Venice's Grand Canal turned an alarming shade of fluorescent green over the weekend, drawing crowds of onlookers and prompting a swift environmental investigation. By Sunday afternoon, local authorities had identified the cause: fluorescein, a non-toxic chemical commonly used in water infrastructure studies and eye exams, according to a statement from the regional environmental agency.
The discoloration first appeared near the Rialto Bridge early Sunday morning, when residents and early tourists noticed the water had taken on a vivid, neon hue. Firefighters, police, and environmental officials were dispatched to the site to collect samples, with initial concerns ranging from an accidental spill to deliberate sabotage. Officials told CNN that before test results came back, they had not ruled out the possibility of eco-terrorism, and they remain open to the idea that the incident could be linked to activism.
As the day progressed, the green patch expanded its reach, creating surreal scenes along the famed waterway. Gondoliers navigated through the emerald-colored water while tourists snapped photos from bridges and sidewalks. The sight reminded some of absinthe, the anise-flavored spirit known for its green tint.
Investigators later confirmed that the color was caused by fluorescein, a compound that fluoresces green under light and is widely used in tracing studies to detect leaks in water systems or to test the integrity of infrastructure. The regional environmental agency reassured the public that ecotoxicological analyses showed no toxicity in the samples taken, easing fears of contamination.
Despite the confirmation, questions remain. Officials said it is not clear how the chemical entered the canal, and they have not ruled out the possibility that it was placed there deliberately. Police are investigating whether environmental activists might be responsible, and further test results are expected in the coming days.
A History of Green Water in Venice
This is not the first time Venice's waters have turned green. In 1968, Argentine artist Nicolás García Uriburu dyed the waters of the Grand Canal with fluorescein during the 34th Venice Biennale. That act was intended to draw attention to the relationship between nature and civilization and to promote ecological consciousness as a critical part of culture. While the current incident appears to have no artistic intent, it echoes that earlier moment in the city's history.
For now, Venetians and visitors alike are left with a striking memory and a lingering question: how did a chemical used to trace water flows end up in one of the world's most famous canals? The investigation continues.