To expand bus service, the Utah Transit Authority is eyeing borrowing money next year through bonding to enlarge or build new garages because current ones are essentially at full capacity.

UTA leaders delivered that message Tuesday to the State Bonding Commission.

Before UTA may borrow more money through bonding, that commission now must approve it because of restructuring ordered last year by the Legislature. That came, in part, over concern about UTA’s $2.1 billion debt, incurred essentially as a mortgage to speed construction of its TRAX and FrontRunner rail systems.

Payment on that debt is now UTA’s single largest expenditure each year, costing $119.6 million this year compared to the $102.1 million that UTA is spending on bus operations.

UTA leaders on Tuesday presented their first-ever report to the bonding commission about their long-term finances, and gave a heads-up that it soon will seek approval for some borrowing.

“We're at the capacity of our current bus facilities,” UTA Board Chairman Carlton Christensen said. ”So if we add service — which we've made a commitment for, and are going through the process to determine that level — we actually need some facilities to house those buses.”

UTA is planning to borrow about $35 million through bonding next year for this purpose — about 1.6% of the amount it already has outstanding in bonds.

It would cover about half the cost of a new maintenance facility planned behind UTA headquarters in downtown Salt Lake City.

UTA officials earlier thought they may need to borrow as much as $57 million, but have been able to reduce the amount by successfully winning federal grants, said Bob Biles, UTA vice president of finance.

Interim UTA Executive Director Steve Meyer said the new facility will replace old garages in downtown Salt Lake City and not only expand capacity but allow the agency to buy and maintain more electric and compressed natural gas buses — in addition to its standard diesel fleet.

After UTA completed its current TRAX and FrontRunner train systems, its officials had said the train system is essentially complete for now and they would shift focus to improving neighborhood bus systems — which critics said had been neglected during the train expansion.

Christensen said UTA is trying to keep that commitment, and currently is studying where to extend hours of operation and where to add or expand routes. He said the agency figures more maintenance facilities will be needed throughout its six-county system to allow that.

The bonding commission also asked how serious proposals are for a $1.2 billion expansion of TRAX to Lehi, mostly to serve new development expected as the current state prison is moved from the Point of the Mountain.

The state’s Point of the Mountain Commission is pushing for that TRAX expansion, saying the state could lose thousands of jobs and key economic development without it. UTA is managing a study funded in part by Draper, Salt Lake County and others to look at the feasibility of such an expansion.

Chistensen said no funding currently is available for that TRAX expansion, and “it’s difficult for us to go forward without a new revenue source.”

Still, he said, “We’d be naive not to plan for that, given the rate of growth” expected to come at the Point of the Mountain and transportation needs there.

As the Bonding Commission explored UTA finances in depth on Tuesday, it also asked if the agency had any plans to raise fares — which last were increased in 2013.

Christensen said UTA is about to start a review of its overall fare structure. He said the cash fares charged are still relatively high compared to other agencies nationally. But once discount passes are figured in, what UTA charges passengers overall is in the middle of the pack.