A twin-prop Chinook helicopter shatters the calm of the Dutch countryside, hovering just metres from a canal before dumping four huge sandbags into the water: welcome to Operation Cloudburst.

The five-day exercise simulates catastrophic floods from a "water bomb", an ever-present fear in a country where 60 percent of people live below sea level and climate change is making things worse.

Originally published on doc.afp.com, part of the BLOX Digital Content Exchange.