Stakeholder needs for ground penetrating radar utility location

In the UK alone there are millions of miles of underground utilities with often inaccurate, incomplete, or non-existent location records that cause significant health and safety problems for maintenance personnel, together with the potential for large, unnecessary, social and financial costs for their upkeep and repair. This has led to increasing use of Ground Penetrating Radar (GPR) for utility location, but without detailed consideration of the degree of location accuracy required by stakeholders — i.e. all those directly involved in streetworks ranging from utility owners to contractors and surveyors and government departments. In order to ensure that stakeholder requirements are incorporated into a major new UK study, entitled Mapping the Underworld, a questionnaire has been used to determine the current and future utility location accuracy requirements. The resulting data indicate that stakeholders generally require location tolerances better than 100 mm at depths usually extending down to 3 m, and more occasionally to 5 m, below surface level, providing significant challenges to GPR if their needs are to be met in all ground conditions. As well as providing much useful data on stakeholder needs, these data are also providing a methodology for assessment of GPR utility location in terms of the factor most important to them — the degree to which the equipment provides location within their own accuracy requirements.