The Electrical Water Pageant is a water based electrical parade (similar to the Main Street Electrical Parade) that takes place in the Seven Seas Lagoon and around Bay Lake.
The 14 barges, each with 25ft tall lighted displays, debuted on October 26 1971 as part of the opening celebrations of Disney's Polynesian Village Resort and the Contemporary Resort.
Typical schedule, but subject to changes.
Disney's Polynesian Resort - 9pm
Disney's Grand Floridian Resort - 9:15pm
Disney's Wilderness Lodge - 9:35pm
Disney's Fort Wilderness Resort - 9:45pm
Disney's Contemporary Resort - 10pm
Magic Kingdom - 10:25pm
(When park is open after 10pm)