People gather at the edges to see dye turn the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

Jerry Steadman, of Chicago, looks on as dye turns the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

Zach Cosme (from left), 5; Jacob Aardsma, 5; and A.J. Bale, 5, show off their green mustaches as they watch dye turn the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

Daniel Loftus, 5, and his baby sitter Karen Robinson, of Worth, who is holding an Irish flag Daniel made in school, look on as dye turns the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

Jacob Aardsma, 5, of Palos Heights, reacts as dye turns the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

People look on as the color green begins to gurgle from the top of Lake Katherine's waterfall in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

A.J. Bale, 5, of Palos Heights, mugs for his mother's camera as dye turns the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

A.J. Bale, 5, of Palos Heights, mugs for his mother's camera as dye turns the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

The color green begins to spill over the top of Lake Katherine's waterfall in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

Children play at the edges as the color green begins to spill over the Lake Katherine's waterfall in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media

Noah Insalaco, 3, of Crestwood, closely examines the color of the water on a stick as dye turns the Lake Katherine waterfall green in Palos Heights, Illinois, Friday, March 15, 2013. | Joseph P. Meier~Sun-Times Media