The duck is just one of the attractions at the five-day Festival of Tall Ships.
At 2 p.m., the six-story-tall duck sculpture will lead a parade of domestic and international ships making their way along the Main Channel.
Event organizers say the rubber duck is an impressive sight to see.
"This is 61 feet, 11 tons, about 85 feet wide and about 110 feet long," said Craig Samborski, spokesperson for the Festival of Tall Ships. "I was shocked when I saw the size of it right in front of me."
PHOTOS: Giant rubber duck wows spectators
The event, which runs until Sunday, will also feature ship tours, cannon battles, sword fights, knot-tying and sail-rigging training demonstrations, live music and food trucks. Tickets range from $7 to $350. For more information, visit http://www.tallshipsfestivalla.com.
City News Service contributed to this report.