St. James Parish is bracing for the possibility of backwater flooding that could infiltrate homes and force more evacuations amid historic flooding that already has killed at least seven and displaced thousands more.

Volunteers are needed at all sandbagging locations in the parish to help brace for the potential flooding, officials said Tuesday. So far, more than 500 volunteers have filled more than 50,000 sandbags, according to the parish's public information officer, Brandon Keller.

Parish officials are on high alert at least through Saturday because the Blind River, which runs through the parish, normally drains through the Amite River.

But when more than 20 inches of rain fell in parts of East Baton Rouge and nearby parishes Thursday through Saturday, the water started to swell in local rivers, creeks and waterways. The result has been a slow-moving disaster.

The weather has caused six rivers to hit record levels in Louisiana. Among them is the Amite, which surpassed its previous record by over 6 feet in Magnolia and by over 4 feet in Denham Springs, according to the Weather Channel.

And the water is still moving, officials said, meaning that the Blind River is backed up and has nowhere to go but out into marshes, swampland and perhaps communities in St. James Parish.

"At this level, at this time, we’re being very cautious," Keller said. "This is a record-breaking event."

Keller pointed to Hurricane Isaac as reference, noting that about 40 homes were impacted in St. James Parish from back flooding caused by that storm.

Because of the nature of this flood, Keller said, officials "assume" about the same number of houses could be damaged. So far, he estimates that fewer than 100 homes would flood if the water doesn't go down soon, but he emphasized that officials were still "closely monitoring" the forecast.

"No two situations are the same, but we want everyone to do what they can to prepare and mitigate any damage in case," he added.

The water isn't expected to crest until Thursday or Friday, Keller said, so high water around St. James will be monitored through the weekend. So far, areas north of La. 3125 are at the greatest risk, including portions of Gramercy, Lutcher and the community of Grand Point.

No evacuations have been ordered so far, and there are no shelters in St. James Parish open. The Entergy substation has been protected with Hesco baskets, and the company is monitoring the site 24 hours a day, officials said.

Several roads have been closed until further notice, including Airline Highway (U.S. 61) between La. 641 and La. 22 in Ascension Parish, and King Avenue in Lutcher.

All state government offices in St. James Parish are also closed. That includes the Office of Motor Vehicles, the Registrar of Voters, the Health Unit and the Business and Career Solutions Center. Jury duty in St. James Parish was canceled for Tuesday. 

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All waterways on the east bank of St. James Parish are also closed to recreational boat traffic until further notice. 

Classes were canceled in public schools and at the St. Peter Chanel Interparochial School.

Sandbagging will continue to take place daily from 9 a.m. to 9 p.m., officials announced. Sand and bags for sandbagging are available at the following locations:

East bank locations:

• Grand Point Fire Station

• Behind Creole House Restaurant

• Young’s Kwik Stop in Convent

• First Community Antioch Baptist Church

• Gramercy North Airline Highway Fire Station (Near St. James Nursery)

West Bank locations:

• King View Street Fire Station

• South Vacherie Fire and Rescue Training Center (Near Health Unit)

Residents are encouraged to bring shovels and go to all locations in order to fill as many sandbags as possible.

Updates will be posted throughout the week and weekend on the St. James Parish website.

Follow Della Hasselle on Twitter, @dellahasselle.