history of dyeing the chicago river green

Chicago’s Green River: St. Patrick’s Day History & Boating Guide

Written by Boatsetter Team
March 14, 2024

Last Updated on March 14, 2024 by Boatsetter Team

St. Patrick’s Day celebrations, held every year on March 17, are naturally associated with good old-fashioned fun. Green-wearing celebrants march in lively downtown parades in large cities and small towns across the United States. Each year over 100 St. Patrick’s Day parades take place all across the country, and even in other parts of the world.

Celebrating St. Patrick’s Day in Chicago, Illinois, for instance, brings to life one infamous tradition that always turn heads—and is of special interest to boaters. The world-renowned Chicago Green River.

Find Available Boat Rentals in Chicago

History of the Chicago Green River

Believe it or not, a good stretch of the Chicago River is dyed bright green on the Saturday before this iconic holiday. The river-dyeing event always takes place on the same date as Chicago’s St. Patrick’s Day Parade.

Not surprisingly, the Green River event has a long and colorful history (pun intended). In fact, in 2024 Chicago will mark the 62nd anniversary of this landmark occasion. Here’s how it all began…

Why is the Chicago River dyed green on St. Patrick’s Day?

In 1961, Chicago’s Mayor Richard J. Daley wanted to spruce up the city’s riverfront section; however, the river was full of sewage, and it looked and smelled horrible. To determine the sewage’s source, and identify the responsible parties, Mayor Daley ordered public works officials to pour a bright green dye into the river.

Naturally, the job fell to the Chicago Journeymen Plumbers Local Union 130. It was easy to tell which members got the enviable job, as their coveralls were covered in green dye after the day’s work.

The Very First Green River Event

It didn’t take long before news spread throughout the city of this occurrence, and soon, St. Patrick’s Day Parade chairman (and Plumbers Local member) Stephen Bailey got a flash of inspiration. Why not use the same technique to give a good-sized stretch of the Chicago River a greenish tint for St. Patrick’s Day? As Mayor Daley’s good friend, Bailey easily got the approval to turn the Chicago River green.

Three months later, Plumbers Local workers poured 100 pounds of green dye into the river just before St. Patrick’s Day. The dye worked remarkably well, turning the river a bright green that lasted for a whole week.

Understandably surprised at the substance’s lasting effects, workers cut the dye back to 50 pounds over the next two years. Over the following decades, the Plumbers Local workers tweaked the dye amount again and again. Finally, workers determined that 50 pounds of dye would turn a quarter-mile of the Chicago River green for up to two days.

How does Chicago celebrate the Green River?

chicago river green

Chicago’s Green River plays a key role in the city’s St. Patrick’s Day celebrations. For starters, the river-dyeing event is always held on the same morning as the St. Patrick’s Day Parade. In 2024, the event will take place on Saturday, March 16 at 10 a.m. An entire city block, or the stretch between Columbus Drive and State Street, will be the lucky recipient.

Over 400,000 hardy revelers have two options for getting up close and personal with the Green River. First, the green-tinged section will extend for a whole city block, covering Columbus Drive to the State Street portion of the river. This means people traveling over any of four bridges can glimpse this decidedly unusual winter phenomenon.

Great land-based vantage points

For an ideal (and free) vantage point, head over to the Chicago Riverwalk. Arrive early, and stake out a spot between State Street and Columbus Drive, overlooking the scene of the river-dyeing event. In fact, the Michigan Avenue Bridge is, hands down, one of the best places to watch the process unfold.

Don’t mind shelling out a few bucks? If so, purchase a ticket to a strategically located rooftop viewing event. As a bonus, you’ll be treated to a wide-ranging view of the Chicago skyline. Dress in layers to avoid hypothermia, and get ready to enjoy a show you’ll remember for years.

Chicago River on-water viewing spots

Of course, viewing the St. Patrick’s Day Green River spectacle from the water can’t be beaten. You can easily book a boat rental of your choice using Boatsetter to fit all your St. Patrick’s Day party-planning needs. Browse boats of all different sizes and styles, and even opt to have a USCG-certified captain do the operating—that way you don’t need to worry about a thing.

If you really want to get festive, connect to the onboard Bluetooth speakers onboard to blast authentic Irish bagpipe music.

Pack Irish food and libations to enjoy, and when events wrap up, your local captain will navigate you and crew to the best viewing spots for the Chicago St. Patrick’s Day Parade.

Book Your St. Patrick’s Day Boat Rental Now

How is the Chicago River dyed green?

Dyeing the Chicago River green is a two-step process that takes just under an hour. A Plumbers Union crew hops in one or two large powerboats early in the morning. A smaller boat tags along behind.

First, the large powerboats’ crews disperse the dye into the water with flour sifters. Next, the smaller boat spins back and forth to churn the dye and water together. After about 45 minutes, the dye takes effect, and the Chicago River turns a bright green color.

How long does the Chicago River stay green?

Once the dyeing process is finished, the river will keep its green tint for 24 to 48 hours. Of course, this duration assumes that 50 pounds of dye are used for the same quantity of water. If the ratios go up or down, the dye could last longer or shorter intervals.

Is dyeing the Chicago River green safe?

In the early 1960s, the Plumbers Union used oil-based fluorescein to dye the Chicago River green. Environmentalists strongly objected to this move, saying the dye made the river’s condition even worse.

In 1966, the St. Patrick’s Day Parade organizers agreed to stop using the toxic oil-based dye. Instead, they switched to using 25 pounds of a vegetable-based powdered coloring agent. Interestingly, the dye powder is orange until it mixes into the water.

Finally, the Plumbers Union says the new bright green dye is environmentally friendly. However, they still won’t divulge its makeup, as the green dye recipe is a closely guarded secret.

Chicago River and Lake Michigan Boating Tips

Chicago’s notoriously harsh winters drive most recreational boat owners off the water until spring. However, during the boating season, the Chicago River and Lake Michigan offer some great boating and fishing opportunities.

With plenty of room for everybody, these waters are home to numerous runabouts, convertibles, motor yachts, and sailboats. Many smaller vessels opt for day trips, dropping the hook for lunch or checking out some favorite fishing spots. Boaters on well-equipped larger vessels often enjoy a weekend or even weeklong cruises.

Boaters who are itching to get on the water, and don’t have their own boats, can take advantage of an easy-to-book boat rental with Boatsetter. Choosing the right boat takes just a few clicks, and it opens the door to some relaxing fun on the water.

Browse All Available Boat Rentals in Chicago, IL

Browse by experience

Explore articles