BOULDER, Utah -- A 32-year-old father and member of a search and rescue dive team drowned over the weekend while saving his 5- and 7-year-old sons at a lake in Garfield County, deputies said.

Scott Pederson, from St. George, and his family were at the Upper Barker Lake on Boulder Mountain in Garfield County, Utah, on Saturday.

He was in a four-person pedal boat while his sons were swimming in the middle of the lake. According to Garfield County sheriff's spokeswoman Becki Bronson, the two boys started having trouble staying above the water.

The water temperature was said to be in the low 50s, and the boys could not stay afloat, she said.

Pederson "immediately jumped in and kept the boys' heads above water and tried to push them into the boat," Bronson said. Pederson "realized he too was in trouble and yelled to the shore for help from his father-in-law and brother-in-law, who swam out to the pedal boat."

The father-in-law, J.H. Frost, was able to pull the boys back into the pedal boat.

"But as soon as they had done so and turned around, Pederson had slipped below the surface," Bronson said.

The family tried several times to find Pederson in the lake. Bronson said it is about 8 feet deep with murky water and has about 2 to 3 feet of tangly weeds.

A rescue team from Garfield County, Utah, was called to help look for Pederson. They found his body around 6 p.m. Saturday night.

In what Bronson called a "sad twist of irony," the rescue team called to look for Pederson was the same team Pederson had just joined.

Garfield County Sheriff Danny Perkins called Pederson's actions "heroic."

"It is an absolute miracle that no one else drowned, and it was due to the heroic efforts of Mr. Pederson," Perkins said. "We express our deep condolences to his family."

Deputy Kevin Moore said the "water temperature, along with the undergrowth vegetation, caused the drowning of a very strong and skilled swimmer."

"There's no way to know on the surface just how cold, murky and dangerous the water can get."