The Liberal government has launched a $1-billion project to rehabilitate the crumbling Supreme Court building, though key systems are at risk of failure long before any repairs begin.

A water-damaged section of the parking garage roof could collapse by the end of next year, and mechanical and electrical systems are predicted to fail by 2020 and 2021, says an internal document obtained by CBC News under the Access to Information Act.

But the heritage building, officially opened in 1939, is not slated for rehabilitation until 2023, partly because the high-court offices and chambers must be relocated to a building across the street that also needs extensive rehabilitation.

The West Memorial Building, vacant since 2008, will become the temporary home for the Supreme Court. (CBC)

Officials at the department in charge of the work, Public Services and Procurement Canada, are "closely monitoring the building for potential failures," spokesperson Nicolas Boucher said Wednesday.

"As an example, the parking garage is inspected regularly and mitigating measures can be implemented should a need arise."

Spokespersons for the Supreme Court referred all questions back to Public Services.

Temporary chambers

The project's estimated $1-billion price tag includes a massive overhaul of a nearby building on Wellington Street, the West Memorial Building, which will be a temporary home for the high court chamber and justices' offices while the Supreme Court building gets its five-year makeover through to 2028.

Public Services awarded the first big contract for the project last week, to PCL Constructors Canada Ltd., for $6.2 million. The Nepean, Ont., firm will do demolition work and roof replacement at the West Memorial Building over the next year. (The contract requires "zero activity visible" on Wellington Street until Aug. 31, out of respect for Canada 150 celebrations.)

Boucher said an architect is expected to be hired to design temporary chambers for the Supreme Court and the Federal Court somewhere inside the West Memorial Building.

The West Block on Parliament Hill is nearing the end of an $863-million rehabilitation, which includes the creation of a temporary House of Commons in the courtyard. (Catherine Lanthier/Radio-Canada)

The original Supreme Court building, almost 80 years old, is slated for steel-frame reinforcement to make it more earthquake resistant, as have all refurbished Parliament Hill buildings, because Ottawa is in an active earthquake zone.

Heating, air-conditioning, electrical, plumbing and other systems will be replaced entirely, and the building wired for internet and other modern information technology systems.

The parking garage will be repaired, and the escarpment at the back of the property, running down steeply to the Ottawa River, will be stabilized, Boucher said.

Other projects

The $1-billion project joins other expensive rehabs in and around Parliament Hill, including:

The $863-million project to update the West Block, on Parliament Hill, where the House of Commons will meet starting in fall next year as the Centre Block gets a 10-year rehabilitation, beginning 2019. The West Block work included the removal of 2,400 tonnes of asbestos.

The $425-million Wellington Building rehabilitation, a project nearly complete, fitted out with new offices and committee rooms for parliamentarians.

The $460-million, three-year Bank of Canada renovation project, now nearing completion.

The $219-million renovation of the Government Conference Centre, which includes a new Senate chamber that will operate while the Centre Block, which houses the Senate, is refurbished.

At least $81 million for repairs so far to the East Block on Parliament Hill, with more work to come.

The $100-million rehabilitation of the Sir John A. Macdonald Building on Wellington Street, formerly a Bank of Montreal branch, now complete.

The $136-million rehabilitation of the Library of Parliament, completed in 2006.

The Centre Block will get a major facelift, including the possible digging of a basement, starting in 2019 when "many of its major systems and components will be at risk of critical failure … with total failure predicted by 2025," according to Public Services. The price tag has not been announced but is expected to be as much as $1 billion over 10 years.

Public Services has said the total budget for the Parliamentary Precinct repairs is over $3 billion, but did not include the Supreme Court building or the Centre Block in the estimate.

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