This presentation is part of the Are We There Yet: Preservation of Roadside Architecture and Attractions, April 10-12, 2018, Tulsa, Oklahoma
Kelly Caldwell: Thank you to the NCPTT for inviting a Northern neighbor, even though I am from the US. But, talking about a Canadian context in terms of roadside architecture and attractions. So, for my presentation … Great. Talking about the Concrete Jungle, conserving Canada’s menagerie of concrete sculptures. These are some recent projects, in 2017, and a current project, for this year, that CSI and Ottawa’s office have been involved in. Of working with municipal and universities for the preservation of these of beloved pieces that have become the intrinsic value of local communities.
The three main projects that I’m going to be talking about are the Centre Street Bridge Lions, which are located in Calgary, Alberta, the Maurice Savoie Mural, which is located at Memorial University in St. John’s, Newfoundland, and Dinny the Dinosaur, also located in Calgary, Alberta at the Calgary Zoo.
You can see here, that’s a heritage postcard from the 1950s of Downtown Calgary. The Centre Street Bridge is one of the main roads. It’s a grid system, so it’s the main road. Rather than a main street, they have Centre Street. And the lions are actually four lions that were placed on kiosks through the pedestrian walkways leading into and out of the city.
As we found out yesterday, everyone loves dinosaurs. An example of Dinny the Dinosaur from the Calgary Zoo. Who was, and still is, a beloved feature of the zoo. Not just the live animals. And was readily used as advertising and a destination spot. This is actually … My coworker and coauthor Sophia, this is actually her grandparents at their honeymoon, who traveled to go see Dinny as part of their trip.
Just a little context. I will admit, I’ve been in Canada about five years now, and my geography of Canada was lacking. The main projects, one of the biggest factors obviously in Canada is weather. It’s the Great White North, and it is true. Most people joke, and I’m sure anyone from northern states. There’s two seasons in Canada, it’s winter and construction. So that also limits the preservation opportunities for a lot of these outdoor artworks because your working times are very limited, especially if you’re doing large scale projects like these, as well as the type of materials that you can use because freeze-thaw, and just sheer freezing is such a problem.
St. John’s, all the way far far east in the Maritimes. And, Calgary out west in a Western Prairies. The weather itself, both are highly windy. But the Calgary has a unique feature referred to as the Chinook. Right next to the Rockies, it actually, in the winter, you get high shifts. So you get this weird … It will be negative 30 degrees for two weeks, and then it will be plus 50 for two weeks after. So you get these quite drastic shifts that facilitate further problems with any outdoor structures. Compared to the Newfoundland Maritime climate, where it is highly windy, highly sunny, snow constantly, and this can all happen in changes of fifteen minutes within one day throughout the year.
Because these pieces, which many of the ones that have been spoken about with conference, are identified as either public art or roadside art, whether it’s privately owned or publicly owned, there’s always this kind of balance between the conservator or the researcher, the public, because they’re the ones you’re preserving this hopefully for, and also the client. As we work in a private industry, there’s always this balance between what are your contractual obligations versus what advocacy should you be promoting to the public for the pieces that you’re working on.
Then also, the public opinion to the client. We found a lot of the instances, especially in Calgary, there was recently an election cycle. And an official misspoke about one of the public art pieces causing a very large controversy. Just because they stated something inaccurate. Referencing one of the native communities. And as a result, there was a complete moratorium on any public artwork.
We were able to continue because we had an existing contract, luckily with the lions, but we weren’t allowed to speak about it, we weren’t allowed to do any PR, any discussion with the public, anything because it was pretty much a big no-no because then the public said, “Well, why are we spending money on things if we can’t agree with it?” So it’s this constant balance. But always, hopefully, the object at the center of it.
Expanding on that, a lot of the preservation goals with these outdoor sculptures and roadside attractions is always you have your ideals of what you’re working towards of wanting to do everything from historical research, and getting all of your paint analysis done, doing material identification, and historic research and photographs. And many times, like I said, your timelines are very short. The contracts don’t cover that kind of information. So, these projects really focused on just getting the work done. Because, for the most part, these were, while publicly loved, very neglected pieces. And it wasn’t until they became health and safety hazards that the city and universities decided to do something about it.
