CHICAGO — What's that brown stuff leaking into the river near the Michigan Avenue Bridge?

Around 9 a.m. Thursday, brown fluid began leaking into the Chicago river near the northeast corner of the Michigan Avenue Bridge, just below Pioneer Court.

A city spokesman said a department of water management investigation determined that rust and dirt inside a stormwater runoff outlet near the bridge spilled into the river following torrential rains. The spokesman said the city is working with the Metropolitan Water Reclamation District to draw water samples and further determine the source of the "rust-colored plume."



Sarah Carson/DNAinfo

Tiara Epps, who has been working for Chicago's First Lady river cruises about a year, may have pre-empted city officials Thursday morning with her theory that the brown water was rust. At approximately 9 a.m., she saw the brown stuff was even "bubbling" in the river.

"It looked like something was chipping off [into the river]," Epps said. "We were like 'what in the world?'"

Mauricio Peña is on the case:

Though alarming to some, the brown stuff did not dissuade tourists from enjoying the riverfront Thursday. Rocio Ezquerra, who was visiting from Spain, said she's accustomed to brown rivers.

"Yes, really," she said. "It's normal when there's rain and sand from shores [spills in]."

Karen Smith, a tourist from Scotland taking photos on the Michigan Avenue bridge, said she sees the same with rain-driven mudslides.

Just last month, the river was dyed green for St. Patrick's Day. The river's brown hue made one man who works for Shoreline Sightseeing raise an eyebrow, but it wasn't the first time he'd seen the river turn brown.

"Like 40 years ago ... the river always looked like that," said the man, who declined to give his name. "Maybe there's a new holiday we don't know about."

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