Seven years after Hurricane Katrina battered Louisiana, the state is once again dealing with the forces of Mother Nature. Hurricane Isaac stormed into the Gulf Coast Wednesday morning, pushing water over the top of a levee in Plaquemines Parish just outside New Orleans.

As Isaac made landfall, it knocked down trees and cut power to more than 400,000 homes.

According to ABC News, there were no reports of injuries, but dozens of residents of Plaquemines Parish were stranded atop a levee, while there were multiple reports of people trapped in attics by rising waters.

"The water came up so quickly and overtopped the levees from Breakaway to White Ditch on the east back of the north end of the parish, President of Plaquemines Parish William Harold "Billy" Nungesser told Good Morning America. "It's an area that we called for a mandatory evacuation."

Nungesser also said that he has a four-by-four hole in his roof... and that the back wall of his house moved a couple of feet.

According to Nungesser, about 2,000 residents of the area had been ordered to evacuate but only about half were confirmed to have gotten out before Isaac made landfall late on Tuesday.

"On the east bank right now, we have reports of people on their roofs and attics and 12 to 14 foot of water [in their homes]," Nungesser told CNN. "This storm has delivered more of a punch than people thought."

Nungesser declared a state of emergency for the parish on Aug. 26.

New Orleans official have, however, noted that the category one hurricane did not overpower the $14 billion levees built to guard the city after Katrina.

"All of the levees are holding and are very strong," New Orleans Mayor Mitchell Landrieu told local radio.

Hurricane Isaac continues to wobble inland over southeastern Louisiana, with maximum sustained winds near 80 mph. Dangerous storm surge and the threat of flooding from heavy rains are likely to continue through Wednesday night. The center of Isaac will move over Louisiana on Wednesday and Thursday and over southern Arkansas early Friday.

Isaac killed at least 23 people and caused significant flooding and damage in Haiti and the Dominican Republic before attacking the tip of Florida on Sunday and heading across the warm waters of the Gulf of Mexico.

The Republican Party has had to share its spotlight with Isaac and had to rearrange the schedule of the Republican National Convention. Oil production in the U.S. Gulf of Mexico nearly ground to a halt and ports and coastal refineries curtailed operations.

Energy companies along the Gulf Coast refining center braced for the storm's impact by shuttering some plants and running others at reduced rates ahead of Isaac's landfall.

Intense hurricanes such as Katrina - which took out 4.5 million barrels per day of refining capacity at one point - have flooded refineries, keeping them closed for extended periods and reducing fuel supplies.

This time, though, the U.S. Department of Energy estimated that only 12 percent of the Gulf Coast's refining capacity had gone offline. Louisiana usually processes more than 3 million barrels per day of crude into products like gasoline.

Perceptions that the area's oil facilities would not sustain major damage, and that production would quickly bounce back, pushed international benchmark Brent crude down 74 cents early Wednesday, toward $111.84 a barrel.