Large Brazilian dam cracks

Published 11 July 2006

The tallest — and newest — dam in Brazil seriously cracks as an underground tunnel beneath it collapses

Large cracks have opened in one of the world’s tallest dams just months after completion. The cracks formed after the 20 June collapse of a tunnel beneath the 200-metre-high Campos Novos dam in southern Brazil, and the reservoir rapidly emptied. At one point, 4,000 cubic meters of water (more than enough to fill an Olympic-size swimming pool) were rushing downstream every second toward a second dam on the river Canoas. Observers note that if the cracks and subsequent emptying of the reservoir were to occur during the rainy season, the damage would have been considerable. Between them, the two dams can hold more than two cubic kilometers of water.

The dam’s owner, Enercan, a consortium of Brazilian power companies, has revealed little about the accident. It is reported to have been trying to patch holes in a leaking tunnel since October, before the second tunnel failed catastrophically last month.