RENEE MONTAGNE, host:
As we've been reporting, hundreds of thousands of survivors of China's earthquake are now in danger from flooding from lakes created by landslides stopping up rivers. They're called quake lakes now and Chinese troops are working without a break to drain one of them. It's above the city of Beichuan, which is in danger of bursting its banks.
NPR's Rob Gifford joins us now from Chengdu, China. And Rob, that sounds like a pretty serious situation there.
ROB GIFFORD: It is very serious indeed. And as you say, this is one of a number of lakes that has been built up. The reason these lakes have formed is that when the earthquake happened on May 12th, huge landslides were triggered and they blocked some of the many rivers that flowed through Sichuan.
There are some 1,300 rivers in Sichuan Province, and more than 30 of these have been blocked. The most serious one is this one at Tangjiashan. And they are working round the clock, as you say, to try and clear - to create a channel, so that water can be fed out of this blocked lake and back to the river, but at the same time not allowing it to come gushing out and flooding out. They want to control the water as it comes out to prevent flooding down below.
MONTAGNE: And altogether, any way of knowing how many people are under threat?
GIFFORD: Well, 150,000 people have already been evacuated from just below this one particular lake. The government has told us that much. But actually, further down below, towards the plains - this is up in the mountains - in the path of where any flood might come, there are about 1.3 million people who would be affected. So it's really very serious indeed.
And the government is trying to fly in more equipment - digging equipment. The roads are blocked, so they're not able to take stuff up there by road. All the diesel that's needed for the digging equipment has to go by helicopter. And that has been affected by the weather, because it's been raining today and the helicopters haven't been able to take off. So it's really a race against time to get these channels dug to let the water out in a safe manner.
MONTAGNE: Now a series of aftershocks, as we've been hearing, have occurred along the quake's fault line. I mean, some of these aftershocks are the size of what would be counted as big earthquakes, so hundreds of thousands of houses have fallen down during these aftershocks. Are they expected to continue?
GIFFORD: Well, seismologists are saying that there will be more aftershocks. In fact, they've said there've already been 150 of them. As you say, some of them have been up to a level of six magnitude, most of them somewhere between four and six. And some of them you'd barely even notice. But this is a concern.
And the other thing that seismologists are saying is that often after a quake of this magnitude - the big quake of 7.9 - you would expect something bigger than has happened as an aftershock. You'd expect something - maybe something like 6.9 or 7, one level down - one notch down on the scale. And that hasn't happened.
So although the people of Chengdu have really gone back to business as usual in as much as is possible here around me, I think everyone is very aware that something could come. And people, especially in the villages and the towns near the epicenter, are bracing themselves in case there are more aftershocks.
MONTAGNE: Rob, thanks very much.
GIFFORD: Thank you very much indeed.
MONTAGNE: NPR's Rob Gifford speaking to us from Chengdu, China, not far from the epicenter of China's earthquake. Transcript provided by NPR, Copyright NPR.