This is one of the Calgary Lions. As I said, it’s one of four. The bridge itself was built in 1916. And, designed by one of the architects that was a member of the city council. And the lions are designed after the lions at Trafalgar Square in London. This is the time when Canada is still a British entity, so this is always the connection there. And, the lions themselves are thirteen tons. Quite enormous. And were created in five separate sections, cast around a cage of internal rebar, and then set in sections, as you can see here, on top of the bridge. And then these little kiosks you can walk through and under.
After that point when they were installed, then they had local sculptors come in and apply a shelter coat to add in additional details for the mane and the faces. To kind of give a little bit more dimension to the lions. And the idea was then to protect the base concrete that was sort of the same kind of concrete that was used as part of the bridge. So these had to be structurally integral, as they were several feet up in the air and hanging over passersby.
Unfortunately, there was very little that was done for these objects over their numerous years in Calgary in the extreme weather. So, in the late 80s, it was decided one, they were widening the bridge, and two, they realized that there was work that needed to be done. So some campaigns … Unfortunately there are no records of what was done. Acrylic coatings were applied to the concrete, likely because they were spalling, and just general deterioration over time.
These coatings have had an adverse effect to the lions. After ten years, they did another round of construction on the bridge and the decision was made to actually remove them in 1999 because there were pieces falling off, they were found not to be structurally stable. But because of the link with the community, and they had such a presence, they replaced the lions with new casts. But the city saw this as an opportunity to preserve the existing ones and they became absorbed in part of the public art program that is widespread throughout Calgary.
You can see here, basically four of the lions were all taken off. Sent to a sort of lion graveyard on the top of a hill. And, three of them had been sitting there since 1999. They did decide to preserve one of them and put it in front of city hall as an emblem of the of connection street itself and the city hall, which is one block over. What they ended up doing with the treatments, as you can see here, the amount of cracking that is throughout the structures, especially along the seam lines. While there is an internal rebar, there is no structural ties between all the different pieces. So, as the rebar, which they found to be almost one hundred percent corroded and nonexistent, through ground-penetrating radar and radiography sampling, there was not much holding it together outside of just the cohesion of the concrete mix.
When they removed them, they had to take part of the bridge.. You can see in the photos on the right, the stepped section with the core holes is where they drilled through it to remove it from the bridge. Then they installed HSS steel framing to support it and allow for transport.
In 2017, the centennial of the creation of the bridge, the city decided that they were going to preserve the second lion, but take a different approach. It was going to be displayed in a public park overlooking the bridge. To have a connection between the original and the old, and the replacements and the originals, as well.
However, the decision by the city officials was they wanted it to be conserved as a ruin. Whereas the one in city hall was more a restoration approach. They wanted to illustrate the life of the lions. So they wanted the cracks to be seen, they wanted all the bumps and bruises, warts and all approach. As part of our assessments, we took that into consideration in choosing our treatment methods.
Our second case study was the Maurice Savoie Mural, which is a large scale mural on the side of Memorial University. It’s twelve large scale decorative panels that is a combination of cementitious mortar on a concrete backing that is structurally hung on the side of the building. It dates to 1966. And Maurice Savoie was a famous Québécois ceramicist. While there’s a lot of research about his ceramic work, if anyone’s been to Montreal, he did a lot of the murals in the Montreal tube station … Or, subway stations.
Unfortunately, for whatever reason, there is no record of him ever using a cementitious or concrete medium. There are no records of why on earth this thing ended up in Newfoundland. The university has very little records. But, basically, it was put up there in 1966 and it’s not been touched since.
As you can see, there is a lot of large scale loss as a result of the corroding rebar. Popping pieces off and, recently, some pieces had fallen into the walkways underneath at the university. it was deemed a health and safety hazard. One of the other issues that the client had to decide was the building needed a full restoration. It’s got a lot of leaking windows, it’s got a leaking roof. But what do you preserve? The standing building or the artwork? And it came down to the health and safety needs, that they actually preserved the artwork over the building.
