HUE, Vietnam (AP) -- Waters receded Monday after Vietnam's worst flooding in a century, but many outlying areas remained isolated and more than 1 million people were hungry and thirsty.

The confirmed death toll climbed to 512, with 307 of the fatalities in worst-hit Thua Thien Hue province.The central committee for flood and storm control said 1 million people were hungry and needed emergency food. All available military personnel were involved in the country's biggest relief operation, with thousands of tons of emergency food en route to the region. Supplies brought into the ancient capital of Hue by plane and helicopter were being delivered as fast as they arrived.

Bottled water became a priority, too. People who had been able to survive on rainwater were running out after the tropical depression dumped a record seven feet of rain on some areas.

Carpenters were working to meet the demand for coffins for areas dry enough to bury victims, including a family of eight found Saturday, their bodies tied together.

"They realized they could not survive the flooding, so they just tied themselves together in hopes that their bodies could be recovered more easily," said Phan Thanh Hung of the provincial flood and storm control center.

Floodwaters disappeared from National Highway 1, the country's two-lane lifeline.