CHENGDU, China — Water churned through a drainage channel and engulfed empty towns Tuesday after Chinese soldiers blasted away the debris that kept an earthquake-formed lake threatening more than a million people downstream.
Sichuan province's Communist Party chief, Liu Qibao, declared "decisive victory" after more than half the 66 billion gallons of water drained off by early evening, easing pressure on a dam formed when the quake triggered a landslide of mud, rocks and other debris, the official Xinhua News Agency reported.
More than 250,000 people had already moved to high ground due to concerns that the barrier holding back Tangjiashan lake could break. About 1.3 million people live downstream.
Fearful that the possible deluge would endanger refugees and residents, China ordered soldiers and police to work nonstop for four days to dig a diversion channel and blast away the debris with dynamite, bazookas and recoilless guns.
In the narrow valley town of Beichuan, which was flattened in the quake, a rush of murky brown-gray water from the Tangjiashan lake washed away a metal pedestrian bridge spanning a river on Tuesday and scraped away at river banks. But today the water appeared to have subsided and was calm.
The swirl of muddy water roaring past towns and villages swept along trees, barrels, television sets, refrigerators "and the occasional dead bodies of quake victims," Xinhua reported.
Towns downstream remained on alert for possible flooding in case the water breached unstable banks.
"The best situation is to completely clear out the water in the Tangjiashan lake before the flood season. The water level is likely to linger around 720 meters (2,300 feet) for a period of time," said Water Resources Minister Chen Lei, according to Xinhua.
Floodwaters seeped into riverside houses in the largely evacuated town of Qinglian, a resident said.
"Everybody feels lucky that it didn't submerge the streets and the neighborhood," said Wu Zhenxing.
In the city of Mianyang, the Fujiang river flowed high and swift under a key railway bridge but stayed within its banks.
Also Tuesday, searchers discovered the wreckage of a helicopter that crashed deep in the mountains May 31 while ferrying people injured in last month's quake, Xinhua said.
The remains of the five-person crew and 12 quake victims were found at the crash site near the town of Yingxiu, it said. The wreckage was spread over a wide area.
Staff at Wolong, the world's most famous panda reserve, buried a 9-year-old female who was killed in a landslide triggered by the quake. Another Wolong panda, Xiao Xiao, is missing. Forty-seven other pandas still live at Wolong, while others have been moved to Beijing and Sichuan's provincial capital of Chengdu.
The 7.9 magnitude quake on May 12 killed 69,146 people, and 17,516 are still missing, the government said Tuesday. About 5 million people are homeless.
Earlier, China's security czar stressed the need to maintain order amid a struggle to shelter millions left homeless by the quake and scattered protests over alleged corruption linked to shoddy school construction.
Zhou Yongkang demanded police and legal staff "solve disputes and help maintain social stability," the Communist Party's official newspaper, The People's Daily, said in a front-page report Tuesday.
Zhou, a member of the party's powerful nine-member Politburo Standing Committee, visited hard-hit regions for five days, according to the reports.
While there have been no reports of major unrest, refugees have rioted on at least one occasion over misused aid. Parents of children killed in schools have demanded officials answer for alleged corruption in the buildings' construction.
At least 15 Sichuan officials have also been removed from their posts for mishandling relief work. Another 13 have been given other forms of administrative punishment.
The government promised to carry out earthquake-resistance checks of all school buildings nationwide before Sept. 1, the beginning of the new school semester, Xinhua said.
Brick school buildings built before 2001 would get extra attention in the exam, according to the notice by the ministries of education and housing. Every dormitory, cafeteria and public bathroom, from the kindergarten level through university-level, would also be checked, it said. Any building found to be potentially dangerous would be banned.
Officials and people found to be accountable for quality accidents regarding school facilities will be dealt with harshly according to law, the notice said.