The Fairfax County Board of Supervisors is trying to figure out a way to save some of its key social services programs, after learning that Virginia officials would not give the county any extra money to help plug a massive budget shortfall.

The board is scheduled to vote Tuesday on how much of the more than $13 million left over from its fiscal 2012 budget to give the Fairfax-Falls Church Community Services Board, which oversees most of the county's service programs for residents with mental illnesses, substance abuse problems and disabilities, as well as the popular Infant & Toddler Connection program.

Earlier this year, the Community Services Board announced a shortfall of nearly $9.5 million for fiscal 2013. The county immediately set aside a portion of funding from its own 2013 budget and sought money from the state.

But Supervisor Penny Gross, D-Mason, said the board recently received a "very disappointing" letter from Gov. Bob McDonnell that "didn't offer anything" to assist with overcoming the funding gap.

As a result, the board will vote to use money from the county and restructure -- and possibly even cut -- certain CSB programs. Still, Chairwoman Sharon Bulova said the county board will continue to work to ensure the CSB's key services are not interrupted.

"This is such an important board to all those living in the county," Gross said. "It fully serves all those in the county who are the hardest to serve ... It does a lot for everyone."

Among the programs that may be hit is the county's Infant & Toddler Connection Program, which provides evaluations and early intervention services for children up to age 3 and sees an average of 1,155 children a month.

Since 2010, the program has seen a 38 percent increase in enrollment. Without additional funding, county board members say a large number of families will end up on a waiting list.

In testimony to the county Human Services Council, CSB Chairman Mark Sites said the board intends "to do everything in our power to ensure that neither we, nor you, find ourselves in this kind of budget and service crisis again."

Despite recognizing the "CSB issue needs to be resolved," Supervisor Pat Herrity, R-Springfield, said he hoped the county would put most of its carry-over into reserve. County Executive Ed Long has predicted county-wide budget shortfalls for both fiscal 2014 and fiscal 2015.

CSB officials said they won't know what to expect from the board meeting until Tuesday and declined further comment.

The county board has scheduled a hearing to discuss the fiscal 2012 carryover for Tuesday morning.