BRADENTON, Fla. — Bob Johnson says the water in the canal behind his home of 22 years is usually swimming with fish and manatee until it mysteriously turned a dark, coffee-like color over the weekend.

“Got just like coffee,” Johnson said. “Real mucky looking.”

Johnson said it was his son who first noticed the discoloration Saturday when he went to take the boat out. He said the bottom of his boat looked like it had been sitting in toilet water.

“It was real noticeable,” Johnson said.

But it didn’t smell.

“No smell and I didn’t start coughing so I knew it wasn’t red tide,” he said.

The canals feed into the Sarasota Bay less than a quarter-mile away.

Johnson quickly scooped out a bucket-full of the water to set aside for testing and called the county.

A spokesperson for Manatee County told 10News they are ruling out a broken sewer line or sewage spill. 

Officials believe the discoloration might’ve been caused by runoff from nearby construction. The canal is less than a half-mile from a major construction project underway on Florida Boulevard.

Crews were out on Monday investigating.

Homeowners are skeptical.

“Is it going to go away?” neighbor Bruce Higgins questioned. “The last three months we’ve had red tide where you can’t go fishing and I mean, that’s the only reason we live here is to go fishing.”

While Monday night the discoloration showed signs of clearing, the cause continues to confuse.

“I hope they figure out what’s doing it,” Johnson said. “I don’t want it to come back like that, that’s for sure.”

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