CASE STUDIES
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Gunn Water Main
Longest Guided Boring Completion
PROJECT SUMMARY
Gunn is a small hamlet on the north shore of Lac St. Anne, just off Highway 43 – twinned highway that serves as the main route between Edmonton and Grand Prairie. A 159 m (522 ft) water line installation was required to cross this 4-lane highway and rail line. This was at the limits of what is considered possible for a guided boring machine (GBM) on a project requiring precise alignment. While other companies concluded this crossing could not be done, The Tunneling Company was up to the challenge.
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KEY CHALLENGES
The stakes were high on this project. The design involved a shallow crossing over a great distance. If the accuracy was off, even slightly, there was the risk of a potential highway closure.
This would have been a difficult completion under ideal weather conditions. However, The Tunneling Company’s crews and equipment were further tested when the outside temperature dropped below -30°C. In such extreme cold, our team had to devise a solution to keep the drilling mud circulating. A lubricating line was used to achieve the right consistency.
Today, this remains among the longest pilot tube completions in Canada using a GBM. This project illustrates The Tunneling Company’s capabilities and is a testament to the skill and dedication of our crews.