Electricity

On 10 November 2025 BC Hydro filed its initial application to the BC Utilities Commission for the West End Substation Project, which would replace the substation that supplies much of downtown Vancouver. In the section headed “Seismic Concerns” it wrote:

BC Hydro attaches neither duration to a particular earthquake: its wording is “in a large seismic event” and “depending on the magnitude”.

BC Hydro filed this in support of a project it wants approved, so the seismic consequence is the case being made. It is also the owner of the asset, in a regulatory filing, citing a seismic assessment of its own substation and conceding something against its own interest.

From a footnote in the same filing:

A post-disaster building is one the code expects to keep working after the earthquake. A one in 2,475 year ground motion is shaking severe enough that it happens on average once in 2,475 years, so the higher the number, the rarer and the harder the shaking. Murrin was commissioned in 1947 and Dal Grauer in 1952. About 60 per cent of Murrin’s assets and 78 per cent of Dal Grauer’s are at or near the end of their working lives. [1]

BC Hydro’s own assessment of the alternatives:

Until the new West End substation is in service, much of downtown stays on Murrin. Its in-service date is July 2032 at the earliest, and the regulator has not yet ruled on it. [1]

BC Hydro’s filing of February 2019, which the regulator’s record files by fiscal year as F2020, already stated that Murrin sits on seismically unstable soil, that about half of the switchyard supplying both substations is vulnerable to settlement and to liquefaction, where saturated soil loses its strength and behaves like a liquid while the ground shakes, and that load served from both “may experience a prolonged outage after a seismic event”. [2]

That same filing also counts about 95,000 customers in the downtown study area. [2] The customer count and the two thirds come from different filings six years apart, so multiplying one by the other would produce a number of people nobody has published.

At Second Narrows, BC Hydro’s 2021 revenue requirements filing says the transmission line crossing structures “have been assessed as being critical, and at risk of sustaining damage, including possible collapse, during an earthquake of less than 1:475-year frequency”, and that losing the crossing “would result in load curtailment in the Metro Vancouver area”, which means cutting power to customers on purpose to keep the rest of the network up. [3]

Cost, in-service date and construction start were all listed as to be determined, and the project sits in a category for future prioritization, with no commitment to build. [3]

Murrin and the Second Narrows crossing are two named assets, and neither is a statement about the rest of the network.

In January 2011 BC Hydro stated in a press release that “BC’s electrical infrastructure has been built to withstand even a severe seismic event, such as a one in a 2,475 year event.” [4]

Against that stands BC Hydro’s own 2025 assessment, above: Murrin not operable at one in 1,000. [1]

Both are BC Hydro. The 2011 sentence is design intent for the system as a whole, fifteen years old. The 2025 finding is an engineering assessment of one critical asset that does not meet it.

What BC Hydro builds now is built to that standard. The Mount Pleasant substation, part of the Vancouver City Central Transmission project, is designed to operate after a disaster, with ducts and cable vaults installed below the zone where the ground would deform. [5]

In its 2021 filing BC Hydro reported 10 spare power transformers against a fleet of 672 at 60 kV and above. [6] The same section of its 2019 filing gave 572 and the same 10 spares. [2] Both describe the spares strategy as existing “to minimize impacts in the event of a failure”, in the singular, and neither connects it to an earthquake, to simultaneous losses, or to replacing many units at once.

No lead time for a replacement transformer is published anywhere in BC Hydro’s regulatory record. In the United States, average lead times for power transformers rose from around 50 weeks in 2021 to roughly 120 weeks, more than two years, by 2024. [7]

Those are US market figures and not a forecast for British Columbia. That is what a utility is waiting on when it says years. A substation that loses its transformer bank is in a queue behind every other buyer.