Crews pump floodwater from Willis Tower but power still out, officials say

CHICAGO (WLS) -- The tallest building in Chicago is still without power Thursday as crews work to assess the damage from after a substation in Willis Tower flooded due to heavy rain earlier this week.

ComEd said as of Wednesday night crews were able to pump out all four-feet of water that flooded the tower's basement and repairs have begun.

Officials said there is no estimate yet on when power will be restored.

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ComEd is working with building management, CFD and the city of Chicago to re-energize the Willis Tower safely, officials said.

Crews will have to restore power to the high-rise in phases, a ComEd spokesperson said.