A lot of the conditions, very typical of concrete and cementitious materials. Exposed and expanding rebar. With this mural specifically you can see on the far right, the two separate layers, the outer section of the cementitious mortar, which would have been made in a mold, they would have pressed it into the mold. He added additional aggregates and colors, to get these shapes and figures. And then, the concrete backing, which has a large mix aggregate, would have been poured on top of that with a layer of embedded reinforcing steel in between. However, probably when making it, the rebar sunk. In some instances, the rebar is actually protruding through the surface, or within a quarter to a sixteenth of an inch from the face. That’s caused some serious problems. And also, all of the caulking had failed. It likely had been replaced at some point, but, like I said, there were no records existing.
One of the big things that we looked at is doing full condition assessments to understand the extent of the damage and find all of the loss and all of the voids. Whether it was a visual loss, or there were voids behind the surface. We were able to address these problems. But one of the biggest factors was addressing the biological growth. The climate in Newfoundland, as I said, it’s very damp. And temperatures vary throughout the year. It was of a perfect climate, and perfect surface for this type of problem.
As a result, there was very extensive biological growth over the entire mural, obscuring a lot of the details, which is a wetland scene of crane-like birds, reeds, plants. Typical of sort of like the marshlands, we’re assuming, that he might have drawn from of the nearby environment.
The other aspects that he used, he did embedded pebbles, crushed pebbles and actually slate and terracotta into the mural. It actually extends out from it to give it more depth and dimension. And then used a secondary, highly pigmented, mortar, sort of like splatter painting with bright greens and bright red throughout the mural. But unfortunately, the biological growth had sort of leeched on to that. So trying to find the solution of, “Do you get rid of the pigment?” Or, “Do you get rid of the bio growth?” Through our work, we did a lot of color matching and mortar samples so we could find a comparable match for the work. Sourcing local sand, sourcing local stones for the replacements prior to us starting all of our work.
The most exciting of it is the dinosaur. So, Dinny the dinosaur, similar to the ones that were talked about yesterday, it is from the 1930s. It’s a large scale concrete dinosaur located at the Calgary Zoo. It was actually one of 56 created by a local artist for this sort of prehistoric park. Similar to the Midwest in the US, dinosaur and oil is what Alberta is known for. So this was a very big local attraction for Calgary.
Unfortunately, in the 80s, and through the time period, most of the collection of 56 dinosaurs were either removed or demolished. And the only original still standing at the zoo is Dinny. However, there is a new prehistoric park separate from Dinny. That is fiberglass dinosaurs that has sort of virtual walkthroughs for children, and groups. So there’s a little bit of a disassociation that Dinny, unfortunately, is now sitting alone by himself tucked away.
And then also with … There’s been a lot of rejuvenation with the zoo. Mainly because pandas are coming from China. Which spurns the need to do something with Dinny. There has been a lot of … Similar to the concrete, there’s been cracking, there’s been peeling of the paint that has resulted in health and safety concerns. So they’ve had to block off the area. The other aspect is he’s now blocked off by a new road that was added in to the zoo for better parking and access. So it used to be that you could … Sort of this landscape that he would sort of appear out of nowhere as you turn a corner. But now, he’s sort of blocked off, the road actually prohibiting access. Sort of opposite of everything else.
We know he’s been painted multiple times over the years. But outside of regular maintenance of general washing from the zoo staff, little has been done. He’s also located directly next to an animal pen. So there’s that extra layer of now there’s bits falling off. So it’s not only just a hazard to people, it’s a hazard to the animals. And there’s the likelihood, which we’ll be doing analysis to confirm, if there is lead paint. Also, if there’s asbestos. Asbestos was used widely in anything and everything in Canada. It was quarried there, and a lot of times it was actually mixed with cement to make it more ductile and provide a little bit more stability. So, we’ll be confirming that. And then evaluating how do we actually treat it if you have that amount of hazardous materials on a piece that’s that big next to animals.
