Morganza, Louisiana (CNN) -- Residents of towns along the swollen Mississippi River were frantically trying to build levees and place sandbags to protect their homes Sunday as authorities opened two additional gates on the Morganza Spillway.
The move is aimed at sparing Louisiana's more populated areas from floodwaters -- but may still affect nearly 4,000 people living along the river as it sends water toward homes and farmland in the Atchafalaya Basin, according to Louisiana Gov. Bobby Jindal.
The U.S. Army Corps of Engineers opened two floodgates on the Morganza spillway Saturday, for the first time in nearly 40 years. Two additional gates were opened about 10 a.m. Sunday, the Corps said.
"At this time, we are currently monitoring the river but it is too early to know if additional gates will be opened today," Corps spokesman Ricky Boyett wrote in an
A collective gasp as Louisiana town braces for flood
Authorities in St. Landry Parish ordered a mandatory evacuation Sunday for about 2,000 people in areas of Krotz Springs and Melville. "By 5 p.m., everyone in the affected areas must be out," the parish said in a statement. Residents in some other areas were under a voluntary evacuation, with officials saying evacuation was encouraged.
Authorities plan to open as many as one-fourth of the spillway's 125 floodgates in the coming days in an effort to spare the Louisiana cities of Baton Rouge and New Orleans from severe flooding, Boyett has said.
"Really, we're just waiting," said Evie Bertaut of Morgan City, Louisiana, which sits on the banks of the Atchafalaya River. "Most people are getting their photographs together, things that you can't replace in case you have to go."
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She said she has lived in Morgan City for 50 years. Officials believe levees will protect the city from flooding, but some residents are taking preliminary precautions. At Sacred Heart Church, where she works, people have moved important documents such as marriage, baptism and financial records to the building's second floor, she said.
High water resulting from the opening of the spillway, about 115 miles northwest of New Orleans, could affect 3,900 people and 2,600 structures, Jindal has estimated. The Corps has said seven Louisiana parishes -- Pointe Coupee, St. Landry, St. Martin, Iberia, Iberville, St. Mary and Terrebonne -- will likely be affected. The spillway was last opened in 1973.
CNN iReporter Faisal Abou-Shahla posted a video of flooded homes in St. Francisville, Louisiana, about 30 miles north of Baton Rouge. He said he shot the video on Saturday, after the first gate was opened on the spillway. Abou-Shahla said he lives in Baton Rouge and was visiting his fiancee's parents in St. Francisville
"They're on a little bit higher ground, so there have been no (evacuation) orders given or anything like that," he said Sunday. "We're trying to talk them into coming over where we are in case the surrounding area gets flooded."
Some residents of St. Francisville tried to protect their homes, he said -- "there were a few seemingly futile attempts to put sandbags up." Some of those whose homes were seen flooded in the video were "waiting until the last second to leave," he said.
The spillway will likely be open for weeks, and it will be at least that long before those who have evacuated can safely return, said Col. Ed Fleming, the Corps' New Orleans district commander. It will take considerable time -- in some cases, weeks -- until the river falls back below the flood stage.
