very real mess that can happen when as builts are wrong or utilities are closer than anyone expected.
We also dig into what’s changing fast: better pipe materials like fused PVC and HDPE strings, a growing contractor pool, and emerging approaches like spray in place pipe where surface prep and inspection discipline make all the difference. Then we zoom out to the “owner side” decisions, including prequalification, best value procurement, and delivery methods like progressive design build that help manage risk earlier. Finally, we look at where AI is already useful for condition assessment, sewer CCTV review, and even monitoring HDD parameters to reduce frac out risk.
If you’re a city engineer, public works director, utility engineer, or just trenchless curious, hit play and bring your toughest crossing problem with you. Subscribe for more, share this with a teammate, and leave a review with the trenchless topic you want us to tackle next.
Welcome And Why Trenchless Matters
Marc CulverWelcome to the Public Works Nerds Podcast. Welcome to the Public Works Nerds Podcast, a public works podcast of the nerds, for the nerds, and by the nerds. I'm your host, Marc Culver. Today we're going to go underground, and we're doing it without digging a trench. Trenchless technologies, things like uh horizontal directional drilling, pipe bursting, uh cured in place lining, uh, microtunneling, uh, all of those let us install and renew underground utilities with just a fraction of the surface disruption of a traditional open cut. And for those of us who are managing the streets and the water and the sewer and storm sewer systems, um, those technologies, those processes, they've gone from exotic to essential tools in our toolbox. Uh, but they're also a niche. Um, and getting them right takes the right planning, the right data, and the right people. And I just happen to have two of the right people here with us today. So to help us nerd out on this topic today, I'm joined by two engineers who've made trench lists a big part of their careers. Brian Simmons and Mitch Hoeft, both from Bolt and Menk. Welcome to the podcast. Thank you for having us. Yeah, absolutely. Thanks for the opportunity. Yeah, thanks for joining me. Thanks for agreeing. Thanks for saying yes and for opening yourself up to potential ridicule and and such. You're heard to say no too. But we do that's right. And before I have you guys uh introduce yourselves, I just want to add um in my notes, I just added my homies uh and I I highlighted that. Um, that is the non-AI generated part of the script. Um and I just want to add, you know, I met both Brian and Mitch um when I went over to Bolton Menk uh for a little for that portion of my career. And you guys are two great people, uh, become good friends with you two. Uh, and I really appreciate uh that friendship that we formed. But more importantly, I also appreciate uh the professional relationship we have and the, you know, I call you up with a question, and you guys are happy to help me uh with questions on you know trenchals technologies in particular, um, but a lot of other things too, uh, particularly with Brian. Um we get excited about it, don't we, Magic? Yeah, some a lot of that stuff not related to work, too.
Mitch HoeftYeah, more importantly, which one's more important? I don't know. Right. They're all important.
Marc CulverSo anyway, I just I'm just uh really happy to be doing this with you two and glad you joined us. But let's take a couple of minutes. We'll start with Brian. Uh, why don't you take a few minutes to introduce yourself? Uh kind of you the background of your career. Now, Brian, you this is your third time on the podcast.
Brian SimmonsYeah.
Marc CulverYeah, you about a year ago, almost exactly a year ago, we recorded a podcast on AI and technologies. You and I have done a um a series of presentations. We have done a series of two now. Um, one in Chicago, one in bustling Rochester, was it?
Brian SimmonsRochester, Minnesota.
Marc CulverUm but uh but in any event, uh, why don't you just give it so you people have heard your background, but in case they haven't, give a little bit of background of your background and how specifically you ended up as kind of like this trenchless expert.
Brian SimmonsYeah, uh, I'm Brian Simmons, obviously with Bolton and Menk. Um, I've been doing this for 20-some years. Uh, if for anybody, Marc, that was paying attention, they're probably like, what why is this guy on again? Right. And ironically, the other things that you and I have talked about on your podcast, stuff that I have dabbled in, kind of built, you know, burgeoning things, uh, but the trenchless side uh of the house is where I spend the bulk of my professional career. Uh, I started out as a sort of a traditional municipal engineer, and then uh I went down a path very early on, you know, 05, 06, 07, where I started getting into trenchless engineering when it was a novelty, and it's no longer a novelty. Uh, you know, we can testify to that by the fact that you know Mitch and I are part of a whole group of people here at Boltlandk that focus on trenchless, among other things, but primarily trenchless.
Mitch HoeftAll right, hey guys, uh Mitch Hoeft. Um yeah, you know, like Brian said, um, we've we've been in this industry for a while. And Brian's a big reason I'm over at Bolton Menk. We collaborated a lot. Um, so historically, um, you know, I started my career with some cities here in the Minneapolis-St. Paul area, Golden Valley and Fridley were kind of the start of my career, and I got lucky enough um to work on some of those initial projects in the state. Excuse me. Um more more importantly, I I think the first one was a water main lining project, and it was a collaborative city effort. So we had some out-of-state contractors mobilizing in some expensive uh cost to do so. So um we combined three cities at that time. It was Hutchinson, Fridley, and Golden Valley, and did a tri-city project that was kind of unique. Um, that got me excited about the use of turns technologies.
Brian SimmonsI remember downloading those plans. I still have them.
Mitch HoeftYeah, yeah.
Brian SimmonsMitch and I didn't even know each other then.
Mitch HoeftI think we got maybe an APWA award for that, too. That was kind of cool. Nice. Um, and that led me to uh having in situ form knocking on my door, and they knocked on my door for about eight years, I think, before I decided to join them. Um, so I I got fortunate enough to be um um the Midwest sales guy for In situum. So I got to cover uh Minnesota, Wisconsin, Iowa, and the two Dakotas, um, which ultimately led me uh to Bolton Menk to work with Brian and kind of lead our our trenchless group and develop this this uh new group for the company. So it's been an awesome adventure and uh we're really excited to see where it goes in the future.
Brian SimmonsAlthough Mitch and I have now been told that we we can't we can't call ourselves the trenchless group anymore. We have an official different name, but so we'll behind closed doors just jokingly refer to it as the artist formerly known as trenchless out of Minnesota homage.
Marc CulverWhat's your official name now?
Brian SimmonsWe are the regional sewer water services group.
Marc CulverOoh, that just rolls off the tongue.
Brian SimmonsSo more than trenchless. We do complex collection and distribution things as well. So buried infrastructure.
Marc CulverWell, cool. Well, thank you for that. Um and clearly you guys have got a lot of experience in this area.
Trenchless Methods Quick Tour
Marc CulverSo let's now let's let's dig into it. Let's uh uh let's talk about trench. So first and foremost, um now most of our listeners are nerds, so they're gonna know what this is, but some of them may not. So when we're talking about trenchless technologies, um what what are what are we actually talking about? So maybe we'll start with Mitch, maybe give us a quick tour of these main trenchless methods and uh what maybe each is typically used for.
