The brown, oily water that started to flood Chapman Avenue in Bonita Springs earlier this week was a safe distance away when Jack and Virginia Guffey left their home on the quiet road Monday morning.

That changed when they returned two hours later.

"Went out of here with no problem," said Virginia Guffey, 60. "Came back and barely could get back in."

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The standing water rose, flooding the backyard and splashing into the couple's house through the front and back doors.

On Thursday the couple started to clean their drenched home. Water residue was splattered on the wood floors. Virginia Guffey used a shop vacuum to suck some of the water from a bedroom.

"And the more you clean, it just keeps coming back," she said.

Their backyard was still underwater Thursday. A dark mark along their fence showed how high the water had once reached. Sandbags walled off the front door, but they, too, failed to stop the water's intrusion.

"It has just wiped us out," Virginia Guffey said.

The Guffeys, who own their home, said they have lived on Chapman Avenue for about three years. The house is paid off, Virginia Guffey said.

"We don't owe for this one," she said.

The couple lacks flood insurance on their house but said they plan to remain in the home.

"We're going to try to fix it up," Virginia Guffey said. "There's no way we could try to sell it and live somewhere else. We're pretty much stuck here."

Federally regulated or insured lenders must require flood insurance on mortgaged properties in areas at high risk of flooding, according to the Federal Emergency Management Agency. Homeowners without mortgages are not required to buy flood insurance.

Bonita Springs City Manager Carl Schwing said the city has no knowledge of how many homes near Quinn Street lack flood insurance.

But he said the area, which includes Chapman Avenue, is known to be prone to flooding.

"It's basically shaped like a bowl," he said.

The middle area of the "bowl" takes on water first and reaches the highest water levels, but the surrounding areas get wet too, Schwing said.

After heavy rains that started last week saturated the ground, the Imperial River, which flows just north of Chapman Avenue and Quinn Street, topped its banks.

The water had nowhere to go, Schwing said.

The last major flood in the city was in 2008, Schwing said.

But the most significant one was in 1995, about four years before Bonita Springs became a city.

"In 1995 the river reached a level of 13.2" feet, Schwing said, referring to the Imperial River. "On Tuesday of this week, the river hit 13.21."

Since then, water has started to retreat in most areas, Schwing said.

By Thursday the Imperial River's water level had dropped to 12.94 feet, and the drainage system started to rid some streets of the excess water, he said.

Lee County crews have begun to assess flood damage and were about 80 percent done by Thursday, said Betsy Clayton, a spokeswoman for the county.

Bonita Springs is starting to look for ways to pump some of the excess water into ponds or flow ditches that can hold additional water without creating new problems — something that was not possible earlier this week, Schwing said.

"We're going to be looking for these opportunities," he said.

But total relief from flood risk might be impossible, the city manager said.

"It's very, very difficult, practically speaking, to raise homes or raise the entire development," he said. "It's just a bad situation."

A few areas, including Quinn Street and Chapman Avenue, remained under knee-high water Thursday afternoon.

On some roads — including Edith Lane and Downs Drive, which are just east of Quinn Street — it is difficult to assess whether the water level has lowered, Schwing said.

"We are having to play the waiting game," he said. "Water recedes a lot slower than it floods."

Help line

To report flooding or ask for help, call the United Way help line at 211.