It’s a Chicago tradition in its sixth decade — the Chicago River is dyed green the Saturday before each St. Patrick’s Day (unless the holiday falls on a Saturday).
The dyeing process starts at 10 a.m. Saturday, March 16, and stretches from Orleans Street almost three quarters of a mile east to Columbus Drive.
How the tradition began
The first person entrusted with turning the river green was William J. Barry, a Chicago port employee who died in 1985. Mike Butler assumed the role in the early 1970s.
“Bill was from Bridgeport,” Butler told the Tribune in 1995. “The mayor trusted him. Bill’d do anything for the mayor. Even though he was a little afraid of water, he went out there. That’s how much he loved the mayor.”
Butler led the volunteer crew for more than 40 years. He died in 2016, but the annual dyeing of the Chicago River for St. Patrick’s Day is still a family reunion for the Butler and Rowan clans, the two families responsible for the tradition of turning the murky water into a bright “Ghostbusters” Slimer green.
How the Chicago River is dyed green
According to Tom Rowan, head of the crew
Prep work: Early in the morning, the crew arrives at a city boat slip on the North Branch of the river. Everyone wears clothes and shoes they don’t mind getting dirty and a white paper smock over their clothes.
On the water: The crew hops aboard two small motorboats donated by volunteers. The larger boat, at approximately 18 feet, has a crew of four. The smaller boat, a 12-footer, has two people.
A 10 a.m. start: The larger boat is responsible for dyeing the river, which begins when it arrives under the Michigan Avenue bridge near Wacker Drive.
Kitchen secret: Three men use flour sifters to dump about 40 pounds of an environmentally friendly orange powder into the river. The fourth drives the boat. The formula for the powder, which turns the water bright green when it hits, is top-secret.
Powder spread: The smaller boat “chases” the larger boat and churns up the water, which helps disperse the powder across the river. Traveling the river between Wabash Avenue and Columbus Drive, the large boat snakes across the waterway dumping powder.
Green sheen: It takes about 45 minutes for the river to turn completely green. Depending on which direction the wind is blowing, the water can stay green for up to a few days.
That one time the river was dyed blue
A crew dyed the Chicago River blue in 2016 to celebrate the World Series champion Cubs on the day of the team’s victory parade and celebration.
Sources: As told to the Chicago Tribune by Tom Rowan and Michael Butler, whose families have been involved in dyeing the Chicago River since 1962; illustrations by Rick Tuma; Chicago St. Patrick’s Day Parade Committee; Choose Chicago; Tribune reporting and archives
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