Tremendous growth in the Nashville area has limited the amount of developable land. Listen as Bert Morton and Drew Stokes, two of CEC’s local Nashville team members, dive into two notable projects that have changed the local landscape for the better and highlight some of the challenges developers and engineers are facing in rapid-growth regions.
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Bert: Hey greetings, this is Bert Morton. I’ll be your host as we discuss some challenges associated with development in rapidly growing areas. So if you think all the good sites are gone, you’re probably right, but the redevelopment of challenging properties is possible and can provide many benefits. I’m the civil engineering practice lead in CEC’s Nashville office, working in the site development group. I’ve been an engineering consultant for more than 20 years, and I’ve worked on hundreds of site development properties in Middle Tennessee. My family has been in this area for hundreds of years, and I grew up here, so it’s been fun watching the area grow. I’m joined by Drew Stokes, another civil engineer from our Nashville office.
Drew: I’m Drew Stokes. I am a relatively young engineer. I have I’ve been working here at CEC for four years ever since I graduated from UT at Knoxville, and I’ve been working with Bert for those four years and I’ve done a variety of projects from multi-family housing here in Franklin, with the Walker Place project, where we made a 247-unit, affordable housing complex to the Nashville Zoo, where we designed a 60-acre multi exhibit development with a boat ride. I’ve also worked on TownePlace Suites that was on Charlotte Avenue. It’s a hotel and mixed-use development. That is one of the first projects I got to work on here at CEC. It’s a 10-story hotel just outside of downtown Nashville.
Bert: TownePlace Suites, outside of downtown Nashville. How big of a property was this was this? Was this previously developed? Was it a brownfield site?
Drew: Yeah. So, this site is three separate parcels and an abandoned right of way from I guess, historic Nashville. There was a pharmacy, a cell phone store and a Subway. And so, we had developers come from Nashville and approach us to put a hotel during the big hotel boom here in Nashville. The site was one of the last sites that they had here in Nashville. It seemed like nothing was going the right way with this site, and it couldn’t get sold. But these ambitious developers came in and saw a vision for the site and reached out to us.
Bert: Nashville, if you remember back about five years ago, they had the TV show “Nashville.” That seems like when the dam broke loose in this place and everybody went kind of crazy over Nashville. People were coming like crazy, still are today, but we were building hotels everywhere. And at one time if you drive through Nashville, you can generally see about 14 cranes between 14 and 20 cranes at anytime. People are building high-rise hotels, trying to get into town for the country music, for the sports teams.
Drew: This site was just outside of downtown, very close to the interstate. The developers really liked having that site from the interstate. However, the site also had a historic piece to it. There’s sewers that run under this site, and there’s an 11-foot Kerrigan tunnel that comes from the west on this site. There’s a 9-foot diameter Lick Branch sewer that comes from the southwest. And then a 30-foot diameter sanitary sewer that comes from the housing developments of the north.
Bert: That was a 30-inch, but do you remember when we first got that metro sewer map from Metro Water Services, they listed the sewer, if the color was green line that meant it was a sewer, if it was a blue line that meant that it was water. They put the size in there. There’s a water line, it had a 6 on it, so it’s a 6-inch water line. There’s a sewer line that says 30, that’s a 30-inch water line. Then then there’s one of those going right through the middle of the site that had an 11 on it now. So, OK, that must be an 11-inch sewer line. That’s a funny size sewer line, that’s off size. We found out that that 11 was actually 11 feet.
Drew: Yeah, they constructed a sewer over the existing stream back in, I guess the late 19th century. And they used brick, and we did a little research and found some really old pictures of them constructing the sewers. We didn’t know what kind of shape that brick was in. We didn’t know how thick the brick was. But we knew that it was under our site and we didn’t know how we were going to build a hotel on top of it.
Bert: Metro kind of had the same questions, so they made us have a lot of meetings with them. How many meetings did we have with Metro, probably 20, 30 before we even did any design plans. They were very concerned because this drainage carries half of West Nashville, going out for 10 miles or so to the West. It’s a lot of drainage coming to this site. So what did Metro do to kind of help protect their sewer? What kind of requirements did they put on us?
