Chicago aldermen are scheduled to meet Monday for a marathon session on the city’s underfunded pension system.

The special meeting is scheduled to last six hours, and it’s prompted fiscal watchdog groups like The Civic Federation to pay attention.

Laurence Msall heads the group.

“It is likely that even with the significant reforms that Mayor (Rahm) Emanuel has called for, that Governor (Pat) Quinn has called for, that even with those reforms, everyone is going to have to contribute more, ” said Laurence Msall, who heads The Civic Federation. “The City of Chicago taxpayers will have to pay more taxes, the city of Chicago residents will likely receive less services and the pensioners and the city employees will have to receive less of a benefit if we’re going to stabilize this government.”

Msall said that in fiscal year 2010, Chicago had $14.7 billion of unfunded obligations to police, fire and some other employees. He said Mayor Rahm Emanuel has floated some reasonable ideas, like increasing the retirement age and putting a temporary freeze on cost of living adjustments for retirees.

But Msall said the state legislature must first change the mandatory pension obligations for city governments across the state.

Meantime, Chicago aldermen weren’t overly enthusiastic about the prospects of a day-long meeting to discuss the city’s pension obligations.

“We have a big hole to get out of and Monday is an opportunity to find out how deep that hole is,” said Alderman Pat Dowell. “I will be there as long as I can be there, but a six hour hearing is pretty daunting.”

And Alderman Bob Fioretti said there’s a lot of blame to go around for the city’s underfunded pensions.

“We have to protect the rights of those that have invested in it. They have constitutional rights that - of their vesting, and at the same time we need to find ways to change the future,” he said.

WBEZ’s Quinn Ford contributed to this report.