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Why Thousands More Treasure Valley Residents May Have To Buy Flood Insurance

Adam Cotterell
Boise State Public Radio
According to FEMA's current floodplain maps, this bank of the Boise River would contain floodwaters. In the first draft of the new maps it wouldn't. Nearby Park Center Blvd has the most land added to the floodplain in the city of Boise.

Thousands more people in the Treasure Valley may be required to buy flood insurance in the near future.  The Federal Emergency Management Agency (FEMA) is revising its floodplain maps for the Boise River, and a lot of neighborhoods near the river could be added, requiring more home and business owners to buy potentially costly flood insurance.

Barbara Horne's neighborhood in Eagle is one of those. Horne walks her dog around the pond behind her house.  The pair could reach the Boise River in five minutes. Despite living so close to the river, Horne does not have flood insurance.

“[I] hadn’t thought about it flooding,” Horne says. “I really hadn’t. I’d be very surprised if [it did flood].” 

Horne retired to Eagle from California and didn’t know flooding was an issue. When she bought her house, she wasn't required to get flood insurance because her relatively new subdivision was built with flood mitigation in mind. That pond behind her house isn't for looks; it's for flood water.

On current FEMA maps her neighborhood is not considered to be in the floodplain. But in the first draft of the new ones Hornes’ house would be.

So would about 75 more properties in Eagle, 700 in Boise and 2,500 in Garden City. Nampa, Caldwell and other towns on the Boise River will also be impacted along with residents on unincorporated county land.

Credit Data from FEMA, screen grab gardencity.org
This draft map shows eastern Garden City. It's the area most impacted by FEMA's proposed floodplain changes. FEMA thinks Garden City levies are not high enough to stop a 100 year flood.

Properties in the 100-year floodplain are considered to have a 1 percent chance of being flooded each year and a 26 percent chance over 30 years. Properties with federally-backed mortgages in communities that take part in the National Flood Insurance Program are required to have flood insurance.

Ryan McDaniel is the Risk MAP program manager with Idaho’s Bureau of Homeland Security, the state emergency management agency that coordinates with FEMA. He says this is not an example of the federal government forcing people to buy insurance, because communities choose to participate.

“If I was a local citizen I would take these maps seriously,” McDaniel says. “The maps show that the flood risk is actually higher than was previously thought.”

McDaniel says flood maps need to be updated periodically because floodplains are dynamic. Natural forces change them, but so does human action. For example, if a new subdivision is build next to an existing one that's not in the floodplain, the original housing development could be added to the map because the new homes change where flood waters go. McDaniel compares it to putting bricks in a bathtub.

“As you fill in the tub with development, you put in houses, businesses…it makes the water level rise,” McDaniel says.

Eagle homeowner Barbara Horne says she doesn’t have a problem with buying flood insurance if it’s required. She says she’ll do what it takes to protect her home, within reason.

David Martin with Idaho Farm Bureau is a FEMA recommended insurance agent in Eagle.  Martin gave KBSX an estimate for Horne’s house.

He estimates if Horne were to buy flood insurance now – before the new FEMA maps are finished – it would cost $435 per year.

“With a reassessed flood zone, that property owner could be looking at probably $600 to $1,200 a year,” he says.

Martin says typically when a home is added to a floodplain map the insurance rate will go up by two or three times. But he says FEMA makes the rates start out artificially low.

But, Martin says, things like having a basement can make rates jump significantly. Some homeowners could pay several thousand dollars more.

There’s a sort of national consensus now – even in congress – that more people near water need to buy flood insurance and more of them need to pay closer to market value. That’s after FEMA’s budget has gone into the red after several flood disasters in recent years. FEMA is still dealing with flood insurance problems from Superstorm Sandy which happened more than two years ago, and the agency is just beginning the process now after devastating floods hit Texas.

But when FEMA changes flood insurance maps there’s almost always pushback from developers, real estate agents, property owners and cities. That’s happening behind the scenes in the Treasure Valley now.

In January FEMA  representatives came to the Treasure Valley to present the first draft of the maps to the cities. In February Boise, Garden City and Eagle wrote a letter asking FEMA to reconsider the maps.

“We’re not saying the maps are wrong,” Boise’s city planning director Hal Simmons says. “We just have questions about the data they used, and stated that concern and have asked them to give us time to go back and kind of analyze the results ourselves.”

FEMA didn’t intend for this part of the process to be public. But later this year the agency says it will release the next draft of the maps and ask for public comments. If history is any measure, that’s when the outcry will start.

Rob Flaner has seen this play out many times from both sides of the issue, first working for FEMA for two decades. Now he works for a Seattle-based engineering firm that contracts with cities and counties in the west on flood hazard mitigation. He says FEMA maps aren’t perfect, but they’re very good.

“I’ve spent a lot of time responding to flood disasters," Flaner says, "and it’s amazing when you look at where the water actually goes in a flood, and how [it’s] projected where [it’s] going to go on a map, they’re very similar."

Ryan McDaniel says the new maps are based on the best science available. For example, this is the first time the federal agency has used a technique called LIDAR to map the Boise River floodplain. It uses airplanes to bounce lasers off the ground to make 3D computer models.

But in another sense, Flaner says the maps are always completely wrong. He says they represent the floodplain at a point in time. The current flood insurance maps for Ada County were adopted in 2006, but the scientific work used to create them was done nearly a decade before that. While maps are being drawn and then debated, people are changing the land they represent.

Flaner says it’s easy to see why cities sometimes object to changes in insurance maps.

“[If] you’re Garden City where you got a new flood map that shows two thirds of your city now in the floodplain, yeah, you’re going to appeal that map,” Flaner says.

Boise’s Hal Simmons says he’s glad FEMA updates the maps periodically because the city’s top priority is public safety. But he says there are other things to take into account.

“There’s a real economic impact on our land owners in compliance with the floodplain regulations in terms of insurance, in terms of building standards,” Simmons says. “And again, we just want to ensure that the boundaries are defined properly and that if it costs more money, that there’s a reason for that.”

We’re several years into the process for the new maps, and it's not clear when the final ones will be adopted. That timeline depends at least in part on how much residents along the Boise River and their cities challenge the federal agency's floodplain assessment.

Find Adam Cotterell on Twitter @cotterelladam

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