國家地理:Quake Lake Blasted 唐家山堰塞湖排洪成功

Chinese soldiers used anti-tank weapons to blast away rocks and mud, holding back waters in an earthquake-formed lake that threatens more than 1 million people living downstream. Soldiers fired at rocks to dislodge enough debris to speed the drainage of waters in Tangjiashan Lake in Sichuan Province. CCTV reported that the runoff channel was getting wider and deeper, helping to reduce the water level in the lake that was formed after last month's devastating earthquake.
"We fired at the rock from a closer distance to make sure that the water gets through the channel. Usually we shoot from about 100 meters away, but this time we did it from 50 meters, gives a better result than shooting from further away."
Other troops have been deepening the channel and digging on a second spillway. Officials fear that the so-called quake lake could burst its banks and cause catastrophic flooding if the water level is not brought down soon. Authorities were on alert both for increased rainfall and new aftershocks that could weaken the dam, or send more debris plunging into the lake.
More than 250, 000 people downstream have been evacuated in recent weeks, adding to the turmoil created by last month's massive earthquake in Sichuan Province. Government officials have downplayed the threat of imminent flooding, though a variety of factors such as rain and aftershocks could set off a dam collapse.
The Tangjiashan Lake is the largest of more than 30 created by last month's quake. The lake was formed when rubble from a massive landslide set off by the deadly May 12th earthquake, blocked the flow of the Tongkou River, also known as the Jianjiang.