NORWALK - Today marks the 10-year anniversary of the big Northeast blackout that left millions of people powerless.

Many residents say they will never forget where they were the day the lights went out. One woman told News 12 she was getting married on a cruise ship along the Hudson when everything just went black.

The 2003 power outage spread from Ohio to seven other states, including New York and parts of Canada. The outage affected more than 100 power plants. The blackout was blamed in part on trees touching higher-voltage transmission lines.

Officials at ISO New England say they have invested more than $1 billion in upgrades to the transmission system in southwestern Connecticut following the blackout. They say they have also restructured how electrical grids in the Northeast are managed.