Mitch HoeftSure. Well, when we talk trenchless, it's it's essentially that it's less trench, right? It's minimal excavation. It's it's a desired construction approach for a lot of reasons. I think generally in Minnesota, we spend a lot of money on pavement and streets. Uh, we got pretty severe weather, um, and it really does a toll on our roads. So we we're constantly replacing our roadway infrastructure. Um, and at times we find these utilities fail um shortly after maybe that roadway was compacted and replaced. And we need a means to replace that utility without tearing up our new investment. Um, that's where translist technologies comes into play. So you listed some here. I mean, a lot of great ones, you know, probably the main ones right away. Horizontal directional drilling, we see it everywhere. Uh, fiber optic companies, private utility companies. Um, it's hard to go a mile down the street without seeing a ditch which uh putting in some small conduit for fiber optics.
Brian SimmonsDid you guys notice you drove by a drill rig right outside?
Mitch HoeftI didn't see you get so used to seeing them, right? They're just in the background now. Yeah. Um, but then you know, so so you got that directional drilling. We use a ton of directional drilling. Um, I think about crossing rivers, interstates, uh, a lot of the municipalities here locally, they're looking at their critical um uh critical pipelines, and that's the ones going underneath interstates, going underneath lakes, going in places where they can't dig it up and fix it if it fails. Um, so we're being proactive in installing new lines using HDD horizontal direct so drilling. A couple other things I want to hit on the pipe bursting. Brian does a lot of this for our company, but that's a really unique one. Um, actually physically creating the ability to upsize a utility in place. Uh, very desirable, I think, about especially locations, downtown Minneapolis, busy utility corridors where there's just not room to relocate it or install a new one. Super congested. Um, HDD can be amazing because now we don't have to find the space. And uh, if we want to upsize that utility, we can typically a couple pipe sizes. Um, you know, CIPP, that's probably my favorite, near and dear one. You know, being that in situ form guy. The IPP cured in place pipe. Thank you. Um, yeah, essentially pipeliner. We're we're pulling in a resin uh plated sock or liner, right? And we're using either ultraviolet or heat to cure and create a hardened liner within the existing pipeline.
Brian SimmonsAnd now we have SIPP.
Mitch HoeftSIPP, spray in place pipe. Oh, wow. Um, probably one of the new ones you're gonna see. You're seeing a lot of culverts now, storm culverts and things, but they're developing products for water mains, quick um um ability to rehabilitate the water main, put it back into service quickly. Um, so spray in place pipes, also a unique one. Um, slip lining. I gotta be the oldest trench list, the first trench list. Um, real really easy, right? We're we're taking a smaller pipe and we're shoving it inside that existing pipe. Obviously, that provides a lot of capacity issues in some projects, but sometimes you um you have the right system. Maybe it was a combined uh storm and sanitary sewer system, and we have the capacity to downsize. Um, two you didn't hit on here, you know, um coatings. We talk about coatings a lot, although it might not be a traditional trench list. Uh, we use a lot of rehabilitation coatings, and I think with structure rehab. So instead of physically digging down and ripping out a structure, oftentimes we can clean, um, prep and rehabilitate the structure in place. So um, I like to hit on the coating piece too, is an important thing. And that buys into what Brian was saying with SIPP. You got any other thoughts on that, Brian?
Brian SimmonsUh no, I I think you're nailing it.
Mitch HoeftUm, and then obviously microtunneling, um pilot tube auger boring, some of the more on-grade accurate transless installations, we use less of those, right? Because the cost is more. Um, but why is the cost more to talk through them?
Brian SimmonsThe equipment is spicy. Okay.
Mitch HoeftYeah.
Brian SimmonsYou know, pilot pilot tube, guided auger bore, all of those things, and micro tunneling. You know, like a micro tunneling machine has to be sized for the pipe that you are either pulling in behind it or building around it. So you know, if if a contractor owns a 36-inch micro tunneling machine, that's what they're going to install is 36 inch. You know what I mean? Yeah. If you spec a project with 24, they're probably going to show up in bid 36. Okay. So the the equipment is is quite a bit more. That makes that a little bit more niche.
Mitch HoeftWell, and just what they're doing too. I mean, so accurate on grade. You think of horizontal directional drilling, great for pressure pipes, for water mains. Uh, we can have six-inch tolerance, you know, um in the installation application because it doesn't matter in a pressure system. But as we get these minimal grade gravity systems, um, some of these other technologies and more expensive equipment packages are needed to deliver that.
Gravity Sewer Grade And Accuracy
Mitch HoeftYeah.
Marc CulverSo to that question, or to that point, we have in Brooklyn Park, we are developing in our northwest area, which has been all potato farms and such uh to date. And at some point, we need to install a sewer line somewhere between 12 and 21 inches. All right, we're apparently still figuring that out. Um uh through the Three Rivers Park District land. And we'd rather not open cut that. That sounds high value, lots of trees, right? Right. And I think three rivers park district would rather us not open cut that. That's fair. And so what but it's a sewer line, you know, and I I don't know what gravity sewer line. Gravity sewer line. Yep. And you know, we we have the we're we're we'll be connecting to uh the Met Council Interceptor, which is just south of 101st Avenue. So, you know, um, and we already have a stub, although it's 12 inches, so hopefully we'll give it a 12 inch. But uh so what do you think would be the best technology in that case? I mean, and I don't know this is all conceptual design right now, of course. You know, they're just lines on paper. So we haven't gotten into the detailed design of what grade uh that would be or what at what depth necessarily that would be. But what do you think?
Mitch HoeftWe kind of plays into your script later to be determined, right? Let's do that preliminary engineering study. What what Brian and I think would tell you is grade's gonna dictate. Yep. Um you have grade to burn sufficient grade, we're still gonna tell you to HDD that thing, right? It's gonna save you tons of dollars. Um, but as an industry, we're looking at percent percent to have minimum, and we like to say two percent really um in our designs to facilitate a good HDD gravity design.
Brian SimmonsSo they have trouble controlling that HDD head tighter than that. Okay, and so then when you rely on the gravity, right, to induce the flow, uh, if you think you're going to install that at you know 10 state standards minimum grade and get the flow that you expect, they're gonna struggle to install that with HDD.
Mitch HoeftSAGs, bellies, you know, you get a certain grade and that pipe's gonna clean itself through there. You're always gonna have a little bit of that, you know, with the HDD press. It's just because the subgrade you're playing through. Um, but we usually strive for a sufficient enough grade that those minor sags and minor bellies aren't gonna hurt you.
Marc CulverSo if I was worried about accuracy and was thinking about microtunneling instead, what would the cost difference be, do you think?
Brian SimmonsUh uh approximately double to triple per foot. Yeah, I was gonna say on the grade.
Mitch HoeftWow.
Brian SimmonsYeah, but but you would start with guided auger bore first, is is the next step I would jump up in in terms of precision of grade above and beyond HDD, and then micro-tunneling after that. And you know, when you're popping back and forth in that 12 to 21 inch, you're in that realm of which one would we prefer to do on the contractor side, you know. So you get into the bigger pipe, you're more likely to get a micro-tunneling contractor that wants to do that.
Marc CulverAnd and I think the part of the the I mean, we're not dumb enough that we don't know what capacity we need. I think the the the ambiguity in it is we don't know what kind of slope we're gonna have.
