BANNACK STATE PARK - A ghost town in southwest Montana received extensive damage Wednesday afternoon during a flash flood that resulted in the cancellation of this weekend's Bannack Days and closed the park for the near future.
Tom Lowe, assistant manager at Bannack State Park, said the flood washed out one building and destroyed half the boardwalk in the historic gold-mining town that dates back to 1862 and was Montana's first territorial capital.
The park is one of the top tourist attractions in southwest Montana, welcoming 32,900 visitors in 2012. About twenty tourists were visiting at the time of the storm, and though Lowe said four tourists were injured, none of the injuries were serious.About 50 of the 60 buildings that make up the town had some damage from the storm, which began at about 4:15 p.m. and lasted for about 30 minutes, according to Lowe.
The historic building that was destroyed was the Assay Office next to the Meade Hotel. The Assay Office is considered one of the first and most important buildings in the town. The office was where gold discovered in the area was first measured and assessed.
The storm caused a surge of water carrying mud, rock and debris through the center of Bannack. Lowe said the flooding came from Hangman's Gulch on the north side of the town.
Jim Brusda, a meteorologist with the National Weather Service in Great Falls, said a flash flood warning was not in effect for the area.
According to Brusda, two storm cells in the area caused a significant runoff that resulted in the flood. One storm, over Bannack, dumped three-quarters of an inch of rain in less than an hour, while another storm, over the Pioneer Mountains north of Bannack, also affected the water flowing down the hills and gulches surrounding the town.
Along with the cancellation of this weekend's annual Bannack Days, the park, including its two campgrounds, are expected to be closed for at least the next two weeks.
Lowe stressed that visitors should avoid the area because the road leading to the park is closed. He said the road did not receive much damage from the flood, but it is blocked off.
David Marx, disaster and emergency services coordinator for Beaverhead County, said he toured the park on Wednesday after the flood and was surprised at the extent of the damage.
"The street (through town) looks like the bottom of a river bed," Marx said.
Marx said it was rare that a flash flood to be so localized and extensive.
"They've had some flash flooding in the past, but nothing like this," Marx said.
Lowe said the park is still investigating the extent of the damage and it won't know the full dollar cost for at least a couple of days. State officials were in Bannack on Wednesday to help with that estimate.
Closed road in Yellowstone
The same storm system that hit the Pioneer Mountains north of Bannack caused a mudslide that shut down one of the main roads into Yellowstone National Park, dumped 1¼ inch hailstones east of Helena and caused minor flooding and mud runoff north of Helena where a fire burned last year.
U.S. Highway 89, 8 miles north of Gardiner, was buried in mud and rock, up to 10 feet in some places. The highway from Livingston leads to Yellowstone's northern entrance and is typically busy with park visitors this time of year.
Highway workers scrambled to remove the debris, and the highway was reopened to traffic at 11:30 p.m. Wednesday, Department of Transportation spokeswoman Lori Ryan said.
The cleanup is expected to last another two days, with traffic delays expected, before workers can examine the roadbed for damage, she said.
The brief, intense storm likely did not do much to help drought conditions in southwestern Montana, which is the driest part of the state. It happened too fast to affect the soil conditions and it packed lightning that may have left new fires smoldering, Brusda said.
Conditions in the area are expected to be hot with low humidity over the next few days, ideal conditions for wildfires, he said.
But the wind is expected to be light, which may help firefighters extinguish new starts before they spread, he said.