An underground fire has plunged blocks of downtown Calgary into darkness and the power authority, Emmax, says it doubts power will be restored in less than four days. Residents and businesses will remain without power in the critical urban hub following damage to wires and cables. Enmax has shut down power to a large swath of downtown, from 4th Avenue to 7th Avenue S.W. and 4th Street to 11th Street S.W., as crews repair the damage. It will take a minimum of four days to repair the damage and get power back online, Enmax reported.