The body of Lucius Robbi, 21, was found in his Subaru at the bottom of a 60-foot embankment near Stanley Lake, the Custer County Sheriff's Department reported. The car was hidden by the trees, but on Thursday searchers in a private helicopter saw the tip of a kayak.
Robbi, a resident of Orleans, Calif., had been spending the summer as a river guide in Horseshoe Bend, Idaho. He was last seen Aug. 19.
In a release, the sheriff's office said the search was complicated by heavy rain that washed away tire marks where Robbi skidded off the highway. Police and volunteers had been searching along several possible routes for any sign of Robbi or his car.
Tina Glaessner, Robbi's mother, using a Facebook page set up after he disappeared, thanked friends who had joined the search.
"We are touched as well by the support of so many who did not even know our family, but showed their humanity and tremendous generosity at such a difficult time through countless acts of kindness," she said.