A green space at the University of Toronto was approved for a major transformation last year — turning the field from natural grass to artificial turf. 

Construction was supposed to begin next month, with the new field being ready in time for the 2015 Pan Am and Para Pan Am Games.

Many were angered the university decided to turn the natural grass field into an artificial one.

Now a city councillor is pushing to protect the field as a heritage site.

"It's been a green, open space since before the city existed," said Coun. Adam Vaughan. 

But the university doesn't agree.

"For it to be designated as a heritage landscape, is at best confusing," said Ira Jacobs, a professor at U of T.

The university has wanted to go turf for the last 10 years. It says maintaining the Kentucky blue grass, which is not native to Ontario, is impossible.

"The grass fields ... by the end of September, are a mud pit," said Jacobs.

One of the big pushes behind getting rid of all this grass is the 2015 Pan Am and Para Pan Am Games.

The organization is footing more than 50 per cent of the cost. So if there's no artificial turf the Pan Am organizers will have to find new sites for field hockey and para soccer.

"We're monitoring the situation closely. I can tell you the U of T is a great partner, and we believe they have a tremendous plan to leave what would be a great legacy for not only student athletes, the community and high performance sport," said Pan Am spokesman Teddy Katz.

Construction on the $9.5 million project now hinges on an upcoming city council vote.

"Before we industrialize with asphalt, concrete and plastic, we should take a look at see whether it's worth preserving as part of the legacy of the city," said Vaughan.