Construction of a $420 million “bus rapid transit” line from St. Paul to White Bear Lake could begin as soon as 2023, depending upon the results of an environmental study that will begin this year.

The Ramsey County Regional Railroad Authority voted Tuesday to endorse the 20-station route and vehicle type, joining the cities of St. Paul, Maplewood, White Bear Lake, Vadnais Heights, Gem Lake and White Bear Township.

The vote to endorse the “locally preferred alternative” was based on input from an advisory committee and task force, which has met since 2014 to study cost, ridership projections, travel time, development potential and access to jobs, diverse populations and activity centers.

An environmental study will unfold over the next two years, providing additional opportunities for public input.

The study will include preliminary design of 20 bus station stops, with special focus on how those stops link to cycling, driving, walking and other transit routes. More information is online at rushline.org.