Drew: Metro was very protective of this sewer, and most of that caution came from they didn’t really know what kind of shape it was in. They didn’t know structurally how sound it was. So they decided to put these cautions into place, and they wanted emergency measures in case anything were to go wrong during construction. And those measures were that we had to be able to bypass pump within 24 hours, the entire capacity of that sewer. We also had the limitations of being only allowed to have tracked equipment on the entire site and we weren’t allowed to have any equipment driving over the exact sewer. So we had to go out there at the beginning of construction and place stakes marking where the limits of the sewer were and where no equipment was allowed to go.
Bert: So pretty much for this .67-acre site, we weren’t allowed to do anything on top of third of it? A fourth of it? It really hamstrung us on this one. How about the agreement they put on us? Metro put, because it was vital to the drainage of the entire area, they put a restriction on there that if anything were to ever happen to the sewer, the developer is responsible to pay for it, 24 hours a day, 365 days a year. So the geometry the site of the way, they had to design the site is they had to allow for 21-foot vertical clearance over the sewer so they could access it at any time. So the entire building was designed around it to bridge that tunnel.
Drew: So they installed grade beams and since there was a parking garage that needed to be put on the first few levels of the the hotel, we had to design a ramp that got up the 21 feet high vertical clearance in that short space that we had. So it was a pretty steep ramp being around 16%. We also had to dedicate a 30-foot access easement horizontally through our site, so that any time they could come in and dig up that first floor of the hotel if they needed to, if anything were to go wrong with that sewer.
Bert: So how do we find out about the condition of it? Knowledge is power, right? And if we don’t know what all the impediments are of the development then we’re in for some surprises during construction. Tell about how you go about finding out what the inside of a sanitary sewer looks like that’s 11-foot diameter, always full of water. Can’t use a robot. Can’t use a boat. A brave soul had to go in there tethered. If you look at Google Maps, I think of the site today on the street view, I believe you can see the trucks that are out there and that guy was making this faithful descent into the bowels of Nashville, but it is an amazing ride. The video is probably worth, it would probably make a pretty neat ride out of it if it wasn’t deemed to be gross, but it’s a river. You have a river underground and that was the only way you could see what this looks like is that guy had a had a video camera and he was assessing what the integrity of the sewer was. A lot of surprises on there, too, right Drew?
Drew: Yeah, you could see the old brick from the original construction, and you could also see where you had cable companies, communications companies that had no idea that that tunnel was there and they had just bored their lines straight through horizontally across the tunnel. And you could see just all sorts of communication lines and just anything and everything was down crossing the sewer. Like, they had no idea that it was there.
Bert: No Ninja Turtles, though, right?
Drew: No, not this time.
Bert: What about on top of the ground? All the properties that were there, three properties. Metro allows you to develop, if it’s owned by the same property, they will allow you to quit claim deed those properties together. So you don’t have to do a plat of consolidation. However, we advise the owner to do a plat of consolidation. Can you talk about the benefits of doing that, Drew?
Drew: Yeah, the consolidation of the property really helped with especially when you have the abandoned right of way in the middle of that property and it also helped when we had to give right of way to the city on the front of our building. So it was a very I guess messy parcel and we did this to reduce any issues we had later on. When you build a hotel you want it to all be on one property.
Bert: If someone could come in later and did a review of the of the deeds, you don’t want any surprises, especially when you have a 10-story building actually mixed-use development. They put a shop and a restaurant downstairs, need to make sure that that is that’s clean and those guys are protected from any claims of properties. So our surveyors did an ALTA survey, did the title research and found out that this property is now free and clear. This is owned by Charlotte Avenue LLC and we’re good to go. I think that was a smart move. Once they got above ground, they were pretty much good to go, weren’t they?
Drew: Yeah, once they started they got rolling and it seems like they constructed it really, really quickly for a 10-story development. And it didn’t seem like there were too many challenges during construction, and I think that the all the due diligence we did beforehand really helped out during the construction process.
Bert: I think maybe one of the only benefits that I can think of about COVID is that streets were empty. So a downtown site in Nashville, there was nobody on the road so they actually built it pretty easy.
