by Theodoric Meyer ProPublica.
When Donna Edgar found out that new flood maps from the Federal Emergency Management Agency would place her house in a high-risk flood zone, she couldn’t believe it.
Her home, on the ranch she and her husband own in Texas hill country about 60 miles north of Austin, sits well back from the nearby Lampasas River.
“Her house is on a hill,” said Herb Darling, the director of environmental services for Burnet County, where Edgar lives. “There’s no way it’s going to flood.”
Yet the maps, released last year, placed the Edgars in what FEMA calls a “special flood hazard area.” Homeowners in such areas are often required, and always encouraged, to buy federal flood insurance, which the Edgars did.
FEMA eventually admitted the maps were wrong. But it took Edgar half a dozen engineers (many of whom volunteered their time), almost $1,000 of her own money and what she called an “ungodly number of hours” of research and phone calls over the course of a year to prove it.
Edgars is far from alone.
From Maine to Oregon, local floodplain managers say FEMA’s recent flood maps — which dictate the premiums that 5.5 million Americans pay for flood insurance — have often been built using outdated, inaccurate data. Homeowners, in turn, have to bear the cost of fixing FEMA’s mistakes.
“It’s been a mess,” Darling said. “It’s been a headache for a lot of people.”
Joseph Young, Maine’s floodplain mapping coordinator, said his office gets calls “almost on a daily basis” from homeowners who say they’ve been mapped in high-risk flood areas in error. More often than not, he said, their complaints have merit. “There’s a lot of people who have a new map that’s unreliable,” he said.
Maps built with out-of-date data can also result in homeowners at risk of flooding not knowing the threat they face.
FEMA is currently finalizing new maps for Fargo, ND, yet the maps don’t include any recent flood data, said April Walker, the city engineer, including from when the Red River overran its banks in 1997, 2009 and 2011. Those floods were the worst in Fargo’s history.
Fargo has more recent data, Walker said, but FEMA hasn’t incorporated it.
It’s unclear exactly how many new maps FEMA has issued in recent years are at least partly based on older data. While FEMA’s website allows anybody to look up flood maps for their areas, the agency’s maps don’t show the age of the underlying data.
FEMA’s director of risk analysis, Doug Bellomo, said it was “very rare” for the agency to digitize the old paper flood maps without updating some of the data. “We really don’t go down the road” of simply digitizing old maps, he said.
FEMA did not respond to questions about the maps for Fargo or other specific areas.
State and local floodplain officials pointed to examples where FEMA had issued new maps based at least in part on outdated data. The reason, they said, wasn’t complicated.
“Not enough funding, pure and simple,” Young said.
Using new technology, FEMA today is able to gather far more accurate elevation data than it could in the 1970s and 1980s, when most of the old flood maps were made. Lidar, in which airplanes map terrain by firing laser pulses at the ground, can provide data that’s 10 times more accurate than the old methods.
Lidar is also expensive. Yet as we’ve reported, Congress, with the support of the White House, has actually cut map funding by more than half since 2010, from $221 million down to $100 million this year.
With limited funding, FEMA has concentrated on updating maps for the populated areas along the coasts. In rural areas, “it’s sort of a necessary evil to reissue maps with older data on them,” said Sally McConkey, an engineer with the Illinois State Water Survey at the University of Illinois at Urbana-Champaign, which has a contract with FEMA to produce flood maps in the state.
When old maps are digitized, mapmakers try to match up road intersections visible on them with the ones seen in modern satellite imagery (similar to what you can see using Google Earth). But the old maps and the new imagery don’t always line up correctly, leading to what Alan R. Lulloff, the science services program director with the Association of State Floodplain Managers, called a “warping” effect.
“It can show areas that are actually on high ground as being in the flood hazard area when they’re not,” he said. “That’s the biggest problem.”