Getting from Vancouver to Seattle can take upwards of three hours by car or train, but an ultra-fast railway service could zip people between the cities in less than 60 minutes.

That's according to the latest study exploring the potential benefits of an ultra-high-speed rail line stretching from British Columbia down to Oregon.

The business case analysis released Monday also boasts the service would reduce greenhouse gas emissions by six million tonnes over its first four decades, and potentially create $355 billion in economic growth.

Washington Governor Jay Inslee said the findings provide "even greater confidence that an ultra-high-speed ground transportation system in the Pacific Northwest is worth the investment."

"The ability to travel each segment between Seattle, Portland, and Vancouver, B.C. in less than an hour will revolutionize the way we live, work, and play," Inslee said in an executive summary of the study.

"Moreover, it helps us preserve the natural beauty and health of our region by enabling faster, cleaner and greener trips between our region's largest cities."

The study estimates the train could run as many as 30 round trips a day, and carry 32,000 people an hour. If the line is built, the study said it could eventually be used for as many as one-in-five trips between the participating cities.

But it wouldn't be cheap. Previous estimates pegged the up-front construction costs at anywhere from US$24 billion to US$42 billion.

The 2019 business case, which is considered the most comprehensive and detailed exploration of the concept to date, found that cost estimates still stands.

Any potential construction is still many years away. The project still needs to be designed, then given the necessary approvals, including environmental clearance. But the existing studies' feasibility findings are still cause for excitement, said Bruce Ralston, the province's minister of jobs, trade and technology.

"Improving the connectivity in the Pacific Northwest region presents enormous potential for job creation, economic growth and environmental benefits on both sides of the border," Ralston said in a statement.

"We look forward to continuing discussions with the State of Washington and other partners."

The B.C. government has been working with officials in Washington and Oregon on the project, as well as staff at Microsoft.

The province put up $300,000 for the business case last year, and has committed another $300,000 to continue moving the process forward.