U.S. lawmakers are renewing efforts to expand the use of municipal bonds to attract private investment in the nation’s crumbling roads and bridges.

Senator Ron Wyden, the Democrat who backed legislation creating the $188 billion market for Build America Bonds, plans to introduce a bill Monday that would facilitate the use of private-activity debt for transportation projects. Separately, Republican Representative Todd Young wants to double the limit on the securities for transportation and allow their use for facilities such as courthouses. Companies use private-activity bonds to borrow in the municipal market.

The plans may face an uphill battle because of their cost and gridlock on Capitol Hill. Yet increasing financing options for public-private partnerships would be a boon for municipalities and help fill a void, the lawmakers said. Authorization for federal highway funding is set to expire May 31, and Congress has been unable to agree on a plan to address what Treasury Secretary Jacob J. Lew says is a $1 trillion backlog of infrastructure work.

“You can come up with bipartisan approaches to get private-sector money off the sidelines and into transportation,” Wyden, 66, the ranking Democrat on the Finance Committee, said in a phone interview. “The transportation system needs more than a face lift; it basically needs full re- constructive surgery.”

Debt Limit

States and localities issue private-activity bonds on behalf of companies that build and operate facilities such as airports, ports and highways. There’s a limit to how much of the debt can be sold: as of April 15, $11.1 billion of the $15 billion allotted for transportation had been issued or approved, including for the replacement of the Goethals Bridge between New York City and New Jersey.

Municipalities nationwide sold Build America Bonds, taxable debt with a federal subsidy on interest costs, for infrastructure. Wyden, who represents Oregon, has tried unsuccessfully to revive the program, which debuted in 2009 and expired at the end of 2010.

The senator calls his latest proposal the “Move America” program. Co-sponsored by Republican Senator John Hoeven of North Dakota, it would authorize as much as $180 billion of tax-exempt bonds over 10 years and provide as much as $45 billion in new infrastructure tax credits to match private-equity investment.