Remember that gaping sinkhole that suddenly appeared a week ago in the middle of Fukuoka, a Japanese city on the western island of Kyushu? Well, the locals promptly got to work and fixed it all up – just one week later (erroneously reported in some places as two days, but still impressive). That is ludicrously efficient, considering the beast was 30 meters (98 feet) wide and 15 meters (49 feet) deep.
This chasm was so huge, and formed so rapidly, that it threatened to engulf nearby buildings like some sort of overeating Sarlaac pit. Working around the clock, Japanese workers began repair work almost immediately after it formed, and the street is now safe to use for cars. Safety checks also took place during this incredibly small window of time.
It wasn’t just a void that needed to close, either. Traffic lights, sewage pipes, water mains, and other infrastructural damage also needed to be repaired – and they were, in record time. The mayor of the city told reporters that the ground there was now 30 times as strong as it was before the sinkhole formed.
There are rumors that local construction work on an underground line caused the collapse, although officially, it’s not clear what actually caused the sinkhole to form in the first place. In this case, there were no fatalities and, incredibly, no serious injuries.
Generally speaking, in cities, sinkholes form when – surprise surprise – the earth beneath them is eroded, normally by sudden flows of water or by human excavation. In the natural world, slow erosion tends to cause more gradual and less dramatic collapses, but the same basic mechanism applies.
Although this rather sizable sinkhole in Japan was enough to make headlines, it’s far from the most voluminous of its kind.
Back in 2010, a sinkhole dramatically made its debut in Guatemala City that was 20 meters (65 feet) across and 90 meters (300 feet) wide. Triggered by seismic activity by a nearby volcanic eruption, as well as an inflow of water from a tropical storm, it managed to consume a three-floor-high factory.
In any case, social media was ablaze with compliments for the Japanese workers – often at the expense of users' own local workforces.
Others, though, took a curious sort of inspiration from the whole ordeal.