The Merced River's unusual force for this time of year made wading near a waterfall particularly deadly for three Yosemite visitors.
Three hikers are presumed dead after being swept over Vernal Fall, a 317-foot waterfall at Yosemite National Park, on Tuesday, according to a National Park Service news release.
Witnesses said the visitors climbed over a guardrail to put their feet in the water about 25 feet from the waterfall's edge. The hikers have been identified as Ramina Badal, 21, and Hormiz David, 22, both of Modesto, California; and Ninos Yacoub, 27, of Turlock, California.
Park officials announced Wednesday that they were presuming the visitors to be dead and will intensify search efforts as soon as theÂ river reaches a level low enough to look for bodies.
The Mist Trail, where the visitors were hiking, sees about 1,500 guests each day, according to the Park Service. In May, another hiker slipped from the popular trail into the Merced and drowned. Counting Tuesday's accident, there have been six water-related deaths at Yosemite this year.
Western rivers have been at record levels this summer due to large snow packs and a cool spring.
At this point in the year, the Merced would typically be at about a â€śtrickleâ€ť at Vernal Fall, said Dave Steindorf, California stewardship director for American Whitewater. Instead, the water is still gushing at levels that are rarely seen past June. Steindorf said this is great news for experienced paddlers but can create especially dangerous situations for hikers, bathers and waders who are less familiar with river hazards.
â€śWalking out into a river, if youâ€™re up to your knees, thatâ€™s about as far as you can go with being able to maintain your footing, even with just moderate force,â€ť Steindorf said.
Steindorf pointed to U.S. Geological Survey data that say the historic median level for the Merced just below Vernal Fall is 298 cubic feet per second. Right now, itâ€™s at 1300 CFS. That the Vernal Fall races over a solid piece of slick granite compounds the areaâ€™s danger, he said.
â€śWhen you get this late in the season and people are used to those rivers being a trickle, they donâ€™t understand how powerful they can be,â€ť Steindorf said. â€śPeople wouldnâ€™t consider walking out into a blizzard without any clothes on, but unfortunately, people will go into a river thatâ€™s higher than normal and not have life jackets or really the ability or the skill to avoid (accidents).â€ť
No matter how forceful or gentle the flow of the Merced, Steindorf said, he would never recommend entering a river above Vernal Fall.
â€śGetting in any river above a significant hazard. You have to exercise even more caution, and the right answer is that you shouldnâ€™t get in the water,â€ť he said. â€śOne of the big messages here is (to) provide some education on what is safe.â€ť
Yosemite places guardrails and multilingual signs in places that are hazardous, but deciding to heed those warnings is a decision left up to individual visitors, Kari Cobb, a Yosemite Park ranger, said Wednesday.
"Visitors that want to go around guardrails ... it's up to them," Cobb said. "It's something that does happen, and it's completely up to the visitor to know what safety concerns are around and take responsibility for their own actions.â€ť