Hurricane Isaac came into the Gulf Coast weaker than meteorologists expected, as just a Category 1 hurricane, but the storm was strong enough to actually reverse the flow of the Mississippi River.
For close to 24 hours, the storm surge created by Hurricane Isaac actually caused water to flow up the river at a pace nearly 50 percent faster than the downstream flow, the US Geological Survey noted. As a result of the surge of water, the Mississippi River crested at 10 feet above its pre-storm height in the Plaquemines Parish southeast of New Orleans, the Christian Science Monitor reported.
The Mississippi River reversal was possible in part because of the hot, dry summer that preceded the storm. A long and far-spread drought in the middle of the country dropped the river to its lowest level since 1998, the Christian Science Monitor reported, making it easier for Hurricane Isaac’s storm surge to push water back the other way.
Hurricane Isaac had more traditional effects as well, Bloomberg reported. As the storm made it was out of Louisiana and into Arkansas, insurers estimated that it cost them as much as $2 billion.
The industry claimed that the costs of damage to residential, commercial, and onshore properties from the story will be at least $700 million.
“As the winds persist, roof fasteners and connections can become fatigued and overloaded causing additional damage,” Tim Doggett, AIR’s principal scientist, said in the statement. “With soils heavily saturated by rain, trees can be downed by much lower wind speeds than would otherwise be necessary.”
Though the number seems large, it would make Hurricane Isaac tiny compared to Hurricane Katrina in 2005. After damaging winds and flooding that overtook levees in New Orleans, Katrina caused an approximate $41.1 billion in damage.