Yanzanica Brumfield and her month-old son Za'Tayrian at a flood shelter in Kentwood, La. Residents evacuated after officials warned that a dam upstream in Miss. was in danger of bursting due to rains from Isaac. (Photo by John Moore/Getty Images)
Ruthie Pearl Clark, 65, waits outside a flood shelter set up at the Kentwood High School in Kentwood, Louisiana. (Photo by John Moore/Getty Images)
The Percy Quin State Park dam shows deterioration that has threatened the dam's integrity. / US Army/Special to The Clarion-Ledger
New arrivals check in to a flood shelter set up in a high school gym in Kentwood, Louisiana. (Photo by John Moore/Getty Images)
Clarion-Ledger, Jackson, Miss. and USA TODAY
Officials began releasing water at a lake dam that threatened to break near the Louisiana-Mississippi border, flooding a rural area, as Isaac weakened to a tropical depression on Thursday
Louisiana Gov. Bobby Jindal is urging residents to evacuate who live a half-mile on either side of the swollen Tangipahoa River, which could further flood if the dam at Percy Quin State Park gives way.
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The fragile dam, stressed from the high waters brought by Isaac, has not failed, Jindal said, but an evacuation will help safeguard lives should that happen.
The dam in Pike County near the Louisiana state line is in imminent danger of failing, which could send 17 feet of water to Kentwood, La., within 90 minutes, Jindal said in a press briefing.
Engineers and other officials are working now to complete a controlled breach of the dam, allowing about eight feet of water to spill over into Lake Tangipahoa, a 700-acre lake at the dam. The river flows south into Louisiana, and failure of the dam could send a torrent of water into that state and the city of Kentwood.
"My message to the people of Tangipahoa Parish is, take your evacuation seriously," said Jindal, flanked by about a dozen city and county officials. "We don't want people to wait. It takes 90 minutes for that water to get to the state line in Louisiana."
The dam is being breached and drained slowly to release enough water to take pressure off the dam.
"Let's prepare for the worst, even though we hope for the best," Jindal said. "That's much better than being in your home and having to be rescued because the dam fails and the water rises."