Isaac may have only made landfall as a category 1 hurricane, but torrential rains carried by the slow-moving storm have flooded large parts of Southern Louisiana and Mississippi and forced up to 50,000 people to evacuate from areas threatened by the badly damaged Lake Tangipahoa Dam on Thursday.

As NBC News reports, Louisiana officials ordered the evacuations earlier in the day fearing an imminent bursting of the dam, but later dialed down their language, saying that the instruction was given "out of caution." By late afternoon, engineers had begun a controlled release of flood waters downstream.

The levee system surrounding the city of New Orleans had been largely rebuilt by the federal government after its catastrophic failure during Hurricane Katrina seven years ago, and as Reuters reports, worked to the satisfaction of the U.S. Army Corps of Engineers and Louisiana Gov. Bobby Jindal. However, in the suburban and rural areas surrounding New Orleans where the levees and water pumps were not upgraded, massive flooding wreaked havoc on low-lying communities.

In Plaquemines Parish, which is Mississippi Delta country located at the toe-point of Louisiana, some residents found their homes under 12 feet of water after the downpour overwhelmed a levee. Plaquemines Parish has seen significant erosion over recent years, making its land more exposed to wind and water damage.

Other Southern Louisiana communities suffered similar fates. As Reuters reports:

"In Slidell, a town of about 27,000 people northeast of New Orleans, the surge from Lake Pontchartrain left the Eden Isle community under about a foot of water.

 

'You'd have never made me believe a Category 1 would dump this much water,' said Sam Caruso, 71, a former mayor of the town who was touring it in his pickup truck.

Emergency services rescued about 350 people from Slidell homes and neighboring communities hit by more severe flooding, local authorities said.

National Guard troops and police moved into the town Thursday afternoon as some local residents navigated flooded streets in boats. Overall, troops have rescued or evacuated more than 3,000 Louisiana residents and three tractor-trailer loads of pets, Jindal said."

Isaac also saw its first storm-related death Thursday, as a man in Vermilion Parish, La. fell from a tree while helping to move a vehicle, according to the Washington Post. While this is the first fatality, Isaac has exacted a much larger human toll, as thousands of people in Louisiana and Mississippi are currently homeless and large areas of the region remain without power in the sweltering August heat.

 

Read more of Neon Tommy's coverage of Isaac here.

Reach Executive Producer Matt Pressberg here.