The debate about how to fix California’s grumbling roads is heating up after Gov. Jerry Brown, along with leaders in the Senate and Assembly, presented a plan that would raise gas taxes 12 cents per gallon — the largest in state history.

The plan has drawn significant opposition from Republicans, anti-tax groups and others concerned about the state’s growing tax burden.

Assemblyman Vince Fong (R-Bakersfield), who has presented his own bill to finance road improvement and construction, was among the Republicans voicing opposition to the governor’s proposal.

“We already pay one of the largest gas taxes in the country,” Fong said in a Facebook video. “We should not continue that direction. We have a better proposal. I have introduced (Assembly Bill 496) that actually funds our roads and builds new roads without raising taxes or fees. That is a better way.”

Fong said the proposal unfairly targets low and middle-income families. The plan also raises vehicle fees, including a first-time fee for hybrid vehicles.

The Associated Press reported that the state has a $58 billion backlog in deferred maintenance on highways, with anther $78 billion in deferred maintenance to local streets. The proposed tax increase, which also includes raising vehicle registration fees, would raise $52 billion.

“Yes, it costs money. And if the roof in your house is leaking, you better fix it, because it gets worse all the time,” Brown said at a Capitol news conference. “This is mostly about fixing what we already have. If for some reason people try to fight this, and God help us if they were successful, they won’t defeat this, they’ll just delay it and make the expenses go up.”

State legislative leaders could act on the proposal as soon as April 7.

Fong, along with other Republicans, have maintained that the state has neglected road improvements and maintenance by raiding existing transportation taxes to cover general fund expenses.

Fong has been making the rounds with media to attack the plan, including a Wednesday appearance on Los Angeles radio show “John and Ken.”

“We actually generate $7.8 billion using existing money that we already pay for to build roads,” Fong said. “We can do everything that needs to be done.”

Brown outlined how the plan would fund improvement, along with accountability.

The first part of the plan would be called “Fix Local Streets and Transportation Infrastructure” and wound account 50 percent of spending:

• $15 billion in “Fix-It-First” local road repairs, including fixing potholes
• $7.5 billion to improve local public transportation
• $2 billion to support local “self-help” communities that are making their own investments in transportation improvements
• $1 billion to improve infrastructure that promotes walking and bicycling
• $825 million for the State Transportation Improvement Program local contribution
• $250 million in local transportation planning grants.

The second part would be spending 50 percent of the money on highways and freeways:

• $15 billion in “Fix-it-First” highway repairs, including smoother pavement
• $4 billion in bridge and culvert repairs
• $3 billion to improve trade corridors
• $2.5 billion to reduce congestion on major commute corridors
• $1.4 billion in other transportation investments, including $275 million for highway and intercity-transit improvements.

The governor outlined accountability plans to help ensure the projects get built:

• Constitutional amendment to prohibit spending the funds on anything but transportation
• Inspector General to ensure Caltrans and any entities receiving state transportation funds spend taxpayer dollars efficiently, effectively and in compliance with state and federal requirements
• Provision that empowers the California Transportation Commission to hold state and local government accountable for making the transportation improvements they commit to delivering
• Authorization for the California Transportation Commission to review and allocate Caltrans funding and staffing for highway maintenance to ensure those levels are reasonable and responsible
• Authorization for Caltrans to complete earlier mitigation of environmental impacts from construction, a policy that will reduce costs and delays while protecting natural resources.

Guided by the principles set forth by President Ronald Reagan when he increased the federal gas tax in 1982, this transportation investment package is funded by everyone who uses our roads and highways:

• $7.3 billion by increasing diesel excise tax 20 cents
• $3.5 billion by increasing diesel sales tax to 5.75 percent
• $24.4 billion by increasing gasoline excise tax 12 cents
• $16.3 billion from an annual transportation improvement fee based on a vehicle’s value
• $200 million from an annual $100 Zero Emission Vehicle fee commencing in 2020.
• $706 million in General Fund loan repayments.

(Associated Press contributed to this report)