Emergency crews launched airboats into submerged streets Wednesday to rescue central Florida residents trapped by rising floodwaters from a stalled Tropical Storm Fay, which soaked the state for a third consecutive day.

Meanwhile, Gov. Charlie Crist requested an emergency disaster declaration from the federal government to defray rising debris and response costs. Crist issued his own disaster order ahead of the advancing storm several days ago, when it seemed the Florida Keys would get the worst. Instead, Fay skipped almost harmlessly over the island chain, but stalled over the peninsula on a second swing through Florida. There, it has done the most damage.

On Wednesday, officials reported flooding in hundreds of homes in Brevard and St. Lucie counties, some by up to 5 feet of standing water. In three towns, rising waters backed up sewage systems. It wasn't immediately clear how many residents had been displaced or were stranded, but county officials reported making dozens of rescues.

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"We can't even get out of our house," said Billie Dayton of Port St. Lucie, as waters lapped at her porch. "We're just hoping that it doesn't rain anymore."

The Florida National Guard mobilized about a dozen guardsmen and some high-water vehicles to assist with damage assessment and help with evacuations, said Jon Myatt, spokesman for the Florida Department of Military Affairs.

The storm could dump 30 inches of rain in some areas of Florida and the National Hurricane Center said up to 22 inches had already fallen near Melbourne, just south of Cape Canaveral on the state's central Atlantic coast.

Forecasters originally expected Fay to energize over the ocean and possibly become a hurricane before landing in Florida for the third time later this week. The erratic storm first struck Monday, then veered out to sea before traversing east across the state, briefly strengthening, then stalling. The storm barely moved for most of Wednesday, dumping inches and inches of rain over coastal central Florida.

"In some areas, it's waist-deep," said Erick Gill, a spokesman for St. Lucie County. "We've had reports of people having 3 to 5 feet of water in their home."

Tom Christopher, St. Lucie County emergency management coordinator, said between 85 and 140 people were rescued by boat or high-clearance vehicle by Wednesday afternoon. He said no more were stranded, though other families seemed to be stuck without a way to leave.

Steve Grenon, 40, was sitting in the bed of his truck in front of his house. He said he'd been holed up there for two days, unable to leave with water was up to six feet deep in the street in front of him. A dodge sedan was partly submerged in front of him.

"I had no idea what it looked like out there until today," Grenon said.

The storm was 30 miles north of Cape Canaveral at 5 p.m. EDT Wednesday. Its maximum sustained winds were back up to about 50 mph and it was expected to resume slowly moving north later Wednesday at about 2 mph.

Gill said hundreds of homes had been flooded, though a count was incomplete. Homes also were flooded in Brevard County, said Bob Lay, the county's emergency operations director. Floodwaters also had caused sewage to back up, affecting another 40,000 to 50,000 people in three towns.

Fay formed over the weekend in the Atlantic and was blamed for 20 deaths in the Caribbean before hitting Florida's southwest coast, where it first fell short of predictions it could be a Category 1 hurricane when it came ashore.

Though no one in Florida had been killed, some were close. Joe McMannis, 27, said he jumped into floodwaters to help three people in a submerged truck in Jensen Beach. McMannis said the driver accidentally drove into a retention pond, confusing it for a driveway.

"I didn't think it was going to be that deep," he said. "It pretty much came up to my ears and chin. I saw this little kid coming toward me so I grabbed him and swam him back to the shore line and went back for other two guys that were still stuck in there."

The rain was welcome in dry Florida and Georgia cropland, but could also hurt farmers' production. Forecasters predicted parts of northern Florida could get 10 to 15 inches of rain, while southern Georgia could receive 3 to 6 inches.

"They're probably areas of the state that found the rains very beneficial. There are other areas of the state getting 10-12 inches that have crops in the ground and are getting too much," said Terence McElroy, spokesman for the Florida Department of Agriculture and Consumer Services.

McElroy said the rain could pool around and damage citrus trees and flood pastures and hay fields, but said it was too soon to quantify the damage.

Before moving east, the storm flooded streets in Naples, downed trees and cut power to some 95,000 homes and businesses. Tornadoes spawned by the storm damaged 51 homes in Brevard County, southeast of Orlando, including nine homes that were totaled. In the Keys, officials estimated 25,000 tourists evacuated.

In the Jacksonville area north of the flooding, officials prepared shelters and cleared drainage areas in anticipation the storm would jut left and drench residents there later this week. Public schools canceled Wednesday and Thursday classes, and mobile home residents were encouraged to find sturdier shelter.

In southeast Georgia, Camden County public works crews cleaned storm drains and ditches in preparation for possible flooding. The Georgia Emergency Management Agency also began 24-hour operations to monitor the storm.

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