Flood risk exists on both sides of levees
As recent research at the University of California, Berkeley confirms, Americans protected by levees are unaware of the true risks they face.
By: Jessica Ludy, Grand Forks Herald
DELFT, The Netherlands — The Herald’s editorial about flood insurance struck a chord that resonates from Grand Forks to Stockton, Calif. (“Flood-risk map stretches from coast to coast,” Page A4, Sept. 7).
Here’s hoping it reverberates in Washington, too, as lawmakers debate reforms to the National Flood Insurance Program.
As the editorial accurately warns, “being at low risk is not the same as being at no risk,” though the NFIP might lead us to believe otherwise.
As recent research at the University of California, Berkeley confirms, Americans protected by levees are unaware of the true risks they face. This may account for the more-than-86 percent of Americans (as mentioned by the editorial) who should buy flood insurance but choose not to.
Here’s the issue: The treatment of lands protected by 100-year levees under the National Flood Insurance Program has had the unintended consequence of putting more people in harm’s way without their knowing it.
Plus, it increases American taxpayers’ liability when a disaster occurs.
Under the NFIP, a house in a “100-year” floodplain is considered to be in a Special Flood Hazard Area. If the community participates in the NFIP, and the property is secured by a federally backed mortgage, the property must be covered by a flood insurance policy.
Furthermore, new construction or significant modifications to buildings require elevating structures above Base Flood Elevation — the height that water is expected to reach during a 100-year flood.
Meanwhile, on the protected side of a levee, homes are officially “out of the floodplain” — a potentially fatal flaw of the NFIP.
Here, there are no flood insurance requirements nor are there obligations to “floodproof” a building. Land below sea level also falls under this category, as long as it’s behind a 100-year levee — and even if it would be 10 feet underwater after a levee break.
Given these vital NFIP distinctions, one might think levees remove all risk. So, why would one buy insurance? Why elevate a house?
If we’re not allowed to smoke in public places or drive without a seat belt, why would we be allowed to do other “unsafe” activities?
Of course, the trouble is that lands behind levees can and do get flooded by floods higher than the levee. And in fact, this residual risk is quite high: 26 percent over a 30-year mortgage.
Accounting for possible human error and levee failures, that chance is 78 percent.
Why is this important? If officially “in a floodplain,” people are more aware that they can be flooded because they must comply with NFIP requirements. But what about people behind a levee: people “out of a floodplain” who don’t know that their houses were 10 feet underwater within the past 15 years (as is the case in so many new subdivisions behind levees along the Mississippi river or the Sacramento-San Joaquin Delta)?
In 2009, we surveyed residents of Stockton, Calif., in a new subdivision below sea level. We found that residents mostly considered themselves to be at low or no risk of flooding.
They had not been told of their residual risk. In fact, some who asked their real-estate agent even were told that they were risk-free.
Confirming the editorial’s remark that “too few” of those at risk have flood insurance, only 20 percent of respondents reported buying a policy, and only 13 percent took any preparation measures whatsoever.
Most residents believed levees would protect them from all floods.
Even more to the point, they believed the government would not have let them live there if it were not safe.
In discussions on floodplain development, the most common argument is, “There is risk everywhere: earthquake, fire and so on. So, why regulate floodplains?”
Floodplains are different, that’s why. In earthquake zones and wildfire-hazard areas, homeowners are required to retrofit houses to be earthquake- or fire-resistant. But land behind levees officially is considered hazard-free and requires nothing to be compliant with the NFIP.
A reformed flood-insurance program should prioritize public safety and taxpayer liability by removing incentives to developing in floodplains — especially deep floodplains.
It should provide better information on flood risk to residents before real estate transactions and require insurance and building modifications behind levees that reflect the true risk.
Insurance rates and building elevations should increase with the expected depth of floodwater if a levee failed.
In short, a truly reformed national policy should officially recognize and communicate that land behind levees will be what it always has been: Floodplain.
Ludy is a Fulbright Fellow in flood risk management, now studying at Delft University of Technology in the Netherlands.
She conducted her California research while a graduate student at the University of California-Berkeley. She was helped in this research by G. Matt Kondolf, chairman of the Department of Landscape Architecture and Environmental Planning at Berkeley.