Mitch HoeftYeah.
Marc CulverSo, you know, if we have a a a smaller slope, um then we need a larger pipe. Absolutely. Um so just for those of you that are critiquing us as well as individuals.
Mitch HoeftFuture projections too, right? That's not an easy thing to do, is put your finger on this is what I want for the next 60 years, right? Or 100 years. Right.
Brian SimmonsI think we can just cover that by saying study pending, right? Study pending.
Marc CulverSo I think that's I mean, that's a that's kind of a great uh example, just kind of talking through some of those different options for a specific uh case. Um, but you know, we've we've said that, I mean, historically these have been kind of like like the script says, a niche uh technology, you know, something that you use when you have to use it. But maybe talk about where how this technology has progressed over the years and and and where we are with that. You know, yeah.
Mitch HoeftWell, you know, Brian and I we we said forever we give a trench list 101 presentation, probably what, three, four times a year. And we we try and do a big picture, we hit on all these technologies and we we provide the technical envelope. Um, you know, it fits this diameter, this install length. Um, you know, we can mitigate through these type of bends. What we find is those are the slides we're changing every year. So uh we get to the end of our presentation, we got this. What would you call the decision tree? The decision tree, right? And it sends you in a million paths, and it can be any one of these things. Um, but what what we're finding is every year, these contractors are challenging the impossible. They're building bigger machines, they're doing longer installs, they're doing bigger installs. Um, so we constantly find this this niche technology is expanding, ever expanding.
Brian SimmonsMy goal in 2027 is to design an intersect HDD drill. That's how they're getting ridiculously long lengths now, or by using two rigs and drilling at each other. Oh, wow. And it it's it's that you've seen the poster with the driving of the golden spike where the two tracks miss each other by a track width. It's it's that, but underground with horizontal directional drilling rods, they they nail the same position and they pull the pipe through a shared void. It's insane.
Marc CulverThat's cool.
Brian SimmonsYeah, but that's how they're getting you know 4,000, 8,000 feet out of directional drills now.
Mitch HoeftGood soils, a lot of wall thickness in your pipe, you know.
Marc CulverOh, is there so at this joint, this meet point, is that an open cut then or something? Or how do they do the handoff?
Brian SimmonsThat's often under the water, very, very precisely. Very pr with lots of precision.
Marc CulverYeah, that's interesting.
Brian SimmonsYeah, so uh, I mean, a lot of these things are are you know, trenchless technologies are the umbrella with which we we shove a lot of things, right? And they are somewhat dependent upon the technologies that enable their installation, and every one of them is a little bit different, or there is some commonality. You know, a pipe bursting machine is essentially an HDD rig that doesn't spin, right? It can just push and pull rods. So some of the the technology is shared. Um, you know, Mitch and I have done projects of of this type sort of around the country, but obviously the bulk of our shared experience is here in the Midwest. And so it's been interesting to watch the contractor pool and the availability of things, you know, speaking to the niche of uh, you know, we bid more HDD projects, and then we'll see contractors that are self-performing. And so then it's interesting to observe who owns an HDD rig, who is renting an HDD rig, who's bringing in a sub to do those things. Uh, and that those those qualifications all sort of speak to whether or not this is the truly niche. You know, when we have easy access to multiple contractors that own equipment or have the ability to run it, you know, then we're getting very competitive bids because the the bidding field is wide open. Right. Um, in addition to the actual, you know, the machines that run the tech, uh, I think pipe materials, you'd probably agree with this, you know, play a big part. Um, a lot of these these trenchless technologies require, and I'm going to use the word monolithic, but but what I mean is is we've got like a string of pipe, right? If we've got a 2,000 foot horizontal directional drill, ideally we have 2,000 feet of pipe laying on the ground somewhere waiting to be pulled in once that drill rod has been all the way through that 2,000 foot drill. And so things like fusible PVC, you know, fusible HDPE, those those plastics and the ability to fuse those plastics. So they all show up as individual sticks of pipe on a truck, right? And then the contractor or somebody hired by the contractor fuses them all together into that 2,000-foot run so they can pull them in. So the materials do come into play as well. And and I would say that you know, we're well past that being a niche, those are all readily available.
Mitch HoeftThey they really are, and that that uniform outside diameter's key, right? Um, you see a lot of trenches applications with certilock or some bell and spigot type connected pipe, right? And what does that mean? That means we got to ream a bigger hole um to accommodate those belt connections. Uh, what does that mean for the city? That means potential for more settlement around the pipe, right? After we install that. So if we can get that reamer just slightly bigger than a uniform um outside diameter pipe, we minimize a heck of a lot of settlement and a lot of problems for you guys as the end user.
How Trenchless Keeps Expanding
Marc CulverCool. That's all good stuff. Um looking at my scripture, wondering how we transition to um we'll talk about pipe bursting a little bit.
Brian SimmonsSure, sure, sure. So pipe bursting uh has the advantage of using the existing line and grid of a pipe that's already in the ground. Um, I will say this sort of came into vogue because of all the cast iron water main that is is failing around us. You know, yep, yeah. It's tons of tons of six-inch undersized, even some four, I hate to say it. I've run into it, you know, but but cast iron inherently is it fractures very easily. It's somewhat fragile. And so when you run a cutter head through it, it's very easy to blast that open and you can you can use a a uh you know, sort of star-shaped cutter head to shove those chunks into the surrounding soil, and then you make a void into which you can pull a new pipe. And when Mitch talks about upsizing, you know, what I would tell young engineers when we're we're mentoring these kind of things, you can maybe go up two pipe sizes, and there are a lot of of caveats to that of uh, you know, what how close are we to the the nearest surrounding utilities and things like that? But we can get from that, you know, six inch maybe up to a 10. Wow, and so we can replace a six-inch cast iron with a piece of 10-inch PVC. We've stayed in the same place, assuming you know you're deep enough and it's not it's working well, there aren't any bellies, sags, things like that. Um, and so we pull that new pipe in where we have fractured the heck out of that existing pipe.
Marc CulverWhat's your biggest horror story on a pipe burst project?
Brian SimmonsUh you cannot burst things that will tear. Uh, there are, and this is you know, Mitch was talking about a minute ago, slides that we are editing because contractors are doing new and crazier things all the time. They are now getting to the point where they can burst ductile iron. You know, duct ductile is it's in its name. You know, the ductility of the iron, it doesn't fracture. Uh, but using newer types of progressive rolling cutter heads, they can actually score lines into it and make it rip into strips, essentially. Uh, but we did a pipe bursting project where we tried to pipe burst some um corrugated metal, and that doesn't work. It didn't work well. Nope. It bunched up around the cutter head and it eventually caused a sinkhole in the middle of a county road. So that was something that a contractor proposes an alternative that we Sort of observers on. We did not design that, but that was a good lesson learned.
