Utility locating in Union County, NC
Before any excavation, trenching, or directional drilling begins, you need to know exactly what’s buried beneath the surface — and where. Underground Drilling provides professional utility locating services in Union County and the greater Charlotte metro, using electromagnetic detection, ground penetrating radar (GPR), and hydrovac potholing to identify, verify, and document underground utilities on residential, commercial, and municipal job sites. Calling 811 is required by law, but it only marks publicly-owned utility lines to the meter. Private lines, lateral connections, and site-specific infrastructure are left unmarked. We find what 811 misses.
One unmarked line can shut down your entire project.
Striking an unmarked utility line during excavation isn’t just a setback it can cost anywhere from $10,000 to $56,000 in emergency repairs, plus the liability exposure, project delays, and regulatory penalties that follow. Gas line strikes create immediate safety hazards. Fiber optic cuts can take entire commercial blocks offline. Damaged water mains can halt a job site for days.
Professional utility locating eliminates that risk. For every $1 spent on a professional locate, industry data shows an average of $4.62 recovered in avoided damage and downtime. It’s not an added cost — it’s the cheapest line item on any project budget.
| 811 vs. Professional Utility Locating | |
| What 811 marks | Publicly-owned gas, electric, water, sewer, and telecom lines — to the meter or demarcation point only |
| What 811 misses | Private lateral lines, on-site water loops, fiber beyond the demarcation point, private electrical feeds, irrigation systems, process piping |
| What we locate | Everything 811 marks plus all private underground utilities — the full subsurface picture before you break ground |
Our 3-Step Locating Process
Every utility locating job Underground Drilling performs follows a three-stage process designed to give contractors, engineers, and project managers the most complete and accurate subsurface picture possible.
Step 1: Locate — Electromagnetic Detection & GPR Sweep
We begin every project with a full-site sweep using electromagnetic (EM) locating and ground penetrating radar (GPR), depending on what utilities are present and what materials they’re made of.
Electromagnetic (EM) detection works by inducing a signal onto a conductive utility metal pipe, copper wire, steel conduit and tracing it with a receiver. It’s fast, accurate, and the standard method for locating gas lines, electrical conduits, metallic water lines, and telecom cables.
Ground Penetrating Radar (GPR) uses radar pulses to create a subsurface image of everything beneath the surface including non-conductive materials that EM can’t detect. PVC water lines, HDPE pipe, concrete conduit, fiber optic conduit, and underground storage tanks all require GPR to locate reliably. On commercial job sites with mixed-material utility infrastructure, GPR isn’t optional.
Concrete imaging is a specialized GPR application used when drilling, coring, or cutting into concrete slabs, walls, or foundations. A high-frequency GPR system maps rebar, conduit, post-tension cables, and voids inside the concrete before any core drilling begins preventing structural damage and protecting workers.
Step 2: Verify — Potholing & Daylighting via Hydrovac
Electromagnetic and GPR locating identifies horizontal alignment where a utility runs. But depth and exact position must be physically verified before drilling or excavation begins. That’s where potholing and daylighting come in.
Our hydrovac excavation equipment uses pressurized water to expose a small section of the utility without risking damage to the line. The exposed utility confirms exact depth, material type, and orientation. This step is especially critical before HDD bore planning, where even a few inches of depth variance can mean the difference between a clean bore and a costly collision.
| WHY IT MATTERS | Potholing before directional drilling isn’t just best practice — most bore contractors require verified depth data before finalizing a bore path. Underground Drilling handles both the locate and the verification in a single mobilization, eliminating the scheduling gap between two separate subcontractors. |
Step 3: Document — GPS Mapping & Site Reports
A locate is only as valuable as the record it produces. After every job, Underground Drilling provides documentation that field crews and project managers can actually use:
- Painted/flagged surface markings on the active job site
- Written utility depth and alignment report
- GPS-mapped utility records for digital site plans
- Deliverables compatible with project documentation requirements for commercial and municipal jobs
GPS-mapped records are especially valuable on large commercial sites where utility data needs to be shared with civil engineers, surveyors, or general contractors coordinating multiple trades. Having a documented record also protects the contractor if a dispute arises about pre-existing conditions.
Utilities We Locate
We locate every utility type on your site.
| Utility Type | Details | Method Note |
| Water lines | Metallic mains (EM) and PVC/HDPE private lines (GPR) | Including private loops and service laterals |
| Sewer & drain | Gravity and pressure sewer lines, drain tile, private laterals | Critical for bore planning and foundation work |
| Gas lines | Natural gas and propane distribution lines | High-priority locate — no exceptions |
| Electrical conduit | Power distribution, service feeds, site lighting conduit | EM for metallic; GPR for PVC conduit |
| Telecommunications | Fiber optic, coax, copper telecom, data conduit | GPR required for non-metallic fiber conduit |
| Irrigation lines | Private irrigation systems — often unmarked and post-meter | Common on commercial and municipal sites |
| Concrete structures | Rebar, conduit, and post-tension cables in slabs/walls | Concrete imaging via high-frequency GPR |
| Unknown/unmarked lines | Legacy lines from prior site development — especially common in older Union County commercial areas | Full GPR sweep recommended |
Who We Work With
Built for contractors, engineers, and developers not just homeowners.
Most utility locating companies serve residential customers doing fence installations and landscaping. Our core work is commercial and contractor-facing jobs where accuracy, fast turnaround, and professional documentation are non-negotiable.
| Project Types & Clients | |
| General contractors | Pre-construction locates, phased site locating as work progresses, bore path verification before HDD mobilization |
| Civil & site engineers | GPS-mapped utility data for site plan development, potholing for subsurface utility engineering (SUE) on design-phase projects |
| Developers & owners | Commercial site prep, due diligence locating before breaking ground on new development |
| Municipal projects | Infrastructure upgrades, road crossings, utility extension projects under NCDOT and Union County Water requirements |
| Specialty contractors | Concrete cutters and core drillers needing concrete imaging before cutting slabs, walls, or foundations |
| HDD & boring crews | Depth verification via potholing before bore path finalization — single-mobilization locate + verify workflow |
Union County has subsurface conditions most locating companies don’t understand.
Union County sits in the North Carolina Piedmont a region characterized by heavy red clay soils, weathered rock, and dense legacy utility infrastructure in older commercial corridors around Monroe, Indian Trail, and Waxhaw. These conditions affect locating accuracy in ways that matter:
- Clay soil attenuates GPR signal more than sandy or loamy soils — depth accuracy requires experienced interpretation, not just equipment
- Older commercial developments in Union County often have private lines that predate digital utility records and never appear in public 811 databases
- High-growth areas like Waxhaw, Marvin, and Wesley Chapel have layered utility infrastructure from multiple development phases — legacy lines often run parallel to newer installations
As a Union County contractor, Underground Drilling brings local site knowledge that out-of-area locating companies simply don’t have. We know the utilities, the soil, and the regulations including Union County Water requirements and NCDOT encroachment considerations for road crossings.
Utility locating and directional drilling under one contractor.
Most HDD projects require utility locating before a bore path can be finalized. When those services come from two different companies, you’re coordinating schedules, managing communication gaps, and hoping the locate data gets interpreted correctly by the drilling crew.
Underground Drilling performs both utility locating and horizontal directional drilling, which means the same team that reads the subsurface data is the team planning the bore. Locate findings go directly into bore path design — no handoff, no interpretation errors, no scheduling gap between mobilizations.
| RESULT | Faster project timelines, cleaner bore paths, and a single point of contact from pre-construction locate through completed utility installation. |