Denise Morgan, 36, of Austin, had left the campsite to find a restroom and didn't return. Her husband reported her missing Wednesday night.
Wade said the 15-foot cliff was about 25 feet away from the campsite at the park, located about 30 miles west of Austin. Morgan's body was found in about 12 feet of water.
"There are a lot of loose rocks" near the cliff, Wade said in a story for Thursday's online edition of the Austin American-Statesman. "It's not something solid that you can run up and down. Even in the daylight, it's kind of slippery."
Wade said there was very little light to guide her.
"When she went walking after dark, she apparently lost her footing and fell," he said.