Mitch HoeftYeah. You know, another thing with that is is your depth, right? Uh, we did a project when I was working for Golden Valley and we were doing a shallow uh storm sewer upsizing. Um, I can't remember what pipe material that was, and I think that was a three-time upsize. So we were really pushing the envelope with the technology, but this pipe was only like three feet deep, right? So we knew we wanted to install it this way, but we knew we were gonna have a lot of surface displacement, right? Those forces oftentimes are pushing up. So you think about your gopher mound, right? Um, traveling along the direction of that pipe that we just burst. So in that particular project, we knew it, right? But but that's what happened. And so we had to bring a skid steer in afterwards and kind of regrade and reshave and reseed on top of that soil. Um, so you know, the surface displacement's a real one. You get to a certain depth, and that soil depth can accommodate that compaction of that pipe. Um, but when you're too shallow, that's gonna go up the point of least resistance, right? You may have some surface impacts from the pipe bursting if it's too shallow. So that's something to think about too.
Brian SimmonsWhen we were brainstorming this recording, I think one of the things I emailed you was uh your as built suck, and now we're gonna go pipe burst from them. That too. Uh that's on here somewhere. That was that was based on an experience uh where we planned to pipe burst a force main, a cast iron force main that actually was installed in a shared trench with uh mostly clay tile gravity sanitary sewer. And so all of the investigation we did ahead of time indicated that those things were, I don't know, eight, nine feet apart. And then we dug the trench to insert the bursting head and we started bursting, and they were only three feet apart. They were in a shared open cut trench when they were installed in the 60s, and so you know what happens to clay tile, game changer, it just starts cracking, and then you just start chasing the cracking, and so then unless you want to open cut replace all of that sanitary sewer, we had to shift, and so sometimes our pipe bursting projects become horizontal directional drilling projects in a hurry, yeah.
Pipe Bursting Upsides And Failures
Mitch HoeftOr potentially lining projects, or potentially we've got we've got some of those too.
Marc CulverYeah. Well, and and and maybe talk through that a little bit. Like when you would like say somebody's got a you know, a six-inch cast iron water main, and you know, they're having issues with it, and the options are doing some sort of lining or like a pipe burst type of sure. Now, lining and water mains, I know when I came when I went to Roseville, they had a horror story of a of uh a water main lining project that they tried to do on Rice Street. I think it was an emerging 3M uh technology at the time.
Brian SimmonsOh yeah, yeah. We're familiar with that disaster.
Marc CulverAnd it didn't came and went quickly, yeah. Yeah, so maybe talk about the advancements in because we've all accepted, we all accept you know the CIPP, and when we think about that, we think about sanitary sewer lines, yeah. And and everybody's doing that. Yeah, cheap. And it is more cheap, and it's be it gets cheaper and cheaper. Just kind of like our conversation with uh drones. We we had before we started recording this. As more and more people are doing it, more and more contractors are doing it, um, and there's less risk with it, and this, that, and the other, the cost is coming down.
Brian SimmonsAbsolutely.
Marc CulverSo, where are we on the water main side of that?
Mitch HoeftI'd say, you know, water main, it's just it's more expensive, right? You get a watertight, pressure tight system that has a lot different testing criteria when you're done. It's a lot harder to deliver that. Um, in the CIPP world, you know, we have products available for that. It's it's different resins. A lot of times, the thing with pressure pipe is you get a tensile force, right? You got this this force inside the pipe pushing out, trying to wreck the pipe. Normal gravity liners aren't developed to sustain more than maybe 10 psi. Oh, okay. So um you're you're switching products, you've got epoxy resins. So the they're you know, you can go through it, NSF, potable water, so they got to be epoxy. They've got a fiberglass or carbon fiber component to that liner, too, to help with those tensile or those burst pressures. Um so you know, just much more costly. You you think about, you know, an eight-inch uh gravity sewer line might be 35 bucks a foot. An eight-inch water main line is gonna be 125 to 150 dollars a foot, you know, for the same same same similar product. Um, but there is a lot more manpower and a lot more time. You know, you think you pull up to a structure for sanitary, your liner goes down the structure throughout the pipe and you cure it. Uh water man is just tougher, right? We gotta dig it up, we gotta access it, we gotta, you know, flush it, clean it.
Brian SimmonsUm the accesses are way more difficult. Yeah. I think with the manholes. Right, right. You don't you don't have structures. Yeah, I I find it interesting to watch how the projects around us and and the ones we've participated in too have have evolved. You know, um back when you were talking about, you know, the 3M, the Scotchcoat disaster. Uh, and and even now, the reinstatement systems. So the ways that these water mainlining contractors go in through the pipe and reopen the individual water main services, if it has services, most of those are all still covered with patents. So everybody has sort of their own proprietary system. I will say at this point, all of the ones that are competent at doing it, they're all having about the same success rate. But also when we design those projects, we are still planning in, you know, a certain percentage of failures. Yeah. Assuming that one that is reinstated from inside the pipe is either not going to be reinstated and we're going to have to open cut, or one is going to be reinstated and then leak, which means we're also going to have to open cut there to fix that leak and then reinstate that service.
Mitch HoeftMight be I was just it might be the type of connection too, right? A metal type of connection or how that that service is connected to the water main might determine our ability to successfully reinstate that. And that's always a tough thing for the contractors is showing up on a job and not knowing that, right? And then finding it out when they're under contract. And ooh, I'm not sure my 90 to 95% success rate applies here, the way these connections are. So that's a real real thing and something that could be, you know, explored with your public works group um throughout the design of the project, just to understand what those risks are. Yeah.
Brian SimmonsI also look at the way that some of the larger water system owners around us handle water mainlining projects. Um, if you drive through South Minneapolis right now in the area of Minnehaha Creek, I'm sorry, uh Minnehaha Falls, you'll drive by a whole bunch of 96-inch pieces of 96-inch corrugated metal pipe that are about six feet long and they're sitting on the sidewalk, and then some of them are already inserted into the street, and it's the Minneapolis water. They use their own excavating crews. They go out and they establish those accesses. Uh, and and I don't have first hand knowledge of this, but the benefits that I see are that now they only have a contract with one contractor, and that's the water mainlining contractor. They don't involve another, you know, a sub to do the excavations. And in Minneapolis, a lot of times they'll also handle their own, you know, street restorations. But so then they also focus that contractor, you know, when they provide those accesses, that contractor can get in there, get into the water main, get it lined, and get out and get reinstated. It the process goes much quicker, and I'm sure they have much happier residents because of it.
Mitch HoeftThe contractors love it too, right? They want to show up and line the pipe and get the heck out, limit their risk. So Minneapolis, St. Paul Regional Water is very similar, right? And Minneapolis got a lot of steel water main, and they've got a lot of very talented welders, right? To put this stuff back and uh they just say, no, we we don't really want a contractor working on this, we'll do this ourselves. And I I think it does save them a lot of capital on their projects. Um creates you know the need for more staff.
Marc CulverUh yeah, but it's less risk.
Mitch HoeftCorrect.
Marc CulverYou know, you don't you know you you know what you're gonna get as far as experience and ability with the contractor or the people that are doing the work.
Mitch HoeftAnd it can vary depending on who wins,
Water Main Lining Reality Check
Mitch Hoeftright? Yeah.
