The tradition of dyeing the river green arose by accident when some plumbers used fluorescein dye to trace sources of illegal pollution discharges. The parade committee has since switched to a mix of forty pounds of powdered vegetable dye.
The dyeing of the river is still sponsored by the local plumbers union. The dye takes days to dissipate.
|Here you can see where the dye was first added to the river|
|Speed boats run up and down the river to mix the dye|