A GEOTEC Underground Utility Mapping Survey is one of the most comprehensive services on the market, compliant with PAS 128 standard, utilising Electromagnetic Locating (EML) & Ground Penetrating Radar (GPR) as a minimum.

Example PAS 128 Underground Utility Mapping Extracts

Non-Invasive Underground Utility Mapping serves as GEOTEC's Core Business, where we have over 20 years' experience in detecting and mapping any buried known and unknown services and utilities that may be present within any given site.

This comprises metallic and non-metallic services, including Water, Power, Gas, Telecommunications, Fibre Optics, Drainage and other linear targets. GPR can also detect and map subsurface anomalies such as voids and obstructions.

Combined GPR & Utility Survey

Advantages of an Underground Utility Mapping Survey

  • Ground Penetrating Radar Data Post Processed.
  • Cross referenced against Statutory Records.
  • Permanent record at a single point in time.
  • Overlay proposed design solutions to assist with clash management.
  • Manhole Photo Schedules & Reports on request.
  • Results can be fed into 3D & BIM software.

Drawings provide:

- type of service,
- chamber extents,
- diameter & depths of services
- extents & depths of anomalous areas

Above all Underground Mapping reduces risk to those who dig and minimises disruption of the general public.

The following techniques and technologies are combined to achieve our objectives:

  • Ground penetrating radar (GPR),
  • Radio-frequency locators (EML) in active & passive modes,
  • Cover lifting, threading, signal induction.
  • Topographical Surveying to accurately record our findings to GPS

The responsibility for production of final results always lies with the Lead Surveyor; this task is not passed to anyone who has not physically carried out the survey.

Survey Request


Methods & Techniques

  • Radio Frequency
  • GPR
  • Resistivity / Imaging
  • Electro Magnetics
  • Micro-Gravity


GEOTEC Surveys Ltd have specialist training & accreditation to work in high risk environments such as the railways, substations, power stations, gas terminals, water treatment locations and pylon runs, as well as brown field sites, churches, schools, hospitals, urban environments and green field sites.

We work with our clients to cause as little disruption to their operations as possible by using internal and external Traffic Management Measures & working Out of Hours where necessary.

We are also able to support clients with Vehicle-mounted GPR Surveys within highways and large open sites to suit your needs.