PORTLAND, Ore. — The massive horseshoe-shaped Celilo Falls were submerged by a reservoir after The Dalles Dam was built in 1957 — this much is true.

But the belief that government demolition teams blasted the falls and destroyed them? Not true, according to sonar maps released by the U.S. Army Corps of Engineers.

Others thought the falls might have been silted over by the river in the years since the dam was built.

The maps show that the falls, located about 10 miles upstream from The Dalles, are intact beneath the Columbia River’s surface. The main cataract of the falls stands out in a sonar image of the river bottom.

“The rumor was that the U.S. Army Corps of Engineers had in fact blown it all up,” said Elizabeth Woody, a writer and member of the Confederated Tribes of Warm Springs. “I actually cried, I was so relieved that it wasn’t destroyed.”

Those living in the village at Celilo Falls heard and felt blasts set off for excavations at the dam, Woody said, and believed the government had used dynamite to demolish the falls.

“People said the Corps had dynamited Celilo so no one would fight for the dams to come down,” Woody said.

In the years since the dam was built, a debate has surfaced over the removal of the declining hydropower dams.

Col. Thomas O’Donovan, the Corps of Engineers’ Portland district commander who is now serving in Afghanistan, decided to look into the controversy.

Finding that records did not turn up any evidence that the Corps of Engineers had demolished the falls, he asked for a detailed sonar survey of the area in April 2007, said Dan Proudfit, who heads the Corps of Engineers’ survey section.

O’Donovan’s team cruised the surface in a boat equipped with a multi-beam sonar scanner, which bounces sound beams off the river bottom to create images of its contours.

For thousands of years the falls were a fishing site for American Indians and their ancestors. They also were the center of a major tribal trade network that brought traders from tribes as far away as the Midwest and Southern California.

Stone Age tools and salmon bones unearthed by archaeologists show that people fished at Celilo Falls more than 10,000 years ago.

Louie Pitt Jr., a Warm Springs tribal member, was 6 when the dam was built. Before the falls were submerged by the reservoir, he said, his family made a living by selling the salmon caught there.

He remembers singing, dancing and playing near the falls, and believes his tribe and others in the area will see the Celilo Falls again.

“Someday those dams will be gone,” Pitt said. “When that day comes, the falls will return. Indians will be waiting.”