The system relies on a high-resolution, ground penetrating imaging radar (GPIR) for detecting water pipes, leaks and damages within the water pipes and for producing images of the inspected zone. This sensing device uses FM signal information to determine the underlying structure characteristics such as pipe location and size, and is able to detect water pipes made of all types of materials. The images from the underground medium are generated by an imaging algorithm, using Ultra Wideband (UWB) signal processing where short signal pulses are sent towards the ground. The resulting reflected waves are measured and recorded, thereby creating underground images by using real-time electromagnetic technology.
The penetration capability of the radar is up to 2 meters into the ground. The survey time, including detection and imaging, is 10 seconds per meter along the pipe axis implying that surveying one kilometre of the pipeline will take 2.8 hours. During this inspection, the radar system is mounted on a 4 wheel drive vehicle equipped with a lap top computer and an antenna system with transmitter-receiver analogical/digital signal processing units which is placed in front of the car. In each position, the system can survey a length of 5 meters along the pipeline, detecting water leaks and cracks that are more than 5 cm in size.
The outputs from the inspections are used as an input to a decision-support system (DSS), developed as a strategic planning tool for rehabilitation management of the damaged pipes. The DSS contains a risk-based methodology for rehabilitation decisions considering economic and social risks for instance. A Data analysing step provides information on leakage as well as the structural reliability of the water pipelines and the quality of the water in the affected pipelines. Analyses are based on pipe data from the inspections and information regarding the loads on the pipes, the pipe materials’ deterioration and the interaction between the soil and the pipe structure.
The project consortium included ten partners with expertise in water pipes from research institutes, operators and industry in several European countries, supported by the European Commission under the Sixth Framework Programme (FP6), a grant funding programme.
The results from the project have been tested in relevant conditions, but need some further development before the system can be commercialised. Specifically, the radar system needs to be further improved to be able to provide 3D resolution to the images, something that is currently on development within the National Technical University of Athens in Greece. The technology readiness level of the system is therefore 8 on the TRL scale.