Drew: Yeah, Charlotte Avenue is normally a really busy street in a big corridor for downtown Nashville, and I think it helped with all the the sidewalk improvements and communications and utility installations, when they did have to shut down one lane of that road, it wasn’t impacting the commute to Nashville to much during COVID.
Bert: So, what’s next there, right? That’s kind of the first, before there isn’t, you know, the old drugstore, you had the cell phone store and the Subway restaurant. And now you get this beautiful 10-story hotel, which you can see from the interstate. What’s next? You think there’s more coming?
Drew: Well, I really think this project kind of just opens the door. The developers took a chance on a site that really was deemed undevelopable and they made it work. And so if that site can be developed, I can’t think of another site that couldn’t be developed.
Bert: They didn’t quit. They didn’t quit on it. They were adamant. They had a vision and they stuck to their guns. It’s a beautiful project. It’s something I’m really proud of.
Drew: Yeah, I think that this kind of opens the door for other developers to, if they think that they have a site that won’t really work, they can actually make it work. Bert, do you want to talk about Harpeth Square?
Bert: I’d love to. So Harpeth Square is another challenging project that was a long time coming. So I grew up right down the road from Harpeth Square. It’s in historic downtown Franklin. So Franklin is one of the suburbs of Nashville located about 10 miles south of Nashville, but the site of one of the bloodiest, kind of the penultimate battle of the Civil War when the Confederate troops were coming up from from Alabama and made it through Franklin, which was held by the unions, the union troops during the early part of Civil War and then made it to Nashville and got their butts handed to them and they ran back and the war ended soon thereafter. Franklin has been known for two things for years. One of them is for Civil War battle and also known for famous musicians. A lot of the country music stars and pop stars now live in Franklin. It’s not unusual to see Justin Timberlake or Cheryl Crow or Chris Stapleton or back in the day, Wynonna Judd, they all live in the area. So you’ll see them around and I think Nicole Kidman lives down there. So it’s a beautiful place and if you ever in Franklin, or you ever in Nashville, take a take a day and go down to Franklin, walk downtown and see it. It’s a beautiful downtown scene. A lot of shops and restaurants and things like that. It’s a fun place to go. But one thing you didn’t have in Franklin for many years is you didn’t have a hotel and that and that was a shortcoming that was kind of painfully obvious. I mean people would come to town and they would have a good time and then you spend there the tourist dollars somewhere else. Some savvy investors saw that problem, saw that need and a lot of them got together and purchased probably 10 properties all within one of the original blocks of downtown Franklin. So between First Avenue and Second Avenue, Main Street and Bridge Street, but one of the original blocks of downtown Franklin, nobody knew what to do with it. There have been old houses there for years. There had been some shops there, like metal shops and things like that. Just brimming with potential because nobody knew what to do with it. Nobody had the money, the time, the willingness to put this together until about 10 years ago. A group of investors got together and started this vision called Harpeth Square. Harpeth Square is going to include a hotel for sure. Also includes some a retail space, includes a multi-family area, so apartments, condominiums, and a much-needed parking garage. If you ever go to downtown Franklin during Main Street Festival or during the pilgrimage festival, it is impossible to find a parking space. So they put a 500-car parking garage right in the center of it. In order to get this this built, it was a planned unit development through the city. The first thing you need, just like TownePlace Suites, you need good information. So hired a good surveyor to put together the pieces, the boundary information. These boundaries had been — it’s one of the original when the original plats from from the city, from the 1790s. That’s where the boundaries first started. There’s a river going through it and multiple people owned it for many years and they’re putting them all together. It was a real puzzle. So once we got the boundary put together, it comes time to design it and in this case, it really helped us to be in town. Being a local firm in Franklin, knowing the people, knowing the city staff well was vital. Knowing our teammates, the landscape architects, we worked with the surveyors we worked with, the architects we worked with, communication was so important. One of the main challenges was the Harpeth River. So the Harpeth River borders this project on one side of it and the area had been prone to flooding. A portion of the property was within the floodway, and FEMA was coming out with new flood maps. And so we had to also coordinate with FEMA to find out what the new finish floor elevations were going to be. So we can’t build a building any lower than one foot above the new base flood elevation. So we had to also be up on our FEMA knowledge to know what elevation to build it. We also had to build a retaining wall along one of the boundaries at the site to help mark the new flood way, which is being modeled and was implemented in the new maps.
