David Suzuki had some pretty harsh words about Calgary, calling the city an ecological disaster.

"The urban sprawl there [Calgary] is crazy, absolutely crazy. It's dependant on the car and it's just not the way that you build community," said Suzuki. "We've got to decide, as communities, are we a community for people or are we a community for cars...we've got to work against the car and make communities where people get out and walk."

Suzuki made the comments at the 2008 Canadian Urban Forest Conference in Sherwood Park on Tuesday.

Several Calgarians, who CTV News spoke to, say the environmental activist has a point.

"I think if we build up, rather than out, we would have a great chance of saving a lot of gas," says David Bryant.

"If we had a better transit system, people wouldn't have to drive. Just going from north to south, most people would have to drive because it's so far," says Angela Wong.

A professor at the University of Calgary says while everyone may not agree with Suzuki, we do need people voicing those concerns. "We do need those voices, we do need to avoid ecologically what we've just seen happen on the financial markets, and we need someone to warn us that that's where we're going if we don't do anything," says Noel Keough from the university's sustainable design department.

But it wasn't all criticism for Calgary. Suzuki said there are some very good things about the city including its use of wind power to run the LRT and helping to fund the largest wind farm in Canada.