Riley Strain's shocking final hours are revealed in new police report two months after student vanished during boozy night out in Nashville and turned up dead in river

Tragic student Riley Strain downed up to 15 alcoholic drinks on the night he vanished, a police investigation has found.

A new report into 22 year-old Strain's drowning in Nashville's Cumberland River in March began drinking on a bus into Nashville's bars with his Delta Chi fraternity brothers.

He did so even though the driver had warned the University of Missouri students that boozing was banned. 

One of Strain's frat brothers said he downed at least two vodka shots and three IPA beers on the bus, WSMV reported. 

Arriving in Nashville at 4:30pm on March 8, Strain was seen drinking a margarita within 30 minutes.

An examination of footage from downtown Nashville bars showed that Strain was served alcohol three more times over the course of the evening. 

That puts the late student at around nine drinks, with Nashville Metropolitan Police not disclosing where they believe the remaining three drinks were consumed. 

Strain's disappearance became a huge story, with his body found in the river two weeks later. Eerie footage showed him walking unimpeded during his final journey, with the drowning ruled accidental. 

In June, autopsy reports showed that Strain died from alcohol poisoning and drowning. His blood alcohol level was .228 - which is three times the legal limit.

The college student's body also had traces of Delta 9, a form of THC which is legal and readily available in Tennessee.  

Videos of Strain that had been recorded earlier in the night shows him able to stand and speak comfortably. 

But at around 8.40pm, he began to stumble repeatedly and started showing signs of intoxication. 

At around 9.28pm, staff members at Luke 32′s Bridge escorted Strain out their bar after he got into an argument. 

The bar had previously said that it had only sold Strain one alcoholic drink before asking him to leave.

According to Tennessee Alcohol Beverage Commission investigators, despite the teen being thrown out the bar, fraternity members continued on with the party.

One of the fraternity brothers later told police that he tried to contact Strain by phone at 9:47 but all her heard was the deceased speaking with a slurred speech.

During the call, the now completely-intoxicated Strain indicated that he was on his way back to the hotel. 

But at around 1am, his frat brothers discovered that the he was not in his room or answering his phone.

According to 911 call records,  the group did not report him missing to police until 1.46pm - over 12 hours after they found he was missing. 

Chilling footage collected by police from Downtown Smoke & Vape Shop on Church Street showed Strain near the intersection of 2nd Avenue and Church Street. 

The seemingly intoxicated student was wearing a two-toned black and brown shirt and blue jeans and took a tumble, then quickly got back up and continued down the street.

Another camera caught near the intersection of Gay Street and 1st Avenue North just before 10pm taking large strides with his head down as he stumbled through the streets.

The student had reportedly FaceTimed his mom Michelle Whiteid that evening, and she said nothing seemed out of the ordinary.

A spokesman for the University of Missouri told WMSV that the fraternity formal was a private Delta Chi event and confirmed that the fraternity has no outstanding student/organization conduct violations.

David Easlick, an attorney who sues fraternities after the death or injuries of students said:  'For the school to sit there and say they're in good standing, that's morally offensive. After what happened to that kid?

'All (fraternities) stuff for parents, how they have risk management, they condemn alcohol abuse, it's baloney,' Easlick said.