Human remains found near Hoover Dam in 2009. Identified as “nomadic” male. Last seen by family in 1995.

The remains of William Herman Hietamaki were ultimately identified, although authorities were unable to determine his cause of death

Mohave County Sheriff's Office/Facebook William Herman Hietamaki, whose remains were found in 2009, almost 15 years after his disappearance. — Mohave County Sheriff’s Office/Facebook

William Herman Hietamaka, whose remains were found in 2009, almost 15 years after his disappearance.

Arizona authorities say human remains found at the Hoover Dam in 2009 belong to a man who was last seen in 1995.

William Herman Hietamaki was last seen by his family in 1995, “when he visited his sister in New Mexico,” according to a press release. Mohave County Sheriff’s Office.

Hietamaki, using his middle name, “was known to hitchhike to various places and led a nomadic lifestyle.” Public records show that he actually once lived in Las Vegas and suffered from epileptic seizures.

More than a decade later on November 11, 2009, the remains were discovered by workers employed to pour cement for a project on Highway 93 near Hoover Dam. However, over the years, even as detectives continued to investigate “for leads,” all attempts to identify John Doe were unsuccessful.

In February 2022, an MCSO detective sent a bone sample obtained from the medical examiner’s office to an Arizona lab requesting a DNA profile. At the same time, another sample was submitted to the University of North Texas. However, these attempts also ended in failure.

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Two years later, things began to change when investigators assigned to MCSO’s Special Investigations Unit (SIU) learned that they had “received funds to pay for forensic genetic genealogy (FGG) on this case.”

The UNT sample was then “sent to the Othram lab,” where “a DNA profile was created and uploaded to a genealogy database.”

Earlier this month, investigators received a report indicating that John Doe “was a descendant of ancestors born in the mid-19th century and residing in Michigan.”

After investigating possible relatives, investigators learned that Hietamaki, the brother of one of the siblings they interviewed, had not been seen by the family since 1995.

“Reference testing conducted on these relatives confirmed that the unidentified remains of John Doe were Hietamaki,” police added.

The sheriff’s office said the medical examiner was unable to determine Hietamaki’s cause of death “due to the condition of his remains.”

According to the police, however, it appears that he died between 2006 and 2008.

“The Mohave County Sheriff would like to thank Othram Inc. for their work on this case and for obtaining a grant to complete a forensic genetic genealogy investigation,” the sheriff’s office said in its news release. “Hietamaki’s family has been locked up because of their sacrifice.”