"I work in shifts, sometimes from midnight until afternoon of the next day, which is intense," Yang said. "But I know it's for our own good."

So far, soldiers have been able to stopper all the seepage points the inspectors have found.

"The situation now is fine, but we have to stay alert," Yang said.

All hands on deck

Residents elsewhere are joining the flood control campaign.

In Jiangxi's Furong Farm Town, locals have volunteered to help with inspections, putting up alert signs and delivering food and water to soldiers.

"My son is about their age and it breaks my heart to see them working non-stop in heavy downpours and scorching heat," said a villager surnamed Wang. "But I know this is a special period and I hope they can take care of themselves while working."

Chinese authorities are sparing no effort in battling the floods.

This week, Premier Li Keqiang said China should prepare for an arduous campaign against floods as July-August is "a key period for flood control."

The People's Liberation Army and armed police will send more troops to disaster-hit areas on the direct orders of President Xi Jinping.

Meanwhile, local governments have urged migrant workers in big cities to come back to help bail out their hometowns, as most of those living in China's rural areas are the elderly and the young.

But more tests are on the way. Typhoon Nepartak is whirling toward the mainland and is forecast to bring strong winds and downpours to many parts of China, including Jiangxi.

As the sun set, soldiers around Fanghu Lake sat down and had simple meals on the embankment while still in their uniforms and muddy shoes.

"We are facing a tough battle," APHF soldier Liu Qing said as he wiped sweat from his forehead. "But I believe we will make it through."