Before the project begins or during the construction phase, Detect Réseaux precisely identifies underground networks using multiple complementary techniques: ground-penetrating radar and electromagnetic induction.
These techniques are non-intrusive (no underground work is required to access the pipeline) and non-destructive. Failure to identify or locate a pipeline correctly can lead to the use of unsuitable earthmoving equipment or a lack of preventive measures, endangering people, machinery, and existing infrastructure.
As a guarantee of success, Detect Réseaux provides public works contractors, project managers, project owners, concessionaires, and construction companies with its cutting-edge equipment and underground structure identification techniques.
Ground Penetrating Radar Detection: Fast, Accurate, and Reliable
Ground penetrating radar detection of buried utilities can identify underground structures up to 3 meters deep, whether they are plastic (connections, etc.), electrical, or concrete (wastewater or stormwater networks, etc.). When the ground penetrating radar passes along the roadway, existing structures appear on the screen thanks to the reflected electromagnetic waves. The Detect Réseaux technician marks the entire identified network and its information (elevation, depth, etc.) on the ground using various standardized colors. The surveyor then uses the plotted positions to reconcile them on a plan.
Induction-based detection: accurately locating and tracing underground utilities
A complementary technique to ground-penetrating radar, induction-based detection uses electromagnetic fields to locate metallic underground utilities. A signal transmitter induces a cable with a specific frequency, allowing the technician to accurately determine the position and path of the targeted utility using a paired receiver.
The equipment used by Detect Réseaux teams automatically measures the depth of located utilities. When coupled with a GPS receiver, it enables full mapping of networks such as electricity, telecommunications, street lighting, signaling, and steel gas pipes.
By combining this method with a traceable rod, we can also detect infrastructures such as fiber optics, drainage systems, and empty conduits.
Georeferencing Equipment
Various types of georeferencing equipment are used to perform a topographic survey of networks detected via ground-penetrating radar and induction. This operation enables the creation of a georeferenced as-built plan, integrating the identified underground utilities into a known geographic coordinate system. Two main methods are used:
• The first (and most commonly used) involves real-time visualization of the surveyed utilities via a GPS and/or total station connected to a tablet equipped with Land2Map software. This traditional surveying method streamlines data processing.
• The second method is based on photographic surveying: using a pole-mounted camera, the underground networks and their markings on the ground are documented through high-resolution photos.
Orthophotograph with ground markings
As-built plan
Using these images, Detect Réseaux produces orthophotographs to generate a georeferenced as-built plan of the identified underground utilities. These plans comply with standardized requirements regarding scale, connection points, color codes, symbols, and more.