Opponents of the Tokushima dam argue that dams of similar design elsewhere have destroyed river habitats, blocking the flow of water and leading to an accumulation of sludge on the river bed.

ECONOMIST: Japan

Atoms of elements with boiling points below the temperature of a particular plate pass over it, just as water runs over a warm river-bed.

ECONOMIST: Nuclear waste

Divers, working in the pitch black in deep and torrid water, were able to find the car on the river bed and the bodies of four men were recovered.

BBC: Inquiry into four river deaths

But its bed was thick with well-worn river stones, testimony to uncountable seasons of floods and the persuasive nature of water.

CNN: The seven stones of simpler living