COEUR d’ALENE — In his five years with the Kootenai County Sheriff’s Office, Deputy Tanner Cox has probably carried out routine night patrols at the Honeysuckle boat launch on Hayden Lake more than 100 times.

Nothing much ever happened.

Until about 10 p.m. Thursday.

Cox was at the security check when he saw a truck slowly rolling through the parking lot heading toward the boat launch.

“It all the sudden started to pick up speed and went straight into the lake, which I didn't believe actually happened at first,” Cox said.

His actions that followed, and those of two other KCSO deputies, are credited with saving the life of the 91-year-old driver.

All three men jumped into the dark, icy water as the truck drifted deeper.

“In that situation, it’s extremely dangerous,” said KCSO Sgt. Justin Arts, who has experience in cold water rescues.

The water was 37 degrees and the air temperature was 21.

Arts said Friday that with "100%" certainty the man would have died without the response of the deputies.

“Had they not been there, I believe with my whole heart that would have been the case," he said. "But because they were there, he’s with his family today.”

Cox said he expected a vehicle to actually go into the water.

"And then it did right in front of me,” he said during a press conference. “So it caught me off guard and I had to almost double take at first to make sure that it was a vehicle that went into the water.”

Cox called for backup and ran to the truck, reaching it within seconds.

The elderly man behind the wheel seemed to be in shock and had a dazed look on his face, he said.

“He wasn't responding to my commands to open the window or open the door,” Cox said.

When the man took his foot off the brake, the truck rolled further into the water.

“I was just trying to keep his attention on me so that he wouldn't take his foot off the brake,” Cox said.

A minute later deputies Cody Ragan and Zach Perry arrived. They had to act quickly, as the truck was nearing the point where the ramp drops off into deeper water.

“I could see that Deputy Cox was trying to get verbal communication with him and there was just no response,” Ragan said.

He climbed into the bed of the truck.

"As I got into the truck and opened the door, the truck was actually starting to go deeper into the water and submerge," Ragan said. "So at that point, he didn't have an option and he was coming out."

Ragan grabbed the man and pulled him free. But the water was too deep for him to stand.

“He couldn't touch where he was at," Ragan said.

Ragan pushed the man to about the midpoint of the truck bed when Perry grabbed him.

“I just received him and started pulling him back in,” Perry said.

All three deputies brought the man to shore, who still seemed to be confused.

“He didn't really want to stand up so we had to carry him all the way back to the shoreline,” Perry said.

The man, a Coeur d'Alene resident, was transported to Kootenai Health where he was treated for hypothermia and was recovering, according to the KCSO.

"The investigation determined that alcohol was not a factor and that the male was just confused and lost," a press release said.

Arts said the deputies acted courageously under pressure.

“As it got more dangerous, that's when they jumped into action, not that it wasn't dangerous to begin with,” Arts said. “But as the truck started to roll away, the window to save him got shorter, they all jumped in."

Hayden Mayor Steve Griffitts thanked the deputies and said the man “would not have made it without your assistance.

“On behalf of the citizens of Hayden, on behalf of their family, and others, I’m glad you made it home safely,” he said “And I’m glad you brought him back safely. So thank you very, very much. More than you’ll know."