Rep. Barbara Comstock (R-Va.) unveiled her long-awaited Metro bill on Monday, proposing to increase federal funding for the transit agency by 50 percent in exchange for creating a temporary reform board, adopting tough measures to hold down labor costs and other changes.

Comstock’s 77-page bill, which she took more than a year to draft in consultation with regional business groups, may have more impact than numerous other recent Metro restructuring plans. That’s because the Northern Virginia lawmaker is the only Republican in the GOP-dominated Congress who represents Washington suburbs served by Metro.

The legislation echoes some proposals already pushed by Metro General Manager Paul J. Wiede­feld and former U.S. transportation secretary Ray LaHood.

But it differs by requiring that the Metro Compact, or governing document, be amended to create the five-member reform board. It would block federal funding to Metro until the District, Maryland and Virginia enacted such legislation.

Comstock’s bill aims to pry additional funding for Metro from a skeptical Congress to help cover an estimated $500 million a year to ensure safety and reliability. In return, it would overhaul the much-criticized board and adopt long-term changes designed to improve the agency’s governance, finances and operations.

The bill also calls for further revisions of the compact, which would ultimately lead to creation of a permanent, nine-member governing board to replace the current 16-member board. It would give the U.S. transportation secretary additional authority over the board and funding.

Both Wiedefeld and LaHood have resisted revising the compact, because it is a cumbersome process that typically requires years to accomplish. They say Metro can’t afford to wait that long to make reforms and increase funding.

The reform board proposed by Comstock would have the authority to unilaterally revise union agreements and contracts with suppliers. Her bill would weaken pension guarantees, cap overtime and freeze Metro’s personnel-related expenses for five years.

The attraction for Metro would be the potential, significant increase in federal funding. If the changes were made, Comstock’s bill would increase the federal subsidy for Metro from $150 million a year to an average of $225 million a year over 10 years.

The U.S. transportation secretary would have the discretion to delay granting the additional $75 million a year in federal funds if Metro wasn’t making sufficient progress in specified areas such as finances, safety and efficiency.

“The money is the leverage to get the significant reforms that are needed,” Comstock said. “We want good business practices put in place.”

The federal grant, which covers capital costs such as the purchase of new rail cars, would continue to be matched by the three local jurisdictions. That means the District, Maryland and Virginia would each increase their match from $50 million to $75 million a year.

Comstock said the support from the business community — including from Democrats such as former District mayor Anthony Williams — showed that her bill represented a consensus.

“Everybody has to come to the table and compromise,” she said.

More than 30 business and nonprofit groups in the Metro Reform Coalition — including the Greater Washington Board of Trade, Federal City Council and Northern Virginia Chamber of Commerce — signed a statement welcoming Comstock’s bill.

“We strongly believe that comprehensive reform to Metro’s governance and funding will lead to operational improvement across the system,” the three-paragraph statement said.

But the bill’s labor provisions effectively guarantee that the Washington region’s Democratic-dominated congressional delegation would be split over the legislation, which does not have a co-sponsor.

“What looks like reform in one mind can be perceived as deliberate union-busting and anti-labor to another person’s view,” said Rep. Gerald E. Connolly (D-Va.).

He also expressed reservations about the bill on grounds that reopening the compact would be difficult and said Comstock’s bill would die without bipartisan support from the region.

“For this to have a fighting chance, you need to have the Democrats of the national capital region on the bill,” Connolly said. “You can have all the boards of trade and all of the Republicans . . . it will not become law because the other side of this coin is conservative Republicans, who don’t want to help anyhow, [and] are going to point to that deficiency.”

Connolly said he is drafting his own bill, which would not reopen the compact and would provide a more substantial funding increase than Comstock’s.

Rep. John Delaney (D-Md.), who already has submitted a bill, endorsed a bipartisan approach but did not take a specific stand on Comstock’s legislation.

Two other Democratic congressmen from the Maryland suburbs — Reps. Anthony G. Brown and Jamie Raskin — recently proposed legislation to strengthen protections for Metro workers in a bill drafted in coordination with the transit agency’s principal union, Amalgamated Transit Union Local 689.

Tom Davis, the former Republican congressman from Northern Virginia who led the fight to win the federal subsidy for Metro a decade ago, said Comstock’s bill offered the only chance for extending the program, which is scheduled to expire in the next fiscal year. “This is the only game in town,” said Davis, who has advised Metro in his current job as a managing director at Deloitte. “With Republicans controlling both ends of Pennsylvania Avenue, and [federal] funding running out next year, this is our only shot.”

Comstock said she hoped to have hearings on her bill “as soon as possible” in the new year. She said the funding proposal may be included as part of a broad transportation bill that could come before the House in the spring.

Her bill includes several measures to hold down labor costs, partly to win support from the GOP. It would adopt a recommendation from Wiedefeld to amend a federal law known as the Wolf Act to strengthen management’s hand in labor disputes that go to arbitration. But it stops short of ending mandatory binding arbitration, as Comstock and other Republicans have supported in the past.

It also follows a Wiedefeld recommendation providing that future Metro hires would have defined contribution pensions, which are less generous than the defined benefit pensions now given to many workers.

Comstock’s bill comes on the eve of the official release Tuesday of a Metro plan from LaHood, who was commissioned by Virginia Gov. Terry McAuliffe (D) to craft a regionwide consensus for reforming the agency.

Like Comstock, LaHood called for a five-member reform board to replace Metro’s 16-member panel. But Comstock’s plan would give more authority to the U.S. Transportation Department.

Comstock’s bill provides that the reform board would be in place for at least three years, while the District, Maryland and Virginia draft a new compact.

That new compact, which would require approval by Congress, would set up a permanent, nine-member board. The District, Maryland, Virginia and the federal government would each have two members. The ninth, who would be chair, would be selected jointly by the two governors and mayor.

Faiz Siddiqui contributed to this story.