Marc CulverI I chuckle because and this isn't a uh a trenchless technology story, but I I just chuckle because we recently had a experience with a contractor who was just replacing a I mean it was a 24-inch water. I mean, it's it's no cakewalk necessarily. That's a lot of water, but uh they they clearly didn't know what they were doing, and we had to have uh, I mean, we had our guys in the trench showing them how to put the fittings on. Oh boy, you know, so that's and but to your point, that's that's what you're avoiding is that risk of hey, we got the little bitter, he's come in, they're coming in. You have no idea who these people are that are actually working on this, right?
Mitch HoeftOn this, luckily for us in in some of these trench list industries, we do know the contractor, right? Because there are still a fairly limited number, and they're maybe mobilizing across multiple states to get here. So you kind of know the players. Um, but as Brian said, it's like HDD, we're starting to lose that, right? Because everyone's getting involved. CAPP is still a little more, especially on the pressure side, a little more maybe technical, and we don't have as much competition, but uh that's changing quickly too.
Brian SimmonsYeah, one of the tools that we will use in bidding projects to try and minimize the risk is is developing lists of pre-qualified bidders. But also, to be fair, when you have a list of pre-qualified bidders, you also have to publish a process for someone to make it onto that pre-quall list. How do you become pre-quall? Yeah, and so you know, we can't do that right now for horizontal directional drilling because we get bids that come out of the woodwork. Yeah, and and sometimes even if we publish a pre-quall, you know, we'll get a contractor that tries to meet it with a hundred thousand feet of two-inch conduit because that's what they've been doing is flogging their HDD rig, installing two-inch conduit for fiber. Um, then we get to decide is this contractor ready to install 10-inch water main, yes or no?
Mitch Hoeft24-inch casing underneath the interstate with a two-inch experience. Probably not, right? Yeah, uh, but but how do you get these guys involved? Because oftentimes this is how some of the best contractors are developed, right? They wanna they want to achieve more in what they're doing. So Brian and I are always talking to new contractors, finding maybe projects with minimal risk, uh, something that they can maybe give the city a good price on and get some experience in um and in a location where they're not going to do you know more harm than benefit, uh, as they learn some of those lessons.
Marc CulverIt's a good, it's a good uh observation about developing giving contractors an opportunity to get that experience you know, while still trying to minimize your risk as the owner.
Speaker 3Right.
Marc CulverYou know, and and theoretically, you know, you would think that you know that the the contractor that has less experience are gonna bid lower, you know. Typically do. Right. So how do you balance that? And I know like in Roosevelt, we had implemented a best value uh bidding process for more specialty work, and I would certainly consider this specialty work, yeah, you know, but for like some of our lift stations and things like that, we were using like a best value process, and you know, that's where we could look at we would give a contractor points for experience, um you know, understanding of the project, maybe even some value engineering of the projects and things like that. Sure. Um and then and then obviously there'd be a bid price, and you would balance those two out. And a really well-experienced contractor that brings extra value to the project could get the project while still bidding more, yeah, you know, not being the lowest bidder. But that then that kind of pushes out the newbie. You know, and how does the newbie get sure um that experience? And maybe that maybe that is really hey, go work with the prime contractors on some larger jobs, get some experience, some things like that, and then come to us as a general on a project.
Mitch HoeftBut it could be, or you know, it could be a small emergency repair that needed, and the big guys are busy and they're not supporting you, right? And you have to have to take the opportunity to get to one of the small guys in there. That'd be a way. Yeah.
Brian SimmonsWe're we're blessed with a pretty, pretty talented contractor pool in in Minnesota, but also that means that we've got some primes that are willing to take on some of that risk. Uh, and and they seem um, you know, more than willing to bring some of those newbies, you know. Uh Mitch and I we do our best to try to track the who's who, you know, but you can't always keep track of you know who who and their brother-in-law decided to leave the firm that they were at, go buy an HDD rig and pop up somewhere else, you know, with a new name. You know, we I could probably list the number of times that that's happened in the CIPP world on on one hand, and and we know exactly who they are, but it's when somebody whose name we recognize pops up on a proposal under a different company name, you're on the phone going, hey, what gives here? You know, uh who is this new firm and how are you claiming experience? You know, so also building when we were talking about you know project controls and having those pre-qualifications, uh, writing those pre-qualifications to be fair. Yeah. Right. You know, at at twenty if you're you've got a 12-inch water main project, you know, 10,000 feet is probably a more than generous number. If a contractor can meet that, they've already shown some competence, even though that's you know, not decades necessarily of work, if that makes sense. Uh, you were talking about best value procurement. I think that trenchless projects in general lend themselves to all of the alternative delivery methods. Um, so you've got, you know, and I'm gonna rattle off some acronyms, but you write CMAR, right? Yeah. Construction manager at risk, you CMGC, um, you've got design build and progressive design build. Um, myself and and a little bit of Mitch, uh, this last year we had the privilege of getting to work on a force main project that was progressive design build. And that's very interesting because then we were on a team with a contractor. And so then when we had questions about nuances between these different trenchless methods, instead of having to structure that in a way where we maybe asked multiple contractors and we didn't tell them where it was, you know, or we paid a contractor to do a peer review and then we had to exclude them from the bidding. We didn't have to do any of those, you know, non-collusionary sort of protect ourselves practices. You just pick up the phone and you say, which would you prefer here? Yeah, and we talked it out. And so I think that alternative delivery speaks really well the trench list project.
Marc CulverSo, and and this isn't the topic of this podcast, sure, but um maybe highlight the differences. And I I would well, the difference is the major difference between progressive design build and traditional design build. I we actually did a podcast way early in the uh uh evolution of this of this podcast. We did an episode with St. Paul Water, yeah. Um and uh Pat. What was Pat's last name? He was the general manager of St. Paul Water at the time, and then he moved on to a place down in Florida.
Brian SimmonsBut um But it still is Pat's last name.
Marc CulverBut uh they use progressive design build for the um expansion of their water treatment facility. Sure. St. Paul Water. And so we he kind of talked through that process, but just as a quick highlight of that differences between the two.
Brian SimmonsSure. Well, I guess maybe uh though those methods you know require a different contract structure from the owner. Yeah, right. And so then instead of hiring an engineer, doing a bunch of planning, maybe some design and putting out a set of plans, you hire a team, you know, where the engineer that at the very beginning, where the where and and there are nuances obviously between CMGC and C CMR and you know who's responsible and who ends up in that prime seat. Uh, I I know for our uh for us, the the switch in you know who's paying my bills, you know, we're we're then rolling up to a contractor team, and that contractor is paying our bills after they are paid by the owner. But also, we still have the same responsibility that we have as an engineer to the public to make sure that we are responsible with public money, you know, so we keep the budgets and all those things, and we design something that is responsible for public use. So, so our level of care doesn't change. It's more of a contractual setup. And so then, like, you know, design build versus progressive design build. Um, I after having lived through a six-month project, the progressive design build, we started at 30%, and we had six months to bring uh essentially like a $12 million project from 30% to 99%. And and we did that with a pretty fast and heavy burn rate. Uh, but then there were uh a 60% a GMP, a guaranteed maximum price, and those are off-ramps both for the contracting team and the owner. Yeah, so when the when the contractor is using the design as it is and putting together a price, then they get together and everybody gets the chance to say, I want off the bus. And and in this case, they did not.