We also carried out the treatments on the lion following our sort of review with the city to evaluate how do you preserve this as a ruin, but knowing that it’s going back to an outdoor environment. That it’s going to be climbed on. It’s going to be likely vandalized. It’s going to be in a public park that’s not regularly monitored, typical of any type of outdoor public art, roadside attractions, there’s only so much you can control. So, what we ended up doing is focusing on the structural repairs as well as repairs to cracks, voids, losses to prevent further water infiltration into the monument.
We looked at the different sections knowing that some repair work had been done when it was removed. Gigantic steel staples were added into the neck to secure the head. But no work was done to the sort of skirt plinth that was underneath it, which was actually in multiple different sections. So it’s likely that the lion itself, while it was cast in five pieces, this sort of plinth around it was then added based on the dimensions of the kiosk that it sat on. So as a result, all the lions are just a little off. It’s not actually square and plumb, which you would think something that’s engineered for a bridge would be. But, it wasn’t.
We actually did structure reinforcement with Cintec anchors to tie those pieces together. And, the highly fragile and corroded rebar that was in the portion of the bridge was actually all saw cut and removed. And it’s going to be re-incorporated into the new design of the new display sort of platform that is being designed for it. Then we also did extensive crack repairs. Some of which were actually through cracks. Work that had been done … The client had hired an artist to repair the artworks who had done the restoration for the other lion. And while it’s great that they hired someone to do the work, unfortunately, that person didn’t have a full understanding of the best options. A lot of the crack repairs were only filling the surface. And, once those were removed, we realized that some of these cracks were actually half a foot deep.
We applied water repellent coatings and mineral pigmented coatings by KEIM to allow breath ability of the surface as well as providing a protective coating and a slightly uniform color. As I said, the client wanted it conserved as a ruin, so they didn’t want an opaque surface, or a painted looking surface. They wanted it to look a hundred years old. So we worked with him to find a happy medium of enough protection versus what aesthetic they were going for. For the cleaning, for removal of the acrylic coating, we ended up doing CO2 cleaning. Because the abrasive methods we knew would be a little too much based on what they had done with the previous lion.
As I noted with the Maurice Savoie Mural, the bio growth was the largest thing of just cleaning it was the biggest thing. You can see on the left, the bio growth, and then on the right, after cleaning. We also did similar repairs of cracks and repairs to walls. As I noted, the exposed rebar was causing areas to spall off, requiring removal. Where exposed rebar was visible, it was either cleaned or cut off and coated. And then new repairs color matched and repaired. As you can see on the bottom right, there were several light fixtures that had been drilled into the piece over the years, resulting in numerous holes, plastic plugs, kind of a little bit of utilitarian approach to electrical work.
As a result, we had to faux finish it, in essence, to get to the seam lines and everything to disappear as much as possible. And then did a similar approach of applying a water repellent and corrosion inhibitors to prevent future deterioration. Really focusing with the client that maintenance for these pieces was going to be a huge aspect.
Our work with Dinny has not started yet. But, hopefully, the biggest factor as I said, is going to be the health and safety. Evaluating how do we safely remove, if there is lead paint. And remove all the failed materials while safely, not just for the workers, but for the animals and the public. As there will be a gigantically huge influx of people to the area.
You can see here the structural engineers came in and did reviews to make sure that he wasn’t going to completely collapse on the public’s head. And found that structural reinforcements are required in his neck. There’s no internal supports, it is just the actual just frame that’s there. There was, luckily, with the cutting the hole and examination in 2008, removed a longstanding theory that there was a Model T inside of him. Where that came from, it’s unknown, seeing that he was made in the 1930s. But unsure. But there’s not one in there. It wouldn’t fit anyway.
As I noted, like one of the biggest things. While the treatment programs were a definite requirement to fix the health and safety concerns as well as get these to a stable state that they can be returned to their former glory and displayed and enjoyed by the public, is really ensuring that maintenance and monitoring programs are part of the treatment program. And ensuring that not only that there’s awareness for that with the public, but explaining to the client and the public that you’ve got to set aside money for that. This is if you want to keep this stuff, you have to keep working on it. Which I’m sure all of you deal with on a daily basis.
