OCCOQUAN -- What Madeline Bell remembers best about the surge of muddy water that engulfed and forever changed this historic town 20 years ago is the sound.

"It was raining, beating so hard and we were all soaked. The rain just kept coming and coming. We could hear it night after night, coming harder," said Bell, who has lived all of her 72 years here.

"Then they said we had to leave because the hurricane was coming. A lot of people couldn't believe it could happen. And they sure couldn't believe what happened after it was over."

Hurricane Agnes dumped 14 inches of rain on the town in 24 hours. Millions of gallons of rainwater poured into the already swollen Occoquan River, pushing it 20 feet or more out of its banks and over the top of a dam above the town of about 200.

"There had been a drought earlier that year and the dam operators were reluctant to open it," said LaVerne O. Carson, the town's mayor. "They wanted to fill the reservoir because it was so low. They waited until it was too late. Water came over the top and there was no way to control it then."

"Also it was a full moon, and this is a tidal river that is affected by the moon. So we had flood waters coming down from above and the tide pushing in from below. Plus we're in a valley here, and flash floods came right down into town," she said. "We caught it from all sides, basically."

The roiling water claimed the town's 94-year-old one-lane iron bridge on June 22, 1972, then ripped the backs off a dozen homes and buildings nearest the river the following day.

When Bell and her family returned to Occoquan after three nights at a firehouse, the entire main street of the more than 200-year-old mill town was flooded. Boats and empty coffins from a damaged funeral home floated down the street or jutted wildly from buildings.

"There was a boat right through the front window of the post office," Bell said.

"Agnes was a very slow-moving tropical storm, not a hurricane when it reached Virginia. It stalled and dumped rain on Virginia for 36 hours," said David W. Moody, a chief hydrologist at the U.S. Geological Survey in Reston.

The storm followed two weeks of heavy rain that had left the ground soaked.

"The rain couldn't go anywhere" and began to run off into streams and rivers, he said.

Hurricane Agnes and the floods it produced killed 117 people in 12 states and caused an estimated $3.1 billion in damage.

In Virginia, the death toll was 13 and the damage bill about $325 million. Occoquan suffered about $2.5 million in damage, making it among the hardest-hit communities. No one was killed in the town, but three men died in flooding elsewhere in Prince William County.

Statewide, about 1,400 homes were damaged or destroyed, along with an unknown number of roads and bridges.

The floods did more damage over wide areas in rural counties near Charlottesville and in the Shenandoah Valley, where entire houses and barns washed downstream in flash flooding. And in Richmond, water, sewage and power plants were flooded. The downtown area was closed, as were four of the five bridges spanning the James River.

But in Occoquan, Agnes's effects were concentrated and its aftermath marked the town's growth from a typical Southern riverside town into a thriving tourist attraction.

Many families sold their damaged homes rather than pay to restore them. Few if any residents carried flood insurance. The buildings were rebuilt as shops and restaurants, and many families who had lived in the town for decades moved away.

"I can count eight families who are still here" from the time of the flood, Bell said. "The old people are dead and gone and they've taken those houses and made them into shops. Hardly anybody lives downtown anymore."

The town had about 300 people and 145 businesses at last count. Most of the buildings on the town's five-block main street are occupied by small craft and antique shops or restaurants. There still is a a marina, but no other large commercial operation.

In one of the few visible signs of the flood, a beam 10 feet off the ground is frayed and battered where a boat pounded the side of one building.

"I'm not saying the flood was a good thing, but it did more to revitalize the town than it did to destroy it," said Bob Porter, who runs a doll shop on the main street.