Speaker 3Cool.
Brian SimmonsSo I yeah, I I definitely not what this podcast is about, but I I would be remiss if I didn't say that we're seeing more of that.
Marc CulverSo the progressive design build.
Brian SimmonsYeah, yeah, yep, yep. And so, like when Mitch talks about that decision tree, you know, we have a version of that that's all branded but being fully transparent. That decision tree is a is an AWWA document, the M21. And it was it started out as a uh decision tree for how to rehab water mains, and we've added on to it, you know, we've we've turned it into a tool we use for a lot of things. But when you when you answer the questions, you know, is this a transmission main? Does it have services? You know, can you handle a reduction in diameter? All the things that include or exclude the different trenchless methods, when you get to the bottom, you may still be left with four or five things that work. And so then you even if you've eliminated a couple, you know, you might then have to go into the actual engineering process. And that's where maybe we're going to talk a little bit about um how we like to structure trenchless projects and and what we like to do ahead of time or at the beginning of a project. But um you've you've got the ability to say, uh, you know, this is you bring together this is the contracting pool, you know, this is what we know about material prices, this is what we know about you know, time of year. Like you can you can line almost year round, right? So that versus if we've got to do some open cutting, now we have to deal with some frozen ground. So um bringing all that together, you may still be left with a bunch of options to navigate in the trenchless world.
Mitch HoeftAnd sometimes we'll we'll bid multiple, we'll design it bid multiple options too, not knowing contractor availability or equipment availability. Um, so then it it asks a little bit more out of the design engineer, but sometimes you got to think through multiple designs and bid uh bid a couple as an alternate and then select one after, which is kind of a cool strategy.
Brian SimmonsAnd that's one of the reasons why I say I enjoy the alternative delivery is because we can we can cut to the quick with that. You know, a contractor that's on that we're on a team with can tell us, yeah, oh, I'm never gonna do that
Bidding Prequal And Delivery Options
Brian Simmonsthere, you know.
Mitch HoeftCorrect, correct. Um I'm just trying to look through what other what other one of the things that was on here, you know, talking about the general benefits of open cut in in places where open cut or benefits of trenchless and places where open cut still wins, if you want to have that discussion. Yeah. Um obviously, you know, open cut's still critical. We need open cut to support virtually every trenchless application. We do. Um, so we don't shake a stick of that either. Um, I I think about municipalities here. Um, I think this is a question later too. What drives does the utility work drive the road construction or does the road construction drive in? I think it it really depends, right? It um I think usually the utility reconstruction is gonna drive where you do your roadway.
Marc CulverIf you're smart, yeah, if you don't like digging up new pavement, I let's let's hit the pause button and rewind a little bit on that. Because I would say in Brooklyn Park, our road projects, our roadway condition has really been the overriding factor on when we do a project, and then that also because we're tearing the road open, oh, we're gonna open, we're gonna replace the water in the sewer.
Brian SimmonsDo you look at do you look at that two, three years before the payment project though? Like, is there an opportunity to line some storm sewer and not replace it?
Marc CulverWe should.
Brian SimmonsThat is a thing we could we could explore.
Marc CulverAnd and I'm pushing my staff a little bit. Like we don't do in my opinion, we're too quick to just automatically replace, open cut replace our sanitary sewers in particular. Yeah, because you know they typically are deeper. Um, but the reason we do it is because we're also we own, and I think this is not the best way to do it, by the way, but we own our services up to the right-of-way line.
Brian SimmonsYeah. But there's every different flavor of that.
Marc CulverAnyway. Yeah. I mean, in Roseville, the the property owner owned it to the Y, to the main.
Mitch HoeftYeah.
Marc CulverAnd because we own it to the right-of-way line, we then are proactive in replacing, you know, when we're when we're reconstructing the street and we've got everything open. Well, we open it further.
Brian SimmonsIt's open now. It's open now.
Marc CulverYep. Um, we dig down and we replace the sewer main and the services up to the right-of-way line. And I I understand that to a point, but we're spending a lot of money doing it, and it's very disruptive. And it creates a really big mess uh for every reconstruct project that we do. So I'm pushing them to think more about uh lining our sewer sewer mains more and asking the question do we really need to replace the services?
Mitch HoeftYou think think of the dollars and cents, and I I think there's a lot of communities where you're gonna get a little off is your services. We'll talk about that, but um open cut sanitary sewer, what are we talking? 60 bucks a foot, something like that, new PVC. Yeah, if you want. Um, no, you can line it without digging down and disturbing that soil for 30 bucks a foot, 40 bucks a foot. So you are seeing more cities making the switch on sanitary sewer, and maybe they're lining their sewer in advance so that they can dig next to it and get to their water during their street project. Um, where it's going to hit you is that service cost, right? Uh, we have lateral lining. LMK developed some BLD, Trelliborg, there's a handful of companies, but they have these T liners, lateral liners that are installed liners. From the main up the lateral. Um, great products. Uh but how far can they go?
Brian SimmonsWell, that's just it. How much do you want to pay?
Mitch HoeftTypically about 30 feet without a clean out, and then they need a clean out to assist themselves in going further.
Marc CulverWhich we should probably put a clean out anyway. If we're replacing the dang line anyway, yeah.
Mitch HoeftYeah. You don't have one outside your house somewhere. Hopefully. So you have to don't have to drag that equipment in your basement. But some some utility owners will look at more cleanouts and more of those places you cut into the surface is just another place for infiltration and routes and things of that nature. Um, but these lateral liners, we talked about patents, uh, king of patents, right? These guys, they're limited contractors, they own the patents, and these products can be very expensive. So the money you save lining your main line now, if you want to line your laterals to the property, that can be a pretty expensive endeavor. So you're probably forced at that point to you know do a collaborative approach where you're lining the main line and then digging down to each service. Does that make sense? Maybe it saves you a little bit. Um, but I agree. I think you're seeing more and more cities, uh, especially with the cost effectiveness of CIPP in the gravity world. Let's just line that sewer in its grand place and and not go get it. Yeah.
Marc CulverWell, that's good. I'm I'm glad we had that conversation because I've been, like I said, I've been talking to my staff more and more about that.
Brian SimmonsUm Marc, one one thing that I you know, I don't remember who said this phrase first, actually. And it may have been you, may have been me. I don't remember. It was a conversation that we had though, that asset management is a mindset, right? Not not just a program. And I don't want to take us on that tangent because that's not what we're doing here today.
Marc CulverBut the asset management conversation is about asset management.
Brian SimmonsRight. No, it needs to be in the background all the time, constantly thinking about what condition are our things in that we cannot see, right? And and that that asset management mindset drives a lot of the condition assessment that we use to make decisions about trenchless tools or trenchless methods. And so, you know, if you're gonna look at can we line these things in the year or two before a street project, you know, that asset management mindset is is really where you I think you want to be of of doing the analysis and knowing when the that's okay. I think the pavement is the the thing that people drive on. So they feel it if the ride is bad, they see it if the road is crumbling.
