GPR Survey Deliverables: CAD, GIS, L-Section, Report

Updated: 23 October 2026

What are GPR survey deliverables?

When people talk about GPR survey deliverables, they mean everything the survey team hands over once scanning ends. The radar and electromagnetic (EM) passes themselves are only the means of utility detection; what the project team actually uses is the record of what was found, where, at roughly what depth, and how sure the surveyor is about it.

A complete handover usually has two halves:

• On site: marks on the ground that guide the excavation or drilling crew in the days that follow.
• On paper or screen: a report, and depending on the order, depth profiles, drawings or GIS data that designers, owners and future contractors can refer to long after the marks have faded.

The scope of these outputs should be fixed in the work order, not discussed for the first time after fieldwork. Agreeing it early decides how the crew records data while scanning.

Why do deliverables matter as much as the scan itself?

A well-run scan with a weak handover leaves the excavation crew guessing about the underground utilities in its path. Three practical reasons make the outputs important:

1. Strike prevention. Marks and a findings table tell operators where to slow down, hand-dig or shift the alignment. Our note on utility mapping and strike prevention covers the cost side.
2. Design decisions. A route designer cannot work from paint on a road. Positions referenced to the route, with depths, are what let an HDD bore or trench line be placed between existing services.
3. Accountability. A signed report records what was surveyed, what was not, and the limits of the method. If something unexpected turns up later, that document shows what was known at the time.

Which types of deliverable can a GPR survey produce?

Ground marking

Paint lines, arrows or pegs in agreed utility colours, with approximate depth written alongside. Marks are short-lived by nature, so they suit work that starts soon after the survey.

Survey report

The core document. It lists each detected service with its position against the route or site, approximate depth at measured points, the detection method used, and notes on coverage and no-access stretches.

Radargram extracts

Selected radar profile images that show the radar signal reflections behind key findings. They help a reviewer see why a service was reported; our guide on reading a GPR radargram explains what those shapes mean.

L-section

A profile showing how deep each detected service lies over the length of the route. It is ordered as an L-section survey at ₹32 per metre instead of the ₹24 standard rate. The difference between the two is set out in L-section vs standard GPR survey.

CAD drawings and GIS layers

Findings drawn onto a route plan, or delivered as map layers with one layer per utility type. These are a separate, quoted item and never part of the per-metre survey rate.

Which terms should you understand before reading a deliverable?

• Approximate depth. Radar estimates depth from signal travel time, which depends on the soil's dielectric properties. Treat stated depths as estimates unless a trial pit has confirmed them; see how accurate GPR depth is.
• Depth reach. The penetration depth the radar actually achieved on a given stretch. Clay with high moisture content and salty soil raise signal attenuation and shorten it, whereas dry sand lets the signal travel further. A good report states it section by section.
• Confidence or quality level. A statement of how a service was identified – detected by radar only, traced with EM, or confirmed by exposure. The SUE quality levels explainer covers one widely used scheme.
• No-access area. A stretch the crew was unable to cover – parked vehicles, water, stored materials or a locked gate got in the way. Its absence from the findings means nothing was checked there, not that nothing exists.
• Unidentified anomaly. A reflection that looks like a buried object but cannot be tied to a known utility type.

How are survey deliverables produced, step by step?

1. Scope agreed. The client confirms route length, whether an L-section is needed, and whether CAD or GIS output is wanted.
2. Records gathered. Any existing utility plans, even partial ones, are collected so the crew knows where to look harder.
3. Fieldwork. Radar lines run along the route with cross-lines at chambers, junctions and crossings; an EM cable locator follows metallic utilities.
4. Marking. Findings are marked on the ground while the crew is still there.
5. Processing. Radar data is reviewed, depths estimated and doubtful reflections flagged.
6. Compilation. The report, any profiles and any drawings are prepared and checked against field notes.
7. Handover. Signed documents and agreed files go to the client, who should check that every stretch is accounted for.
8. Verification where needed. Trial pits or boreholes, on request, prove depth or identity at critical points.

What mistakes should you avoid when specifying deliverables?

• Leaving drawings unspecified. If the work order needs CAD or GIS output, say so in the enquiry. Adding it after fieldwork can mean re-checking field notes and delaying the handover.
• Assuming paint is the record. Marks fade under traffic and rain within days. Plan excavation close to the survey date and rely on the report afterwards.
• Ignoring stated limits. A blank stretch in a report is not proof of empty ground. Read the coverage and depth reach notes as carefully as the findings.
• Asking for an L-section everywhere. Depth profiles help where design depends on depth, such as crossings and crowded stretches. Elsewhere a standard survey may be enough.
• Mixing up route survey and fault locating. Finding a fault on a live cable is a different task, ordered separately.

How should GPR survey records be kept after handover?

Survey data loses value fast if it is filed and forgotten. Simple habits keep it useful:

• Store the signed report with the project's as-built records, not only in someone's email.
• Keep the original files alongside any PDF copy so a later designer can reuse the data.
• Note the survey date clearly; ground changes after every new excavation, so older findings need checking before reuse.
• Record which findings were later confirmed by excavation, which helps the next team judge confidence.
• Where GIS layers exist, keep each utility type as its own layer so updates can be made without redrawing the rest.

Where can you order these deliverables?

Mezux Touch runs route and site surveys with 58 company-owned GPR systems and in-house crews from Faridabad. Every survey comes with marking and a signed report; L-sections, CAD drawing sets and GIS layers are added when the order asks for them. Drawing and GIS work is described on our CAD and GIS utility mapping page, and all per-metre rates, minimums and discount slabs are listed in the GPR survey price list.