MIANYANG, China - About 80,000 people were evacuated Tuesday from downstream of an unstable earthquake-created dam that is threatening to collapse, and troops rushed to carve a trench to drain the water before it floods the valley.
The threat of flooding from dozens of lakes swelling behind walls of mud and rubble that have plugged narrow valleys in parts of the disaster zone is adding a new worry for millions of survivors.
More than 30 villages were emptied and the people were being sent to camps like the one outside Jiangyou, where an Associated Press reporter saw 12-15 people crammed into each of about 40 government-issued tents pitched on a hillside overlooking the river.
"We were told that so far it is the safest place for us to stay if the dam of the lake crashes," said Liu Yuhua, whose village of Huangshi was one of those emptied. "But we will have to move farther uphill if the situation turns out to be worse."
Troops on Tuesday used explosives to blow up tree stumps that were hampering heavy-duty excavators that were airlifted by helicopter in recent days to the newly formed Tangjiashan lake near the town of Beichuan, the official Xinhua News Agency reported.
The magnitude-7.9 quake that struck Sichuan province May 12 sent a mass of dirt and rocks tumbling in the valley about two miles above the town in a spot not reached by roads, plugging a river that is now forming the lake.
Elsewhere in the region, workers also used explosives to level some buildings that were left teetering by the quake