Mystery of human remains found at Hoover Dam 15 years ago finally solved

William Herman Hietamaki was last seen alive in 1995

William Herman Hietamaki (pictured) was last seen alive back in 1995 (Mohave County Sheriff’s Office’s post/Facebook)

A mystery man whose remains were discovered at the Hoover Dam 15 years ago has finally been named thanks to DNA technology.

The bones – found near the hydroelectric power plant that sits between Nevada and Arizona – were identified as those of William Herman Hietamaki, a Michigan man who was last seen alive in 1995.

It was November 2009 when two roadside workers stumbled across the set of human bones while taking a break from pouring cement along Highway 93, the Mohave County Sheriff’s Office announced on Tuesday.

One of the workers had spotted what appeared to be a human bone sticking out and, when the pair looked further, they found more, the sheriff’s office said.

A search was carried out and “a sun-bleached pair of blue jeans, a damaged white towel, a sun-bleached red t-shirt, a black athletic shoe and a green sleeping bag” were found along with the man’s remains.

But, who the bones belonged to and how and when he had died remained a mystery for years – until now.

Two years ago, the sheriff’s office submitted a bone sample to the Arizona Department of Public Safety lab to obtain a DNA profile that could be submitted to Combined DNA Index System (CODIS). A sample was also sent to the University of North Texas. But, the attempts to identify John Doe failed.

Then, in April 2024, Othram, a genetic testing lab in Texas, announced that a genealogy grant had been obtained to carry out testing in the case.

A sample was then sent to Othram lab and a DNA profile was created which was then uploaded to a genealogy database.

From there, investigators were able to determine that “John Doe was a descendant of ancestors born in the mid-1800’s and residing in Michigan.”

Investigators set about interviewing possible relatives and learned about Hietamaki.

Hietamaki, born in April 1950, had attended high school in Trout Creek, Michigan, and then mechanic’s school before setting off on an adventure around the southwest US.

He had been “known to hitchhike to various locations” adopting a “nomadic lifestyle”, said the sheriff’s office.

Public records show Hietamaki, who went by his middle name Herman, spent some time living in Las Vegas, Nevada.

He was last seen by his family in 1995 after he visited his sister in New Mexico.

Further testing was able to confirm that the remains belonged to Hietamaki.

Investigators have been unable to pinpoint his exact cause and date of death “due to the state of his remains” but estimate he died between 2006 and 2008, when he would have been 56 to 58 years old. Police said he was known to suffer from epileptic seizures.

The MCSO said: “The Mohave County Sheriff’s would like to thank Othram Inc. for their work in this case and for obtaining grant funding to enable the forensic genetic genealogy investigation to be completed.

“Hietamaki’s family now has closure due to their dedication in identifying John and Jane Does.”