An unusually cool spring and ensuing stubborn snowpack have local officials preparing for the worst. Comparisons have been drawn between the current conditions and those leading up to the catastrophic 1964 flood – an event that, if it were to occur today, would decimate areas where development has boomed in past decades.
At last Friday’s flood coordination meeting with county and city emergency officials, the National Weather Service briefed the group, saying because of cool spring weather and continuing snowfall that the mountain snowpack above the Flathead Basin is at 119 percent of the 30-year average for this time of year. After more cool weather earlier this week, a warming trend starting Thursday and continuing through the weekend could bring rapid melting and a quick rise in river levels.
“High snowpack is good news as far as drought and irrigation is concerned, but the bad news is that it also creates higher flood potential,” Ray Nickless, NWS hydrologist, said.
The flow forecast for the Middle Fork Flathead River projects high water to reach somewhere between 9.1 and 11.7 feet, with flood stage being 10 feet. The North Fork Flathead River, where the flood stage is 13 feet, is projected to peak between 11.7 to 16.8 feet. The main Flathead River is projected to be between 11.7 and 16.8 feet; flood stage is 14 feet.
Specific flow projections aren’t available for the Whitefish and Stillwater rivers, but Nickless was projecting last week that they would meet or exceed flood stage.
“If we get into a period where there’s a week of 80-some degree temperatures we can see levels get up there fast, and probably see some type of flooding,” he said. “A large rainstorm can turn average flooding to a major flood, and we’re entering our rainy months.”
Mark Peck, former director of Flathead County’s Office of Emergency Services, said there is cause for concern. Peck stepped down last week and is being replaced from within the office by Cindy Mullany.
“On a scale of one to 10, it’s probably a six right now,” Peck said. “It always seems to be just one weather event away.”
Mention flooding in the Flathead Valley and the conversation inevitably turns to the floods in early June of 1964. Extended heavy rains and near-record mountain snowpack turned creeks to raging rivers as roads and rail lines washed out, several hundred homes were swept away and more than 20,000 acres were covered in as much as four feet of water. The Flathead River crested in Columbia Falls at 26.5 feet, more than 12 feet above flood stage.
Since then, the valley has seen unprecedented growth, adding countless homes and businesses in areas that were hardest hit during the 1964 flooding. Local officials are particularly concerned about Evergreen.
“If we had a repeat of the ‘64 flood, Wal-Mart, Shopko, Woodland Park – all those places in Evergreen that didn’t exist before – would be inundated by several feet of water,” Peck said.
There are at least 6,000 homes or businesses located within the flood hazard area, or 100-year flood plain, and countless more in the 500-year flood plain, according to Jeff Harris, director of the county planning office.
“Now, when we review a land division we don’t allow or permit 100 percent of a lot to be in the floodplain – part can be in as long as they have enough land to build off it,” he said.
But that hasn’t always been the case. There wasn’t even a county flood insurance program until the mid-1980s and the floodplain management program was implemented slowly. “I wouldn’t suggest they did anything wrong; it’s part of the evolution of a community,” Harris said. “But, I do think from this point into the future we need to all understand that flooding happens and certain land uses aren’t appropriate within the 100-year floodplain.”
A recent study by the Flathead Lake Biological Station shows similarities in the climate and geological patterns that affect flooding between 1964 and today. The report, which followed landscape change on the Nyack floodplain over 60 years, found a strong correlation between regional climate patterns, changes in floodplain habitats and flood magnitude, Diane Whited, a research associate at the station, said.
Despite similarities to the 1964 season several city and county emergency personnel said they didn’t think there’d be major flooding this year, and noted that a major rain event – the catastrophic impetus for the 1964 flood – isn’t in weather forecasts, yet.
Still, officials are advising county residents living in flood-prone areas to begin the necessary preparations in case of a quick evacuation and plan for their homes and pets or livestock. Officials are working to make arrangements for special population groups, such as the homebound or those in nursing homes.
“People don’t need to be staying up at night worrying, but they should be thinking about the process and what they would do in case of flooding near their home,” Peck said.