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CHICAGO — Heavy rains caused widespread flooding across the Chicago area, including the basement of the Willis Tower and Lower Wacker Drive.

ComEd crews were downtown Monday, working underground to address power outages created by flooding over the weekend.

Efforts remain underway to restore electrical service to Willis Tower. The outage is caused by flooding from the Chicago River along Lower Wacker Drive, that knocked out a ComEd substation.

Efforts by the city have stopped the waters from rising in Lower Wacker. The city has begun a pumping process to lower the water levels so ComEd crews can get into the substation under the Willis Tower.

The high-rise was evacuated of everyone who needed to be out.

It is unknown exactly when power will be restored to the building.

The Willis Tower is the only building that was impacted as a result of the downtown flooding.

Lower Wacker is closed after it was flooded with several feet of water, causing police to block the entrances to the underground roadway.

This is a developing story. Check back for details.

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