Most large excavation projects are easy to spot even before they begin with bright paint in all the right colors marking the ground like a treasure map with no treasure. It’s one of the most important steps and helps avoid cable strikes. But they still happen. A bucket takes a bite, a drill noses along, machines hum…and then, silence where there should be noise, lights off that should be on, or a blinking control screen that should be steady ― and someone says the phrase that launches a hundred questions, “We cut a cable.”
A cut cable feels dramatic because it interrupts modern life at the speed of electricity and light. But most of the time, it’s not a monumental disaster. It’s a problem that’s fixable.
What’s down there, really?
“Cable” covers a lot of ground. Power to buildings and campuses often travels underground in thick, insulated lines — picture a garden hose for electrons — sometimes directly buried, sometimes inside plastic or metal conduit. Big sites, like neighborhoods or hospitals, use medium voltage power, and smaller loads that might run on lower voltage feeders to lights, signs and outbuildings. Telecommunications often use fiber optics, which are made of glass as thin as human hair and carry light instead of electricity. Older or shorter runs might be copper phone lines or coaxial cable. Control and instrumentation cables are the nerves and reflexes of industrial plants, treatment facilities and large buildings, and include twisted pairs of wire, industrial Ethernet and specialty cables that can tell pumps when to start and stop and report water and pressure levels.
How damage happens
A strike doesn’t look the same for every cable.
- A bucket tooth can shave a power cable without cutting it, leaving a cosmetic scrape that becomes a real problem months later when moisture and voltage turn a nick into a weak spot. When a power cable is nicked, the crew might get a show — arcing, smoke, a loud pop.
- Fiber optic lines fail differently and, in some ways, more gracefully. Cut them and the light stops. Kink, crush or bend them, and the lights are dimmed. The connection becomes sensitive to distance, wavelength and weather. A single fiber optic line cut in a regional network can impact traffic routes, call centers response times, payment systems and healthcare needs.
- With control and instrumentation wiring, a clean cut is obvious. A nick that breaks the cable’s shield — the thin layer that keeps electrical noise out — creates gremlins. Suddenly, a level signal picks up the hum of a nearby motor or a digital network starts dropping packets like a bad video call.
Stories of cable strikes, repairs and lessons learned
A directional drill crossed a medical office park to bring in a new fiber connection. Marks were down for a medium voltage power feeder, but the crew didn’t find it where they expected during potholing and assumed it was deeper. When the drill met the feeder, there was a flash and the sound of every HVAC unit in the park stopping at once. Crews opened the trench, removed the damaged section, installed the proper splice and tested the cable’s health. It passed and was put back into service. Patients were rescheduled and offices reopened in a day and a half. Most of the questions later centered on how the locate drifted from the actual buried path and why the crew stopped short of exposing the line where the crossing mattered most. The big money in the claim wasn’t copper and labor. It was lost appointments and mitigation costs.
A fencing contractor at a shopping center skipped the 811 call for a quick run of posts in a back lot and damaged a fiber lateral that served the area. Calls rerouted across the network, some dropped, and payment terminals were impacted. The fix was calm, surgical and passed the same day. Technicians exposed the fiber on both sides, fused the glass back together inside a burial-rated box and checked the light levels. The part of the claim that grew wasn’t the splicing; it was the hours that nearby businesses spent working around a strained network. The lesson that stuck with the center’s management was how fast a small oversight can spread and how unremarkably a well-done repair brings everything back.
Developing a comprehensive investigation
Key elements in an investigation include photos and measurements, copies of the 811 ticket and responses, and site permits. Another important step is to have a discussion with the firm that wrote the plan showing where potholing was supposed to happen, confirm if the work happened, and request repair records showing the kit that was used, who did it and if it passed the test. A complete investigation should also include the business interruption timeframe, and a simple before and after summary that describes what was broken, what was done, if it worked, and maps with the new splice locations and route changes marked, if available.
When claims related to cable strikes occur, a failure analysis and an origin and cause investigation provide technical information to confirm what happened. EFI Global specializes in analyzing failures such as arcing, insulation breakdowns and signal interference. Our origin and cause specialists help establish liability and clarify what went wrong. This expertise is essential for an accurate diagnosis in defensible claims.
It’s possible a company is unaware they hit a cable even months or years ago and a forensic investigation of the scene can no longer take place. In those cases, a technical consultant can review financial demands from utilities or their third-party agencies. Consultants not only need to verify what was damaged and to what extent but have details to determine the proper repair scope and costs associated with that scope. They may have to look into liability by reviewing state dig laws and excavation regulations, case law and what is recoverable in a third-party claim, among other details.
Improving the claims process
The claim files with the least friction have the same ingredients. Early photos and measurements that make the scene obvious, and all the information mentioned above. Many adjusters ask for technical details early in the process because they see how much easier the back half of the claim gets when someone who does this every day helps define the front half. Working with failure analysis and origin and cause experts can ensure the necessary aspects are examined. When the ground is complicated, some targeted questions and the right specialists can save time, money and second guessing.