Post-secondary students in Edmonton have been using public transit so much that they are likely to pay more, possibly double, in the future for their passes.

The passes aren't an option for students, and they have taken advantage of them, taking the bus far more often than first anticipated. A new city report says student ridership on Edmonton Transit increased by 32 per cent in the period from 2006 to 2008.

The three-year pilot project for the U-Pass for students at Grant MacEwan University and the University of Alberta was introduced in 2007. Each pass, which allows students to ride transit in Edmonton, Strathcona County and St. Albert, costs $97 a term, of which the students pay $81 and the universities pay the rest.

The report says the increased ridership among students cost the city $6.6 million in 2008.

In order to break even, the report recommends a cost increase that would be phased in over several years, with the price ending up at $155 a term in the 2013-2014 school year.

After that, city staff recommends the U-Pass price be set according to a formula based on 30 per cent of the adult cash fare of 40 trips per month, which would put the U-Pass price at $171.42 per term in 2014-2015.

Coun. Don Iveson said he hopes students understand why the cost needs to go up.

"When their demand has been so much greater than we thought, we do need more funds in order to meet their demands for transit service," he said.

The U-Pass program is in the final year of its three-year pilot. Students will hold referendums next spring on whether to continue the mandatory program in the 2010-2011 school year.

The price increase is unfortunate, but it was important to ensure the program was sustainable, said Nick Dehod from the University of Alberta Student Union.

"We feel that what's been put forward in the proposal is something that will still provide a benefit to students," he said.

Edmonton city council will discuss the recommendations Tuesday at its transportation and public works meeting.