Any nonconforming building, structure or use, or one or more of a group of nonconforming building, structure or use related to one industry and under one (1) ownership, which has been damaged by fire, flood, explosion, earthquake, war, riot or act of God, may be reconstructed and used as before, if done within twelve (12) months of such calamity. The City Council, after review and recommendation by the Planning and Zoning Hearing Officer, may determine that such delay in reconstruction was caused by unforeseen circumstances beyond the control of the owner of the premises and permit a reasonable extension of time for reconstruction. Any district requirements may be waived by the City Council, provided the area restored is not more nonconforming than existed at the time of the calamity.