Marc CulverSee it. Yeah, it's yeah, yeah, the easiest thing to rate condition-wise. Absolutely.
Brian SimmonsYeah, absolutely. And then all the other stuff is out of sight, out of mind, right? And so, so bringing the the asset management mindset and the condition assessment into you know your capital improvement planning process, then using that to drive trenchless tools.
When Open Cut Still Wins
Brian SimmonsYeah, I I think is is a good place to acknowledge we want to be.
Marc CulverYeah, well, I think that's well said. Um, two quick things, two more things I want to hit before we start wrapping up. Um one, so we we at the beginning we kind of threw in this spray in place pipe. Yeah. So for water maids. Um I really want to call it an Ice P roll up here. Say that again, Brian. The microphone I might not have.
Brian SimmonsI don't think I only get I only get one shot at that. Only get one shot.
Marc CulverIt's like saying Mississippi. Yeah, really, really fast.
Brian SimmonsYep.
Marc CulverUm but okay, so where are we seeing that? And where maybe I I obviously that's a newer emerging technology. Have you guys actually seen it? Yeah, and where have you seen it work and where have you seen it not work?
Brian SimmonsCan I talk about storm tunnel lining? Sure. Yes.
Mitch HoeftIs it different? Yeah.
Brian SimmonsSo so I've used it on a handful of projects already for fairly large storm tunnel lining. Okay. So and it it's in a case where it would be cost prohibitive to CIPP. Yeah. Because CIPP has to be manufactured somewhere else, or at least portions of it have to be manufactured somewhere else and then brought together on site. And so when you get to the point where the the tube itself, the delivery method for the liquid resin is just too big or too heavy.
Marc CulverBut would you what's that size?
Brian SimmonsUh what's that break point?
Mitch HoeftIt's gonna depend on the length. Yeah. Uh, but typically I would say so you get up around the 48-inch pipe, and then it's really gonna depend on the length, right? How much how heavy is it? Yeah, how can you physically truck this across the roads with certain restrictions on them?
Brian SimmonsIt's it's less common, but we have had projects where they will do what's called an on-site wet out over where they'll they'll bring, yeah, they'll bring the resin in a tanker truck, so the actual materials that become the fiberglass pipe, and then the the tube itself will be you know on a truck dry, and then they'll they'll put the things both things together over the hole as they're pulling it into the pipe. And that's sort of the upper limit of like how can we manufacture a CIPP on the spot where it's too heavy for us to truck in and there's too many materials or it's too long. And so then the SIPP, you know, all they have to do is get the sprayer or get a spray casting machine into the pipe, and then we can have tanker trucks of the spray materials, you know, assuming they're most of the ones I've done are two materials that they're gonna mix together at the gun for um activation.
Mitch HoeftI think the important part for SIPP is pipe wall prep, surface prep, right? Because we're relying on adhesion, whereas a liner we're inflating and we're encapsulating that resin, so we're holding it together and creating a pipe. SIPP only works if you have that adhesion to the existing pipe and you build up a thickness, a layer that we can quantify a strength from. Um so that's the biggest dynamic between the two. I think both of them work very similar. The liner that felt gives it essentially no strength, it's just to hold that the delivery method, right? It's it's like your buns on your sandwich, right? To hold the good stuff you really want. Um, you're really thickness to create your your pipe wall and your strength, right? So both technologies are very similar in ways, but their application is different because of that adhesion. Adhesion is a tough thing. We do a lot of manhole rehab. Uh, the guys that do really well spend a lot of time cleaning, drying, prepping that structure to take the coatings. The guys that do not, um, they're washing it one day, they're climbing down there an hour later, they're throwing coatings on, and they're falling off a year later.
Brian SimmonsLack of prep, number one cause of failure.
Mitch HoeftClients calling us, like, well, what the heck happened here, right? And it's uh it it just speaks to the construction inspection piece and having some representatives out on site during some of those critical pieces of that installation.
Brian SimmonsI want to know what SIPP you were going to talk about.
Mitch HoeftI was gonna talk about just unique applications. So I think about our our water wastewater group. We we develop a lot of uh structures, buildings, right? Where we're we're processing treating water, uh, discharging water. Um, we got a lot of concrete and we got pipes running through these very expensively poured concrete walls. And once in a while you get a pipe joint that may leak. Uh, water in, water out. And the only option historically has been, well, we've got to rip out that concrete wall to get that pipe out and replace it. Where I've used SIPP is um pretty unique tools, right? The guys can carry this stuff in in their briefcase essentially and um get it into the pipe from the inside of the building, take a few bolts off, take an elbow off, shove it right in there. Now I'm gonna maybe coat 40 feet of the pipe coming in and out of the building to seal up the leaks at the joints. Let it cure, pull that, put the pipe, you know, that elbow back on, bolt it back on, and you're good. We just saved a heck of a lot of concrete replacement. Um, so I've used the tools uh that way um a handful of times now. And these contractors are able to essentially hop on a plane with this equipment um and uh and get here and do those installations. So another another unique application for it.
Spray In Place Pipe And Prep
Mitch HoeftWell, good.
Marc CulverI look forward to maybe hearing some more about that, and hopefully the the cost comes down on that, another tool we can use.
Brian SimmonsLocal contractors with the equipment now.
Marc CulverYeah. All right, so I I feel like we talk about AI in every podcast I do now. And we I used AI to generate most of this uh script and such today as well. I'm using it more and more, and I'm I'm kind of afraid to say that, but or hesitant to say that. Thank you, Skynet. I think it's great. Is AI having any role in trenchless technologies?
Brian SimmonsUh can we should we talk about sewer AI again?
Marc CulverSure.
Brian SimmonsYou know, I we were just talking about condition assessment and how important that is for selecting you know trenchless tools or rehab tools. Uh we are subscribers to sewer AI, and and I will say caveat, sewer AI is just one of multiple, yeah, uh, including IT pipes. Uh there's a number of technologies exactly like this. Win can, I'm trying to make sure I hit as many as possible so I don't sound like I'm shilling because we we pay to subscribe to sewer AI, but what we get out of that is we shortcut the condition assessment process on uh televising of pipes. So instead of someone having to watch that and maybe more than once to do a NASCO condition assessment, that person then just has to go in and look at the way AI has summarized it and whether or not they agree or disagree with the condition rating. But that lets us consume a whole bunch of televising very quickly and get to some basic recommendations, even though human intervention is required. Uh, and in this case, so what's the term we like to use? Engineering judgment. You know, we have to apply our engineering judgment to decide whether or not, you know, this type of rehab is is right. So they didn't, they're not handing us the solution, but using that as condition assessment again as part of your asset management mindset. Um, AI is is helping us that way immensely.
