By Audrina Bigos

CHICAGO (CBS) — Crews battled a very smoky fire underneath Lake Shore Drive on Monday.

The smoke was so bad, Lake Shore Drive was shut down in both directions.

CBS 2’s Audrina Bigos has more.

They worked on it for hours and CBS 2 was told the last time a piling caught fire it burned for three days. At one point there was zero visibility. From all angles, you could see the heavy smoke at the Lakes Shore Drive Bridge over the Chicago River.

Traffic stopped because drivers and crews couldn’t see. Walking paths and bike paths were also closed. And boats were stopped. A fire boat spraying water at what’s called the dolphin pilings.

That’s what caught fire. The wood bumpers in place to protect the bridge supports from boats.

Contractors with blow torches were working on the pilings. It was just routine maintenance when wood caught fire.

The pilings that caught fire are all over the river. In fact, pilings caused the Great Chicago Flood 27 years ago at Kinzie Street.

Back then, CBS 2’s Pam Zekman broke the story of how the flood started. Turns out, when the city put in wood pilings, one of them caused a crack in the ceiling of a utility tunnel. That caused sub-basements of buildings to flood across downtown.

No one was hurt and there was no damage to the bridge.