One of the things, the lion is actually, while it was unfortunately supposed to be removed last year, due to the controversy, work was delayed, and it is now being installed this summer. Fingers crossed. To its new location. An example of the new concrete structure that it’s going to be put on and watching over the new lions.
Same with the mural. One of the big factors was because the failed caulking had allowed a lot of water to get in between the different panels, and just sucking it into that mural, and just the rebar was just highly corroding. We try to enforce that even though access to a lot of these large scale pieces is very difficult, and time consuming, and expensive, that this regular monitoring will reduce large scale problems down the road. In the hopes that fix a little bit now, so you don’t have to fix everything or risk full dismantle and demolition later down the road.
We’ll see how it goes with Dinny. As I said, they have been washing some of the other dinosaurs in the park. So we hope that they will be able to do some type of maintenance with Dinny down the road. But, because there is that intrinsic community aspect with Dinny of this love for him, as all children love dinosaurs, do you let people climb on it? Do you not? I mean hopefully, once lead paint has removed, it can be. Don’t eat the paint. But it’s also the idea that now that he’s completely separated from his original context, and all the other dinosaurs are elsewhere in the park, how do you fit that in the narrative. Is he still advertisement for the zoo? Or is he just, “Oh, that thing that sits over there.” So that’s what we’re hoping with the … working with the zoo, doing advocacy, and possibly public resources in terms of crowdfunding to have a little bit more of a renewed campaign and new love for the new generation for Dinny.
Thank you very much.
Speaker 1: Do we have our first question for Kelly?
Speaker 2: I actually have two questions for you. The first one is, did you use any type of biocidal cleaner when you removed biological growth?
Kelly Caldwell: We did. We used D2.
Speaker 2: D2?
Kelly Caldwell: Yeah.
Speaker 2: And the second question I have for you, is can you tell me a little more about your CO2 cleaning?
Kelly Caldwell: Sure. So CO2 is basically using dry ice in tiny little pellets that is attached to a gigantic air compressor. Luckily for the lion, the city provided a space for this to be worked on. And it was sort of like a large warehouse, garage space. So pretty much, the action of the CO2 is it shock freezes the coating, and through thermal expansion, then sort of blasts it off the surface. Aside from the adverse effects of the abrasive cleaning that was previously used on the other lion, the CO2, you have a lot less to almost no residual cleanup. Because it’s sort of, not like a laser where it vaporizes it off the surface, but it almost does. So it was a lot sort of safer and more manageable treatment for cleaning.
Speaker 2: Right. And that leads me to the last question. Did you try any laser cleaning tests?
Kelly Caldwell: We didn’t try laser cleaning. While we do do laser cleaning, the options for it … Everything was beige. So the absorption rates for the laser vary because of the … Well, I don’t want to get super technical, but basically it’s not dark enough that laser would have worked.
Speaker 2: Right. You had needed contrast in this original surface to the coating.
Kelly Caldwell: Exactly, yeah. The acrylic coating was a weird cream color? That cream gray. But there was also … The coating wasn’t uniform, there were random blobs of epoxy that had been dripped on it. There was old core holes that had been filled with we didn’t know what. There was a very miscellaneous history of these once they came off the bridge in ’99. The other two are still sitting in that sort of lion outdoor sculpture graveyard that the city owns. One was used as a guinea pig to sort of do all the testing on one, and then the one that was in best condition went to city hall. The one that we worked on was sort of the next one, and then there’s the third one, and the guinea pig that are … What do you do? So.
Speaker 2: Thank you.
Kelly Caldwell is a conservator with over 10 years of experience as an archaeologist and conservator and is currently based in our Ottawa, ON office where she manages our Canada based projects. She brings a unique perspective to CSI based on her previous work experience, which largely involved excavation, collections management, conservation, and training on a range of materials and projects multiple countries. Kelly holds an MSc in Conservation for Archaeology and Museums (2009) and an MA in Principles of Conservation (2006) from the Institute of Archaeology at the University College London, specializing in objects and sites. She is a Professional Associate of the American Institute for Conservation (AIC) and a member of the Canadian Association of Professional Conservators (CAPC/ACRP).