Published: Nov 10, 2011 6:54 PM EST

BANGKOK (AP) - Sahattaya Vitayakaseat placed a tiny crown-shaped boat made from curled banana leaves and marigold flowers into the murky brown water and let it drift toward a park bench submerged by Bangkok's surging Chao Phraya river.
    
She then closed her eyes and prayed, silently begging forgiveness from Thailand's goddess of water - who some believe is responsible for a three-month wave of cataclysmic flooding that has killed more than 500 people.
    
"I hadn't planned to come out tonight because there's been so much loss and so much grief," Sahattaya, 45, said Thursday as the Southeast Asian kingdom celebrated Loy Krathong, a full-moon festival held every year when the rainy season comes to an end. "But this is a chance to let our misery float away."
    
Thais believe the candlelit boats launched during the Loy Krathong holiday can carry misfortune away with them, allowing life to begin anew. But this year the tradition, begun hundreds of years ago to pay tribute to water itself, has taken on a profound new irony.
    
Floodwaters born from months of intense monsoon rains have swept the country, engulfing whole cities in one of the worst natural disasters in modern Thai history. In the last few weeks, areas of outer Bangkok have also been submerged, forcing residents to flee neighborhoods where the best way to get around now is on boats made from anything that can float - plastic foam, empty water bottles, bamboo poles.
    
The threat is not yet over, and the Tourism Authority of Thailand responded by canceling all official Loy Krathong celebrations in the capital this year.
    
The Chao Phraya river - normally filled with tens of thousands of floating lanterns during the holiday - was dark and mostly empty Thursday night.
    
The Bangkok Metropolitan Authority had urged people not to float krathongs on the river or in any flooded zones. Officials are worried they cold trigger fires in abandoned homes or clog drains and canals critical to helping ease the massive pools of runoff bearing down on the metropolis of 9 million people.
    
Still, hoards of smiling Thais came out to celebrate, packing parks across Bangkok where festive vendors sold boiling noodles, balloons and krathongs made of ice cream cones. One hint that things were different this time: donation boxes set up to help flood victims.
    
At the riverside Santi Chai Prakan Park, teenagers set off firecrackers. A dozen candlelit paper lanterns floated into the night sky above a floodlit fort.
    
Revelers set loose hundreds of krathongs on the water, in a spot where the overflowing river had submerged a set of park steps. The krathongs were kept from the river, contained in a barricaded zone beside it.
    
"She's cruel," Vilasini Rienpracha said with a lighthearted laugh, referring to the Thai water deity called Phra Mae Khongkha. "She wanted to come into our streets and to see what the city is like. But we've had enough, it's time for her to go."
    
Loy Krathong has its roots in an era when most Thais lived in stilt houses made of wood, dependent on rivers and rain-fed agricultural land for their sustenance and survival.
    
That life is being erased by modern development, which critics say has exacerbated the current crisis. Over the last few decades, canals that once allowed annual floodwaters to pass through the capital unimpeded have been paved over to make room for roads, highways, shopping malls and housing estates.
    
Sahattaya said Thais have treated the nation's rivers poorly, polluting them with garbage, and exacerbated annual floods with deforestation and poor urban planning.
    
"If we as humans don't change our behavior, more catastrophes will come," she said. "It's time to start doing something positive instead of destroying the environment. We've been greedy. We've treated Mother Nature poorly. And now she's come back to hurt us."

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