Authorities are set to drain stagnant water by the end of the month which continues to submerge part of a remote mountainous town in northwest China's Gansu Province. This comes three weeks after a devastating mudslide left more than 1,700 people dead or missing, a senior military official said Friday.

For weeks, soldiers and work crews have been using explosives and excavators to remove the massive debris and rocks that were swept down by the mudslide into the waterway and formed a barrier lake, flooding the riverside areas of Chengguan Township, Zhouqu County.

People's Liberation Army Deputy Chief of Staff Zhang Qinsheng, who also serves as the deputy head of the work group for Zhouqu relief under the State Council, announced Friday that the deadline for removing stagnant water is 12 p.m. August 30, and rescue crews are working hard to meet the deadline.

Experts have warned that the stagnant water -- at some point rising high enough to completely submerge a street light pole -- would rot the foundations of 80 flooded buildings and caused them to collapse. The water also posed a serious threat to public health, as it was an easy breeding ground for mosquitoes and bacteria.

Meanwhile, the government of Zhouqu on Friday ordered the sludge-covered area of the mudslide to be sealed off for both safety and health reasons.

This came five days after authorities banned the recovery of bodies in the hard-hit area -- about five kilometers long and 300 to 500 meters wide, at the foot of Sanyanyu Mountain.

An avalanche of rocks and mud roared down the Sanyanyu mountain slope at midnight on Aug. 7, leaving 1,456 dead and 309 missing as of Aug. 27. The bodies of the missing, along with an undetermined number of animals, were believed to be buried under the meters-deep sludge.

Soldiers have dug a water channel in the sludge-covered area to direct waters into the Bailong River. The mud and debris were carried away and dumped at farmlands outside the town properof Zhouqu. However, they might be stopped from continuing and leave the devastated hard-hit area untouched. Authorities are looking for new areas to settle homeless residents who are now housed in disaster relief tents.

"No dumping sites can be found for the sludge if the clearing efforts continue. Also, the site sits in an area where mudslides frequently occur. It is not suitable for reconstruction," said a directive issued by the Zhouqu county government. Before the disaster, the county seat, hit by the mudslide, had about 45,000 residents. Nearly half of them lost their homes in the disaster.