By Mary Wisniewski

WASHINGTON, Ill., Nov 18 (Reuters) - When a powerful tornado bore down on the small city of Washington, Illinois, on Sunday, Ryan Bowers took his wife's advice and sheltered in the basement with their 2-1/2-month-old daughter and their dogs.

Winds of up to 200 miles per hour leveled their home, along with a large swath of the city of 15,000 people east of Peoria, but the Bowers survived, as did almost all of their neighbors.

The twister, part of a fast-moving storm that hammered much of the Midwest, killed eight people in Illinois and Michigan, but many survived thanks to quick reactions like Bowers's and because their homes had basements to flee to.

"I have to believe that 90 percent of those people who survived were probably in their basement, taking cover, or at church," said Washington Mayor Gary Manier, who noted that he was among the many town residents who were in church when they heard warning sirens.

"We thank God that our community listened and took heed," Manier said, standing in a destroyed section of Washington where bits of American flags and insulation from destroyed houses clung to trees that had been stripped of their branches and remaining leaves by the storm.

Bowers, 33, said he normally disregarded tornado warnings but headed to his basement after seeing the debris cloud barreling toward his house.

"I ran back inside, ran in the basement, not 15 seconds later our basement windows were sucked in and everything was twirling about," said Bowers. "Everything was white and all I could hear was snapping ... Things were dropping on top of me and splitting in two."

He and his wife Andrea, 32, briefly returned on Monday to retrieve a family Bible and a pink baby rattle that was their daughter Sydney's favorite toy.

UP TO 500 HOMES DAMAGED

Manier estimated that 250 to 500 homes had been damaged by the tornado, rated as the second-most powerful magnitude of twister, which hit the city east of Peoria with winds of 166 to 200 miles per hour (267-322 km per hour).

In the destroyed area, where buildings were reduced to rubble and cars turned upside down, authorities barred vehicle traffic out of concern that people could be injured while attempting to retrieve their possessions.

But people came anyway, on bicycles and on foot, to sort through their belongings and help their neighbors.

"It's crazy, you walk through a town you've lived in your whole life and you don't even know where you're at," said Tanner Smith, a 17-year-old wide receiver who was among about 30 members of the Washington Community High School football team, the Panthers, who came to help with relief efforts.