Fresno Mayor Ashley Swearengin has the right perspective on high-speed rail. She recalls I-5, which took from 1947 to 1979 to complete, segment-by-segment. "It began in the Central Valley," she notes. "It was called the 'road to nowhere.' It was called 'too expensive.' Today, it is the backbone of surface transportation in California."

The latest business plan from the California High-Speed Rail Authority will not change the minds of long-time critics – there's still too much unknown about this major infrastructure project that will take decades to complete. But it should provide comfort to those who do believe that rail should be a part of California's 21st-century transportation network.

The new plan is much more explicit about tying the system together with existing commuter and intercity rail systems, promising "connections at all new high-speed rail stations to existing regional and local transit systems." In particular, the new plan calls for getting spending under way quickly using $950 million set aside by voters in Proposition 1A for regional and local rail improvements.

That's important politically, too, because calling for early investments in the regional rail systems helps to build a constituency to build the backbone of the high-speed rail system in the Central Valley.

The money is in place for that initial 130-mile segment from Bakersfield to Fresno, allowing construction to begin in 2012, with expected completion in 2017. Other segments will take additional money, planning and authorization, but that is not unusual. Nearly every country with high-speed rail built it in increments. Spain, for instance, built its initial line from Madrid to Seville between 1988 and 1991. It then took 17 years to complete other segments, including one to Barcelona.

The rail authority argues persuasively that California, under any scenario, will have to expand its transportation system to relieve airport and highway congestion. The busiest short-haul air travel market in the United States is between the Los Angeles and San Francisco metropolitan areas. California's 170,000 miles of roadway are the busiest in the nation. Six California urban areas rank in the 30 most congested in the nation: Los Angeles-Long Beach-Santa Ana, San Francisco-Oakland, San Jose, San Diego, Riverside-San Bernardino, and Sacramento.

Meeting the demands of growth will cost billions, one way or another, over the next generation.

The new plan is explicit about dividing the project into a series of smaller, discrete segments that build upon each other but also can stand alone.

Under the new plan, as in Europe, connecting service through the big urban areas will be provided by sharing existing commuter rail infrastructure and facilities – existing Caltrain in the Bay Area and existing Metrolink in the Los Angeles Basin. This welcome shift will require upgrades to get through urban areas at up to 125 miles per hour. But the idea of dedicated tracks, significant structure or tunnel work, and additional right-of-way beyond the blended system would be put off to the future.

In the end, Californians weighing the multi-billion-dollar cost of high-speed rail and improved conventional rail also have to consider the alternative – the cost of expanding the state's highways or building new airports. This latest plan makes it ever-more-clear that many details remain to be worked out – and any estimates will have to be continually revisited. This remains high-risk.

The issue, really, for California – with its $1.9 trillion economy, among the 10 largest in the world – is whether we can get past the current malaise and, in the words of Gov. Jerry Brown, "think big again."

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