Neighbors ask, 'Why did we flood?'

Don Duplantier rolls a pirogue away from his flooded home in Scarsdale on the east bank of Plaquemines Parish on Sunday (John Snell)
Don Duplantier rolls a pirogue away from his flooded home in Scarsdale on the east bank of Plaquemines Parish on Sunday (John Snell)

Braithwaite, La. -- In flooded towns from Plaquemines Parish to LaPlace, many residents blame the new levee system for last week's flood.  Water poured into neighborhoods that had been spared in Hurricane Andrew, seven years earlier to the day.

While the Obama administration vows a quick, independently reviewed study of the causes, experts say Hurricane Isaac also drives home the fact that tropical systems cannot be judge by category number alone.

Size, path and duration all play into the destructive force of these killer storms.  Those other ingredients help to explain why some areas were forced to fight more water this time than even in Hurricane Katrina seven years earlier.

Conversely, areas south of Houma, which had flooded catastrophically in past tropical storms, came through Isaac relatively unscathed.

Long before making landfall, FOX 8 meteorologist Chris Franklin explained Isaac was "piling water into Lake Pontchartrain."  Franklin says speed figured into the equation, as Isaac stalled before slowly creeping up the Mississippi River.

As the storm was making its first landfall near Grand Isle, Franklin said "winds were still coming in from the east."

Even as Isaac zigzagged off the northwest, the winds drove more wore water toward Laplace near the western end of Lake Pontchartrain.

"It's not until the winds are well to the north that you finally get the backside of the storm and it's more of a northerly and westerly direction," Franklin said.

By sheer volume of water, experts say Isaac was no match for Katrina.  The early estimates suggest Isaac's surge came to roughly the roof line of a one story building, 10 to 12 feet.  Katrina sent a wall of water nearly 3 stories high, plowing into the Mississippi Gulf Coast.

"I tell you what, they ought to quit rating these hurricanes and just call them hurricanes," said Don Duplantier, an East Plaquemines resident as he surveyed his flood-ravaged home on Sunday.

While Katrina was a fast-moving storm, the smaller Isaac crawled along the shoreline, pumping water into rivers, bays and lakes for two-and-a-half days.

"If I learned anything -- if it's a storm, it's a storm and don't put a number on it,"  said Duplantier.

Like many of his neighbors in the Braithwaite area, Duplantier is convinced the giant new flood walls protecting much of metropolitan New Orleans funneled water into his neighborhood.

In LaPlace, Alvin Gaubert echoes the sentiment.

"This was so fast, it's like something happened that was different," Gaubert said.  "Something was different."

In LaPlace Monday, President Barack Obama promised a quick review of whether the new post-Katrina storm defenses poured water onto others outside the system.

The U.S. Army Corps of Engineers points out the new flood walls have the same footprint as those pre-Katrina.  The Corps says its Vicksburg, Miss. computer center conducted 150,000 model runs to determine the path that water would take in different hurricane scenarios.

While Corps leaders have expressed doubt that the new study would find anything different, they have vowed to conduct a new study that will be peer-reviewed.

Senator Mary Landrieu told the Associated Press she expects the study to be complete within two months.