Japan: Pillars of resilience
Prone to typhoons, floods, and earthquakes, Japan has developed unique skills in coping with natural disasters. With deep expertise in everything from physical infrastructure to rapid recovery, the country has made disaster-proofing into an exact science.
[…]
Tokyo has taken active steps to reduce flood risk. As the city’s population grew in the twentieth century, the Naka and Ayase River Basins to the south of Tokyo saw rapid suburban expansion accompanied by a dramatic change in the land utilisation profile. Between 1955 and 2010, built-up areas’ share of total land use there rose from 5% to 52%, while rice paddies and fields’ share declined from 68% to just 33%. The local topography did not help matters: not only is the area bowl-shaped—meaning that excess rainwater tends to stay put—but it contains five rivers with unusually low gradients—meaning that water is slow to drain into the sea.
[…]
The MLIT had already built several above-ground river discharge ducts to channel the area’s flood waters when it started constructing an underground flood control channel in 1993. Consisting of five shafts that collect runoff from five rivers, direct it along a subterranean tunnel, then pump it up into another river and thence to the sea, the Tokyo Flood Control Channel—or Metropolitan Outer Area Underground Discharge Channel (MOUDC) as it is officially known—cost nearly $3 billion and took 13 years, from 1993 to 2006, to build.
[…]
Of course, constructing elaborate physical infrastructure can never be a universal solution to the problem of flooding. Floods will inevitably occur somewhere as a residual disaster risk. In that case, the goal should be to minimise the danger by providing early warnings that enable people in the affected areas to take the necessary precautions.
[…]