Greening a River (and the White House) for St. Patrick's Day

Watching the river turn green has been a Chicago ritual for nearly 50 years. This year was a drizzly grey day, but that did not deter crowds of crazy celebrants wearing tall green-striped hats and lots of green beads from coming downtown to cheer from the Michigan Avenue bridge as 40 pounds of green dye were dumped into the Chicago River just before the parade. Chicago gets a jump-start on other cities by holding its annual ritual on the Saturday before March 17, rain or shine. 

The next best thing to being there may be a fun 60 second, stop-motion video by a British professional photographer who captured the event from the landmark Wrigley Building. I watched from the nearby Trump Hotel tower as the bright neon green color quickly flowed downstream and was reminded that Chicagoans have always done things differently.

Unlike most rivers, the 156-mile Chicago River flows backwards, away from the mouth of Lake Michigan into which it originally emptied. A late 19^th century civil engineering project redirected the flow due west, then south toward the Mississippi basin and eventually to the Gulf of Mexico. It was done for sanitation reasons, to help control sewage and industrial pollution that had led locals to dub it "the stinking river." (It's hard to imagine getting a project like that through today's local, state and national regulatory hoops; in fact the river's flow later came under legal scrutiny up to the U.S. Supreme Court and is regulated by a joint U.S.-Canadian commission).

Similarly, I wondered how the green dye poured into the Chicago River passed environmental muster.  Turns out that things have changed on that score too. Originally 100 pounds of fluorescent dye were used to turn the river green for a whole week; now it's down to 40 pounds of vegetable dye, and the color lasts for several hours.

The original idea came from plumbers who used the fluorescent dye to check for illegal sewage discharges. In 1962, the dye was used to turn the river green in honor of St. Patrick's Day, and a flamboyant local organizer named Steve Bailey once announced that he was changing the Chicago River into the Shannon River for a day.

A few years in, environmentalists attacked the use of the original dye because of potential  hazards to wildlife in the river. Today vegetable dye is used, a supposedly secret formula that is claimed to be safe for the river's living organisms (presumably including the kayakers and other human denizens watching the spectacle from the river perspective who could tumble overboard).

Other cities have followed suit in their own way: the waters in London's Trafalgar Square fountain and Savannah's downtown fountains have been dyed green, and last year First Lady Michelle Obama, a Chicago native, got the water in the White House fountains dyed green. But Chicago's giant green river feat still stands head and shoulders above the rest.

So, while New York rings in the New Year with the drop of its glittery Waterford Crystal geodesic ball in Times Square, come dressed in green to Chicago for your St. Patrick's Day cheer.