Lillian Poulsen

(MTFP) Ronald Regan, 65, has lived in the Orchard Homes neighborhood of Missoula for most of his life.

His two properties, one of which his parents bought in 1961, are located in an area that county floodplain administrators recently determined would be most affected by severe flooding, should it occur. If that determination stands, Regan and others say the impact on their property will be dire.

“This decision makes it impossible for me to make any developments and reduces the value of my home,” Regan said. “This affects me a lot.”

Matt Heimel, Missoula County’s floodplain administrator, said the update to the floodplain better reflects the risks that homeowners like Regan face, the Montana Free Press reports.

“Orchard Homes is a very high-risk area, and the reason is because that was part of the original river channel,” Heimel said. “When the river floods, it’s trying to fill in its historical channels.”

The floodplain mapping project began in 2020 to update current maps that use flood data from the late 1970s. The project mapped the chance of a 100-year flood occurring, an extreme natural disaster that has a 1% chance of occurring in any given year, in the Clark Fork, Bitterroot River and Rock Creek, Heimel said.

At the end of November, Missoula will send postcards to residents affected by the floodplain mapping update. The final map won’t be approved by the federal government until 2026 or 2027, but Missoula County may adopt it as early as 2025.

Adopting the proposed map would add about 660 properties to the 100-year floodplain, Heimel said. The plan also removes about 390 structures with almost 700 properties experiencing no change, he said.

Areas near the Clark Fork, Bitterroot River and Rock Creek may be affected with properties in Bonner, West Riverside, Clinton, East Missoula, Frenchtown, Lolo and Orchard Homes experiencing the most changes, according to a Missoula County press release.

“We’re doing this to get ahead of public health and safety impacts,” Heimel said. “Because of climate change, these extreme flooding events are becoming more common, and the severity is increasing.”

The updated maps use technology that measures the precise elevation of the ground and updated calculations of the amount of water that could be expected during different levels of flooding, he said.

Some people living in areas that will become part of the regulated floodplain are concerned about the value of their homes, whether they have access to flood insurance and what the government will require them to do.

Heimel said people aren’t required to make updates if their homes were built before the proposed mapping update. But, if people living on part of the regulated floodplain want to update their property, they must first receive approval from the county’s floodplain administrators, he said.

People who have federally backed mortgages and live on the floodplain are required to have flood insurance through the National Flood Insurance Program, Heimel said.

One problem the county and city see is that many homes in the floodplain areas have foundation walls with a crawl space, Heimel said. This can cause problems because the walls aren’t made to withstand flood water, he said.

Homeowners with this type of foundation can retrofit their homes to make them safer by adding concrete slabs and filling in the crawl space, Heimel said.

“Unfortunately, it’s a lot of money,” Heimel said. “One thing people should consider, though, is that the price of retrofitting and getting flood insurance is significantly less than the price of losing their homes and everything they own.”

While some residents, like Regan, disagree with this proposed plan, others believe the update is beneficial for Missoula.

Riki Mancinetti, 74, has lived on Juneau Drive in Missoula since 2015. Like Regan, she remembers the 2018 flood that flooded her street and created ponds in her backyard. She said her crawlspace filled with about a foot of water.

Mancinetti said she isn’t surprised by this proposed change.

“I mean the river is right on the other side of the levee,” Mancinetti said, pointing to the levee she can see from her backyard. “As long as we’re given a heads up to get out, then we’ll be fine.”

Mancinetti believes this change will protect people and their homes. While the 2018 flood didn’t significantly damage her home, she said she’s worried about what a more severe flood could do.

“There’s a lot of water around us that people don’t really think about,” she said. “This area could easily flood, and we’ve seen it happen.”

The best option for mitigating flooding is to leave the natural floodplain alone, Cassie Tripard, Missoula’s floodplain administrator, said. In areas where the river is forced up against a levee, flooding will occur, she said.

That’s why building stronger levees might not fix the problem, Tripard said. Instead, once the federal government adopts the maps, Missoula will focus its efforts on mitigating flooding upstream.

The last 100-year flood happened in 1908 in the Clark Fork River, Tripard said.

“There’s no one alive in Missoula today who has seen this happen, so it’s hard to understand the stress of something that you haven’t seen,” Tripard said.

People, like Regan, may remember less severe floods, so they might think their property can withstand damages, Tripard said.

Regan’s home has stood for most of his life. Losing it, though, would be terrible, he said, as it’s the home he grew up in and the last place his parents lived before they died.

He uses sandbags to keep his crawlspace from flooding and believes the city and county should focus on upstream flooding to protect his neighborhood.

“Water doesn’t really get up to my home from the river, so I don’t think there’s an issue,” Regan said.

This article first appeared at Montana Free Press