MORGAN CITY — The city’s fight with the Federal Emergency Management Agency regarding the city’s appeal of the government agency’s flood maps for the area appears to be coming to a close.
During Tuesday’s monthly meeting, Mayor Tim Matte told the city council that the latest curveball FEMA has thrown at the city in its fight to protest what it considered flawed data in FEMA’s model runs has been challenging to counteract.
Instead of continuing to fight what could be a costly venture with a dwindling bank account to finance the actions, Matte said the city is content on receiving the heights it needs to raise its levees to keep its base elevation heights the same, if it is financially feasible. Doing so would allow the levees to be certified.
Lucien Cutrera of LCJ Poole in Baton Rouge, one of numerous consultants the city has working on its behalf in the appeal, explained the latest challenge, which FEMA said is a wind-induced “tilt” in the water as it moves closer to the shoreline at Lake End Park. The tilt, similar to a tidal wave, reaches as much as 8 feet by the time it arrives at the park.
“It’s really whipping us (in this FEMA appeal),” Cutrera said of the tilt.
The phenomenon, which occurs in a Florida lake, was discovered when Matte asked FEMA to run the three worst hypothetical storm models it has in its arsenal for the area.
To determine the potential 100-year flood scenario for a particular area, FEMA runs 40 storm models through that area to produce the proper base flood elevations for building houses and businesses in Morgan City. Current base flood elevation requirements of +2 feet were instituted in May 1996.
While the worst storms show the lake levels remain at two or three feet above its normal levels, they show this tilt occurring halfway through the lake, which has a five-mile radius.
It “doesn’t happen,” Cutrera said. “We know that.”
Still, Matte said the city has expended nearly all of the roughly $140,000 it allocated for its FEMA appeal, and challenging the tilt could be a costly venture with little benefit.
While flood modeling and wave expert, Dr. Joe Suhayda (one of the city’s consultants in its appeals process), has said wind can drive water during a storm surge event, but that it is unlikely that it would be to the extent FEMA said, Matte told the council.
Therefore, the city is willing to raise its levees, if possible, to a height that allows them to keep their BFEs the same.
The mayor said he expected to have the BFEs by the end of August or early September. Currently, the BFE is +2 feet and as of now, FEMA is asking for a +7 foot BFE for property that is protected for the levees in question, which average between 7 and 8 feet.
However, if the city raises its levee heights by a certain footage, it can keep the same BFEs.
While the most debated model locally has been FEMA’s modeling of Hurricane Rita’s effects on the area — FEMA’s models show flooding while city officials said none occurred — Matte said the city has been able to close some of the gap with data and gauge levels that differ between the city and FEMA.
If this is the end of the fight, it would close a battle that began approximately three years ago when FEMA announced the city’s backwater levee system needed to be at 10 feet mean sea level rather than the existing, U.S. Army Corps of Engineers-approved 8 feet.
The finding put a damper on plans to develop the city’s first subdivision in more than three decades.
The city already has scraped together $12 million from various sources for the levee improvements, some of which the city has always agreed need to be made.
When the accurate base flood elevation is determined, Matte said the city would know how much to raise affected levees and then could determine a total project cost.
Current predictions are that it could be as much as $16 million to comply with acceptable, new FEMA flood elevation maps.
At the beginning of the decade, city officials said Consolidated Gravity Drainage District 3 — which includes all of the city, plus some neighboring areas — did work on the levees to raise them to the level necessary for a projected 100-year flood.
“I have not had the expectation that there is no work that the City of Morgan City or the drainage district needed to be done on (these levees),” Matte said.
Since FEMA’s announcement in 2008, the city and FEMA have been at odds about what happens with water flow in Lake Palourde, particularly when comparing FEMA’s models of what happened in Hurricane Rita as opposed to what the city documented during the 2005 storm.
While city leaders have argued that the water in Lake Palourde continues to flow north into a vast area during hurricanes and storm surge events, FEMA previously believed that a barrier in Bayou Boeuf kept the water from continuing to flow into the Pierre Part area.
However, earlier this year, FEMA recognized there is no barrier in this area and water did flow north into this vast area encompassing hundreds of square miles to Pierre Part.
That means, city leaders have argued, that water levels in Lake Palourde should be the same as these backwater areas, meaning water levels throughout these areas must be the same.
Suhayda said that when water reaches 2.5 feet in Lake Palourde above its normal levels, there is enough force to push it in these areas north of Morgan City.
According to Suhayda’s calculations, flood protection should be based on an elevation of no more than 5 feet in Lake Palourde under the flood circumstances presented by FEMA.
He said the flattening across that vast basin of waterways once water levels reach 2.5 feet is significant. That, Matte said, makes him believe that waters in Lake Palourde would never reach 6 feet during any of those storms that FEMA is running models for.
Earlier this year, the city received official documentation and extensive maps documenting FEMA’s understanding with more of the city’s concerns than it initially agreed upon.