Over the past several months, Bob Jacobsen has been evangelizing for science.
In meetings with scientists, fellow engineers, even church leaders, he's preached the need for better data about the Amite River flood basin, information necessary to give people more accurate assessments about whether they could flood in the future. Some of his evidence is technical and plotted on logarithmic graphs or filed under titles like "river morphodynamics."
For lay audiences, there's a simpler chart punctuated by emoticons. Many residents — represented by a sunglass-wearing, smiley emoji — believe they're safe if they don't live in one of FEMA's high-risk flood zones, but as Jacobsen explains how people may be more vulnerable than the FEMA maps imply, the emoji begins to sweat, then grimace and finally redden in anger.
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Louisiana may be moving away from what Jacobsen sees as a potentially enraging system of categorizing who is at risk and who isn't. Staff with the Department of Transportation and Development are close to signing a deal with an engineering firm to create a powerful new hydrological model of the floodplain. Using new technology and computing power, the tool could run scenarios predicting how different storms will impact the basin and whether future projects could stem the tide or if a particular bit of new construction could make flooding worse. For that reason, there's hope it could make it easier for the state to petition the federal government for money to finish big, expensive projects like the Comite River Diversion Canal or the Darlington Reservoir.
However, if the tool is as advanced as experts hope — and they want features such as survey data gleaned from sweeping the basin with aircraft-mounted lasers — there's no local precedent for how it will be used. Agencies have already begun to jockey for control. Once the contractors turn the model over, LSU scientists want to maintain and update it. Jacobsen and other leaders at the Amite River Basin Commission, which is charged with reducing flood risk in the area, have argued forcefully that someone like them needs to be in charge of using the model to plan regional flood control measures and review large-scale projects that could affect the watershed.
And it's still unclear how the model could play into the ongoing lawsuit by residents and politicians in Livingston Parish who are suing DOTD over the Interstate 12 barrier they blame for worsening flooding in August. Former Walker mayor Rick Ramsey, skeptical of a DOTD-commissioned model, said Livingston officials have sought their own study of the flood to be performed by Rice University.
DOTD has remained quiet about the new model. Through a spokesman, the agency said it could not comment until a final contract is inked. The company they're negotiating with, Dewberry, did not return calls for comment. Sources familiar with the project estimated that the model could cost $1.5 to $2 million and take about 18 months to complete, depending on the terms of the deal and how much land will be modeled. Jacques Berry, spokesman for the Louisiana Division of Administration, said the money will come out of funds given to the state by the federal government after Hurricanes Gustav and Ike to lessen the impact of future floods.
Other states have done flood risk analyses of their own. California recently modeled ten Central Valley communities as part of a review of the regional levee system, explained supervising engineer Ricardo Pineda of the state's department of water resources. The model was able to show gradations of risk, rather than the stark 100-year floodplain used by the FEMA-backed National Flood Insurance Program. The NFIP divides the United States into two groups. The first includes people in the 100-year plain who have an estimated one percent chance of flooding each year. Their mortgages require flood insurance, but nobody else has to get it.
"We've got to get away from this 100-year in-or-out thing," Pineda said.
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However, the California model, with its additions like the 200-year floodplain, hasn't been adopted for any regulatory purpose, and federal officials recently told The Advocate that they have no plans to change the NFIP to account for new or different levels of risk.
In the past few years, as the NFIP has been modified, FEMA formed a new Technical Mapping Advisory Council. However, Luis Rodriguez, director of FEMA's Engineering and Modeling Division said the agency is primarily concerned with improving techniques to better define the 100-year floodplain, not adding in 50-, 300- or 1,000-year floodplains, as experts hope the new Louisiana model can produce.
For some people like Jacobsen, there's an interest in whether newer models could eventually be turned over to the insurance industry so private companies could write their own policies.
The general idea is that by combining information about storm frequency with property data, a user can calculate the annual value of flood insurance.
By the same principle, an entire community could predict the value of a new piece of infrastructure like a dam or reservoir by modeling how much water it would divert, how frequently it would be needed and how much property would be protected, converting the whole endeavor into dollars and cents. One sticking point for the Comite Diversion — which would redirect some river water into the Mississippi — and the Darlington Reservoir — which would retain Amite River water north of Central — is that the Army Corps of Engineers has decided that each project hasn't been beneficial enough to merit large investments over the years.
If the Corps has underestimated their value, the new basin model may give the state ammunition to refute their claims. The most common complaint has been that the federal government has not adequately accounted for development along the Amite River in the past several decades, particularly for the Darlington project, which was shelved almost 20 years ago but has resurfaced since last summer's flood. New homes and businesses have added to the value of property in the basin, and the cumulative effect of all the new buildings means that there are fewer open spaces for floodwater to drain, meaning it gets pushed into buildings instead, explained Amite River Basin Commission executive director Dietmar Rietschier.
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During the commission's February meeting, Rietschier said that while the agency is primarily known for its efforts to build the Comite Diversion it will have an opportunity with the model to take a new role in floodplain management.
"Modeling by itself has no value ... unless you have a process for how to use that tool," he said in an interview. "We need to look at this whole basin in unity."
He's called for the state to give the Commission more authority and funding to review projects that could have large-scale effects on flooding.
Whether to allow someone to build a single house, and maybe even a small neighborhood, would still be left up to local governments, explained LSU engineering professor Clint Willson. But if the state wants to expand a highway or build a new levee or make another big change, the plan would be to put it up to some regional authority to make sure it isn't going to cause more flooding down the road. Projects like large subdivisions or strip malls may qualify too, but details still need to be sorted out. The goal, Willson explained, is to ensure that upstream communities don't wash out folks who live downstream, and that property owners in the south don't bottle up too much water causing backups upstream.
"You can't put it in terms of parish. The water system doesn't work based on parish boundaries," the professor said.
Whenever a developer studies the flood impact of a new project, Willson said LSU wants to evaluate their findings and incorporate them into the model to make it more robust and keep it up to date.
He's in favor of appointing someone to use the new tool to regulate regional development, whether it's the Basin Commission, DOTD or some other agency, as long as they have the resources to fight flooding.
"You need to have a staff of people — a staff of engineers and scientists and planners ... who can use the tools to make a decision or evaluate these proposed projects quantitatively," he said. "We can't kind of dilly-dally. We can't. The people don't deserve that."