City ready to forge ahead on reducing seismic risk
Assessment will be used to encourage safety upgrades in private buildings
The City of Vancouver is pushing ahead on a promised plan to reduce the seismic risk of private buildings that will hinge on a new technical earthquake risk assessment.
The city is working with Natural Resources Canada on sophisticated computer modelling that will include factors such as soil type on potential earthquake damage to buildings in Vancouver. The soil research is being funded by Emergency Management B.C.
The earthquake risk modelling — along with a socio-economic analysis — will help determine policy options to reduce seismic risk, said Katie McPherson, the City of Vancouver’s chief resilience officer who is responsible for the initiative.
Ultimately, it’s city council that will decide on any new measures to reduce seismic risk in privately owned buildings, possibly sometime in 2020.
“I would say this is the first time these efforts have been undertaken with such momentum and partnership across all three levels of government. And that’s hugely important,” McPherson said.
“There’s no doubt it’s going to be a tough conversation for our council to have and that’s why it’s even more important that there are multiple stakeholders at the table for this.”
The work to reduce the earthquake risk of private buildings followed an investigation by Postmedia News published in 2016 that revealed the city had failed to create a proactive plan to reduce the seismic hazard of the city’s older private buildings, numbering in the thousands, despite identifying a need to do so more than two decades ago.
The city first developed a plan more than 20 years ago because scientific knowledge was increasing about the risks of an earthquake, including of the so-called Big One, from the slippage of tectonic plates off the coast of Vancouver Island. Scientists peg the probability of a major quake — including on land — in a populated area in B.C. at 30 per cent within the next 50 years.
The City of Vancouver lags behind other West Coast jurisdictions such as California, which has a decades-long history of tackling seismic risk in buildings, including private buildings. That state has used tax and fee incentives to reduce seismic risk and also required mandatory seismic retrofits.
This year, Portland, Ore., introduced mandatory seismic retrofits for unreinforced masonry buildings, a type of brick building also constructed in Vancouver.
The City of Vancouver’s initiative is meant to deliver policy options by the fall of 2019, according to the city’s October 2017 earthquake preparedness strategy. The city hired a dedicated seismic manager in the fall of 2017, Micah Hilt, previously an urban planner with the City of San Francisco.
Hilt helped develop a mandatory retrofit program for wood-frame buildings that would be at risk in an earthquake.
The city has also put together a seismic technical advisory committee that includes groups representing architects, building owners, earthquake engineers, geoscientists, the federal government and the province. The committee also includes academics and the Vancouver school board.
McPherson said the next step will be to make public the new earthquake risk assessment computer modelling when it is ready. That will be a time for public engagement, said McPherson, although she could not say when that will be.
Murray Journeay, a research scientist with Natural Resources Canada and a member of the advisory committee, said the idea is to improve their modelling by incorporating research on soils by Western University in London, Ont., and research underway at the University of B.C. on the earthquake performance of buildings specific to Vancouver.
That includes concrete buildings constructed in the ’70s, ’80s and ’90s, as well as wood-frame buildings that have different characteristics than those built in California, which is what the model relies on now, said Journeay.
The modelling will produce results down to the neighbourhood level, he said.
The City of Vancouver has already cautioned that municipalities do not have the financial capacity to offer huge incentives for seismic retrofits and that other levels of government would need to play a role.
The City of Vancouver developed plans to reduce the seismic risk of older buildings in 1994, 2000 and 2011, but never followed through.
For example, for the 1994 initiative, the city considered mandatory seismic assessments, deadlines for mandatory upgrades, public disclosure of the seismic risk of buildings and possibly even requiring signs on buildings that weren’t upgraded. Also considered at the time were incentives for seismic upgrades, such as waiving building permit fees and offering property-tax relief or low-interest loans.
There is no law in Vancouver or any other B.C. municipality that requires older buildings to meet modern seismic safety standards. Some buildings in Vancouver have received seismic upgrades when changes of use or major renovations have triggered bylaw requirements.
But of the more than 1,100 buildings included in a seismic risk assessment by the city in 1994, hundreds appear to have had no upgrades, Postmedia’s 2016 probe discovered.