Drew: Bert, was there any significant issues with getting the city on board with this project, being in the downtown — it’s the first thing you see, when you come downtown Franklin from the north?
Bert: The city was on board with it. Not only because we were giving them new sidewalks and streetscape along four blocks. Like you said when you come down from Nashville and Franklin Road, this is the first thing you see once you cross the Harpeth River. It’s a beautiful development.
Drew: It seems like a good thing to note here is the relationships between the municipalities, the other consultants on the job. That’s a real important piece to this. And if you have a good team on all sides of the fence, then I think these projects, it helps make them a lot smoother.
Bert: For sure. This project was a little atypical in that we had two separate architects. Well, I guess Charlotte Avenue had a different architect at first. That’s the thing about the importance of having a local consultant especially for survey, for sure, for civil and due diligence work, having somebody local doing the groundwork literally and figuratively I think is so important because when they changed architects on Charlotte, we had to quarterback. the process where we needed to hand off the survey, hand off what we had and show them where we were so they could have a seamless transition. And it was a seamless transition for Charlotte. Same thing for Harpeth Square. The architects came in, wheels to the ground, booking it from Day 1.
Drew: Yeah, and I guess that that extends to when you’re under construction and you have to have a great contractor, as well. I think that it’s so important to have all this great communication between architects, between engineers, between the contractor, between the developer themselves. I think that’s so important to get these really hard sites and these redevelopments to get off the ground and get finished.
Bert: Aren’t you finding that the civil, at least from a permitting standpoint, the order of operations is pretty similar no matter where you are? A planning department’s going to need to approve it. You’re going to need to have some sort of an idea of the shape of your building and where it’s going to be so they can say all right, this matches what we want it to look like from ground up. There’s gonna be some kind of permitting with stormwater, for sure, saying OK, well you can’t increase the amount of runoff off your property and you can’t degrade the water at all. Those are the same. Every one of these municipalities has a different way as far as how big is your setback from a planning standpoint and zoning standpoint? From a stormwater standpoint, are you going to have to infiltrate your water? Are you going to have to detain it and to what amount? From that standpoint, pretty beneficial to have somebody that’s been there before and can talk the lingo.
Drew: I agree.
Bert: I’d like talk some more about some of the challenges of these developments. In Harpeth Square, take stormwater, for example. We are on a landlocked site. It’s already pretty impervious. We’re actually decreasing the amount of imperviousness. There is still the water quality question that needed to be addressed. And there wasn’t really a way in this development to infiltrate the amount of water that you need to do on this property, but the city had a need and had some space to treat this on a watershed basis. So down I guess a quarter mile from the site downstream on the Harpeth River, there’s a new park, Bicentennial Park, and we designed an off-site bioretention basin that serves an equivalent amount of runoff from the Harpeth Square site. That to me showed as much as anything how much the city was willing to work with us on this. The city has a responsibility as a municipal separate storm sewer system. They have certain measures they have to meet and in the case of Harpeth Square it was really, really difficult to do that. But everybody agreed that this was a great project. So they were willing to work with us, by allowing us to construct, basically, it’s a regional water quality basin, which will serve other people to, it’s for the greater good. The Harpeth Square people had to pony up some money to do it. But in the end it benefited a lot of people. You mentioned before about having to TV the lines. What were the other stipulations that Metro put on that, do you remember, Drew?
Drew: Yeah, so during construction they wanted all the construction traffic limited, like I said earlier. They also wanted vibration monitoring for the site to make sure that there’s no cracks or anything that can hurt the sewer. And then after construction, we had to video the tunnel again from the inside. So those were certain stipulations that you don’t see on normal sites that Metro Nashville required for the Charlotte Avenue site.
Bert: We looked at a few different options on the front end because of the way that sewer was oriented across that property. We put together an option to try to reconstruct a bypass around our site, but the problem is we couldn’t do it on our property. Metro’s engineering department was adept enough to know that, and they’d seen buildings built over sewers. That’s that’s happened before. Although, I don’t think it had happened at as shallow of a depth as this one was. What about the odor, Drew? What do you think? Combined sewers, do they smell as bad? Is it all that? Is it as bad as what people say?
