The Friends of the Chicago River group say they’re not thrilled about the city’s decision to dye the river blue to celebrate the Cubs World Series.

The city says the coloring is an eco-friendly vegetable dye, but Friends of the Chicago River spokesperson Margaret Frisbie said the exact ingredients aren’t disclosed.

“We have a legacy of treating the river as an object in Chicago as opposed to an actual resource. And dying the river blue to celebrate just continues the frame of mind that this is something to be manipulated, not something to be celebrated and taken care of,” she said.

The Illinois Environmental Protection Agency requires a permit for dumping things in bodies of water, but the agency did not require the city to get a permit to dye the river for St. Patrick’s Day or for the Cub’s celebration.