50 years after people, Due to the Wells Fargo Center's curved roof falling ice and snow was always a danger. To remedy this a heating system was installed on the building's roof to prevent snow from accumulating on it. But now the roof is covered with snow every winter and downtown Denver is witness to periodic avalanches as snow slides off the building's roof.
200 years after people, The Wells Fargo Center has begun to collapse as it's roof has accumulated snow and ice over each winter without people. The building's steel skeleton finally succumbs and the Mile High City's 3rd tallest building collapses.