Now that state legislators have closed the largest budget deficit in Connecticut history, Gov. Dannel P. Malloy's administration has a new challenge: Fix a state employee pension system on a collision course with fiscal collapse in about two decades.

Office of Policy and Management Secretary Benjamin Barnes, Malloy's budget chief, presented the challenge Tuesday to the legislature's Appropriations and Finance, Revenue and Bonding committees during OPM's annual budget briefing. And though he didn't propose a specific timetable to meet the challenge, it could ultimately add hundreds of millions of dollars in costs to the annual state budget.

"There is enormous work left to be done with respect to the fiscal condition of the state of Connecticut," Barnes told lawmakers as part of his office's Fiscal Accountability Report, an annual briefing on short- and long-term budget issues.

"State government is leaner and more efficient" as a result of the $1.6 billion concessions deal ratified in August with state employee unions, as well as other spending cuts, agency mergers and efficiencies ordered in the $20.14 billion budget adopted in June, Barnes said.

But he also noted that the governor, who took office in January, inherited a financial picture plagued with more than $71 billion in long-term debt -- one of the highest burdens, per capita, of any state in the nation.

That includes: bonded debt stemming largely from school construction, roads, bridges and other capital projects; pension funds and health care benefits for retired state workers and teachers.

Among the pension funds, the program for state employees is in the worst shape.