Two people died while rafting a difficult stretch of the Selway River on Saturday, according to the Idaho County Sheriff’s Office.

The accident, in the remote Selway-Bitterroot Wilderness Area, happened between Double Drop and Wa-Poots rapids as the river surged from spring runoff. The names of the two people who died weren’t released pending notification of their families.

The Selway, a destination for expert rafters seeking big whitewater this time of year, hit a daily peak of about 18,300 cubic feet per second Saturday morning before dropping to about 17,300 by the afternoon.

According to the news release issued Monday, the Idaho County Dispatch received a call from the International Emergency Response Coordination Center that said it had received an SOS from a Garmin inReach device advising CPR was in progress at a location along the Selway River. About two hours later, a text came to 911 stating that a second person in the party also had fallen into the water and CPR was in progress on them. The second location was about 2 miles downstream from the original SOS.

The river flows for 47 roadless miles between the launch at Paradise to the take-out just upstream of Selway Falls. According to the news release, the accident site was “approximately 19 miles from the end of the road.”

Idaho Life Flight responded to the first location Saturday afternoon, and found the patient was dead. The service also confirmed the death of the second patient. Because of the location and equipment needed, Life Flight wasn’t able to transport the deceased patients, according to the sheriff’s office news release.

The U.S. Forest Service attempted to reach the location via mules, but was unable to get there because of steep terrain.

On Sunday, Two Bear Air responded. Because of flooding conditions and steep terrain, its crew used their helicopter winch system to get both victims out of the canyon to Cedar Flats, where they were turned over to the Idaho County Coroner, according to the news release.

Idaho County Sheriff Doug Ulmer expressed thanks to Life Flight, Two Bear Air, the U.S. Forest Service, Three Rivers Rafting and Coroner Cody Funke.

Marty Smith, the former owner of Three Rivers Rafting who has made more than 100 trips down the Selway, said on Saturday the river was just below a point where he would consider pulling out and waiting for flows to recede.

“We used to cancel at 20-21 thousand. I’ve canceled at 18,000,” he said. “When the flow gets high, it becomes less manageable. It just takes on different characteristics. The waves are irregular and there are no eddies.”

Starting near Double Drop, a Class IV Rapid, the river becomes especially treacherous at high flows.

“It’s four or five miles that are pretty continuous,” he said.

The upper Selway River is a coveted, multiple-day rafting trip that is regulated by permit for much of the whitewater calendar. During what is known as the control season that begins Thursday, the U.S. Forest Service only allows one group to launch each day. Flows typically peak in May or June when cold water gear like thick wetsuits or drysuits are required to guard against hypothermia.

By July, flows can recede quickly and the continuous whitewater that is possible at peak runoff earlier in the season becomes a series of pool-and-drop rapids.

The river hit daily peaks above 20,000 cfs on Sunday and Monday. The Northwest River Forecast Center calls for the Selway to hit 20,000 cfs again today and then starting to recede for the next several days.