Eventually Chelsey and the youngster were hauled back into the boat, at which point family members began performing CPR on her.
The family reached the shore a short time later where attempts to resuscitate Chelsey continued, but she was pronounced dead a short time later.
The San Juan County Sheriff's Office gave a little further explanation as to why it took so long for the family to turn their boat around and pick Chelsey and the boy up.
"A significant distance developed between the mother and child and the houseboat before the houseboat could be shut down', a report posted to social media stated.
Deputies said a Chelsey's brother then untied a smaller boat being towed by the houseboat in an attempt to reach the pair of them faster but by that time Chelsey was completely under the water.
She was able to hold her son above water long enough for him to be rescued.
The two-year-boy son was flown by medical helicopter to a hospital in Flagstaff, Arizona, but has now been released.
The doting mother worked as a lawyer in Denver. The firm posted a statement in memory of Russell on its website Thursday: "Chelsey was an amazing mother, an exceptional legal talent, an extraordinary athlete, a loyal and generous friend, and left us all better for knowing her. She is sorely missed."
The law firm's page about Chelsey states: "Ms. Russell was born and raised in Denver. After graduating with a BSBA in General Business from the University of Denver, she worked her way from land associate to landman for a local oil and gas exploration and development company.
"Ms. Russell received her JD from the University of Denver in 2011, where she was a contributor to the Race to the Bottom Blog, a nationally recognized student/faculty collaborative corporate governance blog. Ms. Russell is actively involved in her community and enjoys running marathons, hiking, skiing, and spending time with her family."
"There are no words to convey the tragedy of losing a loved one like this," said Teri Tucker, Acting Superintendent of the national recreation area. "Our hearts are with the family and friends of the victims during this time of unexpected pain and loss."
The cause of death is presumed to be drowning, pending coroner's confirmation.
There have been more than 120 fatalities at Lake Powell in the last few decades, mainly caused by the fact victims were not wearing life jackets.
While life jackets are required for children 12 years of age and under, all boaters on Lake Powell are encouraged to wear them.