Engineers are considering using explosives to drain the lake before it bursts.

Liu Ning, Chief engineer of Ministry of Water Resources, said, "As the second batch of equipment arrives, the project will enter the second phase. We have to first clear these woods that stand in the way."

On Tuesday evening, rescuers blasted several tree trunks mixed in the blockage. At least 20,000 cubic meters of debris had been removed the same day.

The sluice is expected to be ready in about three to five days, and at least 50,000 cubic meters of debris need to be removed to build the diversion channel. But local authorities aren't taking any chances as evacuation has already started.

Lin Xin, vice mayor of Mianyang City, Sichuan, said, "The Tangjiashan barrier lake could burst in three possible ways. If a third of the lake bursts, nearly 158,000 residents in Mianyang would be evacuated. If half of the lake bursts, about 1.2 million residents would be evacuated. If the whole lake bursts, 1.299 million would be evacuated."

So far, more than 100,000 people in and around Mianyang City have been relocated.

(CCTV May 28, 2008)