New Developments in Multi-Sensor Condition Assessment Technologies for Large Diameter Pipe Infrastructure

SewerVUE Technology uses CCTV, LiDAR, and pipe penetrating radar (PPR) technology to gather quantitative data for underground pipe condition assessment. This MPIS system can be deployed on either a remotely-operated vehicle (ROV), or a float. In either case, the system produces an accurate 3D reconstruction of the pipe. To measure profiles and distances above the pipe flow line, the MPIS uses a time-of-flight LiDAR that is accurate to within 1.6 mm. Below the flow line, a pipe profiling sonar is used. This MPIS technology was employed for a project in Melbourne, Australia. The project saw the survey of 3521 m of pipe. This included 572 m of 600 mm (24 inches) reinforced concrete pipe (RCP), 1297 m of 750 mm (30 inches) RCP, 1165 m of 950 mm (37.5 inches) RCP, and 487 m of 1050 mm (42 inches) brick lined pipe. Through the use of radar, LiDAR, and CCTV, SewerVUE was able to assess the condition of these pipes and quantify deformations. This application of multi-sensor technology allowed the client to make informed decisions about the timing of future repairs. The same multi-sensor technology was used in a project at the Henderson-Urad site, located near Empire, Colorado. The project aimed to inspect two sections of pipe: 1606 meters of 600 mm (24 inches) diameter RCP, and 457 m of 1350 mm (54 inches) high density polyethylene pipe (HDPE). The surveyor remote operated vehicle was used to inspect the 600 mm pipe. Due to high flows, the 1350 mm (54 inches) HDPE pipeline was inspected using the MPIS float. In the 600 mm (24 inches) pipe, the LiDAR results showed small elongation of the pipe diameter, approximately 3 to 4 percent of the nominal diameter, along the horizontal axis of the pipe. The CCTV inspection showed the pipe to be in good overall shape, the only exception being occasional roots intruding at joints, as well as some structural defects scattered along the pipe. In the 1350 mm (54 inches) plant fill pipeline, the inspection revealed no reportable defects. Both pipes appeared to be in good shape which provided peace of mind for the client. The advanced pipe condition technologies outlined here are highly useful for generating detailed, accurate data that can provide the basis for utility owners to make informed decisions about cost allocation and timing of rehabilitation. Multi-sensor technology is both cost-effective and non-destructive, making it an excellent choice to help better understand the remaining life of pipes.