According to NPS,

On Saturday, September 19, 2020, at approximately 6:30 p.m., Robert Sanders, a 50-year-old male from Centennial, Colorado took a hike from the houseboat he was staying on in Mountain Sheep Canyon on Lake Powell and did not return. He was part of a group of 7 who stated Mr. Sanders wanted to get a better vantage point to look at another houseboat in the area that had flags displayed. At 7:42 p.m. they reported him as missing to the National Park Service (NPS) Glen Canyon Communications Center via marine band radio.

On Sunday, September 20, 2020, NPS Rangers responded to Mountain Sheep Canyon where an extensive search took place with ground crews, a helicopter from Classic Lifeguard, and the NPS fixed wing aircraft. The search continued on land September 21 and 22. On September 22 the NPS Dive Team was also activated to conduct a water search of the area.  

At approximately 3 p.m. on September 22 Mr. Sander’s body was located. He was found on land approximately 2 hours by foot away from the houseboat, and 15 minutes from the shore. Searchers found tracks and it appears he hiked along the shore of Lake Powell before turning inland. The cause of death is under investigation. 

National Park Service Rangers transported the individual to the Halls Crossing Marina where he was transferred to a San Juan County Sheriff’s Office Medical Investigator. He will be transported to the Utah State Medical Examiner’s Office in Salt Lake City, Utah. The incident is under investigation by the National Park Service and San Juan County Sheriff’s Office while awaiting the findings of the Medical Examiner.

The National Park Service and San Juan County Sheriff’s Office express our condolences to the family. No further details are available at this time.

Mountain Sheep Canyon is located two canyons upstream of Dangling Rope Marina. It consists of a waterway side canyon from the Main Channel of Lake Powell inside San Juan County, Utah. Terrain in this area is made up of sandstone slopes and cliffs and water depths ranging from a few feet to 80 feet.

Lake Powell is a man-made reservoir on the Colorado River, straddling the border between Utah and Arizona. It was created by the flooding of Glen Canyon from the controversial Glen Canyon Dam, which also led to the creation of Glen Canyon National Recreation Area, a popular summer recreation destination.