Across the United States, more state and local governments are tapping private dollars to build, repair and maintain public infrastructure. Here are some of the biggest and most-watched projects:
*Pennsylvania is pushing to replace at least 500 bridges under a single contract in the next five years. On March 26 the state invited four construction teams to submit bids.
If the project were to use traditional public financing, it would cost about $1.2 billion, said Bryan Kendro, director of public-private partnerships in Pennsylvania's Transportation Department.
"We expect proposals to come in well below that," he said.
*The Port Authority of New York and New Jersey closed a $1.5 billion deal in November to rebuild the Goethals Bridge, which links New York's Staten Island to New Jersey.
The Port Authority will reimburse the private developers with regular payments for making the road or bridge available for use. The use of these "availability payments" is on the rise, said John Medina, a global project analyst at Moody's Investors Service.
*The Port Authority is also currently reviewing bids from three pre-qualified private development teams to replace the central terminal at LaGuardia Airport. The project will cost an estimated $3.6 billion altogether, though the construction contract to design, build, operate and maintain the facility through 2050 is for $2.6 billion. Completion isn't expected before 2021.
*The $2.36 billion Ohio River Bridges project will construct two spans between Indiana and Kentucky. Indiana is using a P3 approach to build one of the spans because the state allows such deals. But Kentucky, which has no such law, is using traditional public financing.
The same company is designing and building both bridges. Indiana helped the developer finance the project with nearly $677 million of tax-exempt private activity bonds in March 2013. The state will also make availability payments and milestone payments.
*In January, Maryland invited four teams to bid on a contract to design, build, finance, operate and maintain the Purple Line, a 16-mile light rail system between Bethesda and Prince George's County. When completed, it will be operated by the private developer. But it will connect directly to Washington, D.C.'s existing Metrorail system, run by the Washington Metropolitan Transit Authority, a public entity.
The state says the private sector is expected to invest $500 million to $900 million in the project, which has a total price tag of $2.2 billion. Construction could be completed by spring 2015.
*Florida's Transportation Department received financial proposals in March from four shortlisted teams to revitalize its Interstate 4 corridor, which runs through Orlando to link Tampa on the west coast and Daytona Beach on the east.
The state hopes to have a contract signed by July, a spokeswoman said. The project, which is estimated to begin in winter 2015, will cost at least an estimated $2.8 billion and will rebuild 15 interchanges, replace more than 75 bridges, add four tolled express lanes and rebuild general use lanes.
(Editing by Dan Burns and Douglas Royalty)