Graffiti in the men's washroom had yet to be cleaned up Thursday. (Zulekha Nathoo/CBC)

Contractors are scrubbing down a downtown park after an attempt to give graffiti artists a legal spray-painting zone turned into "a barrage of visual diarrhea," according to a city alderman.

A clean-up crew contracted by the city has removed hundreds of graffiti images this week from the Landmark building at Shaw Millennium Park, which is home to a large skateboard park.

"Without my knowledge, we had an experiment that went horribly wrong, and what we are seeing now is the aftermath," said Ald. John Mar, who represents the area.

On the weekend, the city launched a pilot program allowing young people to paint "urban art murals" on the building with Calgary graffiti artist David Brunning, who goes by the name TheKidBelo. The plan for the pilot project was to have a peer review process decide what is allowed to remain.

'Mayhem ensued'

But Mar, who was on vacation at the time, said it appears "mayhem ensued," and people descended on the park with spray paint, covering every surface with tags, profanity and homophobic and anti-police statements, including urinals in the men's washroom. It will cost thousands of dollars to clean up the park and remove everything, including the sanctioned artwork that was destroyed by graffiti, Mar said.

"I think the difference between graffiti and art is permission," he said. "There was one segment that was supposed to be allowed by the City of Calgary, and what we saw was graffiti on every surface that was available.

"We can't have anti-homosexual slogans. We can't have profanity. What we have done now is taken the park back for the citizens of Calgary and the youth that want to use it in a clean and friendly matter."

Rachel Seupersad, the public art manager with the city, said what happened was unfortunate and lessons have been learned from what was, after all, a pilot project meant to engage youth.

Hank Bruce of Goodbye Graffiti, which was cleaning up the park on Thursday, said oil pastels, chalk and ink markers were also used, making the clean-up difficult.

"The entire Landmark building here was entirely covered," he said. "There are a few fellows out there who are really good artists. They have talent. But that's usually is just one per cent of what I see on a daily basis."