The Arkansas River's flow could fall below optimum rafting levels for a few hours next week as searchers seek access to a hazard where they suspect a missing woman's body could be lodged.

“Hopefully it'll be a small, little bubble going down the river,” said Stew Pappenfort, senior ranger at Arkansas Headwaters Recreation Area, adding that the flow will likely return to normal after four to six hours.

Reducing flows to aid in a rescue is an unprecedented method in the area, and engineers at the Bureau of Reclamation are working on the specifics of its orchestration, he said.

First-year, off-duty raft guide Kimberly Appelson, 23, disappeared shortly after she was ejected from a boat near Frog Rock rapid on July 11.

The Breckenridge resident fell out near a notorious underwater sieve, which works likes a narrow tunnel of rocks funneling water and creating high pressures. At least six people have died at the site since 1990.

Search crews have had difficulty investigating the area since Appelson's disappearance because of high waters.

Search dogs brought to the site recently picked up a scent near Frog Rock.

“We're doing a little bit more work with dogs in the next couple days to see if they can identify a scent at the site to the missing person,” Pappenfort said.

The day she disappeared, Appelson was wearing both a life jacket and helmet.