Between August and November 2023, Brownline Canada was contracted to complete several crossings along a 36” steel pipeline in British Columbia. The purpose of these crossings was to construct a leak detection conduit used as part of the pipeline company’s leak detection system.
Leak detection conduits
These leak detection conduits were for crossings completed using the Direct Pipe Installation (DPI) trenchless method. With this method, it was not possible to attach these leak detection conduits to the pipe during installation, unlike the HDD method where the conduits are attached during pipe pullback. This is why separate HDDs were needed in parallel to the gas pipeline.
Leak detection systems, like those used by this pipeline company, rely on highly sensitive fibre sensors capable of detecting vibrations and noise that could indicate a possible leak. This technology enhances the safety of pipelines and enables continuous and real-time monitoring of the conditions surrounding a pipeline.
Five HDD crossings
The leak detection conduits were drilled parallel to the installed steel pipeline, with proximity as close as 2 m / 7 ft. With this proximity and the requirement for high accuracy, the Drillguide GST was the ideal steering tool to provide guidance for this kind of project.
Of these five HDDs across British Columbia, the longest was 676 m / 2218 ft long. The other four ranged from 155 to 282 m / 509 to 925 ft.
The shortest HDD had a very tight radius (175 m / 574 ft) and crossed under two large gas pipelines. The other HDDs included crossings under British Columbia Highway 1 and the Coldwater River (twice). Brownline’s Pressure-While-Drilling service was used to monitor downhole pressures while drilling in these sensitive environments.
Additionally, GPS track was used for a secondary verification of the drill head’s position. Thanks to the accuracy of our tools, these drills were all completed successfully and within design specifications.