GPR surveys and mapping
We locate underground pipes and cables with radar, map them with sub-centimetre GPS, and deliver a drawing you can use.
How a GPR survey works
Ground penetrating radar is a geophysical method that uses radar pulses to image the subsurface. It sends electromagnetic pulses in the microwave band of the radio spectrum into the ground and detects the signals reflected from the surfaces below.
Once the services have been located, their position and depth can be marked on the ground, or plotted and drawn up as a DWG or PDF with sub-centimetre accuracy using a specialised GPS system.
- Method
- Non-destructive radar scan
- Marked
- Position and depth, on the ground
- Positioning
- Specialised GPS, sub-centimetre accuracy
- Delivered as
- PDF or DWG drawing
GPR and electromagnetic locating in one pass
GPR can only detect a difference in density in the soil below, not what the service is. This can be a problem when locating live electrical cables, because some cables are too small in diameter to show clearly.
Conventionally, equipment using the electromagnetic principle is brought in after the first scan to solve this. We have invested in state-of-the-art equipment that lets us do both at once.
- Detects
- Changes in soil density
- Helps with
- Thin live electrical cables
- Visits needed
- One
Maps that fit the job
Our mapping can be as simple as a record of services for a residential complex presented as a PDF.
It can also be as detailed as a DWG drawing with sub-centimetre accuracy, including contour lines, for engineering purposes.
- Simple
- Record of services as PDF
- Detailed
- Sub-centimetre DWG with contour lines
- File formats
- CAD (DWG) and PDF
When a survey helps
- Before excavation starts, to confirm the depth and location of all underground services.
- Before upgrades or new work on a site, such as around water back-up tanks.
- Before leak detection, to find potable water services.
These are the kinds of jobs we have done for clients such as Rand Water, Netcare and Vodacom. See recent work.
Questions about GPR surveys and mapping
Does a GPR survey damage the ground?
No. GPR is non-destructive, so nothing is dug up.
What do I receive after the survey?
The location and depth of the services are marked on the ground, and mapped for you as a PDF record or a DWG drawing.
What is a DWG drawing?
DWG is the file format used by CAD software. Engineers and designers can open it and work directly from your survey. We also supply a PDF.
Can GPR identify what each service is?
Not by itself, because it only sees changes in soil density. We scan with GPR and electromagnetic locating together to help identify live electrical cables.
How accurate are the maps?
Services are located with GPR and plotted using a specialised GPS system with sub-centimetre accuracy.
How do I get a quote?
Send the quote form or call us on 074 539 5123. Tell us where the site is and what you need located.
Need underground services located and mapped?
Tell us about your site and we’ll come back to you with a quote.