The incident began around 11 a.m. Thursday when the woman apparently lost control and crashed her motorcycle into the side railing of the Lake Washington Blvd. overpass near the west end of Lake Washington.

The impact sent her off the ramp and into the lake.

"So we're thinking that's weird a crashed motorcycle half in the street and nobody around," said witness Charles Hatley. "We looked around first and didn't see anybody then we looked over the rail we saw a helmet floating way out in the water so we thought 'oh gosh, the person is in the water.' It was a pretty good distance, probably about 40 feet down to the water."

Somehow, the woman managed to swim the 30 or so yards to a nearby marsh, where she waited for rescuers to reach her.

"The only thing that she did was roll over and give us a slight wave," Hatley said.

Rescuers had to get to the island, then hack a path through dense brush to reach her.

"It was amazing the recovery and the rescue was awesome," said witness Sandy Swafield.

Medics managed to get the woman onto a backboard, then carried her back along a little walkway that connected back to the mainland where she was taken by ambulance to Harborview. Due to privacy laws, the extend of her injuries are not known, but witnesses said she was conscious when being loaded into the ambulance.

Police are still investigating the cause of the accident. But the State Patrol says there were no skid marks and that excessive speed was a possible factor.