Construction will begin next year with the 209km Central Valley "backbone" section from north of Bakersfield to south of Merced, which will cost around $US 6bn and is due to be completed in 2017. This will be extended to create the initial operating section (IOS), either from Merced to the San Fernando Valley (IOS North, $US 27.2bn) or Bakersfield to San Jose (IOS South, $US 24.7bn). Construction will begin on this phase in 2015, and once completed in 2021 will allow the operation of the United States' first true high-speed rail services. CHSRA says ridership projections show either option will allow operations to at least break even.\r\nThe third phase would be the remainder of the above options, or the so-called 'Bay to Basin' link between the San Francisco Bay Area and the Los Angeles basin, connecting with commuter rail services in both cities, at a cost of $US 21.1bn. Construction would begin in 2021 and take around five years.\r\nPhase 4 would be built after 2026 and complete the San Francisco - Los Angeles section or additional improvements in the Los Angeles and San Francisco areas to extend high-speed services onto the existing network to serve the centres of these cities, as well as Anaheim southeast of Los Angeles. This project would cost $US 23.9bn and would include electrification of existing lines.\r\nThe extension of the network north to Sacramento and south from Anaheim to San Diego are longer-term prospects, which will be completed beyond 2030.\r\nEach segment has been designed to independently cover its operating costs with no public subsidy. CHSRA says cost estimates are based on realistic assumptions and a credible assessment of the resources required. It has also allowed a nine-year construction schedule cushion to cover for potential delays and funding gaps, together with $US 16bn in contingencies for material cost increases and changes in quantities.\r\nThe funds required to begin the initial Central Valley section have already been secured, including $US 3.3bn in federal funds and $US 2.7bn in state bond funding, and new funding sources will be identified before any further construction begins. The plan assumes no further funding from Washington will be available before 2014.\r\nCHSRA says that once passenger services are running on the IOS it hopes ridership and revenue will facilitate private investment in subsequent phases of the network.