Los Angeles Times » The Los Angeles Times analysis of California’s high-speed rail project concludes that the state has underestimated the project’s challenges, and completion of the rail line will be delayed, leading to cost overruns. According to Oxford University professor Bent Flyvberg, high-speed rail projects such as this have an average cost overrun of 45%. This article provides an overview of similar megaprojects, and the challenges, including delays and increased costs, associated with tunneling.