Lower Mainland, British Columbia
What a major earthquake does to the Lower Mainland
The shaking lasts minutes. Here is what fails, and why the outages can last weeks or months.
What happens after the shaking?
Hours0–24 h
Power, phones and water fail in the first hours
Days1–7 days
Help reaches main routes before side streets
The taps are dry and the shops do not restock, because food arrives by truck on the same broken roads. Phones fade as cell-site batteries run down, and cards stop working. Crews clear emergency routes first, and local streets wait. The toilet may stop flushing on the first day.
Weeks1–8 weeks
Months2 months +
Standing homes can stay closed for months
A building can be standing and still be closed for months behind a cordon. Contractors and engineers are hard to find, because the whole region needs them at once. The province’s plan assumes people stay in the region while this goes on.
A household gets through those weeks on what it already has at home.
Every system comes back on its own schedule
Start with the one you depend on most.
Communications
Cell-site backup power lasts hours to days, and no rule sets a minimum.
Electricity
Up to two thirds of downtown customers could lose power for several weeks.
Water
Breaks under rivers and inlets take the longest to repair.
Sanitation
Without running water, toilets in apartment towers stop working.
Natural gas
Restoring gas requires a visit to every affected building.
Transportation
A bridge may survive an earthquake without being usable afterwards.
Port, airport and ferry terminals
The airport model expects damage to every bridge onto Sea Island.
Fuel
A service station with full tanks and no power dispenses nothing.
Food
Fresh food depends on regular deliveries.
Dams and reservoirs
The 2024 engineering reviews do not publish an earthquake finding.
Housing
Cordons and failed utilities can keep people out of standing homes.
Health care
Most hospital buildings in the region predate the current seismic code.
Safety and conflict
Most people help one another after a disaster. Theft and violence are the exception.
Where help comes from
A coast-wide earthquake leaves fewer outside agencies able to help.
Why this site exists
My name is Thomas Tartière. I live in downtown Vancouver, and in the French consulate’s emergency plan I am the volunteer contact for the French community in this part of the city. Preparing for that meant reading what has been published about a major earthquake here. Public guidance mostly covers the risk and what to do while the ground is shaking. What happens over the following weeks and months is in technical reports written for specialists.
In 2015 I heard Janos Toth go through the earthquake vulnerability of British Columbia’s infrastructure one system at a time. Years later, when my first child was born, that talk is what got me to put together an emergency kit. This site takes the same approach, using published documents, most of them written by governments, utilities and the engineers they hire.
About this site has the rest of the story, How this site works explains the method, the sources page lists every document, and contribute explains how to report an error.
Start with food and water
- British Columbia asks every household to keep at least two weeks of emergency supplies. Most households in the region have not put together a kit of any size.
- You do not need to assemble everything at once. Check what you already have, then add water and food that keeps. The preparation guide shows how much to keep and what to add next.
Sources on this page
Numbered in the order they are cited. Each entry links back to where it is used.
- [1]ReportEarthquake Vulnerability of BC's Critical InfrastructureJanos Toth (Enginomix Consulting Inc.) · 2015Open the document ↗
- [2]ReportEarthquake and Tsunami Preparedness GuidePreparedBC / EMCR, Province of BC · 2024Open the document ↗
- [3]ReportEmergency preparedness pollResearch Co. · 2021Open the document ↗