The dike breach along Dongting Lake in a township in Hunan province is expected to be sealed off by noon on Tuesday, according to local authorities.
As of 3 pm on Sunday, a gap of 87.3 meters had been plugged, with first responders continuing to make efforts to repair the 220-meter breach in the dike in Tuanzhou township of Huarong county in the city of Yueyang, local authorities said at a news conference.
After the breach occurred at around 5:48 pm on Friday, President Xi Jinping urged all-out rescue and relief efforts to safeguard people's lives and property. He instructed that people in threatened areas be evacuated in a timely manner and properly resettled.
A similar breach had taken place in the township in July 1996.
Efforts to plug the dike breach started on Saturday afternoon, after the water level in the lake went down.
Zhang Yingchun, executive deputy governor of Hunan province, said that emergency responders were racing against time to seal off the breach.
With trucks and barges bringing rocks and raw materials, they can proceed to rebuild 60 to 80 meters of the dike each day. A total of 100,000 cubic meters of rock is needed to plug the whole gap, she said.
More than 4,200 emergency responders and over 3,000 pieces of equipment are assisting in the relief and rescue efforts, she added.
The central government has allocated 258 million yuan ($35.5 million) and the provincial government 250 million yuan for emergency flood response in Hunan, Zhang said.
The embankment, viewed as "the second line of defense", is located about 2 kilometers from the breached dike and is 14.3 kilometers long, according to Xinhua News Agency.
An area of 47.64 square kilometers, which is about 92 percent of the township's total area, is underwater, with the average depth of water being 5 meters, according to local newspaper Hunan Daily.
The Ministry of Water Resources has sent an expert team to offer technical support to local teams.
Li Heng, leader of the expert team, said the most important work is to reinforce the embankment, which separates the flooded township from other areas. All 7,680 residents of the township have been evacuated and resettled, and there were no immediate reports of casualties or injuries, she said.
Zhu Dongtie, head of Hunan's Department of Water Resources, said they need to drain about 200 million cubic meters of water and plan to use pumping equipment as soon as the breach is repaired.
A total of 3,224 residents have been resettled at four schools in Huarong county.
Xiao Juxiang, 68, said she and her husband left their home after hearing an evacuation announcement on the village radio.
"The atmosphere was very intense and I was very nervous," she said, emphasizing that she felt reassured after seeing People's Armed Police Force personnel join the rescue efforts.
The troops transferred all villagers to safe locations and gave them water and food, Xiao said, adding, "You could see how tired they were. It is no mean task to evacuate so many people."