Scott Pederson was an "amazing" swimmer, rescue diver, surfer, wakeboarder and wakesurfer, said his wife, Shaunna.

But most of all, she said, he was a loving father.

The last time Shaunna saw her husband, he was grasping his children, holding their heads just above the frigid waters on Garfield County's Boulder Mountain. In the end, Scott gave his life for Noah, 4, and Gabe, 7.

The boys were swimming in the Upper Barker Lake at 11 a.m. Saturday as their dad rode a pedal boat. Pederson, 32, noticed the boys began to struggle to stay afloat in the 54-degree water. He jumped in and tried to push his sons into the boat. But he, too soon needed help and called out for his father-in-law and brother-in-law.

The men swam out to the boat and pulled the boys out of the water, but when they turned for Scott, he had disappeared in what Shaunna estimated was as water 14 feet deep. Sheriff's deputies said the water was murky and tangled with weeds.

Meanwhile, Noah had stopped breathing, and even after a few minutes in the lake, Shaunna's father and brother were so cold "they could hardly walk," she said.

St. George and Washington County search and rescue dive team found Scott's body several hours later.

Garfield County Deputy Kevin Moore said mountain lake water may not seem cold on the surface, but temperatures quickly plummet.

"Tragically in this case the water temperature, along with the undergrowth vegetation, caused the drowning of a very strong and skilled swimmer," Moore said in a news release.

On Monday, Noah and his brother were at home in St. George doing OK with the rest of the family.

"We're hangin' in there," said Shaunna Pederson.

Shaunna described her late husband as "fun loving," adding that he did great impressions, always wore a smile and constantly wanted to make people laugh.

He was involved in community theater and acted in performances such as "The Crucible" and "Pirates of Penzance." He was practicing for an upcoming performance of "Almost Maine."

Scott served an LDS mission in Oslo, Norway, and worked as an X-ray technician during his six years in the Army. He was stationed in Texas and North Carolina before spending more than a year in Korea.

When the family moved to St. George three years ago, Scott began working for Intermountain Health Care as an MRI technician.

The Pedersons' bishop, Kevin Leany, said the Pedersons worked as primary teachers and activity directors. Leany said Scott also was involved in the Elder's Quorum presidency and was an all-around "great father and great husband."

Scott also recently had finished training to become a certified rescue diver.

"He was an amazing swimmer," Shaunna Pederson said, adding that Scott was on his high school swim team, grew up surfing in Florida and still swam laps once a week for 45 minutes straight.

Said Shaunna Pederson: "That's why this all was such a shock."

Garfield County Sheriff Danny Perkins said the father's heroic efforts made it "an absolute miracle that no one else drowned."