Five utility mapping mistakes that airborne GPR can help prevent

The challenge

Construction and excavation projects need an accurate picture of what is buried on site. If a utility is missed or placed wrongly on the map, crews can strike it. SPH Engineering points to reported incidents in the US and the UK where gas lines, water mains and power cables were hit because the mapping was incomplete, out of date or not shared.

The five mistakes

• Incomplete surveys. Missing even one line can create a safety hazard and delay the work.
• Old or wrong records. Utility maps age quickly, especially in cities where new services are added all the time.
• The wrong technology. GPR, electromagnetic locators and other tools suit different jobs. Using the wrong one, or none, gives a poor map.
• Ignoring depth. Utilities sit at different depths, often in several layers or under uneven ground.
• Poor communication. If the mapping team and the construction crew do not share location and depth, the map does not protect anyone.

The solution

SPH Engineering recommends airborne GPR as a preventive step. A GPR on a drone images the subsurface, picks up a wide range of buried features and gives a more complete map before digging starts.

The result: what airborne GPR adds

• Access to sites that are hard, dangerous or impossible to cover on foot.
• Faster surveys, because the drone flies pre-programmed grids automatically.
• Better accuracy, because each GPS-guided line is straight and evenly spaced.
• Extra data on the same visit, such as magnetometry, imaging and orthomosaic maps, plus options like methane detectors, thermal cameras and LiDAR.

Where this applies in India

Any project that digs near buried services can use the same check first:

• road widening, flyover and metro works in dense urban areas;
• city gas distribution and water supply pipeline projects;
• telecom and fibre trenching along highways;
• expansion work inside industrial plants and campuses with poor as-built records.

SPH Engineering's GPR training is also available through HobiTech.

The equipment, available from HobiTech

Ground penetrating radar	The article does not name a system. See our drone GPR systems.
Onboard computer	SkyHub by SPH Engineering with the SkyHub GPR software
Flight planning	UgCS - Drone Flight Planning Software, for pre-programmed survey grids
Training	SPH Engineering GPR training

Use-case article by SPH Engineering, published March 2023. This page summarises it in our own words; it describes general utility-mapping practice and incidents reported in the press, not a HobiTech project. Read the original article on SPH Engineering ↗