BOK Tower was built for the Williams Companies, whose CEO at the time, John Williams, was impressed by the Twin Towers and originally wanted to build two 25-story replicas in Tulsa.The similarities to the World Trade Center led executives to joke that the architects just halved the plans for a World Trade Center tower.[5] BOK Tower, as completed, was the tallest building in Oklahoma and contained 1,100,000 square feet (100,000 m2) of office space.[7] In December 2005, a water main broke and flooded electrical equipment in the basement.$6 million was spent on renovated pedestrian bridges, granite coating for the base, new fitness centers, and windows.