PROVO -- A 17-year-old Heber City boy died in Deer Creek Reservoir late Wednesday morning, the Wasatch County Sheriff's Office reports.

Deputy Sheriff John Rogers said that the body of Kalem Franco was recovered at 12:48 p.m. Franco already was dead when authorities found him, Rogers reported. Rogers said the boy likely drowned, but added that authorities would perform an autopsy in the next few days to determine an official cause of death.

Rogers said that witnesses reported seeing a 17-year-old boy trying to swim from an island in the reservoir to the shore around 11 a.m. The witnesses reportedly saw the boy struggle, then go under the water. Someone threw him a life preserver, Rogers said, but the boy apparently was unable to grab it.

Rogers said the sheriff's office arrived around 11:30 a.m. and deployed divers to search the reservoir. Authorities also searched the reservoir's banks, but Franco's body eventually was located in the water.

Rogers did not know why Franco was swimming in the reservoir or what caused him to struggle. But he said that the water is cold and probably around 53 degrees.

"A really good swimmer would struggle swimming very far in that water," Rogers said.

Franco's death adds to the already record-breaking number of water-related fatalities in Utah this year. Earlier Utah County victims include a 2-year-old boy who died in May after falling into Starvation Creek, a 4-year-old boy who drowned in Utah Lake in April and an 8-year-old boy who drowned in American Fork River in June. U.S. Forest Service spokeswoman Loyal Clark said that Utah streams and rivers are extremely dangerous because of a high snow pack.

"A lot of the rivers and steams are flowing very fast," she said.

Clark said that waterways also contain large amounts of debris and that river banks are unstable. She recommended that people stay at least 20 feet away from the banks, and stressed that parents should always supervise children.

Clark also said that temperatures in waterways could be as low as the 40s. When water is that cold, she said, hypothermia sets in quickly and impairs movement. She said reservoirs could be somewhat warmer if they are heated by the sun, but stressed that conditions throughout the state are extremely dangerous. Clark advised visitors to forest areas to read signs and check their surroundings for hazards. She said that dangerous conditions could persist until mid-July if weather conditions remain constant.

"We can't force mother nature to dry out more quickly," she said.