It’s a typically rainy day in January at 2 p.m.

Downtown cores are packed, with businesses in full swing after workers have returned from the holidays.

Then the earthquake hits Vancouver. Most people hear it before they feel it — a low, rumbling sound similar to a freight train. Closest to the epicentre, violent shaking, which lasts 10 to 20 seconds, knocks people off their feet.

Tall buildings sway. Some buildings collapse, and many shift and crack.

The ground ruptures in some areas. There are fires from broken gas lines and flooding from the recent rains increases as some dikes failing.

Windows break and glass falls. Many people who run outside suffer injury or death from falling and flying objects.

Thousands are trapped.

Medical facilities are overwhelmed.

This is the grim picture painted of a hypothetical, worst-case scenario earthquake that hits Vancouver.

The scenario — a shallow earthquake of magnitude 7.3 temblor directly beneath the city — was chosen to provide the basis for drafting an emergency earthquake plan by the province.

Such an earth quake, the plan noted, would be “exceedingly rare.”

In the scenario, 18 per cent of Metro Vancouver buildings are estimated to receive extensive damage, while 12 per cent are most likely to receive catastrophic damage.

The death toll is estimated at nearly 10,000 in Metro Vancouver with more than 128,000 injuries.

In a separate worst-case scenario for an earthquake beneath Victoria, deaths were estimated at nearly 1,500 and injuries at more than 19,000.

The human casualty figures are among the first such estimates for Metro Vancouver, as governments grapple with how to prepare for a severe earthquake that scientists predict for B.C.

Vancouver and Victoria were chosen because of their population density, political and economic significance and because of critical infrastructure such as the Port of Metro Vancouver.

Because the earthquakes are hypothetical scenarios, and because computer modelling always has uncertainties, the effects of an earthquake, particularly one that took place farther from Vancouver or Victoria, could be less extreme.

For example, a 2015 University of B.C. analysis, using a different scenario of a strong and deep earthquake in the Strait of Georgia (not a worst-case scenario), predicted 22 deaths and 38 serious injuries in Metro Vancouver. In Christchurch, New Zealand, where a similar shallow crustal earthquake hit in 2011, 10 kilometres away from the city, 185 people were killed.

“We wanted a scenario that had catastrophic impacts that required us to build a scalable and flexible plan,” says Kathryn Forge, a seismic specialist with Emergency Management B.C. “If we plan for the worst case, then we can tailor our response accordingly for other earthquakes or lesser hazards.”

A major rain and wind storm that swept B.C. this past weekend gave residents and entitites such as B.C. Hydro a reminder of the importance of disaster preparedness.

B.C. did not model a mega-thrust earthquake off the coast of B.C. — often called the “big one” — because it would take place at some distance from the population centres.

The new earthquake response plan — released at the end of July — sets up a framework for such elements as a logistics management system to obtain and transport personnel, equipment and supplies to areas of need.