About Underground Utility Surveys
This survey integrates multiple techniques for locating buried utilities to ascertain the exact location and estimated depth of underground services and features within a site. To minimise damages to underground utilities and ensure safe excavation, equipment such as GPR, CAT & Genny, Manhole Tools, and GPS/Total Station are used to locate and map buried services.
To gather comprehensive information from a specific area, we open manholes to record the characteristics of the pipes and establish their connections, utilizing tools such as CAT, GPR, and Sonde. CAT and GPR survey of the entire site is then carried out. The results are subsequently georeferenced using GPS/Total Station for later processing in the office.
What is it used for?
Underground utility surveys allow buried assets to be detected and documented for future use. The results can be sent to clients in both AutoCAD and PDF.
Key Constraints of GPR for Underground Utility Surveys
Contrast
GPR relies on detecting the contrast in subsurface electrical properties between the buried utility and its surrounding material. Buried utilities will be detected by the GPR only when there is a contrast.
Utilities Type
GPR cannot directly identify the type of underground utilities detected. It only identifies contrasts, leaving the utility identification to interpretation.
Highly Conductive Soils
The deeper a pipe is buried in highly conductive soils, the harder it is to be detected with the GPR. The GPR pulse tends to attenuate more rapidly in highly conductive soils such as wet clay.
Ground Surface Obstructions
For best results, the GPR system must be in close proximity to the ground surface. Obstructions like tall grass, uneven ground, kerbs and bollards can disrupt radar signals and restrict the coverage area of the GPR.
