The dye originally is orange, but upon interaction with the water, it turns into beautiful, bright kelly green.
And the South Side Irish Parade may be gone, but the southwest suburb of Oak Forest is trying to establish a new tradition this year.
Saturday was the first annual Oak Forest "Fleadh." The fleadh, which is a Gaelic term meaning "festival," was held on Cicero Avenue.
There was a family parade, complete with Irish dancers, face-painting and plenty of green on an otherwise gray day.
"We're pretty excited. They don't have the other big parade now. So, we're coming to the one here now. Kids are excited, looking to have a good time here," said Denis McGinty, an Oak Forest resident.
"It's great for the kids. They enjoy seeing their friends. It's a great way to support the community," said resident Laurie Kirby.
"This is fabulous. I think today is the best day of my life," Oak Forest Mayor Hank Kuspa said.
The fleadh coincided with Oak Forest's second annual Pub and Restaurant Open House.
In another part of town, music filled Old St. Pat's Church on West Adams Saturday morning for a civic celebration of St. Patrick's Day.
Cardinal George took part in the liturgy that featured Celtic music performed by traditional Irish musicians. Mayor Daley and many other dignitaries were there.
A breakfast brunch followed the 9 a.m. mass.
Finally, downtown, a big crowd turned out for a party at the Chicago Hilton on Michigan Avenue.
Families enjoyed dancing, music and food. Balloon artists and face painters also were on hand for the children.
The event raised money to help the children living at the Mercy home for boys and girls.
ABC7 Chicago was a sponsor for the event.