By Sruthi Gottipati and Jatindra Dash

GANJAM/BHUBANESWAR, India (Reuters) - A mass evacuation saved thousands of people from India's fiercest cyclone in 14 years, but aid workers warned a million would need help after their homes and livelihoods were destroyed.

Cyclone Phailin was expected to dissipate within 36 hours, losing momentum on Sunday as it headed inland after making landfall from the Bay of Bengal, bringing winds of more than 200 kph (125 mph) that ripped apart tens of thousands of thatched huts, mangled power lines and tore down trees.

Authorities in the eastern state of Odisha said the death toll stood at 15 people, all killed as the storm slammed in from the ocean. Most died under falling trees and one was crushed when the walls of her mud hut fell in.

The low number of casualties stands in contrast to the 10,000 killed by Odisha's last big cyclone in 1999.

The building of hundreds of shelters since, warnings which started five days before the storm and mass evacuations - often by force - minimized loss of life, aid officials said.

Almost a million people in Odisha (formerly Orissa) state and adjacent Andhra Pradesh spent the night in shelters, some after wading though surging rivers to higher ground. Others sought safety in schools or temples.

"The loss of life has been contained this time with early information and speedy action of government," said Sandeep Chachra, executive director of ActionAid India.

Indian media commentators were effusive in praise for the evacuation operation and for accurate forecasting by India's Met office. Before the storm, some foreign forecasters had warned that India was underestimating its strength.

Authorities cancelled the holidays of civil servants during the popular Hindu Dussehra festival, deployed disaster response teams with heavy equipment as well as helicopters and boats for rescue and relief operations.

Over the years, organizations like the Red Cross have mobilized thousands of volunteers across the cyclone-prone region, who are not only trained in basic first aid but also help with evacuations and relief distribution.

Drills are organized so people know what to do when an alert is issued, locking up their homes, leaving cattle in safe places and taking only a few clothes and important documents with them.

"The 1999 cyclone was a real wake-up call for India. It was at a time when economic growth was high and India was seen as developing rapidly. It was embarrassing to be seen to be not taking care of their people, even with all this development," said Unni Krishnan, head of disaster response for children's charity Plan International.

The death of at least 89 worshippers at a temple celebrating Dussehra in central India on Sunday was a reminder that disasters with many casualties remain common. In July floods and landslides killed nearly 6,000 people in India's Himalayan foothills.

DESTRUCTION

Phailin left a trail of destruction along the coast, overturning cars and large trucks. Storm surges from the sea submerged farmland near the coast, while heavy rain flooded towns inland.

Along the highway through Ganjam district in Odisha, the countryside was ravaged. An electricity tower lay in a mangled heap, poles were dislodged, lines tangled and power was out in much of the state. In villages, cranes lifted trees off crushed houses.

A barber shop was tilted to one side. The students' common room at Berhampur University was a gaping hole, its facade knocked out by the cyclone.

"The wind was so strong I couldn't get out of here," Gandhi Behera, a cook in a nearby snack shop said.

The Indian Red Cross said its initial assessments showed that over 235,000 mud-and-thatch homes owned by poor fishing and farming communities had been destroyed in Ganjam district alone. It expects thousands of people to need help in coming days.

Plan International said it was concerned about the health and sanitation needs of close to a million people and the impact of the storm on people's livelihoods.

"They cannot stay in the shelters for long as they are overcrowded and sanitation issues will crop up with the spread of diseases such as diarrhea and dysentery, especially amongst young children," Mangla Mohanty, head of the Indian Red Cross in Odisha, said by phone from Ganjam district.

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