Given that direction, apparently no transportation idea was too far-fetched for consideration. The study's authors examined the merits of electric skateboards, segways and motorcycles (both regular and with attached sidecars). Various types of aircraft were also examined, such as helicopters, blimps and personal jets. They even considered some outlandish prototypes like flying cars, hover bikes and automated drones.

Now complete and available online , the final version of the transit report indicates that the study was retooled midway. Originally, traffic engineers focused solely on building a light rail extension (expected to cost up to $500 million), but they were later asked to broaden the study to include other alternatives.

For the last three years, there have been almost no public updates on the study, and its status has been kept a secret even after it missed completion dates. Officials with VTA and Mountain View have told the Voice they could not disclose details because the study was owned by Google.

The report released this week is the product of a lengthy partnership between Google and VTA officials that was originally announced back in 2015. At the time, Google paid the transit agency $1 million to study extending the light-rail system out to the heavily congested North Bayshore tech hub.

Building expressways for autonomous vehicles could be the best option for creating a new transit link to Mountain View's North Bayshore neighborhood, according to a new report produced by the Santa Clara Valley Transportation Authority (VTA).

Autonomous vehicles were seen as one of the most promising options in the study. The VTA report pointed out that this technology could soon be adopted for mass transit: a self-driving bus, for example. Alternatively, self-driving cars could be chained into a "platoon" that could operate more like a train. VTA officials studied the possibility of building dedicated tracks for self-driving cars so they could speedily move past traffic congestion. Another option would be to build an elevated track.

The VTA report graded transit options based on price, the ability to move riders and the level of impact on the environment and surroundings. The study authors also wanted a transit system that could be easily linked to current systems and expanded later in the future.

In the end, the rapidly advancing technology for autonomous vehicles rose to the top as one of the best options in the Google-funded study. No mention was made of the company's own self-driving division -- Waymo -- but the study did reference various other companies developing this technology.

All these aviation ideas were eliminated for being too immature, but the study indicated they could someday be dusted off as feasible transit options.

Going forward, it will be up to Google officials to decide what to do with the new transit report, according to VTA officials.

Two potential routes were proposed in the study. A dedicated expressway for autonomous vehicles could run west along Highway 101 from the Bayshore / NASA station to Inigo Way, where it would turn into North Bayshore. Alternatively, a route for self-driving cars, buses or light rail could be brought up R.T. Jones Road along the NASA Ames campus. This option would require a new bridge to be built across Stevens Creek.

Any transit systems would need to start at the Bayshore / NASA light rail station and go about 2.5 miles to the center of Google's campus at Shoreline Boulevard and Charleston Road.

VTA study plugs autonomous vehicles for MV transit

Google-funded study looks to link North Bayshore with transit