Even under the most conservative ridership projections, the report said the rail system would have a net operating profit.
It pegs ridership at anywhere from 7.4 million to 10.8 million riders by 2025 for an initial southbound phase. Even at low ridership projections, the project would have a net operating profit of $352 million a year, the report said.
The average ticket between San Francisco and Los Angeles would cost $81 in non-adjusted dollars, with express trains completing the trip in less than three hours.
The Democratic governor asked his two summer appointees to take a hard look at the project. Richard spent 12 years on the board of the Bay Area Rapid Transit system, and retired Bank of America executive Michael E. Rossi also is Brown's jobs adviser.
Under the revised business plan, initial construction would start with a $5.2 billion "spine" from Fresno to Bakersfield to be completed in 2017. The line would then be extended further north or south - from Merced to Palmdale, in the Los Angeles basin, or from Bakersfield to San Jose.
The first 130-mile segment would create about 100,000 jobs in the hard-hit Central Valley, according to the report. Building the entire system would generate about 1 million jobs.
The report notes that while the $98.5 billion tab seems high, California's growing population would otherwise require about $170 billion in new infrastructure, such as freeways and airport runways.
Brown said in August that he still supports the plan to link San Francisco with Los Angeles and Anaheim by 2020, but his Department of Finance is expected to review the proposal in detail before he signs off.
Late Monday, Brown issued a statement saying the first section in the Central Valley will create jobs "at a time when we really need them." He also noted that a high-speed rail line will accommodate the state's population growth "without the huge expense and intractable problems of massive highway and airport expansion."
State Sen. Alan Lowenthal, D-Long Beach, a one-time proponent of the project and chairman of the Senate select committee on high-speed rail, has said California should consider returning the $3.5 billion in federal grants and halting the project unless the authority lays out a clear path to finance, build and operate the system. He said California taxpayers must not be on the hook for unexpected cost overruns.
Some lawmakers were being briefed on the plan Monday night.
In a report issued last July, a peer-review committee created as part of the 2008 ballot measure that approved $9 billion in bonds said later phases of the rail project rely almost entirely on federal, state and local money that might never materialize. That poses a risk that whatever is started will not be finished and might be of little use to most California residents, that review said.
The Legislature, which returns in January, must approve the proposal, along with Brown.