Drew: Well, certain cities do have that combined sewer smell and there are places in Nashville that have that. With us designing a hotel on top of a combined sewer, odor control was a big concern that we had. We didn’t want our building filling up with the odors from that sewer. So we had to do some research first and then talk to Metro Water Services about how we can prevent odor escaping the sewer. I know we started out, we looked at doing a P-trap type scenario, which is something you’d see in your house except on a larger scale and I think ultimately we ended up with a check valve that was in line that went into on the very end of the sewer right before we went into the manhole that we were tying to for the storm water. So none of those gases can escape back out of the tunnel and into the building.
Bert: That was one of those things that a light bulb went off when the contractor proposed that. That was a value engineering. And ended up saving the developer a lot of money. They weren’t necessarily in this case, they weren’t trying to save money so much. The area was so congested, and we’ll talk about this too, Drew, that the sewer as big as that thing was, we really didn’t know exactly where it was because it was built on a creek and creeks don’t need easements to flow, right? So there’s no described easement from when they built this sewer and 1870, where this thing was. So there’s no description of it. There is no survey of it when they needed to put in this P-trap structure that we designed, there were simply no room for it. The sewer was actually a little bit closer to the property line than we thought and so we had to shift things around and we really couldn’t fit it anymore. Talk about the challenges of the depth of the sewer over there in the, we’ll called the top right corner of the building.
Drew: The sewer was very shallow. Most downtown sewers are significantly covered by Earth and in our site the sewer was about 3 feet deep from the existing grade. So we had to bridge over that sewer. So we had to build up our site a little bit and that was constrained, as well, to access the driveway from the street into the building. So we couldn’t have too steep of a slope there. But we also had the sanitary sewer. We had grade beams going across the top of the sanitary sewer to make sure there was no load on top of that old brick sewer. We really didn’t know how deep it was until we went out there and dug down delicately to find where the brick was. And even then, we weren’t sure how thick the brick was and how many courses of brick were on that structure. We didn’t know if it was three courses thick, four, five, six, courses thick. We really didn’t know. We knew it was an 11-foot sewer inside diameter. We weren’t sure how much that extended to each side and that was very important when we were placing our pylons for the building to sit on.
Bert: So another one of the Metros requirements was that we’re not allowed to increase the load over this old brick sewer. So when we were going through the design process, all right, we thought the sewer is about 7 feet below ground. So we said, OK, the sewer is 7 feet below ground, we’ve got some asphalt here and then we got some dirt here. And if you multiply the area times, the unit weight of soil and asphalt, this assumed depth, then we have this amount of weight. And so we know when we finish this design we’re assuming to have a little bit less weight than this, and so we’re going to be home free. We got 7 feet before, now we’re going to have about 3 feet. We can put concrete on here. We can put a ramp. We’re home free. But to what Drew mentioned before, when they actually dug it up. they realized that we don’t have 7 feet, we have three feet and the weight of 3 feet of concrete is higher than the weight of 3 feet of soil and asphalt. So what did they come up with, Drew?
Drew: So under the under the ramp we had to put a foam support. The density was such that we weren’t increasing anything when you add the density of the foam and the density of the concrete. It mimicked that of the existing soil that was on top of the sewer.
Bert: Structural foam.
Drew: Yeah, it was something that Bert and I were unaware of and really weren’t familiar with but it turned out to be the solution that Metro wanted to see, and it works.
Bert: It doesn’t bounce or anything when you go up that speed ramp, it is in there solid. It was one of those one of those construction materials you don’t expect to see when you’re working on a 10-story, building is large blocks of foam, but it’s been done before. This wasn’t something that they invented on the fly. This is an actual accepted practice, and it’s worked. It worked great.
Drew: I think that really just goes to show you that these sites, while they’re tough to develop, anything is possible. If you want to develop a site, the city is there for you. They want to help development and they want to bring in those tax dollars. So Bert what have you learned, and what can can you do to better your chances of being successful in a project in these redevelopment with problematic sites?
