Park officials warn Yellowstone flooding could be ‘thousand-year event’

Extreme flooding in Yellowstone National Park could constitute a “thousand-year event,” National Park Service officials said on a press call Tuesday evening. 

“This isn’t my words, but I’ve heard this is a thousand-year event,” Yellowstone Superintendent Cam Sholly said. “From what I understand, one of the highest cubic feet per second (CFS) ratings for the Yellowstone River recorded in the ‘90s was at 31,000 CFS, and Sunday night we were at 51,000 CFS.” 

Sholly noted that, despite the historic nature of the flooding, such events “seem to be happening more and more frequently.”  

Road conditions are particularly dangerous, Sholly said, as the park approaches its peak tourism season. Flooding on Highway 89 across the Montana border cut off access to the town of Gardner, he said, and while access has since been restored, several thousand park visitors were stranded in Gardner along with residents at one point. 

Sholly added that the road between Gardiner and Cooke City, Mont., will likely remain closed for the remainder of the season.  

Park County, Mont., Commissioner Bill Berg added the flooding had put some basic services at risk as well in parts of the county that can be accessed only through Yellowstone. 

“We can’t provide law enforcement services out there right now. Public health services, we can’t get out there to pick up the garbage. Some of this stuff is pretty basic,” he said. “We can’t get out there to help clean up the streets because they have their own flood event.” 

A combination of heavy rain and mountain snowpack led to extreme flooding Monday that forced the park to close first its northern entrances Monday, then all of the remaining entrances hours later.

As of Tuesday, park officials said the entrances would not reopen until Wednesday at the earliest. Much of the road leading to the northern entry appeared to have been washed away in video taken by NPS helicopters. 

Updated 3 p.m.