The Pennsylvania Turnpike Commission will borrow $532 million this week toward a possible record $9.6 billion in loans to provide extra funds for the state's roads, bridges and public transit.

The commission is scheduled to close on the loan Thursday in order to start raising money for the Pennsylvania Department of Transportation under the new "public-public partnership" between the two agencies.

It is the first segment of record turnpike borrowing authorized over the next 16 years under state legislation known as Act 44 that the Legislature passed and Gov. Ed Rendell signed in July to provide more revenue for roads, bridges and 73 public transit systems.

The bonds are to be repaid through a combination of tolling Interstate 80, beginning in 2011, and raising tolls on the turnpike, starting in 2009 with a 25 percent increase.

Act 44 estimates it will be the 2024-25 fiscal year before the turnpike commission has enough extra money from those two sources to continue paying PennDOT while meeting its own debt obligations without further borrowing. Overall, the legislation calls for generating $116 billion over the next 50 years.

The turnpike commission could still be paying off a $9.6 billion debt, plus hundreds of millions of dollars in interest, depending on interest rates, through the middle of the century.

"[Borrowing] was the decision made by a majority of members of the General Assembly as the way to approach transition funding," PennDOT spokesman Rich Kirkpatrick said. "The governor preferred leasing the turnpike [to private investment interests], but legislators chose to go this direction."

The initial $532 million will be split three ways:

$62.5 million will be retained by the turnpike commission as reimbursement for a similar amount taken from its cash reserves and sent to PennDOT Aug. 6 as the initial payment under the Act 44 partnership. A total of $750 million is to be sent to PennDOT this fiscal year, $850 million next year and $900 million in 2009-10.

Two payments of $229.17 million each will go to PennDOT, one at the end of this month and the other in January.

The remaining $11.6 million is to be used for capitalized interest, insurance and costs of issuing the bonds, including $230,000 to Dilworth Paxon, a Philadelphia law firm; $137,500 to Cohen & Grigsby, of Pittsburgh, the underwriter counsel; $10,000 to Hopkins & Co., of Oak Park, Ill., financial underwriter; and an amount not yet determined to Citi, part of Citigroup Inc., of New York City, senior underwriter for the bond issue.

The turnpike commission anticipates floating another $450 million in bonds by May 1. Of that, $229.19 million will be used to fulfill the remainder of its first year, $750 million obligation to PennDOT.

U.S. Rep. John Peterson, R-Venango, one of the elected officials trying to block the conversion of I-80 into a toll road, said in a statement Friday that tolling the 311-mile highway "has a lot to do with paying off debt and fixing problems that should have been addressed years ago."

He said assuming the Federal Highway Administration will approve I-80 as the nation's third and last pilot interstate tolling project "is a classic case of putting the cart before the horse."

Last week, PennDOT and the turnpike commission signed a 50-year agreement to turn maintenance and operation of the highway over to PennDOT. They also submitted a formal application to the FHWA.

If the state fails to gain FHWA approval to toll I-80, the commission will still be required to turn over $450 million a year to PennDOT from turnpike toll increases on the 360-mile east-west mainline and 110-mile Northeast Extension from Philadelphia to the Poconos.

And if revenues are insufficient to pay off the series of bonds that the commission has been authorized to issue under Act 44, the Legislature has pledged highway-bridge money from the Motor License Fund, which includes state gasoline tax revenue and motor vehicle fees such as commercial truck registrations.

A "fiscal note" in Act 44 explains: "The pledge is only a guarantee against a default in order to secure a more favorable interest rate on the special revenue bonds."

Mr. Kirkpatrick said while the act calls for the commission to take on debt, "it outlines the revenue sources to pay for that debt. Act 44 is the law and we're proceeding on that basis."

PennDOT had borrowed about $2 billion dollars in the 1960s and 1970s, but former Gov. Dick Thornburgh and his PennDOT secretary, Dr. Thomas Larson, stopped the practice during their administration and put the state's transportation program on a pay-as-you-go basis.

Nevertheless, as a result of the long-term bond obligations made by predecessors, PennDOT will for another eight years still be paying off its old debt for roads and bridges built 40 years ago.

The difference between PennDOT then and the turnpike commission now is the Legislature didn't provide a means to pay its debt, said state Rep. Joe Markosek, D-Monroeville, chairman of the House Transportation Committee.

Mr. Markosek said the issue of extra transportation funding, always a political hot potato, couldn't wait longer because of growing needs across the state.

If the federal government does not allow tolling I-80, Mr. Markosek said lawmakers will have to regroup and "start from scratch."

He conceded that tolling currently free I-80 and raising turnpike tolls represent an indirect means of taxation for some people.