Chinese rescuers Monday finished draining the stagnant water in the barrier lake that formed after a mudslide blocked a river in Zhouqu County in northwest China's Gansu Province 23 days ago.

The water level of the Bailong River had returned to its normal level after the barrier lake had been drained, Chinese People's Liberation Army Deputy Chief of the General Staff Zhang Qinsheng told journalists in Zhouqu Monday afternoon.

The barrier lake had flooded the riverside areas of Chengguan Township, Zhouqu County.

Minister of Water Resources Chen Lei said 1.5 million cubic meters of mudslide debris had blocked a 1.2 kilometer-long section of the river, raising the river water level by 10 meters.

As the water retreated Monday, workers began spraying the previously-submerged areas with disinfectant.

At Guanba Street, one of the low-lying areas in Zhouqu, local residents joined soldiers to clear debris and mud, which is still 20 centimeters deep in some areas.

Provincial construction safety official Yang Fubo said 205 buildings that were inundated with mud and sludge need to be checked for safety.

Some of the buildings may need to be demolished before they are rebuilt, he added.

The avalanche of rocks and mud on Aug. 8 left 1,700 Zhouqu residents dead or missing.