Imagine stepping on a train in Portland at noon and stepping off about two hours later in Vancouver, British Columbia.

Passengers would whiz past Seattle in less than an hour.

Oregon, Washington and British Columbia governments are hoping to take that far-flung vision and turn it into a reality by 2035. High-level transportation officials from each will meet Tuesday for a second discussion this year about what a so-called ultra-high-speed rail line connecting the three cities would look like.

The rail discussion is in its infancy, but the governments hope to work with private companies to set the groundwork for bullet trains in what they are calling the "Cascadia megaregion." Government, business and academic leaders are hosting the annual Cascadia Innovation Corridor conference in Vancouver this week.

No ultra high-speed trains currently operate in the U.S. The fastest train, Amtrak's Acela Express, hits maximum speeds of 154 miles per hour but averages about half that speed on its route between Washington D.C. and Boston.

Amtrak's Cascades route already connects Portland and Vancouver via the passenger rail network, but it runs only four times each day between Portland and Seattle and infrequently to Canada.

Read more: Cascadia train would be world's 2nd fastest

According to an initial report from the Washington Department of Transportation released in February, the Cascadia route could cost $25 billion to more than $40 billion to build.

Who would pay for the mega project remains unclear, but it could be a public-private partnership.

Gov. Kate Brown called the effort the first of its kind for the region. "It brings together public and private partners such as Microsoft to build the business case and make it a reality," she said in a statement. "This could provide big returns for the State of Oregon and a much-needed transportation option."

Cascadia is one of what planners say are 11 megaregions in the country, those geographic swaths with shared economies, infrastructure and ecosystems. The region is already connected by its "educated and skilled workforce, similar public policies, academic institutions and a culture of innovation," according to the report, but as of yet the economics have been disconnected. With population in the three cities expected to hit a collective 11.2 million by 2040, the governments believe a high-speed rail connection would bridge that economic gulf.

The freeway network is expected to hit capacity, and "speed constraints limit regional mobility, and economic development and global competitiveness."

One option could be a magnetic-levitation train with speeds greater than 250 miles an hour, with seven stations between Vancouver and Portland. One route would put the station at the Rose Quarter Transit Center, others would place the station at Portland International Airport.

According to an economic feasibility analysis, paid for by Microsoft and published earlier this year, the plan could create 38,000 construction jobs for a decade, driving an estimated $29 billion in labor income. The analysis indicated the rail network would require a workforce of 3,000 employees to operate.

The rail project, a long-standing dream for transit leaders, re-emerged two years ago as a talking point of ways to boost regional economic partnerships.

Janet Matkin, Washington Department of Transportation's rail communications manager, said a more in-depth study is underway. That study should shed more light on potential travel times, but estimates show it would take less than an hour to get from Portland to Seattle.

"The business case study currently being conducted will re-look at all station options to identify costs, ridership, economic impacts, and other factors that will be used to evaluate the viability of this project," Matkin said in an email.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen