LAPLACE, La. (AP) - The state sent scores of buses and dozens of high-water vehicles to help evacuate about 3,000 people from St. John the Baptist Parish after Tropical Storm Isaac pushed water from lakes Pontchartrain and Maurepas into parts of LaPlace.
Rising water closed off all main thoroughfares into the parish, which is about 30 miles west of New Orleans. In many areas, water lapped up against houses and left cars stranded. The water was being driven higher by south winds as Isaac passed to the west and was expected to continue rising through the night.
Floodwaters rose waist-high in some neighborhoods, and the Louisiana National Guard was working with sheriff's deputies to rescue people stranded in their homes and surprised by the flooding.
The floodwaters "were shockingly fast-rising, from what I understand from talking to people. It caught everybody by surprise," Lt. Gov. Jay Dardenne said.
By 8 p.m. about 1,500 people had been evacuated, most to a nearby church being used as a temporary shelter, and Gov. Bobby Jindal's office said up to another 1,500 more were expected to leave their homes.
Dardenne said officials speculated that the fortifying of levees in other parishes along Lake Pontchartrain after Hurricane Katrina forced storm surge into new areas that had escaped flooding in past storms.
"The water's got to go somewhere, and this is where it went," he said.
Jindal's top coastal adviser, Garret Graves, said he thought the theory was unlikely to be the cause of the extensive flooding.
"My personal opinion, based on the science, was if it did have any impact, it would be minimal," Graves said.
He said years of wetlands erosion has lessened the resistance to wave energy, allowing stronger storm surge to push farther inland. Also, Graves said even though previous storms like Katrina didn't inundate St. John the Baptist Parish, every hurricane has its own impact in areas surrounded by water.
"This one traveled slower, it had different wind, it had different surge. It was a different storm," he said.
The Department of Wildlife and Fisheries had 30 boats in LaPlace and 20 more on the way to get people out of their homes, and the state sent 89 buses to take them to shelters in Alexandria and Shreveport, and to evacuate an assisted living facility. The National Guard had seven high-water vehicles in the parish and another 25 -- as well as ten boats -- on the way Wednesday night to assist the parish evacuation efforts.
With one water district flooded, the National Guard also was sending two 5,000-gallon water tankers and 35,000 bottles of water to distribute to residents. State officials sending 200 one-ton sandbags to protect the water system from floodwater contamination.
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