Bangkok, Thailand (CNN) -- The death toll from the worst floods in half a century to hit Thailand continues to rise.
By early Sunday morning, the number stood at 297 from two months of lashing rain, with more than 8.5 million in 61 provinces affected by the rising waters, authorities said.
More rain was predicted for Sunday in some provinces and in the capital city, Bangkok.
In the ancient city of Ayutthara, one of the worst-hit regions, military trucks moved slowly down the main street, cutting through a constant river of water, passing out aid to those who can get close.
Anyone with a boat used it to transport aid or to help neighbors carry their possessions from flooded houses. Others used rubber tires of slabs of Styrofoam.
In Bangkok, crews worked feverishly, widening canals and strengthening flood barriers to protect the city.
"I have to say here that there is a lot of water coming to Bangkok but the situation not critical yet," said Bangkok Governor Sukhumbhand Paribatra.
The Bangkok suburb of Sam Kok is sandwiched between the overflowing Chao Phraya River and the 2.5-meter floodwalls that are so far successfully protecting the inner and commercial part of the capital. The water here has nowhere to go and levels are rising fast.
"In one or two days (flood waters) will pass through Bangkok, but the fact is that the impact of such flow would be less if the water was allowed to pass through, rather than concentrated in one area," the Flood Relief Operations Command said Sunday.
Floods are an annual occurrence in the country but it has been particularly acute this year.
Thais across the country are donating food, water and clothing to help the worst-hit areas. Authorities said donations have far surpassed previous years.
The government said that it has received $2.07 million in donations, including from other countries, by Sunday. The United States said it is sending 26 helicopters to help the relief effort, invaluable as more roads turn to rivers and become impassable.
United Nations agencies also are on standby, while the activating the World Health Organization has offered emergency health kits.
CNN's Paula Hancocks and Kocha Olarn contributed to this report.