VANESSA LU
CITY HALL BUREAU CHIEF
Call it the ultimate "green roof."

The Gardiner Expressway – the city's key commuter route into downtown – could simultaneously become a centrepiece park with the addition of a plant-covered upper deck as envisioned by a Toronto architect.

Similar to westside Manhattan's scenic – and instantly popular – High Line Park, which opened this month along the path of an old railway track three storeys above street level, Toronto's elevated expressway could offer a unique enhancement to the city's downtown, says Les Klein, founding principal at Quadrangle Architects.

"I've been appalled at the sheer folly of taking down the Gardiner," Klein said before yesterday's speech at the ideaCity event, where he unveiled his dream. "It's about thinking innovatively, keeping it, adding on to it, renovating it, and renewing it

"That's the fundamental part of the organic growth of cities."

His idea, dubbed the Green Ribbon, calls for the addition of a level about 8 metres above the highway's elevated section, from Dufferin St. to the Don Valley Parkway. Columns would be added to the side to anchor the new level, which would become a linear park stretching for 7 kilometres. Estimated costs range from $500 million to $600 million.

Quadrangle Architects is best known for taking old buildings and giving them new life. Examples include the BMW showroom near the Don Valley Parkway and 299 Queen St. W., the CHUM-Citytv building.

"I happen to love old structures. I'm not in love with every old structure. They have to have good bones, but the Gardiner has great bones," Klein said, noting it is also a critical traffic artery that hundreds of commuters depend on daily.

Over the years, various ideas have been floated for the expressway, which opened in 1965. While some have advocated tearing it down, complaining it's an eyesore and a barrier to the waterfront, others have touted solutions such as creating a park underneath.

None of those proposals has gathered steam.

Mayor David Miller and Waterfront Toronto officials support a plan to tear down a section just east of Jarvis St., saying it is fundamental for the waterfront's redevelopment. An environmental assessment is underway on that section, with a final decision not expected before 2011. The price tag is projected at $300 million.

Given the city recently endorsed making green roofs mandatory on buildings of a certain size and height, Klein suggests the Gardiner get the same treatment, along with solar panels and wind turbines to power new lighting along Lake Shore Blvd., which would also be beautified and made pedestrian-friendly.

"Instead of tearing down the Gardiner and sending hundreds of tonnes of material to landfill, and losing this critical connection to tie our city together, let's put a roof on it," he said, adding he has discussed his idea with councillors, though not Waterfront Toronto officials.

Among the benefits: reduced maintenance costs and enhanced safety, because covering the highway would eliminate the need for winter plowing and salting, and reduce the corrosion and deterioration of the roadway that costs millions each year to repair.

Other cities have used similar principles to create green community assets: Promenade Plantée in Paris, like High Line, turned an old rail viaduct into a park. New York created a busy market below the Queensboro Bridge.

The Gardiner was a symbol of progress when it opened, and Klein believes it would be a shame to remove it. "If you tear it down now, it is gone," he said. "I just think it would be horrible waste, because it's a great piece of civic architecture. It serves a vital function."

http://www.thestar.com/news/gta/article/653385

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