CHICAGO, IL – MARCH 17: Boats navigate the Chicago River shortly after it was dyed green in celebration of St. Patrick’s Day on March 17, 2018 in Chicago, Illinois. (Photo by Scott Olson/Getty Images)

CHICAGO (AP) — The Chicago River was dyed a bright shade of green, kicking off the city’s St. Patrick’s Day festivities.

READ MORE: 15-Year-Old Critically Injured In Shooting At Timberview High Released From The Hospital

Thousands of people lined the riverfront downtown Chicago on Saturday to see the dyeing, a tradition for the holiday that dates to 1962.

A parade was also held. Among those marching in the parade were Mayor Rahm Emanuel, Republican Gov. Bruce Rauner and many candidates running in Tuesday’s primary election.

READ MORE: More Than A Dozen Texas Congressmen Complain About Mexico Energy Changes

The grand marshal was Alderman Patrick O’Connor. He says it’s a chance to celebrate “the hard working Irish men and women” of Chicago.

The Chicago Plumbers Union started the tradition of dyeing the river green, with a material once used to locate leaks in buildings. Organizers say the powder used is a secret recipe and is environmentally safe.

MORE NEWS: Shooting And Flipped Vehicle Results In Section Of LBJ Freeway In Balch Springs Shut Down For Hours

(© Copyright 2018 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)