Am I at risk? How to find out if you’re in a floodplain

The state’s Be Ready Utah website links to a Federal Emergency Management map that highlights areas at risk for flooding.

Residents can put in their city, zip code or address to assess the area around them.

However, Summit County Emergency Manager Kathryn McMullin says those maps aren’t the only predictor of risk.

“You should know if you live within a floodplain,” McMullin said. “But I don't want people to get too wrapped up in over-analyzing that map and then being surprised if they still experience some type of inundation.”

Wasatch County Director of Emergency Management Jeremy Hales says the federal government’s map is just a snapshot in time. In fact, the data for his area date back to 2012.

“There's been some changes, obviously, to the way things are going. There's more community development,” Hales said. “So the thing is, anywhere it rains, it can possibly flood.”

FEMA shows most of Heber City is in a floodplain with 0.2% annual risk of flooding.

“Most of it is just due to the way the flood channel can route through Heber,” he said.

There are other floodplains in cities and towns across the Wasatch Back, including along Swede Alley and Daly Avenue in Park City.

Any and all areas adjacent to streams, rivers and reservoirs, predictably, stand some of the highest flooding risk.

One of the biggest concerns is the Weber River, which runs through Kamas, Marion, Oakley and near Coalville. Areas along there saw flooding back in 2011. Because of the recent drought, reservoirs fed by the Weber River are low, so they may take more water and offset the risk of overflow.

McMullin says there’s a complicated confluence of factors that determine whether at-risk areas do flood. And they change all the time.

“What's the soil moisture? What's the soil temperature? All of those,” she said. “It's really dynamic.”

There are the more obvious ones too, such as how much snow there is, how much water it contains and how densely packed it is.

Even though these change day to day, there are certain areas to flag.

Data collectors in the Smith and Morehouse area and the Parleys Summit area have recorded soil moisture at or above 60%.

McMullin says it will be a challenge for that soil to take on more water.

“That’s a little high for us to be able to absorb more,” she said. “So then what you do is you make sure that drainage areas are clear, culverts are clear, points of collection are monitored. And that's what our public works operators are doing all the time.”

McMullin says homes built in floodplains usually need to abide by codes that make them more resilient. Outside of flood-prone areas, there might not be the same building codes.

“They may have been a little complacent in their landscaping, making sure that it was filled to drain away from their home, because they thought they were safe not being in a floodplain,” McMullin said. “And then when the water comes from snowmelt or groundwater, or something like that, then they still have damage.”

Whether flood insurance is worth it will really just depend on personal financial factors. People who do want to add flood insurance should know most policies take 30 days before protection kicks in.

Mitchell Elliott

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KPCW

Summit and Wasatch Counties have made sandbags available at public works and other municipal buildings for free, for everyone.

• Click here to view FEMA’s floodplain map. Note: blue signifies more risk than orange. Refer to the legend for different degrees of risk.
• Click here to find sandbagging stations in Summit County.
• Wasatch County has a sandbagging station in Heber City at its public works building at 1891 W. 3000 S.
• Click here for the Utah Snow Survey. Click “Interactive Map!” to view data on snow water equivalent, snowfall, soil moisture, reservoir levels and other flood factors.