For the billions living in the world’s active fault zones, earthquake readiness is a way of life. This October, cities across the planet participated in the worldwide ShakeOut earthquake readiness drill, the largest single-day preparedness drill of its kind.
In the U.K., ShakeOut day was just another Thursday. According to the British Geological Survey, some 20 to 30 quakes are felt in Britain in the typical year, but most are quite small. The strongest quakes, such as the infamous Dogger Bank earthquake of 1931, occur offshore. Had the 6.1 tremor’s epicenter been closer to or under Britain itself, the damage and loss of life would likely have been far more extensive.
Is the U.K. Ready?
But emerging data suggests that the U.K. may be more vulnerable to a major temblor than is widely believed. Newly discovered “super-deep” faults under the Home Counties resemble California’s San Andreas fault network, which is capable of producing massive quakes. Periodic tremors, such as the 2014 shaking in Rutland, reveal a gap between the U.K.’s actual earthquake risk and the British public’s perception thereof.
Solid Doesn’t Mean Earthquake-Proof
Public attitudes are malleable; building stock, less so. The U.K.’s aging housing and commercial stock is well-built for the country’s climate, but the prevailing materials used in older buildings — brick, mortar, wood, concrete — simply aren’t built to withstand serious shaking.
Brick warehouses and sheds fare far worse in moderate quakes than resilient Nissen huts, for instance. In most parts of the U.K., building new steel structures from the ground up is less dear than retrofitting existing heavy-frame buildings to withstand quakes.
Building Better Stock
What would it take to prepare the U.K.’s building stock for the inevitable tremor?
In short, a multi-pronged approach. Modern commercial structures and high-rises are already built to withstand high winds and moderate to severe earthquakes. Most detached houses, flat blocks, and council estates require more extensive shoring-up. Industrial and auxiliary structures, such as sheds and garden houses, are the lowest-hanging fruit: as noted, it’s fairly routine and not particularly costly to replace them with more resilient steel structures.
The horribly tragic Grenfell Fire, accelerated by cheap, flammable cladding, reminded Brits that better buildings save lives. It’s past time the country turned its attention to the looming danger of earthquakes, whose devastating effects impact entire cities and counties — not just one or two unfortunate buildings.
Tremors in Unexpected Places
The U.K. isn’t the world’s only underrated earthquake zone. Other unexpected places, such as the south-central United States, are vulnerable to potentially devastating tremors. In 1811 and 1812, a series of violent tremors measuring 7.4 to 7.8 on the Richter scale ripped through a then-sparsely populated swathe of the American frontier along the little-known New Madrid fault, temporarily reversing the Mississippi River’s course.
Were a quake of similar magnitude to occur today, the city of Memphis — home to more than a million souls — could be leveled.
Whether and when the U.K. is really due for a major tremor is an open question. But it would be foolish to discount the possibility much longer.