SENIOR TRANSPORTATION OFFICIALS on Tuesday cautioned that major expansion projects prioritized by the Patrick administration could be in jeopardy if tolls on the western portion of the Massachusetts Turnpike come down in four years, but one House lawmaker called the warning “scare tactics.”

Rep. Antonio Cabral, a New Bedford Democrat and chair of the House Bonding Committee, accused the Patrick administration of misleading the public by suggesting that tolls on the western turnpike from Rte. 128 to the New York border will come down in 2017 when the remaining $70 million in bonds are paid off.

The toll issue was cited by Gov. Deval Patrick last week as the rationale for vetoing a $500 million tax bill that will ultimately dedicate $805 million in new spending to finance transportation investments over the next five years. Patrick says the $135 million in lost toll revenue will undercut the financing plan, and limit the ability to borrow for long-term projects. The House and Senate have votes scheduled for Wednesday to override Patrick’s veto.

“I believe the $805 million will be there in 2017 because I don’t see how those tolls are going to come down,” Cabral said during an oversight hearing Tuesday. “To use the scare tactic, if you will, that if we don’t have the $135 million we won’t be able to fund South Coast or the Green Line, is a little disingenuous.”

Cabral referenced a 1952 law that stipulated tolls on the western turnpike will come down when the bonds are paid off and if the highway is in a state of good repair.

“It’s unlikely a responsible secretary of transportation will make the decision to bring those down, so I think we’re focusing too much on this hypothetical possibility,” Cabral said.

Later in the hearing, Cabral tried to get MassDOT Chief Financial Officer Dana Levenson to estimate the cost of getting the Mass. Turnpike into a state of good repair in 2017, describing that cost as the “magic number.”

Levenson declined to provide an estimate, saying it was “not easy” to speculate. He described the toll road as “in reasonably good condition” currently but said road use causes deterioration over time.

“I’d like to come back to you with that specific number,” Levenson said.

But Cabral did not relent. Noting the MBTA’s backlog of state of good repair projects is estimated at between $4 billion and $6 billion, Cabral said he would speculate that the turnpike’s costs are more than zero, to which Levenson responded: “Absolutely.”

Levenson then explained that state transportation officials in April 2012 embarked on a $900 million capital maintenance program for the Metropolitan Highway System, the term used to describe the turnpike as it heads east from Route 128 into Boston and the network of Big Dig tunnels and bridges. State-of-good-repair costs for the state’s overall highway system, which include the turnpike, are in the “billions of dollars,” Levenson said.

“It’s becoming clearer and clear to me that it’s unrealistic they will come down in 2017,” Cabral responded.

Only three lawmakers on the 11-member House committee showed up for the oversight hearing, including Rep. Carl Sciortino, of Medford, and Rep. Paul Heroux, of Attleboro.

Cabral apologized for being 10-minutes late, citing traffic on Route 24 and the lack of other commuting options. “Maybe the lack of commuter rail to New Bedford,” Cabral said, suggesting he might have an easier commute if South Coast rail becomes a reality.

Levenson said that once a transportation financing plan is in place, MassDOT will take a comprehensive look at the list of priority projects and make determinations on which will go forward and what needs to be “tabled” based on the finances available.

Those projects include major expansions like South Coast rail, the Green Line extension, and the expansion of South Station, as well as maintenance projects and purchases such as the purchase of new Orange and Red Line cars and 480 new buses.

MBTA Chief Financial Officer Jonathan Davis said he believed the financing plan passed by the Legislature would be sufficient to balance the MBTA’s budget for the next five years and purchase new Red and Orange Line cars, which he described as “critical” given that cars currently in service are 35 to 45 years old.

Davis said the T was “hopefully” done with larger fare increases but reminded lawmakers that the state’s plans, even with the infusion of new revenue from tax hikes, call for more regular fare increases.

“It’s 5 percent in 2015 and it’s 5 percent in 2017,” Davis said.