The New Mexico State Police Search and Recovery Dive Team called off its search for Dylan Redwine in Vallecito Reservoir on Monday night, said Lt. Jennie Pierce, the commander of the dive team.
Dylan has been missing for more than one week.
The New Mexico State Police dive team started searching the bottom of Vallecito Reservoir in southwest Colorado for Dylan on Sunday when cadaver-sniffing police dogs homed in on a section of the reservoir, Pierce said.
The dive team spent two days searching the area and is confident the dogs were wrong, Pierce said.
"We had a specific area we were asked to search," she said. "At this time, we feel that he's not there."
Dylan was last seen by his father, Mark Redwine, on Nov. 19, said Dan Bender, a La Plata County Sheriff's Office spokesman.
Mark Redwine lives in Vallecito near the reservoir. Dylan was spending Thanksgiving with his father because of a court-ordered visit.
The La Plata County Sheriff's Office, La Plata County Search and Rescue and hundreds of volunteers have scoured the Vallecito and Bayfield areas in recent days looking for Dylan.
On Sunday, the sheriff's office asked for New Mexico State Police to search the bottom of the reservoir, Bender said.
New Mexico police have more divers and more sophisticated equipment than law enforcement agencies in southwest Colorado, he said.
New Mexico's dive team is comprised of state police officers from all across the state. It goes on about 30 to 40 recovery missions per year, including several at Navajo Lake, Pierce said.
The team searched the south end of the reservoir on Sunday and didn't find any clues about Dylan's whereabouts, Bender said.
On Monday, six members of the scuba-diving team boarded New Mexico State Police boats equipped with sonar and crisscrossed the lake, Bender said.
The New Mexico police's dive team has members from Albuquerque, Roswell, Hobbs, Deming, Raton and one of the divers — Joe Schake — is a Farmington native, Bender said.
The divers could only stay under for about 20 to 30 minutes at a time because the water temperature was between 38 and 42 degrees, he said.
The divers wore dry suits to keep their core temperature stable but they quickly lost dexterity in their fingers because of the water temperature, Pierce said.
The lake is at 7,700 feet above sea level which can complicate how the diver reacts to the oxygen, helium and nitrogen combination in their air tanks, Pierce said.
The divers went as deep as 40 feet below the surface, where visibility was about seven or eight feet, Bender said.
Diving into Vallecito Reservoir in those conditions "is an instant headache," said Jesse Kuzma, a master scuba instructor and the owner of Trinity Diving, a scuba-diving school in Aztec. "They are going through some tough times."
Kuzma, who trains with the state police divers, said they are experienced at diving in high-altitude, cold-water lakes.
"We know what they're going through," Kuzma said. "And (scuba divers) avoid those conditions as much as possible."
Other search and rescue members and volunteers searched the lake's 12-mile shoreline and surrounding areas Monday in hope of finding Dylan alive.
Mark Redwine told investigators he last saw Dylan at 7:30 a.m. when he left his son at home and ran errands.
Dylan was gone when his father returned home at 11:30 a.m., Bender said.
Dylan's parents are divorced and Dylan moved from Bayfield, Colo. to Colorado Springs in the summer with his mother, Elaine Redwine, and a brother.
Dylan was reportedly unhappy about the Thanksgiving visit to see his father, Bender said.
Bender said Dylan's family members are cooperating with investigators.
Elaine Redwine, Dylan's mother, told reporters that she believes Dylan did not run away from home on his own and that he was taken against his will. She said he is not the type of child who would spend time alone in the wilderness or go days without calling his parents.
Investigators with the sheriff's office and the FBI are considering everything from an abduction to a runaway, Bender said.
"We know that some people are upset that we are even considering the possibility that Dylan may have run away. But, we are working for Dylan and we owe it to him and to his family to consider every possible scenario that could have caused him to drop out of sight for a week," Bender said. "To disregard any potential circumstance could cause us to overlook a possible clue that will lead us to Dylan."