SPRINGFIELD — Six months after the state’s high court ruled a Chicago pension overhaul unconstitutional, lawmakers are meeting again to come up with a new plan.

A panel of House lawmakers convened this week to discuss a proposal that would change how Chicago funds its largest pension system in order to prevent insolvency.

The key problem, members of the House Personnel and Pensions Committee were told on Monday, is that Chicago is still only required to pay a number that has little relation to how much is needed.

Instead of a number based on the health of the fund and payments required to be made in a given year, the city simply pays a static multiple of how much employees themselves contribute.

For instance, employees might be required to pay 8 or 8.5 percent of their salaries toward pensions. The city would be required to pay an amount that’s 1.25 times that total. For 2016, the required employer payment to the Municipal Employees’ Annuity and Benefit Fund of Chicago is $161 million.

But the number deemed necessary for this year by actuaries is actually about $970 million.

Jim Mohler, executive director of the fund, said the system has about $18 billion in unfunded liabilities as of last year and has only about 20 percent of the funds it really needs. That’s the lowest rate of any employee fund in Illinois, and the lowest of any large municipality in the country, he said.

“The municipal fund must be put on an actuarially defined contribution (plan), and soon, to be able to prevent the unprecedented event of a public pension fund becoming insolvent,” Mohler said at the hearing on Monday, according to a stream of the event by BlueRoomStream.com.

The funding issue was addressed in the law that was ruled unconstitutional by the Illinois Supreme Court earlier this year. In fact, city lawyers used it as a selling point to the justices, arguing that while the law required employees to pay more and earn less, it also created fiscal discipline that would go further in guaranteeing there was money in the bank to pay them when they retired.

But in a decision authored by Justice Mary Jane Theis, the court said that was just reiterating a promise that was already made in Article 13, Section 5 of the state constitution, which says pensions are contracts that “shall not be diminished or impaired.”

“[T]he ‘guaranty’ that the benefits due will be paid is merely an offer to do something already constitutionally mandated by the pension protection clause,” Theis wrote in that decision.

House Bill 705, however, tries to revive the funding structure in the law that was struck down. Beginning this fiscal year, it would require the city to make ramped up payments aimed at bringing the system to 90 percent funding over the next 40 years.

It also allows the board of the retirement fund to bring a mandamus action in circuit court in case the city fails to make a required payment.

The state’s five pension systems for state workers, teachers, judges and lawmakers began those types of actuarially defined payments more than 20 years ago, and the ramping-up of pension payments each year is part of the reason the state’s budget situation is so tricky. The required pension contributions take up more and more funds that may normally go toward other types of spending.

Rep. Jeanne Ives, a Wheaton Republican, expressed concern over what could be a similar type of squeeze for the city, noting the required contribution in 2021 is estimated at around $500 million.

“I believe the entire revenue stream for the city of Chicago is just over $7 billion. Is that about right? So one-fourteenth is going to go to one municipal fund to shore it up? I just don’t know how that works in the end,” she said. “I don’t know how you get that money from anywhere else, for one fund, given all the other problems that Chicago has financially.”

City officials, however, said a recently approved, 30 percent tax on water and sewer usage would help put all four of the city’s pension funds — including the municipal employees’ fund — on the path to solvency. They also said a forthcoming city proposal to ramp up pension payments will also provide the stability the fund needs.

“We believe the water-sewer tax and our forthcoming ramp to (actuarially required contributions) provides the necessary balance between funding the municipal pension fund without placing significant financial strains on the city or our residents,” Carole Brown, the city’s chief financial officer, told the House panel.

The hearing was for informational purposes only. As a result, no votes were taken on any proposals.