Why Canada Blasted a Huge Hole Outside its Parliament

On July 30, 2020, workers began digging a massive pit outside Canada's Parliament in Ottawa. This marked the start of an ambitious construction project beneath the nation's most important building, with repeated blasts over three years creating a massive hole, dwarfing Canada's equivalent of Big Ben. This work is crucial for the future of a building that has stood for over a century.

Ottawa, chosen by Queen Victoria as the capital for its strategic location between English and French-speaking regions and defensible forests, is home to Canada's Parliament. The original Center Block, housing the House of Commons and Senate, was built between 1859 and 1876 but burned down in 1916. A replica, completed in 1927, included the Peace Tower, a 70% taller monument to WWI victims, still standing today.

Despite its resilience, the Center Block has significantly deteriorated over the last century. Surveys revealed eroded concrete, water infiltration, rusting steel, and a lack of earthquake protection, posing a major risk in an area prone to seismic activity. Additionally, the building lacks modern high security and adequate visitor facilities, which are crucial given its role and attraction of over 3 million visitors annually.

The Center Block is undergoing a $5-billion upgrade, the largest and most complex project of its kind in Canada's history, led by Public Services and Procurement Canada. The project involves a 23-meter deep pit, blasted with explosives, to accommodate a massive underground welcome center. Concrete pouring for walls, stairs, and elevator shafts began even before the full excavation underneath the main building, which currently has no basement levels.

A crucial part of the renovation is installing a base isolation system for earthquake protection. This involves separating the entire Center Block from its foundation. The building will be supported on temporary posts, then placed on a new structural grid of steel and concrete, with 800 piles driven into the ground. Over 500 base isolators, acting as giant shock absorbers, will be installed between the building and its new foundation, a pioneering application for a historic structure.

Workers face monumental challenges, including securing the Peace Tower's pinnacles with straps and monitors to prevent vibration damage during construction. Restoration teams are meticulously cleaning and restoring 365,000 exterior stones using advanced laser technology to remove dirt without damaging the stonework. Inside, the building has been stripped to its structural elements, with over 20,000 heritage assets, 50 rooms, 250 stained-glass windows, and hundreds of sculptures undergoing restoration and preservation.

During the extensive renovation, MPs, senators, and staff have relocated to the West Block and the Senate of Canada building. The project is expected to complete in 2031, with the Center Block reopening fully a year later. The revitalized parliament will feature a stunning new underground welcome center, providing a secure, accessible entrance with a main hall showcasing the Peace Tower's foundation and skylights. This ensures the Center Block is restored, modernized, and ready for another century of service to Canadians.