For months, the levees in eastern Nebraska and western Iowa held back the rising waters of the Missouri River.
But now, two years after the long flood, those levees are in trouble, and taxpayers are caught either way.
Unless local managers can prove to the federal government that the protection is adequate — at significant cost — development in parts of the Omaha-Council Bluffs metro area could stall, part of Offutt Air Force Base could be placed in a flood plain and many homeowners could be faced with having to buy flood insurance.
Some 75 miles of levee in Council Bluffs, southern Sarpy County and Mills County, Iowa, are at risk of losing their accreditation when the Federal Emergency Management Agency updates its national flood insurance maps. This would reassign a big chunk of locally important areas to the flood plain.
Local levee managers say the new accreditation studies are expensive and the repairs more so, potentially costing tens of millions of dollars. Local officials say that work is unnecessary — the proof the levees are in good shape came during the flooding of 2011.
“It's a mess,” said Greg Reeder, public works director in Council Bluffs. “The first thing we said after the 2011 (flood) was 'What more proof do you need?'”
Council Bluffs has 28 miles of levee protecting the city from the Missouri River, Indian Creek and Mosquito Creek. All of it needs to be reaccredited.
“We know we have some significant challenges on all of them,” Reeder said.
If that doesn't happen, FEMA will draw its flood insurance maps as if the levees weren't there, putting about two-thirds of the city in the flood plain.
FEMA did not return multiple calls for comment. But on its website, the agency says the new standards simply ensure that people have accurate, timely information about the levees protecting them.
“Although FEMA's current procedures are technically sound, FEMA recognizes the benefits of a more precise modeling approach to determine flood zones and establish insurance rates,” the agency says.
Levee sponsors across the country have known about the problem for some time. After FEMA issued new guidelines for its flood insurance maps in August 2005 — as Hurricane Katrina was forming over the Bahamas, coincidentally — levee sponsors began getting letters that gave them a two-year deadline to prove their levees met the certification standards.
For Council Bluffs and the Mills and Pottawattamie Counties levee district in Iowa, that deadline finally hits next month.
But it's not as simple as mailing in paperwork, Reeder said. The city had to pay $1.1 million for an engineering study to quantify the problems, and officials expect to spend up to $20 million over a period of years to fix any deficiencies.
Meanwhile, Reeder said, it's likely FEMA will begin the de-accreditation process. The agency can take at least 18 months to remove a levee system's accreditation, and sponsors can submit engineering data any time to halt the process.
Another possibility: FEMA is considering a special flood insurance zone for levees that have performed well in major floods, even if they don't meet the new standards, Reeder said.
Part of the issue is that the two federal agencies with an interest in flood protection — FEMA and the Army Corps of Engineers — emphasize different things, said John Winkler, general manager of the Papio-Missouri River Natural Resources District. The corps focuses on engineering standards; FEMA looks at risk management. And sometimes they draw different conclusions from the same evidence.
“The corps could say that this is a good levee, and it meets our standards,” he said. “But FEMA can come in and say 'Well, it doesn't meet ours, and you need to prove it.'”
In any case, Winkler said the district's levees are structurally sound, and they're maintained constantly throughout the year.
FYRA Engineering is working with the district to re-accredit 18 miles of levee, and the levee work is expected to cost taxpayers between $15 million and $20 million.
The levees are between 11 and 12 feet tall. In some places they will need to be raised a few feet; in others, not at all. The project will require hundreds of thousands of cubic feet of soil to keep the slope intact and a geotechnical review to address berm seepage and other issues, said FYRA engineer Michael Sotak.
“Nationwide, local sponsors are figuring out very quickly that levee certification is expensive,” Sotak said.
The levees were built by the corps in the 1960s to withstand a 100-year flood. But FEMA changed how it models the Missouri River's flow, raising the base flood elevation, and Omaha's continued expansion is changing the watershed's hydrology. More roads, buildings and parking lots mean less permeable ground to soak up rain and snow, and eventually all that water sluices down to the Missouri River like a giant funnel.
“These levees won't meet those (new) standards,” Winkler said.
That would place some important areas — including Offutt Air Force Base, the Papillion Creek sewage treatment plant and land slated for development around the Highway 34 project — in a flood plain.
For Offutt, “that would pretty much eliminate the base's ability to seek any new missions,” Winkler said.
Offutt spokesman Delanie Stafford said in an email that base commanders haven't received an official communication about the levee problems, so he couldn't comment on that process.
“We can tell you that if FEMA decertifies the levees around Offutt and the base ends up being in a federal flood plain, it would significantly impact the south side of the installation,” he said.
The NRD expects to get its letter from FEMA soon. District officials will get an update Tuesday on the status of a preliminary engineering study that will give them a better idea of the extent of the work required.
Mills County's certification deadline is next month.
Larry Winum, president of the Mills County Economic Development Foundation, said county officials have been talking with FEMA about an alternative review process.
If nothing can be worked out, though, the economic impact of having unaccredited levees could be significant. Crop insurance rates probably would rise. Anticipated development along the Interstate 29 corridor — especially at a new Highway 34 interchange — could evaporate if new flood insurance requirements complicate business financing.
But Winum was upbeat.
“I'm still optimistic that we'll get something worked out,” he said.
The 13 miles of levees managed by the City of Omaha will have to be recertified, too, but they were built to withstand a 500-year flood event. So most of the work will focus on relief wells, underseepage studies and pipe penetration through the levee, public works official Gordon Andersen said.
“Omaha, fortunately, is in a bit better situation,” he said.
Omaha expects to get its letter from FEMA this year. To stay ahead of the curve, Andersen said, the city has been working with the corps to interpret the flood data, and it will soon issue a request for proposals for an engineering firm to guide the recertification process.
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