Flood defences in New Orleans were strengthened

GOOD MORNING AMERICA

Heavy rainfall from Tropical Storm Isaac is threatening a dam in southern Mississippi, leading local officials to order an evacuation.

Mississippi emergency management notified Gohsep and Tangipahoa Parish, La., government of an "imminent failure" of the dam at Lake Tangipahoa in Mississippi's Percy Quin State Park, which is expected to cause additional flooding along the already swollen Tangipahoa river. The park and dam are near the Louisiana border, reports Good Morning America.

The Department of Environmental Quality, looking to relieve the pressure of the dam, may instead continue sandbagging the area or pump water over the dam into the agriculture surrounding areas.

About 19 to 20 families one mile on either side of the river have been ordered to evacuate, Louisiana Gov. Bobby Jindal said, adding that Mississippi authorities may execute a controlled breach of the dam.

Gordon Burgess, President of Tangipahoa Parish in Louisiana, ordered residents who live near the dam to evacuate by 1:30 p.m. ET.

McComb, Miss., Mayor Whitney Rawlings said that the dam is still holding, but the major concern is that it may fail. McComb said there is currently a 50 percent chance the dam will fail.  Mississippi officials said they don't think the volume of water in the 700-acre lake would add enough flow to the river to cause major flooding, according to The Associated Press.

The town of Kentwood, Miss., is expected to be hit with flooding first. EMA Operations Manager Richard Cogland at Percy Quinn Lake says they are lowering the lake level but that the dam is currently still holding.

The evacuation advisory from the Louisiana Emergency Management Agency ordered that "all low lying areas and along the Tangipahoa river" be evacuated due to the potential failure of the Percy Quin dam. A precautionary evacuation of the area south of Lake Tangipahoa in Pike County has been issued by the Pike County Emergency Management Agency.

Engineers from the Mississippi Department of Environmental Quality and officials from the Mississippi Department of Wildlife, Fisheries and Parks are assessing the damage at the structure in Percy Quin State Park, according to Mississippi Emergency Operations Centre.

As Isaac moves away from New Orleans, the storm is surrounding areas of Louisiana and spinning off tornadoes across Mississippi and Alabama.