PRIVATE UTILITY LOCATING

Private Utility Locating & SUE Support

The 811 locate marks the public side. Everything else buried on your property — site loops, irrigation, old fuel lines, abandoned infrastructure — is your responsibility to find. We map it with ground-penetrating radar, flown or surface-run, and deliver it as engineering-grade geometry.

The Gap an 811 Ticket Leaves Open

Call 811 before any excavation — always, and without exception. But understand what that ticket actually buys: member utility operators mark their own facilities, generally up to the meter or service point. Everything past that point is private, and private lines are routinely absent from the marks. On a commercial site that can mean electrical loops between buildings, gas runs to shop buildings, irrigation mains, storm laterals, septic components, old fuel or waste-oil lines, and whatever a previous owner buried and never drew.

Industry damage data tells the story plainly: a large share of utility strikes involve lines that no locate ticket was ever going to mark. The excavator assumed the paint told the whole story. It never does.

Private utility locating closes that gap. It is a deliberate survey of what is actually in the ground on your side of the meter, delivered as marks on the surface and as mapped geometry your engineer can design against.

Where This Fits in SUE

Subsurface utility engineering, standardized under ASCE 38, grades utility information by quality level: QL-D is records research, QL-C adds surface visual evidence, QL-B is geophysical designation of position, and QL-A is exposed and surveyed. Most damage happens on projects that never got past QL-D — a design drawn from decades-old as-builts that were optimistic the day they were printed.

Our work supports the QL-B tier: systematic geophysical designation of what is present and where it runs, tied to real coordinates with RTK positioning. When a project requires sealed SUE deliverables, we work under the project's licensed engineer or bring in our licensed partners — the field data is ours, the stamp is theirs, and the client gets both without hiring twice.

How We Work It

Records first. We start from whatever exists — as-builts, permits, aerial history — because radar interpreted against records beats radar interpreted against nothing.
GPR coverage, matched to the ground. Surface-coupled radar where the site allows it, drone-mounted radar where it does not — flooded ground, active operations, turf that must not be tracked, and large open areas where a cart grid would take days.
RTK positioning per trace. Every radar line is coordinate-referenced, so a reflector is not "about twenty feet from the fence" — it is a mapped position.
Marks and map together. Field marking (paint and flags) for the excavator, digital geometry for the engineer. The map survives after the paint washes off.

Deliverables

Geo-referenced utility map — located linework exported as DXF, CSV, or GIS-ready formats
Depth estimates with the velocity basis stated, flagged as estimates rather than dressed up as measurements
Confidence ratings per segment — clearly located, probable, or inferred, so nobody designs against a guess without knowing it was a guess
Marked-up site plan and photo documentation of surface marks
Interpretation report stating method, coverage, soil response, and what the survey could not resolve

When It Works — and When It Doesn't

GPR finds boundaries between materials, which means it can detect non-metallic pipe that electromagnetic locators miss entirely — PVC, HDPE, clay tile, concrete. That is its distinctive strength. Its distinctive weakness is soil: wet, conductive clay attenuates the signal and can shrink useful depth sharply, and a small-diameter plastic line deep in heavy clay may simply not return a usable reflection. We say so when that is the case, and we recommend verification potholing on anything critical before excavation. A confident map with an honest uncertainty statement is worth more than a tidy one without.

DJI M300 RTK with Zond Aero GPR antenna hovering low over golf course turf beside a water hazard, tracing buried irrigation lines

Tracing an undocumented irrigation network across a golf course — the turf is the asset, so the survey flies instead of driving a cart across the greens.

Private utility locating is a mapping and damage-prevention service. It does not replace the statutory 811 one-call locate, and Northern Drone is not a licensed engineering or land surveying firm — where sealed SUE or survey deliverables are required, we perform the field work in partnership with licensed professionals who review and stamp the final product. Read the full licensure disclosure.

Frequently Asked

Questions About This Service

Doesn't calling 811 cover this?▾

No — and you should still always call 811 before digging. The one-call system marks facilities owned by member utility operators, generally up to the meter or service point. Private-side lines — between buildings, past the meter, irrigation, old fuel lines, abandoned infrastructure — are the property owner's responsibility and are routinely unmarked. That private side is exactly what this service maps.

Can GPR find plastic pipe?▾

Often, yes — and that is GPR's main advantage over electromagnetic locating, which needs a conductive line to trace. Radar reflects at material boundaries, so PVC and HDPE can return a signal. The honest caveat: detection depends on soil, depth, and pipe size. Small plastic lines deep in wet clay are genuinely difficult, and we will tell you when conditions are against it rather than promise a clean map.

How accurate are the positions and depths?▾

Horizontal position is the strong suit — every trace is RTK-positioned, so located segments are mapped to survey-grade coordinates. Depth from radar is an estimate derived from signal velocity in your soil; we state the velocity basis and treat depths as guidance, not gospel. Anything critical should be verified by potholing before excavation, and we say exactly that in the deliverable.

What do the marks and map look like?▾

On the ground: standard color-coded paint and flags the excavator can work from. In the deliverable: geo-referenced linework in DXF, CSV, or GIS formats, a marked-up site plan, depth estimates, and a per-segment confidence rating — clearly located, probable, or inferred — so the engineer knows the difference between measurement and interpretation.

Related Services

Underground Utility Mapping

The full service — methods, deliverables, and how we fly it.

Pipeline Depth of Cover

Cover verification and corridor mapping for pipeline operators.

LiDAR Mapping

See accuracy, deliverables, and how we fly it.

Who Buys This

Sector-specific detail on how this service is used and what the deliverables look like in context: Construction & Engineering · Municipal & Government · Oil & Gas

Know What's Down There Before the Bucket Finds It

Tell us the site, what records exist, and what you are trying to avoid hitting. We will tell you honestly what radar can resolve in your ground — and where verification digs should back it up.