Aftershocks in China collapse 420,000 houses

Some 5 million people were left homeless by the quake, and many of them are living in tents or makeshift communities that are clustered throughout the disaster zone.

Qi Xiaoqiu, the director of disease prevention at the health ministry, said the quake had knocked out much of the region’s health infrastructure, but 12 field hospitals had been put up and tens of thousands of health professionals were working in the zone.

“With the destruction by the quake, the living and sanitary conditions have worsened for the local population,” Qi told reporters in Beijing. “Their physical conditions are weakened (and they are) more vulnerable to disease.”

Diseases such as tuberculosis, hepatitis and diarrhea remained a threat, but so far no outbreaks had been reported, he said.

About 1,800 soldiers clambered up mountain paths to reach Tangjiashan with plans to dig and blast their way through the debris and drain the water, Xinhua reported. It did not say when the blasting operation would take place.

The Tangjiashan lake is the biggest of about 35 lakes created when the magnitude 7.9 quake sent millions of tons of earth and rock tumbling into some of the region’s narrow valleys. Some rising floodwaters have already swallowed villages.

Tangjiashan now holds 34 billion gallons of water and was rising by more than three feet every 24 hours, Liu said.

Xinhua said troops blasted several tree trunks with explosives on Tuesday to help clear rubble and were working around the clock to remove at least 1.8 million cubic feet of debris to build the channel, which would not be completed before June 5.

Pressure is building behind the dams as rivers and streams feed into the newly formed lakes. Officials fear the loose soil and debris walls of the dams could crumble easily, especially once the water level reaches the top and begins cascading over.

Adding to the threat, thunderstorms were forecast for parts of Sichuan this week — a foretaste of the coming summer rainy season that accounts for more than 70 percent of the two feet of rain that falls on the area each year.

Also in northern Sichuan in Qingchuan county, 1,300 people have been evacuated from Guanzhuang because of landslide worries. Local official Li Guoping said plans were being drawn up to evacuate all 23,000 people in the area if needed.

He said landslides that blocked rivers had formed 10 lakes, but only three had the potential to be dangerous if there were heavy rains.

“I worry about the start of the rainy season,” Li said.

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