The Maryland Transportation Authority gave final approval Thursday to the largest package of toll increases in the state's history, which will double the cost of a round trip through the Baltimore harbor crossings to $8 by July 2013.

In another move, the agency also decided to move forward with a Baltimore County interchange it had previously eliminated from its $1 billion project to add express toll lanes to Interstate 95 in the White Marsh area. Officials said the restoration of the interchange at Route 43 was not related to the toll increase.

The unanimous vote on the tolls raises the cost of using all seven state toll facilities with fixed rates. The tolls for the Key Bridge, Fort McHenry Tunnel and Harbor Tunnel — now $2, collected both ways — will rise to $3 on Nov. 1 and to $4 in July 2013.

Toll rates for the John F. Kennedy Memorial Highway section of Interstate 95 and the Thomas J. Hatem Memorial Bridge on U.S. 40 in northeast Maryland, now $5 collected in one direction, will increase to $6 this year and to $8 in 2013.

The toll at the Bay Bridge, frozen at $2.50 since the 1970s, will rise to $4 in November and to $6 in 2013. The same toll hikes will apply to the U.S. 301 bridge between Southern Maryland and Virginia.

Commuter rates will increase at all those facilities for the first time in decades, though Maryland's frequent-user discounts remain among the most generous in the country. The original plan would have reduced the commuter discounts by as much as 90 percent. After the hearings, the board changed that figure to 75 percent.

The partially opened Intercounty Connector, which uses a variable-toll plan that can be adjusted according to congestion levels, was not affected by the changes in basic rates. The main section of that road is expected to open late this year or in early 2012.

The vote was the culmination of a long, contentious process that included 10 sometimes raucous public meetings around the state this summer. Money from tolls is used to finance the operations and construction of toll facilities, but many Marylanders expressed fears that the money would be diverted to other purposes.

While the public was cool toward any toll hikes, the authority said an annual revenue increase of $225 million was needed by 2014 to pay the debts from two mega-projects — the ICC and the express toll lanes being added to I-95 near Baltimore — and to cover the increasingly expensive upkeep of its aging facilities. Before Thursday's action, basic tolls for passenger vehicles had remained level since 2003.

"We had no choice but to raise tolls," said state Transportation Secretary Beverley K. Swaim-Staley, who chairs the board. "The commitments were made and the bills were due."

But state Sen. E.J. Pipkin, an Eastern Shore Republican, laid the blame for what he called "job-killing" increases at the feet of Swaim-Staley's boss, Gov. Martin O'Malley.

"Shame, shame, shame," Pipkin repeated in multiple interviews after the meeting. "The governor is a co-conspirator in this process."

At a meeting last week, the board pared back the hikes proposed for the Bay and U.S. 301 bridges but kept the other increases to basic tolls. Meanwhile, it made changes to ease the burden for motorists hauling trailers, commercial truckers and local users of the Hatem Bridge between Havre de Grace and Perryville.

The board also added a sweetener by rescinding an unpopular $1.50-a-month fee for most E-ZPass users. In addition, it adopted other incentives for drivers to switch to E-ZPass, including a 10 percent discount on tolls.

State Sen. Nancy Jacobs, a Republican who represents Harford and Cecil counties, said that while she was unhappy about the magnitude of the increases, she believed the board had listened to her constituents' concerns and made changes that improved the package.

Jacobs attended many of the board's meetings with the public and lobbied members for changes — particularly regarding the Hatem bridge and the treatment of drivers with trailers, who have had to pay high tolls because the trailers were classified as trucks. Jacobs said the board not only adopted some of her ideas but improved on some.

Throughout the debate, Pipkin denounced the transportation authority as a "runaway agency" that ignores public input.

Pipkin declined to say how he would meet the agency's obligations, which include the bills for the $2.4 billion ICC, and focused his wrath on the process by which tolls were raised without a vote by elected officials. He said the agency refused to conduct a facility-by-facility audit and did not make its final proposal public before voting on it.

"We're going to have a legislative package that's going to address the issue of the audit," he said.

Authority officials seemed puzzled by Pipkin's criticisms. Swaim-Staley said the authority was the subject of regular audits, both internal and by legislative analysts and outside consultants. She also noted that the toll changes had been fully discussed in an open work session last week.