The Georgia and Dunsmuir viaducts were designed to bring freeway traffic into Vancouver in the 1970s.

But when the freeway was never built, they remained as thoroughfares for bringing vehicles in and out of the downtown.

All of that will change as a result of Vancouver city council's 5-4 vote last night to demolish these structures.

It comes after four years of work by the city, which will free up two blocks of city land on the east and west side of Main Street.

The viaducts will be completely removed by 2020. According to the city, that will reduce traffic by 10 percent along Prior Street.

"This is a once-in-a-generation city building opportunity,” Mayor Gregor Robertson said in a news release. “There is no decision at the city that has been more scrutinized, studied, deliberated or consulted on than whether or not to remove the viaducts, and after four years, it is time to move forward.
 
“There are clear benefits for our city from the removal of the viaducts, whether it’s reconnecting Chinatown to False Creek, avoiding tens of millions of dollars in seismic upgrades, or building new affordable housing and bigger parks."

The viaducts currently carry six percent of traffic in and out of the downtown core. The plan calls for a new ramp to connect West Georgia Street with Pacific Boulevard.

Three NPA councillors—George Affleck, Elizabeth Ball, and Melissa De Genova—and Green councillor Adriane Carr opposed the plan.

The city has estimated that the entire project will cost $180 million to $200 million. 

"Approximately two-thirds of the cost is related to the engineering-related items such as structures, streets and utilities, with the other third related to parks and environmental remediation," a staff report states.

Of that, $14 million to $24 million will go toward replacement of Skateboard Park and changes to Andy Livingstone Park.

The staff report notes that it would cost $8 million to $10 million to repair and maintain the viaducts and another $50 million to $65 million to have them seismically upgraded.

The city has estimated that $300 million could be recovered by freeing up additional land.