Homes in St. James have begun to flood, and the worst may be yet to come, parish officials said Wednesday.

Both St. James and St. John the Baptist parishes are bracing for potential backwater flooding before the weekend, something that happens when rivers can't drain out into other bodies of water because of flooding elsewhere.

The area's Blind River normally drains through the Amite River. When more than 20 inches of rain fell in parts of East Baton Rouge and nearby parishes Thursday through Saturday, however, the water started to swell.

That caused a slow-moving disaster that officials said could eventually impact swaths of St. James and St. John.

Sandbagging efforts have been underway for days in both parishes, with more than 300 homes protected in St. James already. Despite those efforts, one home in the Grand Point community and another home in Gramercy, north of Hwy. 3125, took on a "minor" amount of water Wednesday morning, according to the parish's public information officer, Brandon Keller.

According to Keller, the good news is that the Amite River crested at French Settlement, an area that has the closest gauge available to the parish, and one the National Weather Service told officials to monitor.

Now, the water is expected to slowly recede in the Amite, meaning that the Blind River could soon start to drain away from local communities, too.

However, before it goes down, the water in the Blind River is expected to rise just a little more, Keller said. As of 2 p.m. Wednesday, the levels in that body of water were the same as those recorded during Hurricane Isaac, when about 40 homes flooded throughout St. James.

With Isaac, the parishes saw storm surge in addition to back flooding, Keller said, which made the situation worse. Still, he warned residents to be cautious, as water could continue to rise and flood homes through the night.

The National Weather Service issued a flood warning Wednesday for both parishes until 3:15 p.m. Thursday.

“The rise is very, very slow. We’re probably go to see a slow rise into tonight and tomorrow morning,” Keller said Wednesday afternoon. “We’re keeping posted on it. This is unprecedented.”

No flooding has been reported yet in St. John, but Natalie Robottom, the parish's president, also emphasized that flooding in surrounding areas has been unpredictable. On Wednesday, she said it was just too early to tell if the area's residents have avoided disaster.

Robottom's office said the National Guard was "pre-staging" vehicles and sheltering operations at the parish's community center Wednesday evening as a precaution, and that residents "should not be alarmed" if they see an influx of guardsmen or supplies.

Firefighters would continue to monitor and track water levels on roadways, outfall canals and lakes hourly, she said, and representatives from the state transportation department, National Guard, Red Cross and the Army Corps of Engineers were participating in preparedness operations.

She encouraged those with elderly family members to pay particular attention to local news and weather outlets.  

"We do not want our residents to be alarmed, but we do want you to be prepared should the event arise that we have to evacuate," Robottom said. "This is a very, very difficult storm to predict. The flooding event is difficult, there's a lot of uncertainty...there's just not a lot of information or historical data to tell us what's going to happen in our area."

Officials in both parishes are continuing to closely monitor water levels in the river and surrounding canals through the weekend, they said.

There were no evacuations taking place in either parish as of Wednesday evening, officials said, but shelters were ready and sandbag operations were continuing to take place.

Airline Highway (U.S. Hwy. 61) between La. Hwy. 641 and La. Hwy. 22 in Ascension Parish were closed Wednesday because of rising water along the highway. Businesses along Airline Highway between La. Hwy. 641 and La. Hwy. 3274 remained accessible from Airline Highway.

La. Hwy. 641 was also closed in both directions between I-10 and Airline Highway, as were the I-10 eastbound off-ramp and the I-10 westbound off-ramp to La. Hwy. 641. King Avenue in Lutcher was closed as well.

All roads in St. John remained open as of Wednesday evening.

All waterways on the east bank of St. James Parish will remain closed until further notice.

Schools in St. James Parish will remain closed Thursday, officials said. Schools in St. John will be open.

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