Total Dismantling of two Pylons in the Middle of the St. Lawrence River, QC

Located in the middle of the river at the Deschambault-Grondines level, this challenge involved complex work for which an innovative methodology was developed that made it possible to shorten the schedule and reduce costs. The planned equipment, some custom-made, was assembled and tested on the ground to analyze and mitigate risks. The assembly of the hydraulic scaffolding, the 20 t crane truck, the hoist mast and the electric manlift were a great success. Interestingly, the upper part of one of the two pylons was dismantled to be assembled and re-erected at La cité de l'énergie in Shawinigan.


  • Total dismantling
  • Recycling/reclamation of metals
  • Waste Management
  • Structural engineering
  • Consulting services


  • Very strict HSE requirements
  • Complex logistics
  • Environmental protection
  • Very tall structures (142 m)
  • Management of weather conditions (wind, rain and lightning in height)
  • Dust management


Cité de l’énergie de Shawinigan

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