FACTBOX: McCain and Obama infrastructure priorities

(Reuters) - U.S. presidential candidates, Republican John McCain and Democrat Barack Obama, have spent the past week articulating policy goals for shoring up and modernizing the nation's infrastructure.

The American Society of Civil Engineers estimates that $1.6 trillion is needed over a five-year period to bring, roads, bridges, power plants, levees, rail lines and other systems into a state of good repair.

Here are some of the candidates' infrastructure policy proposals:

MCCAIN

* Energy. Proposes to build 45 nuclear reactors by the year 2030. Longer-term goal is 100 new plants. Plans to commit $2 billion annually until 2024 to clean-coal research, development and construction of demonstration plants. "We will make clean coal a reality." McCain also supports enhanced development of wind, solar and other alternative energy sources.

* Grid. Proposes "serious investment" to upgrade national electric power transmission system, which will include capacity to charge electric cars if they are brought to market and mass produced in the next decade. Proponent of SmartMeter technology, designed to give more precise picture of energy consumption and encourage more cost-efficient use of power. U.S. grid comprises nearly 160,000 miles of high-voltage transmission lines. Existing systems not designed for current demand.

* Roads/Bridges. McCain has not proposed a blueprint for road, rail and bridge construction though he is a fierce critic of how Congress loads up infrastructure spending bills with pet projects for members and special interests. He vows to seek line-item authority to veto what he calls wasteful spending. McCain this spring proposed a federal gas tax holiday to ease pump prices, which critics said would diminish receipts the government dedicates for highway and transit projects. One in four U.S. bridges is structurally deficient.

* Rail. In the Senate, McCain as a member of the Commerce Committee and the panel's former chair has, like many Republicans, opposes federal subsidies for Amtrak, the national passenger service. But he recognizes Amtrak provides some important service, especially in the Northeast. Last year, he backed legislation approved by the Senate to provide long-term capital funding for passenger rail but would overhaul the way service is managed. Legislation now pending would provide $15 billion for Amtrak and other rail projects over five years.

OBAMA

* Energy independence. Proposed $150 billion over 10 years to advance biofuels, renewable energy and clean coal plants. Favors incentives for communities to invest in biofuel refineries. Wants to establish a federal investment program to help manufacturers modernize infrastructure, adopt clean technology.

* Grid. Wants major investment in transition to a digital U.S. electricity grid. Wants to require that 25 percent of electricity consumed is derived from renewable sources.

* Roads/bridges/ports. Proposed $60 billion National Infrastructure Reinvestment Bank over 10 years to rebuild roads, bridges, ports and rail. Also wants to leverage private investment to help fund improvements. Part of this money would go to upgrading grid for powering electric cars. The U.S. spends about $59 billion annually on transportation infrastructure.

* Rail. Obama is from Chicago which is a hub for much-maligned Amtrak long-distance service. He supports continued subsidies for the rail line, with operating reforms to improve accountability, as well as development of high-speed corridors -- 500 miles or less -- between major cities. Also wants to expand freight rail capacity and invest in mass transit. The U.S. government estimates $20 billion is needed annually improve transit systems nationwide.

* Air traffic. Proposes to modernize aging air traffic control system. Democratic-led Congress failed this spring to approve legislation that would provide long-term funding for upgrading air traffic infrastructure to help reduce delays and congestion at major airports.

* Tech. Wants to make available broadband Internet access to all U.S. communities.

Additional source: American Society of Civil Engineers

(Reporting by John Crawley; Editing by Eric Walsh)