About This Project
Thames Water’s 32m deep shaft at Walton on Thames was constructed in the early 1970’s to connect to a 2.5m diameter water tunnel. The shaft was engineered to make the best use of the available space across its 8 levels, as such there’s very restricted space inside, with a complex array of pipes, cables, valves and ladders and only one ingress and access point.
To progress a study for modifying the operation of the shaft, Thames Water needed a detailed BIM model of the internal shaft. The model was required to help their engineers design for new pumps, pipes and equipment, highlighting potential clash detection and showing how to maneuver around the confined space during the installation phase.
Thames Water turned to the team at Murphy Surveys to create a detailed and accurate BIM model of the site using 3D laser scanning and imagery survey.
“Our survey teams are fully trained and certified to work in confined environments, but with significant potential hazards on the site, safety was critical, and a safety specialist firm was brought onboard to support the project,” commented Matthieu Marsault, Laser Scanning Manager Murphy Surveys. “With just one entry to the site, the team needed to safeguard against potential electricity, atmosphere and water hazards over the 8 level, 32m deep shaft.”
“Moving anything in shaft was a challenging task, so we used a Leica P40 and a NCTech iSTAR 360 camera, which were small and rugged enough to maneuver around the site. A total of 130 scans were taken over a period of 2 days and the resulting data was processed using Revit. 3D panoramic imagery was created from the captured coloured scan data utilising Leica TruView to quickly and easily share the produced pointcloud data with the team at Thames Water.”
Thames Water’s Lead Engineer for the study said “We were investigating various options including squeezing large new pumps into the shaft and pipe-jacking a new pipeline through the wall to connect into existing pipework. Space is so tight in there, we had to be really sure from day one that all our dimensions were right. The 3D model was produced quickly and when over-laid with the new plant, provided very impressive visual evidence to stakeholders that we had done our homework and weren’t going to discover a show-stopping clash at the next phase of the project.”
With the successful delivery of the BIM model at Walton on Thames, Thames Water through their consultant engineer Stantec have commissioned Murphy Surveys to scan a similar shaft in Battersea, London.
Laser scan, BIM
Leica laser scanner
NCTech iSTAR 360 camera