United states

Yellowstone Floods are 1 in 500 years, says US Geological Survey

Unprecedented rain and rapid snowmelt in recent days have caused rivers in parts of Montana, Wyoming and Idaho to burst their banks, engulfing bridges and sweeping entire sections of the roadway.

More than 10,000 visitors to Yellowstone National Park have been forced to evacuate. All entrances to the park are expected to remain closed until at least Monday.

“In two jets, the Yellowstone River at Corvin Springs and the Yellowstone River in Livingston, the peak flow was 0.2% (or 1 in 500 years) higher than the flood,” USGS hydrologist Catherine Chase said in a statement. .

Downstream, the Yellowstone River in Billings was between 1% (or 1 in 100 years) and 0.2% (1 in 500 years) of flooding, according to the report, which notes that flow data “are currently reported as “temporary” until further analysis of the flow and data channel is completed. ”

However, Chase notes in the report that “while these floods are often referred to as greater than (or less than) 1 per 500-year event, they are equally likely to occur in any given year.”

USGS frequencies are calculated from historical data on Yellowstone River locations. As CNN reported this week, scientists have shown that climate change is affecting the frequency with which extreme weather events occur, and this trend is expected to continue as the planet continues to warm.

In a three-day period last week, Yellowstone National Park received about two to three times more than typical rainfall for the entire month of June, and rainfall this month is already over 400% of the average in northwestern Wyoming and southern Montana, according to the National Weather Service. service.

Yellowstone remains closed

All five entrances to Yellowstone Park remained closed on Friday as flood recovery and repair efforts are underway in preparation for the park’s reopening, according to a statement from the park’s manager’s office.

According to the announcement, the National Park Service still has no estimated date for the reopening of the entire park – no idea of ​​the total cost of repairs. The publication outlines an extensive list of repairs needed for roads and infrastructure in each part of the park so that it can be reopened.

“We have made tremendous progress in a very short period of time, but we have a long way to go,” superintendent Kam Sholi said in a statement. “All objectives for emergency situations and safety of life in the park have been achieved or stabilized within the first 96 hours of the flood, without serious injury or death.”

The park service said it was “very possible” they would be able to reopen the southern chain of Yellowstone sometime next week, although probably with “certain modifications to the entrance for visitors.”

“We have an aggressive plan to rebuild the north and resume operations in the south,” Sholi continued. “We appreciate the tremendous support from the National Park Service and the leadership of the Home Office, in addition to our surrounding congressional delegations, governors, counties, communities and other partners.

Montana Gov. Greg Gianforte has expressed optimism about flood recovery and recovery, encouraging continued tourism in Big Sky. “The best days are ahead of us,” he told reporters on Friday.

“We are open. You have to come, “Gianforte told Yellowstone Park. “The vitality of our communities depends on that. We are open to business and we want you to come.”

Authorities have previously said the northern part of the park is likely to remain closed for the rest of the season.