Bert: What I’ve learned is I should have gone to medical school. I’m kidding. This is such a rewarding thing to do. Site development is such a challenge. You’re doing something different every time. It’s a fun thing to do, especially in a busy place like this. The bigger the challenge in a way, the more fun it is. So number one, I would say you should always get a good surveyor. Someone who knows the area, someone who has a little bit of experience, but don’t scrimp on information. A lot of the funding agencies will require you to get an ALTA survey. That’s a survey that’s produced with given guidelines, so you kind of know what you’re getting. One of those things you’re getting in there, you’re going to get a title research. So you’re going to find out who has perceived rights to this property. So as soon as you know where your area is, how big your boundary is, the shape of it, then you need to find out what’s going on within it, what the physical properties are. Then the utilities underground, where the storm pipes are, where the water pipes are, where the sewer pipes are, the gas, the electric lines. You don’t forget about the guy wires. How many times have we seen a site we’ve been developing it, and we see where the pole is and then you put your driveway around the pole, but you didn’t realize that there’s a guy wire there. If you’re going to build on multiple parcels, like on Charlotte Avenue, like a Harpeth Square. You recommend combining the plats even if the city doesn’t require it. Combine the plats, make one clean boundary, get rid of all your internal setback lines and things like that and start from a clean slate. It takes a little bit of time, costs a little bit more money, but in the end, I think people will be glad that they did it. Pay for private utility locators. Tennessee 811 or whatever state you’re in has a one call system. You have to call them by law, but they only have to the information for the public utilities. So once you get onto your property, they don’t have to locate them. And oftentimes they don’t. Utility location services, they’ll come out with a ground penetrating radar and they’ll locate with relative accuracy what’s there. Oftentimes they can tell what type of pipe it is, too. So make sure you get you get that information.
Drew: Yeah, I think one of the things I’ve learned is how important it is to hire a local consultant from the beginning of the project. For the due diligence phase, for the civil design phase, or anybody that’s well-versed in the area, with the local codes and the processes. And especially if they have relationships with those regulators. That really makes the project, ensures that it’s constructed, it’s smooth and it’s a within local regulations and you don’t have to go back and change things at the end or any time after it’s been already set in stone. After you’ve already done your cost estimates. The changes afterwards that could have been prevented are those that just drive developers crazy. Bert, do you have anything else you’ve learned?
Bert: That kind of segues into another one. You need to have a good, obviously, need to have a good relationship with your client. The developers are going to give the surveyors and the civil engineers, they’re going to pay them a good amount of money to help with the development of this site. So communication is very important. And one of the things you need to make sure that your developer knows, you need them to trust you, that you are out trying to meet their goal with them. But make sure they understand that development is an iterative process. There’s never been a single development that I’ve ever heard of that’s been drawn exactly right the first time, and that’s how it was. Development is an iterative processes, especially on a site that’s challenging like these are. We didn’t have an idea, even with all the survey information we had, we didn’t know exactly where the Kerrigan Tunnel was. We didn’t know exactly where some of these utility depth were. There are some abandoned utilities that were there. We didn’t know that they were abandoned. Those things happen. If you have a good relationship with your developer, they understand you’re going you’re going to make some some changes in the fourth quarter. They may not like it. But as an example, it’s a whole lot easier to draw 100 feet of pipe than it is to construct 100 feet of pipe. It’s a whole lot more expensive to build 100 feet of pipe. If the developers you allow the engineer to sharpen their pencil and work another another hour or two to save tens of thousands of dollars, putting it that way is generally something they’re going to be all for.
Drew: When your developer’s trusting you, your developer also needs to trust their contractor and contractors make all the difference when you’re constructing these tight buildings that are 10 stories tall in downtown areas, especially over 11-foot diameter tunnels. I know Harpeth Square and TownePlace Suits both had fantastic contractors and they were led by skilled project managers and great site superintendents that had an eye for detail and they could see problems before they actually got to them. So it’s important for developers to get teams with capability and local experience to make their projects go as smooth as possible.
Bert: Don’t just automatically award the low bid, right?
Bert: I guess that’s about it. I have nothing else to add to this matter. These have been fun projects. Nashville is a great place to work. I think we’ve got many more years left of them, and more challenging sites.
Drew: Yeah, it seems like the sites are only going to get more and more challenging as the years go on.
Bert: We’re ready for it.
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