With federal transportation funding about to run dry, President Barack Obama is taking steps to boost the flow of private dollars into public works projects.

The new initiative is designed to encourage collaboration between state and local governments and private-sector investors, expand the market for public-private partnerships and make greater use of federal credit programs. Obama was to announce the initiative in Delaware, using the recently closed I-495 bridge at the Port of Wilmington as a backdrop.

The bridge, a critical artery that normally carries an average of 90,000 vehicles daily through downtown Wilmington, was closed indefinitely last month after four support columns were found to be tilting, though not necessarily because of age. Officials think a mountain of dirt about two stories high that was dumped there by a contractor caused soil beneath the bridge columns to shift.

Obama's trip is part of a boarder effort to press Congress to keep money flowing to the Highway Trust Fund, the source of federal aid to states for surface transportation projects. The fund is expected to begin running out of money next month.

The Republican-controlled House passed a temporary funding bill this week to keep transportation aid flowing to states through next May, well after the midterm elections. A similar bill is pending in the Senate, though the chamber's Democratic leaders are expected to vote next week on the House-passed measure.

Transportation Secretary Anthony Foxx welcomed the progress on Capitol Hill, but said a short-term solution "is still insufficient to solve our crisis."

Obama supports a short-term fix because he said it will keep construction crews on the job and their projects on track, but he has devoted most of his public appearances this week to pressing Congress to either approve his four-year, $302 billion transportation proposal or come up with an alternative long-term funding measure.

Congress, meanwhile, has fewer than 10 days to complete action on a bill before its August recess. Lawmakers have kept the fund teetering on the edge of bankruptcy since 2008 through a series of temporary patches because they cannot agree on a politically acceptable, long-term funding solution.

From Delaware, Obama was traveling to New York City to raise campaign money at separate events for the Democratic Party and the House Majority PAC, which tries to help Democrats win House seats. The events were being held at separate private homes in Manhattan and were to be closed to media coverage.