Chicago River dyed green for St. Patrick’s Day

The Chicago River has been dyed a bright shade of green, kicking off the city’s St. Patrick’s Day festivities.

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

WATCH: 2015 timelapse video of dyeing Chicago River green

A parade was also scheduled. Mayor Rahm Emanuel, Republican Gov. Bruce Rauner and many candidates running in Tuesday’s primary election were expected to march.

READ MORE: Increased police patrols in Waterloo as thousands expected for St. Patrick’s Day

The grand marshal is 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.