(CNN) If you peered into the Chicago River on Thursday, you might have thought it had rained rubber duckies, but it was actually Chicago's 14th annual Ducky Derby.

Rubber ducks are dropped into the Chicago River to start the annual Ducky Derby.

Exactly 63,133 rubber ducks were dumped into the river at the Wabash Bridge to raise money for the Illinois Special Olympics, according to the organization. Last year, the derby raised over $425,000 for the charity.

Competitors buy ducks, paying $5 for one or up to $1,000 for 240.

The iconic bath toys race down the Chicago River to win prizes for their owners, depending on how they place. This year, the winners got a 2019 Chevy Equinox, $2,500, an all-inclusive vacation to the Riviera Maya, a Chicago weekend getaway or NASCAR tickets.

The ducks are corralled along the river.

Spectators watch from above and cheer on their ducks as they make their way to the finish line.

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