A plane lands at Dulles airport as workers build the second phase of Metro's Silver Line to Dulles. (Katherine Frey/The Washington Post)

A new study shows Metro workers’ pay and benefits are in line with those of other major transit systems, blunting long-standing criticism of the agency’s labor costs.

But Northern Virginia Republican lawmakers said it would still be necessary for Metro to restrain costs and weaken union powers to persuade the GOP-led General Assembly in Richmond to back increased funding for the transit system.

The report by a consulting firm hired by the state of Virginia undermined complaints that Metro’s labor costs are excessive — an allegation aired frequently by critics including GOP political leaders.

The study by the firm WSP USA said total employee compensation at Metro was $56 for every hour worked by a Metro employee, compared with an average of $58 at four other transit systems that, like Metro, do not allow workers to strike.

The average was $61 for four systems that do permit strikes.

[Virginia Gov. McAuliffe taps Ray LaHood to head panel to study Metro.]

The study is the first significant report released publicly to guide the work of a politically important commission that is studying Metro and is chaired by former U.S. transportation secretary Ray LaHood.

LaHood plans to issue a report in September recommending changes in Metro’s funding and governance aimed at winning broad support across the Washington region.

The new study, on which LaHood will rely, weakens the case for seeking a major rollback of labor costs and union power, as some GOP lawmakers in Virginia and Congress have advocated.

“Basically what we’re finding is both wages and benefits [at Metro] are average for the transit industry,” said WSP consultant Roy Kienitz, who conducted the study for the Virginia Department of Rail and Public Transportation.

Kienitz presented the results Wednesday evening at a public committee meeting of the Northern Virginia Transportation Commission in Arlington.

[Lawmakers suggest Metro unions derailing efforts for internal cost-cutting.]

The WSP study found Metro was more generous than other transit systems in a few respects. Unlike most systems, Metro credits overtime pay in calculating pension benefits. Also, the average Metro union employee contributes just 3.1 percent of salary to their pension, compared with an average of 7.1 percent for U.S. public employees.

But Metro was squarely in the mainstream by numerous other measures:

●The average Metro employee earns 106 percent of the amount needed for one adult and one child to attain “a modest yet adequate standard of living” in the D.C. region — equal to the average for eight other major transit systems.

●Average retirement benefits at Metro are 56 percent of final salary, compared with 60 percent for 20 selected local governments.

●Metro’s pensions are 77 percent funded, which is the average for the nation’s 100 largest public pension funds.

Some previous studies have also found that Metro’s pay levels were generally in line with industry norms. But critics have said it was necessary nonetheless to strengthen management’s hand in bargaining with unions over pay and operating procedures.

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At the Wednesday meeting, Virginia Del. James M. LeMunyon (R-Fairfax) pressed Kienitz to explain why Federal Transit Administration data show Metro’s rail operating cost is 62 cents per passenger mile, compared with 32 cents in San Francisco and 39 cents in Chicago.

Kienitz said the higher costs were attributable to higher maintenance expenses at Metro, and because Metro keeps trains in service for more hours each week relative to its ridership. He also noted Metro pays more than other systems for riders’ comfort, offering “big wide cars and nice, comfy seats.”

After the meeting, LeMunyon questioned that those factors alone could explain such a large cost difference.

“I have a hard time buying that,” he said.

He also told the transportation commission meeting the Virginia legislature would need to see a much more detailed plan for a Metro turnaround before it agreed to give the system additional funds.

Metro has said it needs at least $500 million a year in additional funds, starting mid-2018, for new equipment and maintenance to restore it to a state of good repair.

“If you want them [legislators] to invest in something, they want to know what they’re investing in,” LeMunyon said.

In a related development, Loudoun Supervisor Matthew F. Letourneau (R-Dulles) presented a four-page document urging changes in Metro’s collective bargaining agreement with its largest union, Amalgamated Transit Union Local 689, to save money and improve efficiency.

The proposal included calls to allow Metro to hire more part-time employees, and allow management to fix work schedules without being subject to outside arbitration.