For any construction crew, it’s a chronic headache: buried power, gas and water lines on project sites, some defying the best efforts to sleuth out the hidden hazards.
The stakes always are intense. Mishaps involving utility assets compromised during construction can stall projects, damage equipment and materials, disrupt service, draw financial penalties and, in worst-case scenarios, imperil workers who each day go to their job site with every expectation of returning home safely.
The issue isn’t likely to abate as underground infrastructure expands by the year. But game-changing — even life-changing — technology in the form of ground-penetrating radar (GPR) is taking out much of the guesswork, putting crews in more control of their own destiny.
Black & Veatch was among the early adopters of the innovation, underscoring the global critical infrastructure leader’s championing of safety — and project success — as foundational to its culture, reputation and bold vision of what’s possible.
The company’s takeaway: GPR, while still an emerging construction technology, has proven its worth in an industry where knowing decidedly what’s below can dictate whether a project goes smoothly or goes south.
Often, utility assets predictably were buried along rights-of-way. Other times for so many decades, crews trying to scope out underground power lines and water and sewer mains did it the old-fashioned way, relying on schematics, blueprints or utility maps that frequently proved inaccurate or incomplete as infrastructure constantly changed.
When in doubt, crews resorted to “potholing,” making small test holes to accurately detect what lies beneath. Backhoes have proven popular, but their favor has waned because of the impreciseness and the risk of accidentally hitting a line. Hand digging was the last step.
Enter GPR, a trusted ally of Black & Veatch since not long after two of its professionals went to a trade show and first learned about the latest breakthrough.
GPR goes to work the moment it’s affixed to the bucket — or scoop — of an excavator. The operator gently scrapes the bucket across the earth, detecting what’s below through a linear scan. That data then is processed and sent in real time to the operator’s display monitor in his cab before the process is repeated along the same strip to confirm the findings.
Such radar-integrated equipment is easy to install on buckets 18, 24 or 36 inches wide, and it’s even simpler to operate — with amazing accuracy, poised to become the industry’s standard.
GPR in action: real-world results
In this project’s case, Black & Veatch followed its traditional road map of due diligence, first contacting the legally required 811 “Call before you dig” service that for free marks the location of buried gas, water and power lines.
At least those it can find. As they pressed for more details before undertaking the project’s task of burying cable four to five feet deep, Black & Veatch crew leaders grew more unsettled by the unknowns of what else lies beneath, always suspecting there was more.
In that small town, the person with the best handle on it all had retired, taking that intimate knowledge with him. Answers from other locals were vague: “We saw the gas line go in 20 years ago, but we don’t know exactly where,” the conversation typically went. Even the expected depths of utility lines often proved inaccurate because years of soil erosion from farm fields, in some areas, reduced the depth by as much as two feet.
The push for answers — and safety — prompted Black & Veatch to first use potholing before enlisting GPR, and it paid off.
GPR-equipped buckets proactively bought by the company pinpointed at least eight buried assets previously undetected, averting potentially disastrous strikes.
Although one such line was an obsolete gas main, trapped gas inside it was leaking and still volatile in the event of inadvertent contact. Other gas lines zigzagging beneath were active, along with a sewer line the utility wasn’t aware existed. A gas line that was supposed to be 10 feet below was just half that depth, making it vulnerable to accidentally being hit by crews laying cable.
At the highest levels of Black & Veatch’s leadership, there’s a mantra: Nothing is so urgent that the company’s crews can’t take the time to do it safely. The company’s migration to GPR epitomizes that, knowing that using the technology may take more time but is worth any inconvenience.
“We want people to go home the way they came in — maybe a little dirtier and more tired, but safe,” said Mary Korte, a Black & Veatch construction support operations manager for renewable energy, focusing mostly on pre-mobilization. “To take the time to do it right, ensure we’re not going to get someone hurt, not impact the community and keep people working, that’s what it’s about.”
“The intent here is this isn’t a one-off,” Ben Anderson, a Black & Veatch project manager for solar energy project, added of the company’s leveraging of GPR. “We saw the value, and the client saw it and was extremely happy with the results.
“The reality is that if we hit a gas line and it exploded, there’s no telling how much that would cost us financially, reputationally, people getting hurt or killed. Can’t really put a price on people going home the way they came in.”
