Rehabilitation of the Potable Water Treatment Plant, Gatineau Sector (Civil)

This project covers the civil works portion for the expansion and increased production capacity of the Gatineau sector Potable Water Treatment Plant (DWTP).

The work carried out included:

• Installation of sheet pile retaining walls for four (4) sectors;
• Excavations up to six to twelve meters deep for the construction of new structures;
• Management and disposal of contaminated soils found on site;
• Management and treatment of excavation water before discharge into the city’s network;
• Driving over 200 piles for the deep foundations of the new reservoirs and contact basins;
• Installation of a 65-meter-long steel casing, 1,800 mm in diameter, at 12 meters depth beneath Saint-Louis Street for the new 1,200 mm reinforced concrete raw water pipe;
• Supply and installation of a 12-meter-deep concrete intake chamber weighing over 250 tonnes;
• Rehabilitation of underground services, including sanitary sewers, storm sewers, and water networks on the plant site;
• Renovation and leveling of the entire site, including curbs, sidewalks, pavements, concrete slabs, interlocking pavers, landscaping, and plantings.

Project highlights:

• Complex retaining and excavation methods;
• Management, excavation, transport, and disposal of over 45,000 metric tonnes, including more than 15,000 metric tonnes of contaminated soil;
• Installation of a new raw water pipe using trenchless methods at a depth of 12 meters;
• Execution of work while maintaining the plant’s water production;
• Strict schedule management imposed by the City.