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Members of the Chicago Journeymen Plumbers Local Union 130 pour green dye into the Chicago River as part of the annual St. Patrick's Day festivities Saturday, March 14, 2015 as seen from the terrace of the Trump Tower in Chicago.
Anthony Souffle
Members of the Chicago Journeymen Plumbers Local Union 130 pour green dye into the Chicago River as part of the annual St. Patrick’s Day festivities Saturday, March 14, 2015 as seen from the terrace of the Trump Tower in Chicago.
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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

Mayor Richard J. Daley is credited not only with reviving Chicago’s St. Patrick’s Day parade, but also proposing the idea of greening part of Lake Michigan to celebrate the holiday. It was his boyhood friend and Chicago Plumbers Union business manager Stephen M. Bailey who suggested dyeing the Chicago River instead. The Chicago River would run green for the first time in 1962 (the same year the photo below was taken), one year after Savannah, Ga., unsuccessfully tried to dye its river green for the Irish holiday.

The first year of river-dyeing, the boat crew used an oil-based Air Force dye that kept the river green for nearly a month and caused an outcry from environmentalists. So a vegetable dye was substituted.

City workers use vegetable dye to turn the Chicago River green for St. Patrick's Day in 1976.
City workers use vegetable dye to turn the Chicago River green for St. Patrick’s Day in 1976.

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.”

Mike Butler, who was in charge of dying the Chicago River green for St. Patrick's Day for more than 40 years, died July 12, 2016. He was 81.
Mike Butler, who was in charge of dying the Chicago River green for St. Patrick’s Day for more than 40 years, died July 12, 2016. He was 81.

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

The Chicago River is dyed blue near the Michigan Avenue bridge in honor of the Chicago Cubs World Series win.
Erin Hooley / Chicago Tribune
The Chicago River is dyed blue near the Michigan Avenue bridge in honor of the Chicago Cubs World Series win.

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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