WILLOWS -- Officials classified the Labor Day weekend drowning death of Lafayette man Brett Olson as accidental and closed the case Tuesday.
Olson, 20, went missing from beer can beach during the weekend float Sept. 2 on the Sacramento River. A fisherman found his body a week later about a mile or two downstream.
The Glenn County Sheriff's Office received autopsy results Monday, Undersheriff Rich Warren said Tuesday. The doctor who performed the autopsy of Olson's body determined that he drowned, had alcohol in his system and had recently used cocaine.
Olson's blood alcohol content was 0.28 percent, however alcohol levels can increase by about 0.05 after death, Warren said. When Olson went under the water, his blood alcohol was about 0.23 percent, almost three times the legal driving limit.
The Cal Poly San Luis Obispo student came to Chico to visit friends and to tube the river. About 10,000 other people floated from Irvine Finch River Access to Scotty's Landing on the Sacramento River that Sunday. No other people were reported missing or dead.
Olson's body had no signs of trauma and all evidence indicated he drowned that day accidentally, Warren said.
Olson grew up in Lafayette and was a 2010 graduate of Acalanes High School.
The Glenn County sheriff and undersheriff gave Olson's parents the autopsy results at 2 p.m. Tuesday in Fairfield.
"I just can't begin to comprehend what they're going through," Warren said. "I don't know how any parent could go through that."
Search and rescue teams from Glenn and Butte counties, along with tracking dogs and cadaver dogs, looked on the river and in the thick brush along the water for signs of Olson.
"Any time we're doing a search, we're under the belief the person is OK and there's something we can do for them because there's always that slim opportunity and we don't want to waste it if we have it," Warren said.
Olson's family members, friends and many college-aged volunteers canvassed Chico following his disappearance in an effort to get information on the young man's whereabouts. His parents thought, and hoped, he could be hiding somewhere in Chico.
In Warren's 25 years of service, he doesn't remember any other drownings during the Labor Day weekend float, he said. One year during the summer, a tuber hit a snag and went under water, but medics revived him.
The sheriff's office is working with other law enforcement agencies, Chico State University officials and other stakeholders in an effort to make the Labor Day weekend more safe, Warren said.
"There are things in life that are inherently dangerous and risky," Warren said. "I don't know if we can ever take all of the risks out of life. We have a certain amount of freedom, with that comes risks."