HARRISBURG -- Advisers to Gov. Ed Rendell say the state could rake in up to $18 billion by leasing the Pennsylvania Turnpike to a private operator for 30 years, which in turn could produce funding for fixing miles of roads and hundreds of bridges and even generate enough money to bail out mass transit agencies.

The report, presented to state legislators yesterday by Rendell aide Roy Kienitz and two officials from New York City-based Morgan Stanley, outlines a best-case financial scenario for leasing the turnpike.

The report -- admittedly an educated estimate -- says the state should be able to get $12 billion to $18 billion from a private operator that would run the toll road for the next 30 years. If invested at a 9 percent rate of return, the upfront, one-time $18 billion payment would generate $1.62 billion a year for the state, the advisers say.

On the low end, if a 30-year lease fetched only $12 billion and the interest rate was 7 percent, the state would get $840 million a year, which wouldn't be enough to fix all the roads and bridges that need work.

A state transportation funding report issued in November estimates that $965 million a year is needed to repair all the current problem-ridden state-maintained roads and bridges. It also says that $760 million a year is needed to help Allegheny County's and Philadelphia's transit agencies and 71 others around the state -- a total of $1.725 billion a year in additional funds that are needed.

If Morgan Stanley's most optimistic estimates are accurate, it would mean the governor wouldn't need the new 6.17 percent tax on oil company profits he has proposed to help the transit agencies balance their budgets. Many Republican legislators have already pronounced the oil company tax "dead."

The Morgan Stanley report lists two other options for raising road/bridge/transit money, but neither is considered as strong a contender in the Legislature as the turnpike lease, an idea that Mr. Rendell has been pushing for several months.

Morgan Stanley says a new public agency could be created, with the flexibility under federal Internal Revenue Service rules to leverage tax-exempt bonds for fixing transportation. The report estimates that $900 million to $1.4 billion a year could be borrowed in this way, but that wouldn't be quite enough to fix all road and bridges and bail out transit.

The third option is the one outlined by the Pennsylvania Turnpike Commission, which is strongly opposed to the turnpike leasing plan and is fighting for its own survival.

The commission said it could raise $965 million a year by increasing tolls on the turnpike, slapping first-time tolls on Interstate 80 and imposing a $1 "congestion charge" at exits in southwest, southeast, Central and northeast Pennsylvania. Exits in the Pittsburgh area would be hit by the charge.

Mr. Kienitz refused to say if Mr. Rendell has a preference among the three options. Privatizing the turnpike -- leasing it to a private operator to generate billions of dollars -- is, however, something he's favorably mentioned in recent weeks.

Mr. Rendell has been using a figure of about $10 billion for what a turnpike lease could fetch, so the maximum figure of $18 billion released yesterday is a considerable improvement.

Mr. Kienitz said that in a few days, the administration will send legislators a bill that would allow the governor to go forward with seeking bids from private operators that want to run the turnpike. It would let him seek binding bids from as many as 47 groups that have already submitted "expressions of interest" in such a lease.

If the Legislature approves such a bill, and that could take weeks or months, the governor could move to the next step -- seeking bids and then leasing the turnpike to the highest bidder.

The bill that Mr. Rendell will soon introduce is the Legislature's only chance to kill the turnpike-leasing deal. Once it's approved and Mr. Rendell solicits bids from private companies, he won't return to the Legislature for approval of the highest bid, Mr. Kienitz said.

The prospect of generating as much as $18 billion -- and thus solving the state's needs for funding for roads, bridges and transit -- is one that legislators may find hard to vote against. It removes any need to increase the gasoline tax or motor vehicle registration fees, ideas that also have been mentioned as ways to get money for transportation improvements.

Rep. Rick Geist, R-Altoona, chairman of the House Transportation Committee, said privatization of the turnpike "is a project worth taking a very good look at." But as to whether the Legislature will act on the privatization bill before summer recess starts June 30, he said, "that would be a stretch."

Some Senate Republicans who don't like the idea of leasing the turnpike criticized Mr. Rendell yesterday for giving Morgan Stanley such a lucrative contract for its work -- as much as $15 million, depending on how big the actual 30-year lease fee is.

Republicans said it's in Morgan Stanley's interest to push for leasing the turnpike regardless of whether it's the best plan, because the firm will get a big fee.

Republicans also claimed that Morgan Stanley could wind up as the investment banker for the project, working for the successful bidder and earning even more money.

Mr. Kienitz and two Morgan Stanley officials, Rob Collins and Stratford Shields, said the firm would have no role in the project other than advising the Rendell administration.