CHICAGO — Thousands of revelers lined the streets Saturday to watch the Chicago River be dyed green for St. Patrick's Day.
The annual tradition that dates back decades took place Saturday morning on a stretch of the river in downtown Chicago. Celebrants stood on the Michigan Avenue bridge and the city's riverwalk to watch members of Chicago Plumbers Local 130 dump and spray the dye into the river from boats.
The union says the dye formula is a "closely guarded secret" but members assure that it's been tested and is safe for the environment.
Afterward the city stepped off its annual St. Patrick's Day Parade, one of the biggest parades in the city. Participants in the 64th annual parade included Irish step dancers, bagpipers and marching bands.
Thousands celebrated their Irish heritage — bathed in green, white and orange.
There were new security measures in place this year, including a ban on alcoholic beverages. Organizers said they wanted to tighten security to make sure everyone stays safe.
For more information, go to chicagostpatricksdayparade.org.
The party continues Sunday with the annual South Side Irish Parade.
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