That money will be spent on transportation infrastructure whether high-speed rail gets built or not. Currently the flights between Northern and Southern California are ranked among the busiest routes for air traffic in the world with millions of passengers per year (link). As the population of the state increases more airport runways and facilities will need to be built unless we have HSR up and running. Freeways through heavily urbanized North-South corridors will need to be widened, such as S.F. to Gilroy or L.A. to San Diego. Thirty years from now it's possible that they will need to widen most of highway 99 as the Central Valley's population continues to grow.
Exactly right. The alternative to high speed rail isn't not spending anything. The alternative to high speed rail is spending tens of billions of dollars on highway and airport expansions. Widening I-5 in San Diego County, alone, is expected to cost between $3B - $5B. Bringing Highway 99 to interstate standards has been estimated to cost $25B.
Admittedly, high speed rail is extensive but some perspective is much-needed. Yonah Freemark of the Transport Politic,
had a good post about this last year. California's GDP over the 22 years that construction of high speed rail will take will be $42 trillion dollars. High speed rail is expected to cost $70B. According to Mr. Freemark, this is 0.20 percent of the entire California economy over this period. Assuming a constant $13B annual Caltrans budget over this period, just under $300B will be spent on transportation (http://www.thetransportpolitic.com/2...be-understood/
). This is a little more than one-half of one percent of California's economic output over this period.