Mitch HoeftBut it's imperative. I mean, I think at Golden Valley, small little community here, right? We had about 120 miles of each type of utility just in that small city, right? So think of the manpower to sit, you know, at a 15-minute clip to get 300 feet down the pipe to kind of watch all that, right? We're talking about creating positions of people just to keep up with this pipeline integrity and management piece, right? So sewer AI is a really cool tool. Um, other places I've used it, I've had it running some pretty um um pretty interesting thickness calculations for my CAPP liners. You know, ASDM's developed um different ways that uh we can look at these liner calcs and how thick they should be. Um it's uh we've developed some of our internal calculators, but those are constantly changing. Now there's a whole, I'm trying to think, I can't remember the name, but there's uh essentially uh a new liner that looks at the close fit nature and it takes into account that existing piping and it runs a whole different calculation. So AI is actually pretty good. If you tell it tell it, I want ASTM F1216, I want to run it on this pipe given these constraints, it'll give you an accurate number that matches up exactly with their calculator. Um but it's it's allowed everybody to run those calcs. One of the things in the lining industry is I think the contractors got over on some of the cities, is you know, it's a very competitive industry. And I'm not gonna most don't do it, but there's contractors out there at times I think that thin up those liners a little just enough to get get that winning bid. Um now with AI, any city representative could check those submittals and understand, oh, yeah, this is the thickness I need. You're actually giving me this. Upsize it, you know, I need more.
Brian SimmonsSo maybe another millimeter and a half lift.
Mitch HoeftYeah, and they're accurate. So we we've been playing around with it just to see how it compares to our stuff, right? And make sure it's accurate. Um, but it's good. And it'll provide some detailed calculations you could print out for submittals too.
Brian SimmonsOne very cutting-edge thing that I have not used, but I saw demoed at at the no dig conference, was it which is the NASTT, the National Association.
Mitch HoeftGive a plug for Raleigh now.
Brian SimmonsYeah, yeah. For sewer and trenchless technologies, uh, which by the way, no dig is going to be at the end of March in Raleigh, North Carolina this upcoming year. I presume Mitch and I will be there. But this is this is where we are connecting and interfacing with you know all of the people and the organizations that are doing these cutting edge things. And at No Dig last year or in 2026 this year, um, I saw demoed a way to monitor an HDD drill rig, and they were looking at you know pullback forces along with the bore pressure, which is the pressure of the you know, the bentonite, the drilling mud that's being used, and they were monitoring that in real time to model the likelihood of a frac out. And so, well, pieces of that aren't AI, right? They're just a math equation, an algorithm, but running it in real time and being able to connect multiple variables that they were then pulling from sensors, you know, uh ambient weather data, things like that, and then model the likelihood of a frac out to try and minimize that.
Marc CulverCool.
Brian SimmonsYeah, I thought that was really neat. I'd love to try it sometime.
Marc CulverI will also add just off of what you said, I think there are a lot of it's kind of like the old 5G thing, there are a lot of uh processes and such products that are claiming AI that are really just really well-defined algorithms, sure, you know, um, and there's a difference. There is a difference. Um but in any event.
AI For Inspections And Safer Drilling
Marc CulverWell, cool. Uh well, this has been great. This is this has been a real nerdy episode. Um, nothing less from you two. Uh any final words that you want to say uh about credentials technologies?
Mitch HoeftYou know, one thing I yeah, you had on here is risk, right? Yeah, um think about that a little bit. Just understanding risk, right? We we are playing in a in an industry that's playing in underground soils that we don't know the conditions, we don't know what's there, right? So the big rock is so really doing your preliminary engineering and understanding that risk and getting into your project specifications and defining who owns that risk is an important thing because if you don't do that, the owner owns that risk. It's their project, it's their money, it's their need. Um, so that's where I think some of these projects get off track is not understanding the risk and not having a plan for them if if you encounter them. So I just wanted to push that piece uh because it's it's a very viable technology and a very awesome um means to complete our projects. But just just understanding that risk component is gonna be a good benefit.
Brian SimmonsUh you know, one of the questions you'd asked before, we sort of touched on this, but how do we end up as trenchless engineers? Yeah. I didn't set out to become a trenchless engineer.
Marc CulverYeah, you know, we're when you were five years old, you that wasn't a career goal for you.
Brian SimmonsYeah, no, no, it was like I only want to work on stuff that nobody can see. You know, that'll be super cool. I'll have to we'll drive down the street and I'll tell my kids that I worked on something under this pavement and they'll roll their eyes. Yeah, um, that that happens now. That happens now, but I did not set out to to be here. Yeah, exactly. Exactly. Back in the day.
Mitch HoeftNo, but there's a pipe about 40 feet below it. Yeah. Okay, that's well, that's pretty boring.
Brian SimmonsBut so but both of us, I think, arrived at at this trenchless world as a it initially was a novelty and it was very expensive. You know, you use the word niche, I've maybe overused it in this podcast, but it was it was very niche, yeah. Uh, and now it's become an integral tool, and we see it being used everywhere. And and it has a lot to do with the value of things that are above ground, which is okay. We sometimes get to work on those too, you know. But uh, it really allows us to sort of protect the environment to make you know projects go smoother, go quicker for residents. And so that's that's really at least in my career, what I've seen trenchless go from you know, a very specialized tool into something that is being used every day, you know, it being brought in as small pieces of larger projects now because of the availability of the tech and the contractors and all that, you know, it's possible to just pop in and do one part of a project trenchlessly and then the rest of it can keep rolling and avoid, you know, whatever it is, you name it, some old church or a big old oak tree or whatever, you know, three rivers park district stand of oak savanna, who knows what it is, but um I think I think there were some really uh old Norway pines.
Marc CulverUm my city manager and I went for a walk yesterday through there, and he he's like, they're Norway Pines, and they were huge and they were beautiful. And yeah, I was like, We can't cut those down.
Brian SimmonsNo, yeah, no, we don't want to do that, we want to drill under them.
Marc CulverRight, exactly. Well, that's awesome. Thank you. I really appreciate both of your times. I'm just gonna add here, just you know, this I think this conversation, if you're listening, if you're a public works director, if you're a city engineer, even if you're just a young uh utility engineer or civil engineer, French list engineer. Yeah, um, you know, I think that you know, one of the the overriding themes of this podcast is you know, don't be afraid to ask what if. Like, you know, how can we save this? How can we um save these trees? To your point, the oak tree or the the the Norway pines or whatever. Um, how can we avoid this disruption? Um, how can we keep this roadway open or whatever? How can we cross this body of water? Um and it's not to say that it's necessarily easy or whatever, but there are some tools that are really uh well vetted, well proven, and getting more and more cost effective over time. And you got great engineers like these two that will help you uh walk through those decisions and help you design that. So thank you, Marc. Thank you. Thank you. All right, everybody. One last thing before we go. This is our fourth season. I think it's our third podcast in the fourth season, which started in June. That doesn't bode well. Um, but hey, we would still love to draw our audience. So please help us spread the word by liking, reposting, andor commenting on LinkedIn or other social media platforms that you see us on. And let us know what you think of this episode in the podcast. Um, so thanks everybody for listening. Nerds out. Nerds out.
