Owen Wagner peers through the lens of a blocky instrument called an auto level that sits atop a yellow tripod in Duke Gardens. He’s looking, or sighting, through the viewfinder reticle (a series of crosshairs) to take measurements of the distance to a pole held by his partner, Damien McCabe.
“Can you lean over?” Wagner asks. “It’s tilting towards you.” As McCabe does, the tall, graduated staff he’s holding, called a stadia rod, closes in on perfectly vertical. Wagner sights again and jots a few numbers in a notepad he’s holding. “Okay, this is 3.28 feet above that,” he says, and lets McCabe know he can move along. They’ve started at one corner of a concrete bench on the circle in the Azalea Garden above the Terrace Gardens, moving their way from corner to corner, from bench to wall to urn. They have one hundred points to locate, so they don’t dawdle.
“This bench is named for someone,” McCabe says. “That may be useful in naming points.”
Wagner and McCabe are freshmen studying civil engineering, and for a class called Engineering the Planet, they are learning to survey. They are doing what engineers have been doing since there have been engineers: figuring out exactly where things are, in relation to one another. And despite entire flocks of satellites and the availability of laser-shooting surveyors’ tools that could do the whole thing with the touch of a button, they are learning to use equipment not much different from that used by George Washington when he surveyed the Great Dismal Swamp.
“I do teach them how to use the total station,” says David Schaad, professor of the practice and director of undergraduate studies in civil and environmental engineering. “But I want them to practice the process, and total stations are so quick. The students need to comprehend how the survey is conducted.”
We say it all the time: facts on the ground.
We mean, let’s not talk about concepts, or ideals, or how things might be. Let’s look at actual reality. Ground truth. You are here. If you start digging on different sides of a mountain to meet in the middle, you’d better meet in the middle. You have to know exactly where you are and where you’re going. So every spring, freshman civil engineering students use traditional surveying tools to learn to do exactly that: find the actual facts on the actual ground. They show up all over West Campus with tripods and rods. They don’t wear hard hats like you’d see on a construction site, “but I require them to wear close-toed shoes,” Schaad says – the tripods have sharp points to dig into the ground to provide a stable base. “We don’t want to put anything into their foot. But otherwise they’ll just be knocking around and scratching their heads, getting frustrated.”
Schaad may do a better job of preparing them than he thinks, because the students in his class who swarm the Gardens and the engineering quad don’t seem confused; they sight, make notes, move, sight again.
In many ways surveying is simple: It puts into practice all that stuff you learned in geometry and trigonometry. You start at a spot, and then you measure angle, distance and slope to somewhere else. Once you have a couple distances and a couple angles, you can side-angle-side your way around the world, and surveying tools give surveyors highly accurate ways to measure or compute angles and distances. Wagner and McCabe use their auto level and a tape measure to sight distances and elevations. Other students use theodolites, which measure both vertical and horizontal angles.
And yes, to be sure, a total station can make measurements almost independently, and on a modern construction site not just tools but heavy equipment like bulldozers can be actively controlled by satellites. Analog surveying equipment is to civil engineering what pencil and paper are to drawing: the original tools. Schaad says engineers had better learn those original tools before they cede control to automatic ones. “The goal of this exercise is that they will be able to level, like, level a building pad, right? Every engineer should be able to level a building pad, or tell whether or not a pipe is going downhill.”
The students agree. “It’s a really interesting hands-on project,” says Corinne Ladha, a freshman civil engineering major pointing a tripod-mounted theodolite at her partner holding a stadia rod across Science Drive. “I feel like this is the first time that we’ve taken something we’ve learned during lecture and we’ve actually gone out to use the math and trigonometry that we’ve been learning since high school, and we’re applying it to an actual real-world situation.”
Which is the point. These students will become civil engineers in charge of all kinds of projects involving, say, sewer pipes; just trusting the computers is a bad look. “Any project that impacts the health, safety or welfare of the public has to be overseen by a registered professional engineer,” Schaad says. “Every road, every building, every bridge, every storm water system.” To prepare them for that responsibility, he says, “our goal is to teach them an introduction to what they do in surveying. This is something I still have done on occasion. You know, I’m out at the project site, and I’m like, ‘I don’t think that looks right. Let’s pull out survey equipment and we’ll shoot some quick shots.’” So out the new class comes out, every spring, with their tripods and tools.
And get the facts on the ground.