Bellevue officials now say a 4-foot-high flood of stormwater and motor oil in Factoria earlier this month cannot be blamed on storm-drain filters, contradicting what a city spokeswoman first said.

Hoping the city helps pay for the damage, at least one business owner is skeptical about the city changing its account of what happened.

Flooding during a downpour on the night of Aug. 12 and the morning of Aug. 13 damaged at least two Factoria businesses and seven condominiums. The backup near Formula-1 Fast Lube made an especially big mess in the 3600 block of Factoria Boulevard Southeast when oil from an underground pit floated up into the stormwater backup.

At the time, city of Bellevue spokeswoman Tresa Berg said the backup near the oil-change business quickly receded after crews removed filters from at least one stormwater drain. She said the catch-basin bags, which help keep debris and other pollutants from entering stormwater drains, were recently used along Factoria Boulevard Southeast because of repaving work.

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The city now says the flooding was caused by a rare downpour that overwhelmed the drainage system and that floodwater receded gradually. The storm-drain filters, the city said, had been removed about two weeks earlier.

The 10-hour storm, which broke rain records throughout the Seattle area, dumped 2.75 inches of water near Factoria, according to the city’s Interstate 405/Coal Creek rain gauge.

Berg said information about the filters was relayed to her by city staff the day of the storm.

“At the time, that’s what they understood happened,” Berg said. “But I don’t know if they saw that work or just said that based on what they were told at the scene.”

The city’s storm-drain system is designed to handle a 100-year storm event, and it managed the rare intensity of the recent downpour as well as it could have, said city spokeswoman Emily Christensen.

Handwritten work-log notes show that crews were tasked with taking out the drain filters at the end of July.

Bob Healy, owner of Formula-1 Fast Lube, said he’s worked at the same location since 1985 and never saw the area flood anything like it did Aug. 13. None of his employees saw the backup, which crews responded to around 4:30 a.m. But he said people at the scene told employees it took about 10 to 20 minutes for the water to recede after something was pulled out of the drain.

“I believe that they did leave the bags in the drain,” Healy said. “Why did the water drain so quickly if they didn’t pull something out?”

KIRO reporter Jeff Dubois told The Seattle Times he saw the backup recede rapidly after city workers pulled something out of a drain, but didn’t know if it was a filter or a collection of debris.

Healy plans to submit a damage claim to the city after he receives all invoices from businesses that helped clean up and drain oily water from his shop.

Bellevue is currently reviewing its liability for one residential damage claim related to the storm, but it’s for a home outside the Factoria area, Christensen said.

Alexa Vaughn: 206-464-2515 or avaughn@seattletimes.com. On Twitter @AlexaVaughn