Major rainfall combined with seasonal snowmelt has forced Yellowstone National Park to close in the middle of its summer rush, causing an estimated 10,000 visitors to evacuate the area as roads and buildings collapsed into the surging Yellowstone River.
The entire park, which is larger than Delaware and Rhode Island combined, has been closed, though superintendent Cam Sholly said in a news conference that Yellowstone’s southern loop, which has access to popular sites including the Old Faithful geyser and the Grand Canyon of the Yellowstone, could open within a week. “We will not know timing of the park’s reopening until flood waters subside and we’re able to assess the damage throughout the park,” Sholly said. The northern half of the park, where concrete entrance roads fell into the river, could remain shuttered until early November.
The floods and mudslides began when a storm last weekend dumped as many as three inches of rain and warming temperatures melted 5.5 inches of snow that largely fell over Memorial Day weekend. The combined water caused the flooded Yellowstone River to rise six feet within a 24-hour period and move at an incredible speed. In Gardiner, Montana, the Yellowstone River was recorded flowing at 51,000 cubic feet per second; the highest previous recording was 31,000 cfs. With forecasts predicting more rain and warm weather for the coming week, it’s possible that more flooding could occur as the remaining snowmelt rushes into the river.
Superintendent Sholly said that 12 people in the backcountry of the oldest national park were finding their way out without an airlift and that there were no flood-related injuries to any staff or visitors. But two towns in Montana that function as gateways to the park, Gardiner and Cooke City, were cut off from supplies and clean water; municipal services were also shut down. Local businesses offering rentals and vacation services are expecting to take a major hit with a large section of Yellowstone closed during its 150th year. On Tuesday, Montana’s lieutenant governor declared a statewide disaster to free up resources. Governor Greg Gianforte could not do it because he was enjoying a vacation in Tuscany.
“I’ve heard this is a thousand-year event,” Sholly said of the flooding. But more frequent rainfall is expected as climate change warms the region: According to a study last year by the U.S. Geological Survey, annual precipitation is expected to increase in the area by as much as 15 percent by 2100.