CHATFIELD STATE PARK, Colo. (CBS4) – The Summit County Sheriff’s joined the search for a missing 18-year-old man at Chatfield State Park. They brought a water-based cadaver dog to search Chatfield Reservoir after South Metro Fire and Colorado Parks and Wildlife ended their search on Monday.

(credit: Colorado Parks and Wildlife)

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Crews hope the dog will identify target points for divers on Tuesday.

The teenager, who friends and family have identified as Aric Whitacre, never resurfaced on Friday when he and another swimmer had trouble near the Catfish Flats area. Bystanders helped rescue the second swimmer.

Aric Whitacre (credit: Whitacre family)

Crews ran into obstacles over the weekend as remote equipment encountered plants and silt underwater. They’ve used numerous tools including drones to look for the victim.

“We’re using a bunch of different equipment – underwater drones, sonar, video equipment, but the aquatic vegetation that’s there is 5-6 feet tall and that doesn’t always allow your sonar to necessarily be effective,” said Jason Clay, Northeast Region Public Information Officer for Colorado Parks and Wildlife.

The lake area, shoreline and parking lot were closed on Sunday, but CPW asks the public to avoid the area to make for safe and more efficient conditions.

Still, some friends and family have voiced their concern over the large amount of people that continue to visit and recreate at the park while search crews work.

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“I thought it was really disrespectful and sad to see,” said Madyson Rosenhahn, a former high school classmate. “It made me want to cry.”

(credit: South Metro Fire)

As of Monday night, Rosenhahn was one of nearly 9,000 people who have signed an online petition urging CPW to close the reservoir until Whitacre’s body is found.

“He brought a lot of joy to my life and I feel like it’s necessary to sign the petition because he was such a good kid and I really want his family to be able to have some sort of closure and find him,” Rosenhahn said.

According to Jason Clay with CPW, search crews have been in communication with the family.

Throughout the search, parts of the shoreline have been closed off and crew members in patrol boats and on jet skis have been able to establish and monitor a perimeter around the search area without issue.

(credit: South Metro Fire)

“We’re completely understanding out of respect to the family and trying to get them the closure that we want, but at the same time as a state entity we have the obligation to provide recreation opportunities,” Clay said. “Our teams are able to be effective in their search and in their job, and since it’s a very large reservoir there’s still space for people to do that.”

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Search crews are expected to continue their efforts on Tuesday morning.

Conor McCue